PNEUMATIC EXCAVATOR AND METHODS OF USE

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]This application claims the benefit of U.S. Provisional Patent Application Nos. 63/441,954, 63/441,957, 63/441,961, and 63/441,966, filed Jan. 30, 2023, and Ser. No. 18/416,112, Ser. No. 18/416,024, Ser. No. 18/416,082, and Ser. No. 18/416,050, filed Jan. 18, 2024, each entitled “PNEUMATIC EXCAVATOR AND METHODS OF USE”, each of which are herein incorporated by reference in their entireties for any useful purpose.

TECHNICAL FIELD

[0002]Implementations are directed to excavators, and more particularly to hand-held pneumatic excavators and methods of use.

BACKGROUND

[0003]Compressed air excavators cause compressed air to exit from a nozzle disposed at an end of an open pipe, which may be useful in operations such as loosening soil from buried pipes, gas mains, cables and cleaning. In prior approaches, pressurized water directed at the soil resulted in the generation of hazardous waste by the water mixing with contaminants in the soil that requires special treatment prior to disposal. In other approaches, mechanical digging implements such as blades and picks having hard cutting edges often damage the objects to be excavated or cleaned. The use of compressed air has the advantage of avoiding generation of hazardous waste while loosening soil without causing damage to the object targeted.

SUMMARY

[0004]Pneumatic excavators and methods of use are thus provided. According to implementations, a pneumatic excavator configured to be pneumatically actuated may include an actuator; a flow valve fluidly coupled to the actuator by at least one air actuation conduit; and a barrel coupled to an egress of the flow valve, wherein an egress of the barrel defines an outlet of the pneumatic excavator. A primary flow passage is defined at least by the flow valve and the barrel. Actuating the actuator may cause compressed air to be transmitted from the actuator through the at least one air actuation conduit to a first port of the flow valve to cause the flow valve to move to an open position such that compressed air from a supply of compressed air passes through the primary flow passage and exits through the outlet of the pneumatic excavator. Releasing the actuator causes the compressed air to be transmitted from the actuator through the at least one air actuation conduit to a second port of the flow valve to cause the flow valve to move to a closed position. In in the closed position, the flow valve prevents the compressed air from the supply of compressed air from passing therethrough.

[0005]In various implementations and alternatives, the air actuation conduit may further include a first air actuation conduit and a second air actuation conduit, the first air actuation conduit may extend between a first port of the actuator and the first port of the flow valve, the second air actuation conduit may extend between a second port of the actuator and the second port of the flow valve.

[0006]In various implementations and alternatives, the at least one air actuation conduit may include a constant pressure conduit, where a first end of the constant pressure conduit is coupled to the pneumatic excavator at an upstream position from an egress of the flow valve, and a second end of the constant pressure conduit is coupled to the actuator. In such implementations and alternatives, the air actuation conduit may further include the first and second air actuation conduits extending between the actuator and flow valve as provided. In such implementations and alternatives, the actuator may further include a valve. When the actuator is actuated, the valve may be configured to fluidly couple the constant pressure conduit to the first air actuation conduit, and when the actuator is not actuated or is released, the valve may be configured to fluidly couple the constant pressure conduit to the second air actuation conduit. In such implementations and alternatives, the valve may include a trigger biased by a biasing mechanism configured to be manually actuated.

[0007]In various implementations and alternatives, in the closed position of the flow valve, a piston of the flow valve may seal against a valve seat. In addition or alternatively, at least one vent port may be provided and configured to vent the compressed air from the flow valve. For instance, the vent port may be defined in the actuator.

[0008]In various implementations and alternatives, the actuator may include a trigger biased by a biasing mechanism. For instance, the biasing mechanism may include a return spring.

[0009]In various implementations and alternatives, the flow valve may be free of a biasing mechanism such that the flow valve requires the compressed air to move the flow valve to the open position and to the closed position.

[0010]According to other implementations, a method of pneumatically actuating a pneumatic excavator may involve supplying compressed air to a pneumatic excavator from a compressed air supply. The pneumatic excavator may include an elongated barrel, an actuator and a flow valve, the elongated barrel having an ingress and an egress, said ingress configured to be fluidly connected to the supply of compressed air, said egress defining an outlet of the pneumatic excavator, the actuator comprising at least one air actuation conduit and configured to be fluidly connected to the supply of compressed air, the flow valve fluidly coupled to the actuator via the at least one air actuation conduit, wherein a primary flow passage is defined at least by the flow valve and the barrel. The method may proceed by actuating the actuator to cause compressed air to be transmitted from the actuator through the at least one air actuation conduit to the flow valve to cause the flow valve to move to an open position, wherein in the open position of the flow valve, the compressed air from the compressed air supply passes through the primary flow passage and exits through the outlet of the pneumatic excavator. The actuator may be released to cause the compressed air to be transmitted from the actuator through the at least one air actuation conduit to the flow valve to cause the flow valve to move to a closed position, wherein in the closed position, the flow valve prevents the compressed air from passing therethrough.

[0011]In various implementations and alternatives, the wherein the air actuation conduit further comprises a first air actuation conduit and a second air actuation conduit. When the actuator is actuated, the compressed air may be transmitted through the first air actuation conduit to the flow valve, and wherein when the actuator is released, the compressed air may be transmitted through the second air actuation conduit to the flow valve.

[0012]In various implementations and alternatives, the at least one air actuation conduit may include a constant pressure conduit, and the compressed air may be constantly delivered to the constant pressure conduit and to the actuator during the supplying of compressed air. In such implementations and alternatives, the air actuation conduit may further include a first air actuation conduit and a second air actuation conduit, and when the actuator is actuated, the compressed air may be transmitted through the first air actuation conduit to the flow valve, and when the actuator is released, the compressed air may be transmitted through the second air actuation conduit to the flow valve. In such implementations and alternatives, the actuator may further include a valve. When the actuator is actuated, the valve may be configured cause the compressed air to be transmitted through the constant pressure conduit to the first air actuation conduit, and when the actuator is not actuated or is released, the valve may be configured to cause the compressed air to be transmitted through the constant pressure conduit to the second air actuation conduit.

[0013]Various implementations and alternatives may further involve venting compressed air from the flow valve when the flow valve is in at least one of the open position or the closed position. In such implementations and alternatives, the actuator may be biased by a biasing mechanism such that the releasing of the actuator causes the actuator to move to an unbiased position.

[0014]In various implementations and alternatives, the flow valve may be free of a biasing mechanism such that the flow valve requires the compressed air to move the flow valve to the open position and to the closed position.

[0015]Implementations additionally provide pneumatic excavators configured to be pneumatically actuated. According to implementations, a pneumatic excavator includes a primary actuator; a secondary actuator fluidly coupled to the primary actuator; a shuttle valve may include a first inlet port fluidly coupled to a delivery port of the primary actuator, a second inlet port fluidly coupled to a delivery port of the secondary actuator; a flow valve may include a first port fluidly coupled to the primary actuator by at least one air actuation conduit and a second port fluidly coupled to an exit port of the shuttle valve; a barrel coupled to an egress of the flow valve, where an egress of the barrel defines an outlet of the pneumatic excavator. A primary flow passage may be defined at least by the flow valve and the barrel. Actuating the primary actuator and the secondary actuator causes compressed air to be transmitted from the secondary actuator to the primary actuator and through the at least one air actuation conduit to the first port of the flow valve to cause the flow valve to move to an open position such that the compressed air from the supply of compressed air passes through the primary flow passage and exits through the outlet of the pneumatic excavator. Then, when actuating one of the primary actuator or the secondary actuator and not actuating the other, causes the compressed air to be transmitted to the exit port of the shuttle valve fluidly coupled to the second port of the flow valve to cause the flow valve to move to a closed position, where in the closed position, the flow valve prevents the compressed air from the supply of compressed air from passing therethrough.

[0016]In various implementations and alternatives, a constant pressure conduit may be included, where a first end of the constant pressure conduit may be coupled to the pneumatic excavator at an upstream position from an egress of the flow valve, and a second end of the constant pressure conduit may be coupled to the secondary actuator.

[0017]In such implementations and alternatives, an air conduit may be provided that fluidly couples the primary actuator to the secondary actuator, where when the secondary actuator is actuated, the air conduit may be fluidly coupled to the constant pressure conduit. In addition or alternatively, the primary actuator further includes a primary actuator valve, and as the secondary actuator is actuated and when the primary actuator is actuated, the primary actuator valve may be configured to fluidly couple the constant pressure conduit to the first port of the flow valve. In addition or alternatively, as the secondary actuator is actuated and the primary actuator is not actuated, the delivery port of the primary actuator fluidly couples the air conduit to the first inlet port of the shuttle valve.

[0018]In implementations alternatives including the constant pressure conduit, the secondary actuator may further include a secondary actuator valve, where when the primary actuator is actuated and the secondary actuator is not actuated, the delivery port of the secondary actuator valve may be configured to fluidly couple the constant pressure conduit to the second inlet port of the shuttle valve.

[0019]In various implementations and alternatives, when neither the primary actuator nor the secondary actuator are actuated, the secondary actuator may be configured to transmit the compressed air via the delivery port to the second inlet port of the shuttle valve such that the flow valve is retained in the closed position or caused to move to the closed position, where in the closed position, the flow valve prevents the compressed air from the supply of compressed air from passing therethrough.

[0020]In various implementations and alternatives, at least one of the primary actuator or the secondary actuator may include a spool valve having a spool biased by a biasing mechanism. In such implementations and alternatives, the biasing mechanism may include a return spring.

[0021]In various implementations and alternatives, in the closed position of the flow valve, a piston of the flow valve may seal against a valve seat.

[0022]In various implementations and alternatives, at least one vent port may be included and configured to vent compressed air from the flow valve. In such implementations and alternatives, at least one vent port may be defined in the primary actuator or the secondary actuator.

[0023]In various implementations and alternatives, the flow valve may be free of a biasing mechanism such that the flow valve requires the compressed air to move the flow valve to the open position and to the closed position.

[0024]According to other implementations, a method of pneumatically actuating a pneumatic excavator may involve supplying compressed air to a pneumatic excavator from a compressed air supply, the pneumatic excavator may include an elongated barrel, a primary actuator, a secondary actuator, and a flow valve, the elongated barrel having an ingress and an egress, said ingress configured to be fluidly connected to the supply of compressed air, said egress defining an outlet of the pneumatic excavator, the primary actuator may include at least one air actuation conduit and the primary actuator configured to be fluidly coupled to a shuttle valve, the secondary actuator fluidly coupled to the primary actuator and to the shuttle valve, the flow valve fluidly coupled to the primary actuator and to the shuttle valve, where a primary flow passage is defined at least by the flow valve and the barrel. The primary actuator and the secondary actuator may be actuated to cause compressed air to be transmitted from the secondary actuator to the primary actuator to the flow valve to cause the flow valve to move to an open position such that the compressed air from the supply of compressed air passes through the primary flow passage and exits through the outlet of the pneumatic excavator. Then one of the primary actuator or the secondary actuator may be actuated while the other is not actuated, causing the compressed air to be transmitted to the shuttle valve to the flow valve to cause the flow valve to move to a closed position such that the compressed air from the supply of compressed air may be prevented from passing through the flow valve.

[0025]In various implementations and alternatives, during the supplying of compressed air, compressed air may be constantly delivered to a constant pressure conduit fluidly coupled to an intake port of the secondary actuator. In such implementations and alternatives, the actuating of one and not the other, involves actuating the secondary actuator and not the primary actuator, and where the air actuation conduit further includes a first air actuation conduit fluidly coupling the primary actuator and the secondary actuator such that the compressed air may be constantly delivered to the air actuation conduit and to the primary actuator.

[0026]In addition or alternatively, the air actuation conduit may further include a first air actuation conduit and a second air actuation conduit, and during the actuating of the primary actuator and the secondary actuator, the first air actuation conduit may fluidly couple the primary actuator and the secondary actuator such that the compressed air may be constantly delivered to the first air actuation conduit and to the primary actuator, and the second air actuation conduit fluidly couples the primary actuator and the flow valve such that the compressed air may be constantly delivered from the primary actuator to the flow valve. In addition or alternatively, actuating one actuator and not the other includes actuating the primary actuator and not the secondary actuator, and the secondary actuator further includes an air conduit fluidly coupling a delivery port of the secondary actuator and the shuttle valve such that the compressed air may be constantly delivered to the shuttle valve via the air conduit.

[0027]In various implementations and alternatives, during actuation of one of the primary actuator or the secondary actuator and not the other, the shuttle valve may allow air to enter an entry port from the actuated actuator and prevents air from entering the shuttle valve from the other unactuated actuator.

[0028]In various implementations and alternatives, the flow valve may be free of a biasing mechanism such that the flow valve requires the compressed air to move the flow valve to the open position and to the closed position.

[0029]In yet further implementations, pneumatic excavators configured for delivering pulsed compressed air are provided. According to implementations, a pneumatic excavator configured for delivering pulsed compressed air includes an actuator; a controller valve fluidly coupled to the actuator by at least one air conduit; a flow valve fluidly coupled to the controller valve by at least one port of the flow valve; a barrel coupled to an egress of the flow valve, wherein an egress of the barrel defines an outlet of the pneumatic excavator; and a pulse control line configured as an air conduit extending between the controller valve and a port of the primary flow passage downstream from the egress of the flow valve. A primary flow passage is defined at least by the flow valve and the barrel. As air from a compressed air supply flows through the primary flow passage, the pulse control line may be pressurized by the air and causes a spool pilot of the controller valve to be pressurized and to shift the controller valve to an actuated position to cause the compressed air to be delivered to a port of the at least one port of the flow valve such that the flow valve moves to a closed position and prevents the air from the compressed air supply from flowing through the primary flow passage. Upon the flow valve moving to the closed position, the pulse control line may no longer be pressurized and the controller valve may shift to an unactuated position to cause the compressed air to be delivered to another port of the at least one port of the flow valve such that the flow valve opens and permits the air from the compressed air supply to flow through the primary flow passage and again pressurize the pulse control line, whereby pulsed compressed air is delivered through the primary flow passage of the pneumatic excavator.

[0030]In various implementations and alternatives, the controller valve may further include a spool, where when the spool pilot is pressurized, the spool may be caused to shift to thereby move the controller valve to the actuated position, and when the spool pilot is no longer pressurized, the spool may shift to thereby move the controller valve to the unactuated position. In such implementations and alternatives, the spool may be biased by a biasing mechanism, and when the spool pilot is not pressurized, the spool may be in a normal position. For instance, the biasing mechanism may be a return spring.

[0031]In various implementations and alternatives, the controller valve may further include an adjustment device configured to control a pulse rate of the pulsed compressed air. For instance, the adjustment device may be configured to control an orifice size of the pulse control line.

[0032]In various implementations and alternatives, the controller valve may further include a selector switch configured to move between at least two positions, where in a first position of the selector switch, the pneumatic excavator may be configured to deliver the pulsed compressed air, and in a second position of the selector switch, the pneumatic excavator may be configured to deliver a constant flow of the air from the compressed air supply through the primary flow passage. For instance, during the constant flow of the air through the primary flow passage while the actuator is actuated, the compressed air may be transmitted by the at least one air conduit to the at least one port of the flow valve via the controller valve such that the compressed air causes the flow valve to move to the open position to thereby permit air from the compressed air supply to flow through the primary flow passage. Alternatively, during the constant flow of the air through the primary flow passage while the actuator is actuated, the controller valve may not be pressurized.

[0033]In various implementations and alternatives, actuating the actuator may cause the air from the compressed air supply to flow through the primary flow passage.

[0034]According to other implementations, a method of delivering pulsed compressed air through a pneumatic excavator comprising an actuator, a controller valve, and a primary flow passage defined at least by a flow valve, a barrel and a nozzle defining an outlet of the pneumatic excavator, and the method may involve providing, from a compressed air supply, a constant supply of compressed air to the pneumatic excavator. Then actuating the actuator, where in a first phase of actuation, the actuator delivers a first portion of compressed air to a port of the flow valve such that the first portion of compressed air moves the flow valve to an open position to thereby open the flow valve and permit a second portion of compressed air to pass through the primary flow passage. In this first phase of actuation, the controller valve is in an unactuated position. In a second phase of actuation, a pulse control line of the controller valve is pressurized by the second portion of the compressed air passing through the primary flow passage and causes the controller valve to be pressurized and to shift to an actuated position to cause the actuator to deliver compressed air to another port of the flow valve such that the flow valve moves to a closed position and prevents the second portion of compressed air to pass through the primary flow passage. Upon the flow valve moving to the closed position, the pulse control line and the controller valve are no longer pressurized such that the spool shifts to the unactuated position such that the actuator returns to the first phase of actuation and thereby permits the second portion of compressed air to pass through the primary flow passage and again pressurize the pulse control line, whereby pulsed compressed air is delivered through the primary flow passage of the pneumatic excavator.

[0035]In various implementations and alternatives, when the actuator is not actuated, the first portion of compressed air may be transmitted from the actuator to the flow valve via the controller valve such that the first portion of compressed air holds the piston of the flow valve in the closed position to thereby prevent the second portion of compressed air from passing through the flow valve.

[0036]In various implementations and alternatives, in the first phase of actuation, the first portion of compressed air is delivered to a first port of the at least one port of the flow valve such that the first portion of compressed air holds the piston in the open position, and in the second phase of actuation, the first portion of compressed air is delivered to a second port of the at least one port of the flow valve such that the first portion of compressed air holds the piston in the closed position.

[0037]In various implementations and alternatives, the method may further involve using a selector switch to select a pulse mode of operation of the pneumatic excavator such that the pulsed compressed air is provided through the primary flow passage. Such implementations and alternatives may further involve using the selector switch to select a constant flow mode of operation of the pneumatic excavator, and when the constant flow mode of operation is selected, the pulse control line and the spool pilot are inactivated and the first portion of compressed air from the second air hose fluidly couples to the first port of the flow valve and air holds the piston in the open position to thereby open the flow valve and permit the second portion of compressed air to pass therethrough and through the primary flow passage.

[0038]In various implementations and alternatives, the method may further involve releasing the actuator such that the actuator is not actuated and the first portion of compressed air is transmitted from the actuator to the first air hose and holds the piston of the flow valve in the closed position to thereby prevent the second portion of compressed air from passing through the flow valve.

[0039]In various implementations and alternatives, the method may further involve venting the flow valve when the flow valve is in at least one of the open position or the closed position.

[0040]In still further implementations, pneumatic excavators may include releasably coupled actuators, in which an exemplary excavator includes an elongated barrel having an ingress and an egress, said ingress configured to be fluidly connected to a supply of compressed air, said egress defining an outlet of the pneumatic excavator; an actuator including an actuation switch; a releasable coupling configured to releasably couple the actuator to the barrel in a plurality of locked positions along a length of the barrel, such that the actuator is movably coupled to an exterior of the barrel; and a flow valve fixedly arranged to the barrel, where the flow valve is in a communicative coupling with the actuator by an actuation conduit. The actuation conduit may be flexible and slaved by an adjustment movement of the actuator relative to the flow valve along the length of the barrel to thereby maintain the communicative coupling therebetween such that when the actuator is actuated, the actuation conduit may send a signal to the flow valve to move to an open position and the compressed air passes through the flow valve and the barrel and exits the pneumatic excavator through the outlet, and when the actuator is released, the actuation conduit may send a signal to the flow valve to move to a closed position to prevent the compressed air from passing through the flow valve.

[0041]In various implementations and alternatives, the actuation conduit may be configured as tubing, where the signal from the tubing is compressed air emitted from the actuator. In such implementations and alternatives, the tubing may include a first tubing and a second tubing, the first tubing extending between a first port of the actuator and a first port of the flow valve, the second tubing extending between a second port of the actuator and a second port of the flow valve. In addition or alternatively, the tubing may be coiled tubing configured to be coiled around or strung along the barrel. In addition or alternatively, the tubing may be telescopic.

[0042]In various implementations and alternatives, the actuation conduit may include an electrical conduit, where the signal from the tubing is an electrical signal emitted from the actuator.

[0043]In various implementations and alternatives, the releasable coupling may include a sleeve-shaped portion surrounding the barrel, which may be locked and unlocked by a locking mechanism. In such implementations and alternatives, the locking mechanism may include a clamp.

[0044]In various implementations and alternatives, the actuator may further include a first handle, where the first handle is configured to be held by one hand of a user and provide access to the actuation switch by the one hand. In such implementations and alternatives, a second handle may be positioned on the exterior of the barrel. For instance, the second handle may be configured to releasably couple to the barrel in a plurality of locked positions along the length of the barrel independent from the releasable coupling.

[0045]In various implementations and alternatives, a handle positioned on the exterior of the barrel, and in such implementations and alternatives, the handle may be configured to releasably couple to the barrel in a plurality of locked positions along the length of the barrel independent from the releasable coupling.

[0046]In various implementations and alternatives, the actuator may be a primary actuator, and the pneumatic excavator may further include a safety mechanism including a secondary actuator, where the actuation switch and the secondary actuator are both actuated for the primary actuator to be actuated. In such implementations and alternatives, the actuation switch and the secondary actuator may be separately arranged on the barrel such that the actuation switch is configured to be depressed by one hand of a user and the secondary actuator is configured to be depressed by another hand of the user. In addition or alternatively, the releasable coupling may be a first releasable coupling, and the pneumatic excavator may further include a second releasable coupling, the second releasable coupling including the secondary actuator, and where the first releasable coupling and the second releasable coupling are movable relative to each other along the length of the barrel.

[0047]In various implementations and alternatives, a nozzle may be coupled to the egress of the barrel and may define the outlet of the pneumatic excavator. In addition or alternatively, an adjustable shield may be slidably arranged on the barrel proximate the distal end.

[0048]According to other implementations, a method of operating a pneumatic excavator including a movable actuator may involve: adjusting a position of a releasable coupling including an actuator along a length of an elongated barrel of the pneumatic excavator, the pneumatic excavator including a flexible actuation conduit forming a communicative coupling between actuator and a flow valve fixedly arranged on the barrel, and where the actuation conduit is slaved by the adjusting to thereby maintain the communicative coupling; locking the releasable coupling to the barrel; supplying compressed air to an ingress of the flow valve; and actuating the actuator such that the actuation conduit sends a signal to the flow valve to move to an open position and the compressed air passes through the flow valve and the barrel and exits the pneumatic excavator through the outlet.

[0049]In various implementations and alternatives, the method may further involve releasing the actuator such that the actuation conduit sends a signal to the flow valve to move to a closed position to prevent the compressed air from passing through the flow valve.

BRIEF DESCRIPTION OF THE DRAWINGS

[0050]FIG. 1 illustrates a pneumatic air excavator in use in an excavating operation, according to implementations of the present disclosure;

[0051]FIG. 2A1 and 2A2, 2B1 and 2B2, and 2C illustrate a first isometric view, an exploded isometric view, and a second isometric view, respectively, of the pneumatic air excavator, according to implementations of the present disclosure;

[0052]FIG. 2D shows the pneumatic air excavator with an alternative fitting position, according to implementations of the present disclosure;

[0053]FIG. 3 illustrates a detail view of components of the pneumatic air excavator, according to implementations of the present disclosure;

[0054]FIGS. 4A and 4B illustrate a valve of the pneumatic air excavator in a closed position and in an open position, respectively, according to implementations of the present disclosure;

[0055]FIGS. 5A and 5B illustrate different positions of a handle of the pneumatic air excavator, according to implementations of the present disclosure;

[0056]FIG. 6 illustrates a flow diagram of a method of actuating the pneumatic air excavator, according to implementations of the present disclosure;

[0057]FIGS. 7A and 7B illustrate pneumatic circuit diagrams of the pneumatic excavator, according to implementations of the present disclosure;

[0058]FIG. 8 illustrates a flow diagram of a method of pneumatically actuating the pneumatic air excavator, according to implementations of the present disclosure;

[0059]FIGS. 9A-9C illustrate pneumatic circuit diagrams of the pneumatic excavator including a safety mechanism, according to implementations of the present disclosure;

[0060]FIG. 10 illustrates a flow diagram of a method of actuating the pneumatic air excavator, according to implementations of the present disclosure;

[0061]FIGS. 11A-11F illustrate pneumatic circuit diagrams of the pneumatic excavator including a controller valve for controlling flow modes of the pneumatic excavator, according to implementations of the present disclosure; and

[0062]FIG. 12 illustrates a flow diagram of a method of pneumatically actuating the pneumatic air excavator, according to implementations of the present disclosure.

DETAILED DESCRIPTION

[0063]Turning to the Figures, FIG. 1 illustrates a pneumatic air excavator 100 of the present disclosure in an exemplary soil excavating operation. A proximal end 110 of the pneumatic air excavator 100 is removably coupled to an air supply via an elongated delivery line 111. The air supply may be compressed or pressurized air, which may be provided by an air compressor such as an air compressor truck. The air supply may be air (e.g., a mixture of oxygen and nitrogen), a gas or a mixture. A distal end 120 of the pneumatic air excavator 100 may include an extension 122 and a nozzle 130 (see, e.g., FIG. 2A1 and 2A2) configured to deliver the compressed air, for instance, to break apart soil covering a buried target object, e.g., a pipe, cable, or other structure(s). A barrel 140 extending between the proximal and distal end 110, 120 of the pneumatic air excavator 100 may be held by a user P during use. The barrel 140 may include an actuator assembly 150 movably coupled to an exterior 141 of the barrel 140 by a releasable coupling 160 (see, e.g., FIG. 2A1 and 2A2). The actuator assembly 150 may be held by one hand of the user P for controlling an on/off status of the pneumatic air excavator 100, while a different region of the pneumatic air excavator 100 may be held by the other hand of the user P, such as at a safety mechanism 165 proximate a primary valve or flow valve 170. As the soil is loosened during operation of the pneumatic air excavator 100, an industrial vacuum V may extract the loosened soil and may for instance deposit the soil in a location for future use or removal.

[0064]FIG. 2A1 and 2A2, and 2B1 and 2B2 illustrate an isometric view and an exploded isometric view, respectively, of the pneumatic air excavator 100 of the present disclosure. As shown in FIG. 2A1 and 2A2, components of the pneumatic air excavator 100 may be coaxially arranged such as the nozzle 130, barrel 140, portions of the actuator assembly 150, the releasable coupling 160, a safety mechanism 165 and the primary flow valve 170. A primary flow passage 105 of the pneumatic air excavator 100 may extend along a central axis thereof and may be defined at least by the flow valve 170, the barrel 140 and nozzle 130.

[0065]At the proximal end 110 of the air excavator 100, a port or fitting 112 may be provided for removably connecting to the air supply via the delivery line 111 to establish a fluid coupling to the air supply. For instance the delivery line 111 may include a fitting that is complementary to the fitting 112, or the two may otherwise be configured for coupling to one another directly or indirectly to provide an air tight connection. For instance, the fitting 112 may be a quick connect fitting, a claw connector such as a Chicago claw connector, or other air supply connection. The proximal end 110 may optionally include an angled conduit or pipe 113 and/or a straight conduit or pipe 114, each of which may for instance facilitate ergonomics of using the pneumatic air excavator 100 when coupled to the delivery line 111. Alternatively, the port or fitting 112 may be positioned at a distal end 120 of the air excavator 100, as shown in FIG. 2D, and for instance may be arranged distal to the actuator assembly 150 and the releasable coupling 160. In such case, the barrel 140 extending between the proximal and distal ends 110, 120 may enable the releasable coupling 160 to be moved to various positions along the barrel 140 and locked thereto, and this portion of the barrel 140, in some instances, may not receive airflow from the air supply, and may thereby provide flexibility in the configuration of the releasable coupling 160 and the barrel 140. Arrangement of the port or fitting 112 at the distal end 120 may lower the center of gravity of the pneumatic excavator to a more centralized position, for instance to provide better ergonomics and reduce fatigue. In such examples, the barrel 140 may be arranged both at the inlet end 179 of the flow valve 170 and the outlet end 178 of the flow valve 170 as shown in FIG. 2D.

[0066]The distal end 120 of the pneumatic air excavator 100 may define an outlet and may include a nozzle 130 coupled thereto. For instance, the nozzle 130 may be coupled to an egress of the barrel 140, and the nozzle 130 may define an outlet for the pneumatic excavator 100. The nozzle 130 may have various configurations depending on the desired delivery pressure and flow geometry emitted therefrom. For instance, the nozzle 130 may have a supersonic nozzle design. The nozzle 130 may be constructed of various materials such as metal including brass, stainless steel, composites such as polymers, reinforced polymers, a combined construction of metallic and polymer materials, and combinations thereof. The type of nozzle may include but is not limited to 30-300 cubic feet per minute (cfm) at 70 to 250 psi. The nozzle 130 may be interchangeable with other nozzles and may be releasably coupled to the distal end 120 such as via a threaded engagement or other fastening mechanism, e.g., quick connect. Alternatively, the nozzle 130 may be non-detachably connected to the distal end 120 of the pneumatic air excavator 100. In addition or alternatively, the nozzle 130 may include a non-conductive cover or coating, e.g., a rubber, polymer, of the like, for protecting the air excavator 100 and user from electrical shocks during excavation operations near power sources.

[0067]In some implementations, the distal end 120 of the pneumatic air excavator 100 may be formed of an optional barrel extension 122 as illustrated in FIG. 1. The barrel extension 122 may have the same or a different configuration as the barrel 140 of the pneumatic air excavator 100 and may be detachably coupled to the barrel 140 such as via a threaded collar or via another fastening mechanism such as those disclosed herein. The barrel extension 122 may enable the user P to use the pneumatic air excavator 100 in excavation applications at varying depths, and for instance, a longer extension 122 may be joined to the barrel 140 when the target object has a depth that is deeper than the length of the barrel 140. This may enable the user P to operate the pneumatic air excavator 100 more comfortably, as the user may operate the system in a standing position instead of a kneeling or bent position. In some implementations, the extension 122 and the barrel 140 may be telescopically arranged, and the length of the pneumatic air excavator 100 may be adjustable, such as by operating an adjustment collar that permits telescopic movement of the extension 122 relative to the barrel 140. The extension 122 may be constructed of the same or different material from the barrel 140, and for instance may be constructed of a non-conductive material such as fiberglass, plastics, rubbers, polymers, lined or coated material, aluminum, and so on.

[0068]The barrel 140 may define a portion of the primary flow passage 105 of the pneumatic air excavator 100 for delivering compressed air to the nozzle 130. The barrel 140 may be configured as a rigid, elongated tubular conduit having an ingress and an egress, and the ends may be coupled to various components as described herein, e.g., the ingress may be coupled to the delivery line 111 and the egress may be coupled to the nozzle 130 in a detachable or non-detachable manner. The barrel 140 may be constructed of a non-conductive material such as fiberglass, plastics, rubbers, polymers, lined or coated material, aluminum, and so on. In some implementations, an adjustable shield 142 may be slidably arranged on the barrel 140 proximate the distal end (FIG. 2C). The adjustable shield 142 may be cone-shaped and may deflect debris during an excavation operation.

[0069]The actuator assembly 150 of the pneumatic air excavator 100 may be arranged along the barrel 140 for instance as shown in FIG. 2A1, 2A2, 2C and 2D. The actuator assembly 150 may generally include an actuation switch and may be releasably coupled to the barrel 140 by the releasable coupling 160 described herein. The actuation switch of the actuator assembly 150 may include a trigger 151, e.g., a push button, coupled to a trigger valve 152. The trigger 151 may be biased by a biasing mechanism such as a spring or a solenoid valve. For instance, the trigger valve 152 may include a spool valve with a spool and spool pilot, where the spool is biased by a biasing mechanism such as a spring or solenoid valve, and the trigger 151 may move the spool against the bias force of the biasing mechanism. An actuation conduit 153 may at least be coupled between the actuator assembly 150 and the flow valve 170 and between the safety mechanism 165 and the actuator assembly. The actuation conduit 153 may be movably adjustable as provided herein and may include one or more conduits such as air hoses or conductive wires.

[0070]Operation of the actuation switch may cause the pneumatic air excavator 100 to be turned on and off. For instance, to activate the actuator assembly 150, the actuation switch may be moved to a closed position, e.g., by depressing the trigger 151. In response, the actuation conduit 153 coupled between the actuator assembly 150 and the flow valve 170 sends a signal to cause the main valve 170 to move to an open position, such that compressed gas from the delivery line 111 is permitted to pass through the main valve 170 as well as the primary flow passage 105 of the pneumatic air excavator 100 such that the compressed air exits through the nozzle 130. The actuator assembly 150 may be deactivated or released by the actuation switch moving to an open position, e.g., by releasing the trigger 151. Where the trigger 151 includes a biasing mechanism, deactivation may cause the trigger 151 to move to a normal position where the biasing mechanism, e.g., a return spring, is relaxed. In response, the actuation conduit 153 may send a signal to cause the flow valve 170 to move to a closed position to prevent the compressed gas from passing through the main valve 170 and thus the primary flow passage 105. The actuation conduit 153 may be a flexible conduit that can be extended and retracted along the barrel 140 of the pneumatic air excavator 100. For instance, the actuation conduit 153 may be configured as flexible air tubing (e.g., an air actuation conduit), as a flexible electrical conduit (e.g., a conductive wire), and may be coiled around the barrel 140, strung along the barrel 140, e.g., between the actuator assembly 150 and the flow valve 170, or may be telescopic along the barrel 140. In some implementations, a sleeve may cover the actuation conduit 153. The actuation conduit 153 may be provided as one or more conduits. For instance, one, two, three, four, five six, seven or more conduits may be provided in the actuation conduit.

[0071]Although the actuator assembly 150 is illustrated as being positioned on the releasable coupling 160, the actuator assembly 150 may alternatively be positioned on the flow valve 170 or another portion of the pneumatic air excavator 100. In addition or alternatively, although the actuator assembly 150 is illustrated as being positioned distal to the flow valve 170, the actuator assembly and, in some cases, the releasable coupling 160 carrying the actuator assembly 150, may alternatively be positioned proximal to the flow valve 170 of the pneumatic air excavator 100.

[0072]The releasable coupling 160 may be configured to releasably couple the actuator assembly 150 to the barrel 140 in a plurality of locked positions along a length of the barrel 140 when in a released position, and may be locked or fixed to the exterior 141 of the barrel 140 in the locked position. The releasable coupling 160 may include a sleeve-shaped portion 161 (FIG. 3) surrounding the barrel 140, which may be locked and unlocked by a locking mechanism 162 such as a clamp or a cam lock, e.g., clamping handle coupled to a split ring or clamp, for establishing a pinch, compression, and/or friction lock. The locking mechanism 162 may engage with the barrel 140 via a pinch or clamping mechanism along the external diameter of the barrel 140. In an unlocked position of the locking mechanism 162, the releasable coupling 160 may be in a released position and be moved or slid along the exterior 141 of the barrel 140, and due to the actuation conduit 153 being adjustable or flexible, movement of the releasable coupling 160 slaves the actuation conduit 153 along the barrel 140 of the pneumatic air excavator 100 (e.g., in an expansion or a retraction movement) and thus the coupling between the actuator assembly 150 and the flow valve 170 via the actuation conduit 153 can be maintained in any position of the actuator assembly 150 relative to the flow valve 170. The locking mechanism 162 of the releasable coupling 160 may be moved to a locked position to secure or lock the releasable coupling 160 to the exterior 141 of the barrel 140.

[0073]In some implementations, the sleeve-shaped portion 161 of the releasable coupling 160 may include the trigger 151 of the actuator assembly 150 coupled thereto, and for instance the trigger 151 may be arranged on or in the sleeve-shaped portion 161 to provide a user with a grippable portion via the sleeve-shaped portion that can be simultaneously used to actuate the actuator assembly 150 via the trigger 151 between an on and off state. In some implementations, the releasable coupling 160 may additionally include a handle 163 (FIGS. 5A and 5B), which may extend from the sleeve-shaped portion 161 and/or may be integrated with the sleeve-shaped portion 161. As shown in FIGS. 5A and 5B, the trigger 151 of the actuator assembly 150 may be integrated with the handle 163 of the releasable coupling 160 and the trigger 151 may be movable between an off position (FIG. 5A) and an on position (FIG. 5B). In some implementations, the handle 163 may be positioned perpendicularly, at an angle, or parallel relative to the releasable coupling 160 and the barrel 140. In addition, the handle 163 may be an adjustable handle that is adjustable to the aforementioned positions. It will be appreciated that the actuator assembly 150 and releasable coupling 160 may be integrated into an assembly configured to be held or gripped by a single hand of the user P to facilitate ergonomics and use of the pneumatic air excavator 100. In further implementations, a second handle 143 (FIG. 2C) may be releasably coupled to the barrel 140 using a second releasable coupling 144, e.g., a cam lock or clamp, and may be configured to be movable to a plurality of locked positions along the length of the barrel 140 independent from the releasable coupling 160.

[0074]In some implementations, a safety mechanism 165 may be included with the air excavator 100 configured to require actuation of primary and secondary actuators for the pneumatic excavator 100 to operate, which actuators may be arranged such that both hands of a user are required for actuation, e.g., by depressing the two actuators using separate hands. This may ensure that the operator always has two hands on the pneumatic excavator 100 during operation and reduces the chances of an accidental discharge. Accordingly, the safety mechanism 165 may include a secondary trigger or actuator 166, which may be operated in combination with the actuator assembly 150 (e.g., the actuation switch or trigger 151) in order for the user to operate of the pneumatic excavator 100. The actuator assembly 150 is also referred to as a primary actuator for purposes of discussion in connection with the secondary actuator 166. Depressing both the primary and secondary actuators 150, 166, respectively, may result in completion of a circuit that enables the flow valve 170 to receive a signal that causes movement to the open position (FIG. 4B) and flow of air through the primary passage 105. In such examples, depressing only one of the primary and secondary actuators 150, 166 may result in the flow valve 170 remaining in a closed position or moving to a closed position (FIG. 4A) for instance due to providing an incomplete circuit, such that the flow valve 170 is held in a closed position and/or is prevented from receiving a signal that otherwise can cause movement to the open position. The safety mechanism 165 may be coupled to the primary actuator 150 via the conduit 153, which may include one or more an air hoses 154d, 154e (FIG. 2B2) and for instance the signal may be an air signal, such as compressed air. Alternatively, the conduit 153 may be configured to carry an electrical signal. The safety mechanism 165 may be arranged along the barrel 140 in a separate location from the actuator assembly 150. In some implementations, a releasable coupling 160′ (FIG. 2A2), e.g., a second releasable coupling, may include the safety mechanism 165 or components thereof integrated therein, and the releasable coupling 160′ may be used to lock the safety mechanism 165 to the barrel 140. For instance, as shown in FIG. 2B2, the actuator 166 of the safety mechanism may be provided on the releasable coupling 160′ and arranged along the barrel 140 in a location separate from the other releasable coupling 160 and the primary actuator 150. Accordingly, the releasable couplings 160, 160′ and their respective trigger 151 and actuator 166 may be movable relative to each other along the length of the barrel 140.

[0075]The flow valve 170 also referred to as a primary valve or main valve of the pneumatic excavator 100 may be arranged between the pipe 114 and the barrel 140 as illustrated in FIGS. 4A and 4B and may be responsible for delivering airflow through the pneumatic air excavator when in the actuated or open position. Referring to FIGS. 3, 4A and 4B, the flow valve 170 may include ports 171a, 171b, 171c, a piston 175, a valve seat 176, an outlet end 178 and an inlet end 179, where the portion of the flow valve 170 defining the primary flow passage 105 extends therebetween. In some implementations the flow valve 170 may be free of a return spring, such as where the flow valve 170 is pneumatically operated, while in other implementations, a mechanical biasing mechanism such as a return spring may be included in the flow valve 170. The flow valve 170 may be configured as a pneumatically piloted valve such as a coaxial valve, a double acting coaxial valve, as a solenoid actuated coaxial valve, as a pneumatic actuated angle seat valve or as a pneumatically actuated ball valve.

[0076]Ports 171a, 171b, and 171c of the flow valve 170 may be coupled to the actuator assembly 150 via the actuation conduit 153. For instance, referring to FIG. 2B1, 2B2 and 3, the actuation conduit 153 may include at least two flexible air hoses, such as three air hoses 154a, 154b, and 154c. Air hose 154a may be configured as a constant pressure conduit, a first end of which may be coupled to the pneumatic air excavator 100 at a port 171a upstream from the piston 175 of the flow valve 170, and the air hose 154a may extend to and be coupled to the actuator assembly 150, e.g., at port 158a, at a second end. Although the port 171a is illustrated as being defined in the flow valve 170, it will be understood that the port 171a may be defined in other portions of the pneumatic excavator 100 upstream from the flow valve 170. The air hose 154a may be constantly supplied compressed air when the delivery line 111 transmits pressurized air. Air hoses 154b, 154c may each be coupled to respective other ports 171b, 171c of the main valve 170 and to respective ports 158b, 158c of the housing 157 of the actuator assembly 150.

[0077]In implementations of use, the pneumatic air excavator 100 may be pneumatically turned on and off using the same compressed air supply that is used to operate the pneumatic air excavator 100. For instance, the actuation conduit 153 may include air hoses, e.g., air hoses 154a, 154b, and 154c. The air hoses may receive compressed air from the delivery line 111 or may carry compressed air emitted from the actuator assembly 150 to the flow valve 170. For instance, the compressed air received by the actuator assembly 150 may be derived from the air supply from the delivery line 111, and thus the actuator assembly 150 may receive the same compressed air supply that is used to operate the pneumatic air excavator 100, e.g., when the flow valve 170 is open and the compressed air passes through the primary flow passage 105.

[0078]In such implementations, actuation of the trigger 151 of the actuator assembly 150 may open a valve of the trigger valve 152, e.g., by movement of a spool against a biasing mechanism such as a return spring, to cause pressurized air from the actuator assembly 150 to enter the actuation conduit 153, e.g., air hose 154c, fluidly coupled to the main valve 170, and the actuation conduit 153 may deliver the pressurized air to a port, e.g., port 171c, of the main valve 170 to cause the main valve 170 to open and thereby permit pressurized air to flow through primary flow passage 105 of the pneumatic air excavator 100. Release of the trigger 151 may cause the trigger valve 152 to relax, for instance as a biasing force is released such as via relaxation of a spring, which may also cause pressurized air from the air supply to enter the actuation conduit 153, e.g., at air hose 154b, and be delivered to the main valve 170, but the pressurized air may be routed to another port, e.g., port 171b of the main valve 170 to close the main valve 170 and thereby prevent pressurized air from flowing through the primary flow passage 105 and exit the nozzle 130. Thus, the actuator assembly and the air hoses of the actuation conduit 153 may be configured to enable the actuator assembly 150 to pneumatically actuate and deactivate the pneumatic air excavator 100.

[0079]In implementations of use where the actuation conduit 153 includes an electrical conduit, the actuation conduit 153 may be configured to electrically actuate the pneumatic air excavator 100 between on and off modes. In examples, actuation of the trigger 151 may cause the trigger valve 152 to send an electrical signal to the flow valve 170 via the actuation conduit 153. When the trigger 151 is actuated, the signal sent by the trigger valve 152 to the flow valve 170 may cause the flow valve 170 to open and thereby permit pressurized air to flow through the primary flow passage 105. When the trigger 151 is released, the signal sent by the trigger valve 152 to the flow valve 170 may cause the flow valve 170 to close and thereby prevent pressurized air from flowing through the flow valve 170 and thus the primary flow passage 105. In some implementations, the flow valve 170 may include an electronic solenoid valve configured to open the flow valve 170 upon receiving the electronic signal from the trigger 151. Thus, the actuation conduit 153 may be configured to enable the actuator assembly 150 to electrically actuate and deactivate the pneumatic air excavator 100.

[0080]In implementations of use, the releasable coupling 160 may be movable along the barrel 140 at various stages of use of the pneumatic air excavator 100. For instance, the releasable coupling 160 may be used to adjust the position of the actuator assembly 150 prior to delivering compressed air through the delivery line 111, however, the releasable coupling 160 may be operated while the compressed air 111 is active. In examples, the trigger 151 of the actuator assembly 150 may be in an open, un-depressed state, the releasable coupling 160 may be unlocked, moved to a selected position, locked to the barrel 140, and then the trigger 151 may be depressed in an excavating operation. In other examples, the trigger 151 may be depressed in connection with an excavating operation while the releasable coupling is unlocked, moved to a new position, and locked to the barrel 140.

[0081]In some implementations of use, at least a portion of the actuator assembly 150 and releasable coupling 160 may be held by one hand of the user P to turn on and off the pneumatic air excavator 100. Due to the releasable coupling 160 being movable, the pneumatic air excavator 100 may be simplified because the user is allowed to select where along the barrel 140 to the actuator assembly 150 should be positioned and operated, for instance, depending on how the pneumatic air excavator 100 is being used or intended to be used, and move the releasable coupling 160 to the selected position. In addition to selecting where the user's hand will be on the air excavator 100 when operating the actuator assembly 150, this flexibility may also facilitate operation due to the ability to adjust and select where the user's other hand is positioned on the pneumatic air excavator 100 relative to the other hand on the actuator assembly 150. Thus, the releasable coupling 160 may provide an ergonomic approach to air excavation and operational control that has not otherwise not been possible.

[0082]According to implementations of use, as shown in the flow diagram of FIG. 6, a method 300 of operating a pneumatic excavator 100 including a movable actuator assembly 150 may involve, in operation 310, adjusting a position of a releasable coupling 160 including the actuator assembly 150 or components thereof, e.g., the trigger 151, along a length of the elongated barrel 140 of the pneumatic excavator 100 such that the flexible actuation conduit 153 is slaved by the adjusting to maintain a communicative coupling between the actuator assembly 150 and the flow valve 170. The method 300 may continue by locking the releasable coupling 160 to the barrel 140 in operation 320. For instance, a clamp of the releasable coupling may be locked to an exterior of the barrel 140. Compressed air may be supplied to an ingress of the flow valve 170 in operation 330. For instance, the compressed air may be supplied via delivery line 111 to the inlet end 179 of the flow valve 170. The actuator may be actuated in operation 340. During such actuation, a signal may be sent to the flow valve 170 to move the flow valve 170 to an open position (FIG. 4B) such that the compressed air at the inlet end 179 of the flow valve 170 is permitted to flow through the flow valve 170, through the primary flow passage 105 and exit the pneumatic excavator via the outlet. Following actuation, the actuator assembly 150 may be released and the actuation conduit may send a signal to the flow valve 170 to move to a closed position to prevent the compressed air from passing through the flow valve (FIG. 4A). Due to the actuation conduit 153 being flexible, the communicative coupling between the actuator assembly 150 and the flow valve 170 may thereby be maintained to enable the actuator assembly 150 to be moved to various locked positions along the barrel 140.

[0083]In the case of the actuation conduit being an air actuation conduit, the delivery line 111 may deliver compressed air to the actuator assembly 150 and to the flow valve 170 via the actuation conduit 153. For instance, prior to actuation of the actuator in operation 340 of method 300, the compressed air supply may be prevented from passing through the barrel 140 and exiting the nozzle 130 due to the flow valve 170 being in a closed position (FIG. 4A), and the piston 175 of the flow valve 170 may seal against a valve seat 176 of the flow valve 170. As provided herein, the air supply from the delivery line 111 may deliver compressed air to the actuator assembly 150, such as via the flexible air hose 154a of the actuation conduit 153 coupled between the flow valve 170 and the actuator assembly 150. More particularly, the air hose 154a may be coupled to the flow valve 170 at a port 171a positioned upstream of the piston 175 such that the compressed air is permitted to constantly pass through the flexible air hose 154a and to the actuator assembly 150 as long as the delivery line 111 is supplied with compressed air. The flexible air hose 154a may thus be configured as a constant pressure conduit that is constantly supplied compressed air. In this initial state of the pneumatic excavator 100 when the compressed air is supplied, the actuation switch of the actuator assembly 150 is in the open position and the compressed air from the air hose 154a is transmitted through the actuator assembly 150 to the flexible air hose 154b of the actuation conduit 153, which in turn transmits the compressed air to the port 171b of the flow valve 170 to force the piston 175 of the flow valve 170 against the valve seat 176 thereof to pneumatically force the flow valve 170 in a closed position, e.g., the compressed air is prevented from passing through the flow valve 170 and the primary flow passage 105.

[0084]Returning to method 300, upon actuating the actuator in operation 340, the actuator assembly 150 may move to a closed position, and compressed air may be transmitted from the actuator assembly 150 through the air hose 154c of the actuation conduit 153, to the flow valve 170 to cause the flow valve 170 to move to an open position (FIG. 4B) where the compressed air from the compressed air supply passes from the delivery line 111 and through the primary flow passage 105 of the pneumatic excavator 100 and exits the nozzle 130. In the open position of the flow valve 170, the piston 175 is pushed away from the valve seat 176 to permit air to pass through.

[0085]Releasing the actuator assembly 150 may result in moving the actuator assembly 150, e.g., the trigger valve 152, back to an initial or normal position, where the actuator assembly 150, e.g., its trigger 151, is in an open position. In this position, the compressed air may be transmitted from the actuator assembly 150 through the actuation conduit 153, e.g., air hose 154b, to the flow valve 170 to cause the flow valve 170 to again move to the closed position (FIG. 4A), where the flow valve 170 prevents the compressed air from passing therethrough, e.g., by the piston 175 of the flow valve 170 again sealing against a valve seat 176 of the flow valve 170.

[0086]In some implementations in which the safety mechanism 165 is included, the primary actuator 150, e.g., the trigger 151 and the safety mechanism 165, e.g., secondary actuator 166, both require actuation or depressing in order for the primary actuator 150 to be actuated. For instance, compressed air may first be received at the secondary actuator 166 and be delivered to the primary actuator 150 such that the compressed air can then be transmitted from the actuator assembly 150 through the air hose 154c, to the flow valve 170 to cause the flow valve 170 to move to the open position (FIG. 4B) as provided herein.

[0087]Accordingly, the actuator assembly 150 alone or the actuator assembly 150 and safety mechanism 165 may together be configured to pneumatically actuate the flow valve 170 via completion of a circuit to the flow valve 170, as provided herein. In addition, as provided herein, the primary actuator 150 and the safety mechanism 165 may be remotely arranged from each other, and from the flow valve 170 as illustrated in the Figures. Where pneumatically actuated, the pneumatic air excavator 100 may provide advantages because use of pressurized air as a means to trigger the flow valve 170 provides an efficient use of pressurized air at the actuator assembly 150 and the safety mechanism 165, when present, where a small air signal may be used, e.g., via the safety mechanism 165 and actuator assembly 150 including the aforementioned conduits, results in a short throw length or relay to cause a large pressure change at the flow valve 170 to cause the flow valve 170 to close and open (FIGS. 4A and 4B). A coaxial-style valve as illustrated in these figures, as well as other pneumatic valves such as ball or angled seat, may thus be operated using a small mechanical operator, like the trigger 151 and secondary actuator 166, to cause pressurized air to flow through the flow valve 170 as provided herein.

[0088]Venting may occur during operation of the compressed air excavator 100 to cause opposing pressure to be vented to the atmosphere. For instance, venting may occur at the actuator assembly 150 and the safety mechanism 165 when present. In some implementations, the flow valve 170 may be vented via one or more ports 171b, 171c when the valve is in the open and/or closed position to facilitate reliable operation of the pneumatic air excavator in the on and off positions. For instance, when the flow valve 170 is in the closed position of FIG. 4A, e.g., due to the compressed air from air hose 154b entering port 171b of the flow valve 170 and forcing the piston 175 against the valve seat 176, any entrapped air present in the port 171c may be vented, for instance through the air hose 154c and to an exhaust port 159a (FIG. 3) of the actuator assembly 150. Similarly, when the flow valve 170 is in the open position of FIG. 4B, e.g., due to the compressed air from the air hose 154c entering port 171c of the flow valve and forcing the piston 175 away from the valve seat 176, any air present in the port 171b may be vented, for instance through the air hose 154b and to the exhaust port 150 of the actuator assembly 150. In addition or alternatively, entrapped air in the main valve 170 received from port 171b may exit this port 171b when the flow valve 170 is moved to an open position, and the entrapped air may be routed through the one of the actuators 166, 150, e.g., through exhaust or vent ports described herein and vented to atmosphere. In some implementations, the flow valve 170 may include a mechanical biasing mechanism such as a return spring to facilitate movement of the piston 175 to the closed position.

[0089]In some implementations, the actuator assemblies and the controller valves may be biased such as spring loaded. For instance, depressing the trigger 151 against a spring force may cause trigger valve 152 to shift from its initial or normal position and the flow valve 170 to move to an open or on position as provided herein. When the trigger 151 is released, the spring relaxes and may cause the trigger valve 152 to shift back to its initial or normal position, which may cause the flow valve 170 to move to the closed or off position as provided herein.

[0090]FIGS. 7A and 7B illustrate circuit diagrams of pneumatic actuation of the pneumatic excavator 100, according to implementations of the present disclosure.

[0091]With reference to FIG. 7A, in the open position of trigger 151 (e.g., in an unactuated state), pressurized air is routed from the actuator assembly 150 to the air hose 154b, which extends to the flow valve 170, e.g., to the primary valve, port 171b such that the compressed air maintains and/or forces the flow valve 170 to the closed position as shown in FIG. 7A, e.g., the piston 175 remains seated in the valve seat 176 (FIG. 4A) such that no compressed air flows through the primary flow passage 105 of the pneumatic air excavator 100. Any entrapped air present in the port 171c may be vented through the air hose 154c to an exhaust port 159a of the actuator assembly 150.

[0092]With reference to FIG. 7B, when the trigger 151 of the actuator assembly 150 is pressed, the trigger valve 152, e.g., the spool of a spool valve, shifts and the compressed air is no longer delivered to the air hose 154b. In this state of the trigger 151 and the trigger valve 152, the constant pressure delivered to the actuator assembly 150 is then directed to the air hose 154c to deliver compressed air to the port 171c of the flow valve 170 to open the flow valve 170 as shown in FIG. 7B, e.g., the piston 175 is pushed away from the valve seat 176 to thereby move the flow valve 170 to the open position (FIG. 4B) such that compressed air flows through the primary flow passage 105 and exits the nozzle 130. At the time of depressing the trigger 151 pressure keeping the flow valve 170 shut is released or vented from the air hose 154b. For instance, any entrapped air present in the port 171b may be vented through the air hose 154b and to the exhaust port 159b of the actuator assembly 150.

[0093]As described herein, the air hose 154a may be connected upstream of the flow valve 170 and may constantly receive an air signal, e.g., may be constantly pressurized and be a constant pressure conduit of the actuator assembly 150. In the open position of trigger 151 (e.g., in an unactuated state), pressurized air is routed from the actuator assembly 150 to the air hose 154b, which extends to the flow valve 170, e.g., to the primary valve, port 171b such that the compressed air maintains and/or forces the flow valve 170 to the closed position as shown in FIG. 4A, e.g., the piston 175 remains seated in the valve seat 176 such that no compressed air flows through the primary flow passage 105 of the pneumatic air excavator 100. Accordingly, the constant supply of compressed air may be constantly delivered to one of the ports 171b or 171c of the flow valve 170. In some implementations, the flow valve 170 is a pneumatic valve requiring the delivery of the compressed air to one of its ports 171b and 171c in order to open and close, and accordingly the flow valve 170 may be free of a biasing mechanism such as a return spring.

[0094]According to implementations of use, as illustrated in FIG. 8, a method 400 of pneumatically actuating the pneumatic excavator 100 may involve supplying compressed air to the pneumatic excavator 100 from a compressed air supply in operation 410, e.g., via the delivery line 111 coupled to an air compressor truck. Initially, the compressed air supply is prevented from passing through the barrel 140 and exiting the nozzle 130 due to the flow valve 170 being in a closed position (FIGS. 4A, 7A), and for instance, the piston 175 of the flow valve 170 may seal against a valve seat 176 of the flow valve 170. As provided herein, the air supply from the delivery line 111 may deliver compressed air to the actuator assembly 150, such as via the flexible air hose 154a of the actuation conduit 153 coupled between the flow valve 170 and the actuator assembly 150. More particularly, the air hose 154a may be coupled to the flow valve 170 at a port 171a positioned upstream of the piston 175 such that the compressed air is permitted to constantly pass through the flexible air hose 154a and to the actuator assembly 150 as long as the delivery line 111 is supplied with compressed air. The flexible air hose 154a may thus be configured as a constant pressure conduit that is constantly supplied compressed air. In this initial state of the pneumatic excavator 100 with the supply of compressed air, the actuation switch of the actuator assembly 150 is in the open position and the compressed air from the flexible air hose 154a is transmitted through the actuator assembly 150 to the air hose 154b of the actuation conduit 153, which in turn transmits the compressed air to the port 171b of the flow valve 170 to force the piston 175 of the flow valve 170 against the valve seat 176 thereof to pneumatically force the flow valve 170 in a closed position or retain the flow valve 170 in the closed position, e.g., the compressed air is prevented from passing through the flow valve 170 and the primary flow passage 105.

[0095]The method 400 may continue by actuating the actuator assembly 150 in operation 420 by moving the actuation switch, e.g., by depressing the trigger 151. When the actuation switch is actuated, e.g., in the closed position, compressed air is transmitted from the actuator assembly 150 through the air hose 154c of the actuation conduit 153, to the flow valve 170 to cause the flow valve 170 to move to an open position (FIGS. 4B, 6B) where the compressed air from the compressed air supply passes from the delivery line 111 and through the primary flow passage 105 of the pneumatic excavator 100 and exit the nozzle 130. In the open position of the flow valve 170, the piston 175 is pushed away from the valve seat 176 to permit air to pass through. For instance, the trigger valve 152 may include a spool valve with a spool and spool pilot, and the spool is biased by a biasing mechanism such as a spring or solenoid valve. When the trigger 151 is depressed, the spool may move against the bias force of the biasing mechanism.

[0096]The method 400 may proceed by releasing the actuator assembly 150 in operation 430 by moving the actuation switch to an open position, e.g., by releasing the trigger 151. For instance, release or deactivation may cause the trigger 151 to move under the force of the biasing mechanism as it moves to the unbiased state, e.g., to a normal position. More particularly, a spool of the trigger valve 152 may shift to a normal position, which may force the trigger 151 to an open or unactuated position. When the actuation switch is in the open position, the compressed air may be transmitted from the actuator assembly 150 through the actuation conduit 153, e.g., air hose 154b, to the flow valve 170 to cause the flow valve 170 to again move to the closed position (FIGS. 4A, 7A), where the flow valve 170 prevents the compressed air from passing therethrough, e.g., by the piston 175 of the flow valve 170 again sealing against a valve seat 176 of the flow valve 170.

[0097]In some implementations, the flow valve 170 may be vented via one or more ports 171b, 171c when the valve is in the open and/or closed position to facilitate reliable operation of the pneumatic air excavator in the on and off positions. For instance, when the flow valve 170 is in the closed position of FIG. 7A, e.g., due to the compressed air from air hose 154b entering port 171b of the flow valve 170 and forcing the piston 175 against the valve seat 176, any entrapped air present in the port 171c may be vented, for instance through the air hose 154c and to an exhaust port 159a (FIG. 7A) of the actuator assembly 150. Similarly, when the flow valve 170 is in the open position of FIG. 7B, e.g., due to the compressed air from the air hose 154c entering port 171c of the flow valve and forcing the piston 175 away from the valve seat 176, any entrapped air present in the port 171b may be vented, for instance through the air hose 154b and to the exhaust port 159b of the actuator assembly 150.

[0098]Due to the actuator assembly 150 being configured to pneumatically actuate the flow valve 170 via the actuation conduit 153, e.g., being configured as an air actuation conduit, the actuator assembly 150 may be remotely arranged from the flow valve 170 as illustrated in the Figures. However, the actuator assembly 150 and its actuation conduit 153 may also be arranged on or integrated with the flow valve 170 while not departing from the other advantageous features of the pneumatic air excavator 100 of the present disclosure.

[0099]Pneumatically actuating the pneumatic air excavator 100 may provide advantages because use of pressurized air as a means to trigger the flow valve 170 provides an efficient use of pressurized air at the actuator assembly 150 where a small air signal may be used, e.g., via the actuator assembly 150 including the actuation conduit 153, results in a short throw length or relay to cause a large pressure change at the flow valve 170 to cause the flow valve 170 to open and close (FIGS. 4A and 4B). A coaxial-style valve as illustrated in these figures, as well as other pneumatic valves such as ball or angled seat, may thus be operated using a small mechanical operator, like the trigger 151, to open the trigger valve 152 of the actuator assembly 150 to cause pressurized air to flow through the actuation conduit 153 to operate the flow valve 170 as provided herein.

[0100]Venting may occur during operation of the compressed air excavator 100 to cause opposing pressure to be vented to the atmosphere. For instance, during movement of compressed air through the primary flow passage 105, e.g., while the piston 175 is separated from the valve seat 176, the opposing pressure directed against the piston 175 may be released and discharged or vented through the port 171b (FIG. 4B), may proceed through the air hose 154b and be exhausted through the exhaust port 159a at the actuator assembly 150. Once the trigger 151 is released, the pressure keeping the flow valve 170 open is released from the air hose 154c, e.g., the air is vented to atmosphere such as via an exhaust port 159b of the actuator assembly 150, and the compressed air is delivered from the actuator assembly 150 back to the air hose 154b such that the compressed air forces the piston 175 against the valve seat 176 to seal the flow valve 170 in a closed position. In some implementations, the flow valve 170 may include a mechanical biasing mechanism such as a return spring to facilitate movement of the piston 175 to the closed position.

[0101]In some implementations, the actuator assemblies may be biased such as spring loaded. For instance, depressing the trigger 151 against a spring force may cause trigger valve 152 to shift from its initial or normal position and the flow valve 170 to move to an open or on position as provided herein. When the trigger 151 is released, the spring relaxes and may cause the trigger valve 152 to shift back to its initial or normal position, which may cause the flow valve 170 to move to the closed or off position as provided herein. In other implementations, one or more actuators or valves of the pneumatic air excavator 100, e.g., of the actuator assembly and/or the controller, may be biased by a solenoid valve.

[0102]With reference to FIGS. 9A-9C, the pneumatic excavator 100 may include the safety mechanism 165 configured to receive an air signal such as compressed air. In this case, the secondary actuator 166 may be configured as a valve for receiving and transmitting compressed air, such as a spool valve. The secondary actuator 166 may be actuated, for instance, using a trigger of the secondary actuator 166. The secondary actuator may be fluidly coupled to at least one air conduit. For instance, the actuator 166 may include an intake port 168a configured to constantly receive compressed air, such as from a constant pressure conduit 154a′ configured to receive compressed air from a port upstream of the flow valve 170, and may be configured with a delivery port 168b for coupling via an air delivery conduit 169 to a shuttle valve 167a, as well as another delivery port 168c for coupling via an air delivery conduit to an intake port 150a the primary actuator 150. For instance, the air hose 154d may be configured as a constant pressure conduit configured to conditionally receive an air signal from the constant pressure conduit 154a′ such as when the secondary actuator 166 is in an actuated or closed position.

[0103]FIG. 9A illustrates an initial state of the secondary actuator 166 of the safety mechanism 165 prior to actuation, such as in a normal position of the secondary actuator 166 configured as a valve spool biased by a biasing mechanism. In the initial state, the pressure signal entering the secondary actuator 166 may be routed into the shuttle valve 167a. The shuttle valve 167a may include an entry or intake port on each side 167b, 167c, and a separate exit or delivery port 167d, e.g., on the bottom. The shuttle valve 167a may allow air flow through the entry port with the higher pressure, and blocks the entry of air flow into the entry port having the lower pressure. In FIG. 9A, the intake port 167b of the shuttle valve is pressurized via air delivery conduit 169, e.g., an air hose, and the intake port 167c is vented back to atmosphere at this phase via, flow is allowed from the intake port 167b to the exit port 167d and the intake port 167c is blocked-off. The pressure signal from the exit port 167d of the shuttle valve 167a is directed into the port 171b of the main valve 170, ensuring that the main valve 170 remains shut while both actuators 166, 150 are in the initial state or normal position. The shuttle valve 167a may prevent the pressure signal from the secondary actuator 166 from looping back through primary actuator 150 and venting to atmosphere. At this phase, if the primary actuator 150 was actuated but not the secondary actuator 166, no change would occur since no pressure signal is provided at the intake port 150a of the actuator 150. In addition, any entrapped air at the port 171c of the main valve 170 may be vented through vent port 159a of the actuator assembly 150 via the air hose 154c.

[0104]With reference to FIG. 9B, once the secondary actuator 166 is actuated, e.g., depressed, the pressure signal may instead be routed into the entry or intake port 150a of the primary actuator 150 for instance via a conduit or air hose 154d configured to conditionally receive an air signal from the constant pressure conduit 154a′ when the secondary actuator 166 is actuated. In the state of FIG. 9B, the conduit 154d may also function as a constant pressure conduit by receiving a constant supply of compressed air when the delivery line 111 is transmitting pressurized air to the pneumatic excavator 100. If the primary actuator 150 is in the initial or normal position, then the pressure signal may be routed into the shuttle valve 167a. At this phase the intake port 167b of the shuttle valve is routed to atmosphere, so the pressure signal at the other intake port 167c is passed to the exit or delivery port 167d, and the intake port 167b is blocked. Again, the pressure signal at the exit port 167d may be routed to the port 171b of the main valve 170, ensuring that the main valve 170 remains shut even if one of the two actuators is depressed. In addition, any entrapped air at the port 171c of the main valve 170 may be vented through vent port 159a of the actuator assembly 150 via the air hose 154c.

[0105]With reference to FIG. 9C, a next phase of operation is illustrated when both the primary and secondary actuators 150, 166 are actuated. With the secondary actuator 166 depressed the air signal is routed into the entry or intake port 150a of the actuator 150. With the actuator 150 actuated, e.g., the trigger 151 depressed, the air signal may then be routed into the port 171c of the main valve 170 thereby forcing the main valve 170 into an open position. Entrapped air in the main valve 170 received from port 171b may then exit this port 171b and be routed through the shuttle valve 167a and vented through one of the actuators 166, 150, e.g., at vent port 159b of the primary actuator 150 and vented to atmosphere.

[0106]According to implementations of use, as shown in the flow diagram of FIG. 10, a method 500 of operating a pneumatic excavator 100 including a safety mechanism 165 may involve, in operation 510, supplying compressed air to the pneumatic excavator 100 from a compressed air supply, e.g., via delivery line 111. The method 500 may continue by actuating the primary actuator 150 and the secondary actuator 166 of the safety mechanism 165 in operation 520 to cause compressed air to be transmitted from the secondary actuator 166 to the primary actuator 150 and then to the flow valve 170 to cause the flow valve 170 to move to an open position (FIG. 4B) such that the compressed air from the supply of compressed air passes through the primary flow passage 105 and exits the pneumatic excavator 100. Actuating one of the primary or secondary actuators 150, 166 and not actuating the other in operation 530 may cause the compressed air to be transmitted to the shuttle valve 167a to the flow valve 170 to cause the flow valve 170 to move to a closed position (FIG. 4A) such that the compressed air from the supply of compressed air is prevented from passing through the flow valve 170.

[0107]For instance, in operation 510, the compressed air may be supplied via delivery line 111 to the inlet end 179 of the flow valve 170 such that the compressed air enters the constant pressure conduit 154a′ and is received by an intake port of the secondary actuator 166 of the safety mechanism 165.

[0108]Prior to actuation of the actuators in operation 520 of method 500, the compressed air supply may be prevented from passing through the barrel 140 and exiting the nozzle 130 due to the flow valve 170 being in a closed position (FIG. 4A) and the primary or secondary actuator 150, 166 routing pressurized air to the shuttle valve 167a, which transmits the compressed air to the flow valve 170 to retain or move the piston 175 to seal against a valve seat 176 of the flow valve 170 (FIG. 4A). For instance, the constant pressure conduit 154a′ may receive the compressed air from the port 171a positioned upstream of the piston 175 such that the compressed air is permitted to constantly pass through the constant pressure conduit 154a′ and to the secondary actuator 166 as long as the delivery line 111 is supplied with compressed air. Where the secondary actuator 166 is open, e.g., unactuated, the compressed air is routed from the secondary actuator 166 to the port 171b of the flow valve 170 via the exit port 167d of the shuttle valve 167a to close or retain the flow valve 170 in a closed position. Where the secondary actuator 166 is closed, e.g., actuated, but the primary actuator 150 is open, e.g., unactuated, the compressed air is received at the primary actuator 150 from the air hose 154d, e.g., configured as a conditional constant pressure conduit, but again is routed to the port 171b of the flow valve 170 via the exit port 167d of the shuttle valve 167a, to again close or retain the flow valve in the closed position. Thus, the pneumatic excavator 100 is provided with a safety mechanism permitting operation, e.g., air flow through the primary flow path 105, only when both actuators are actuated.

[0109]Returning to method 500, upon actuating the primary actuator 150 and the secondary actuator 166 in operation 520, the actuator assemblies may each move to a closed position, and compressed air may be transmitted from the constant pressure conduit 154a′, air hose 154d and through the air hose 154c of the actuation conduit 153, to the flow valve 170 to cause the flow valve 170 to move to an open position (FIG. 4B) where the compressed air from the compressed air supply passes from the delivery line 111 and through the primary flow passage 105 of the pneumatic excavator 100 and exits the nozzle 130. In the open position of the flow valve 170, the piston 175 is pushed away from the valve seat 176 to permit air to pass through. In this state of the actuators 150, 166, the shuttle valve 167a may not receive compressed air. For instance, when both actuators 150, 166 are first depressed and the piston 175 shifts to the open position there may be an initial venting of air from port 171b, which may exit shuttle valve 171a and to atmosphere. After this initial venting the shuttle valve 171a may remain open to atmosphere on both intake ports until one or both of the actuators 150, 166, e.g., triggers 151 and/or trigger of the secondary actuator 166, has been released.

[0110]Releasing one or the other primary or secondary actuator 150, 166, e.g., while keeping the other actuated in operation 530, may result in the airflow from the constant pressure conduit 154a′ being routed to the shuttle valve 167a to thereby cause the flow valve 170 to again move to the closed position (FIG. 4A). For instance, during the actuating of one of the primary actuator 150 or the secondary actuator 166 and not actuating the other, the shuttle valve 167a allows air to enter one entry port 167b or 167c from the actuated actuator and prevents air from entering the other entry port. In some implementations, the flow valve 170 is a pneumatic valve requiring the delivery of compressed air to one of its ports 171b and 171c in order to open and close, and accordingly the flow valve 170 may be free of a biasing mechanism such as a return spring.

[0111]Accordingly, the actuator assembly 150 and safety mechanism 165 may together be configured to pneumatically actuate the flow valve 170 via completion of an air circuit from the constant pressure conduit 154a′ to the flow valve 170 via the air hose 154d and the air hose 154c, as provided herein. In addition, as provided herein, the actuator 150 and the safety mechanism 165 may be remotely arranged from each other and from the flow valve 170 as illustrated in the Figures. Pneumatically actuating the pneumatic air excavator 100 may provide advantages because use of pressurized air as a means to trigger the flow valve 170 provides an efficient use of pressurized air at the safety mechanism 165 and the actuator assembly 150 where a small air signal may be used, e.g., via the safety mechanism 165 and actuator assembly 150 including the aforementioned conduits, results in a short throw length or relay to cause a large pressure change at the flow valve 170 to cause the flow valve 170 to close and open (FIGS. 4A and 4B). A coaxial-style valve as illustrated in these figures, as well as other pneumatic valves such as ball or angled seat, may thus be operated using a small mechanical operator, like the trigger 151 and secondary actuator 166, to cause pressurized air to flow through the flow valve 170 as provided herein.

[0112]Venting may occur during operation of the compressed air excavator 100 to cause opposing pressure to be vented to the atmosphere. In some implementations, the flow valve 170 may be vented via one or more ports 171b, 171c when the valve is in the open and/or closed position to facilitate reliable operation of the pneumatic air excavator in the on and off positions. For instance, when the flow valve 170 is in the closed position of FIG. 4A, e.g., due to the compressed air from air hose 154b entering port 171b of the flow valve 170 and forcing the piston 175 against the valve seat 176, any entrapped air present in the port 171c may be vented, for instance through the air hose 154c and to an exhaust port 159a (FIG. 3) of the actuator assembly 150. Similarly, when the flow valve 170 is in the open position of FIG. 4B, e.g., due to the compressed air from the air hose 154c entering port 171c of the flow valve and forcing the piston 175 away from the valve seat 176, any air present in the port 171b may be vented, for instance through the air hose 154b and to the exhaust port 150 of the actuator assembly 150. In addition or alternatively, entrapped air in the main valve 170 received from port 171b may exit this port 171b when the flow valve 170 is moved to an open position, and the entrapped air may be routed through the one of the actuators 166, 150, e.g., through exhaust or vent ports described herein and vented to atmosphere. In some implementations, the flow valve 170 may include a mechanical biasing mechanism such as a return spring to facilitate movement of the piston 175 to the closed position.

[0113]In some implementations, the actuator assemblies and the controller valves may be biased such as spring loaded. For instance, depressing the trigger 151 against a spring force may cause trigger valve 152 to shift from its initial or normal position and the flow valve 170 to move to an open or on position as provided herein. When the trigger 151 is released, the spring relaxes and may cause the trigger valve 152 to shift back to its initial or normal position, which may cause the flow valve 170 to move to the closed or off position as provided herein.

[0114]With reference to FIGS. 11A-11F, as well as FIGS. 3, 4A and 4B, the controller valve 180 is provided for controlling flow modes of the pneumatic excavator 100 when the actuator assembly 150 is actuated. The controller valve 180 may provide a fluid coupling between the actuator assembly and the flow valve 170, and for instance may be coupled to the actuator assembly 150 via the actuation conduit 153 and to the flow valve 170 at ports 171b and 171c, such as via exit ports of the controller valve 180 or via air conduits. The controller valve 180 may for instance include a selector to permit different flow modes of compressed air to be delivered through the nozzle 130, such as a pulsed flow of compressed air and a constant flow of compressed air. A pulsed compressed air mode may deliver a pulsed, sinusoidal wave-type of airflow through the nozzle 130, where peaks of the pulsed compressed air provide a higher impact impingement relative to a constant flow of compressed air. Delivery of pulsed compressed air may facilitate breaking up of compact materials and may additionally promote the use of less air in excavation operations. The sinusoidal nature of the pulsed air may also provide the advantage instantaneously delivering a greater flow of air than what the air supply or compressor is capable of outputting at a steady state. A constant flow mode of the controller valve 180 may result in compressed air being delivered constantly through the nozzle 130, e.g., in a smooth stream. The controller valve 180 may be pneumatically driven and may be fluidly coupled to the actuator assembly 150 and to the flow valve 170. Alternatively, the controller valve 180 may be configured as or include an electrical solenoid valve and may be electrically coupled to the actuator assembly 150 and the flow valve 170.

[0115]The controller valve 180 may include a selector switch 181 for the user P to select the flow mode from the controller valve 180; an adjustment device 182 for adjusting a frequency of pulsing when a pulsed flow mode is selected; a spool pilot 183; a pulse control line 184, e.g., a direct impingement line, configured as an air conduit that may extend between the controller valve 180, e.g., a selector switch 181 and a port 105a of the primary flow passage 105 (e.g., along the barrel 140) downstream from the flow valve 170 egress, and may be coupled to the adjustment device 182, as shown in FIG. 3; ports 185a, 185b, 185c, which may respectively be coupled to the pulse control line 184, the air hose 154b, and the air hose 154c; and exhaust ports 186, 189.

[0116]As described herein, the air hose 154a may be connected upstream of the flow valve 170 and constantly receive an air signal, e.g., may be constantly pressurized and be a constant pressure conduit of the actuator assembly 150. With reference to FIG. 11A, in the open position of trigger 151 (e.g., in an unactuated state), pressurized air is routed from the actuator assembly 150 to the air hose 154b, which extends to the controller valve 180 and to the flow valve 170, e.g., to the primary valve, port 171b such that the compressed air maintains and/or forces the flow valve 170 to the closed position as shown in FIG. 4A, e.g., the piston 175 remains seated in the valve seat 176 such that no compressed air flows through the primary flow passage 105 of the pneumatic air excavator 100.

[0117]When the trigger 151 of the actuator assembly 150 is pressed, the trigger valve 152, e.g., the spool of a spool valve, shifts and the compressed air is no longer delivered to the air hose 154b, and the pressure keeping the flow valve 170 shut is released or vented from the air hose 154b. In this state of the trigger 151, the constant pressure delivered to the actuator assembly 150 may then be directed to the air hose 154c to deliver compressed air to the controller valve 180 and into the port 171c of the flow valve 170 to push the piston 175 away from the valve seat 176 to thereby move the flow valve 170 to the open position as shown in FIG. 4B such that compressed air flows through the primary flow passage 105 and exits the nozzle 130.

[0118]During such operation of the actuator assembly 150, e.g., while air flows through the primary flow passage 105, then the selector switch 181 of the controller valve 180 can become functional and be operated to select an operational mode such as a pulse mode or a constant flow mode. When the switch is in, or moved to, the constant flow mode selection, the compressed air from the air hose 154c is directed from the controller valve 180 to the port 171c of the flow valve 170 such that the flow valve 170 is maintained in an open position to allow the compressed air from the delivery line 111 to constantly flow through the primary flow passage 105 and exit the nozzle 130 as shown in FIG. 4B.

[0119]With reference to FIG. 11B, when the switch 181 is moved to the pulse mode selection, and again while the trigger valve 152 is shifted by the trigger 151, the constant pressure delivered to the actuator assembly 150 is directed to the air hose 154c then to the port 171c of the flow valve 170 to push the piston 175 away from the valve seat 176 to thereby move the flow valve 170 to the open position as shown in FIGS. 11B and 4B such that compressed air flows through the primary flow passage 105 and exits the nozzle 130. In the pulse mode selection position, the pulse control line 184 is open but initially has not yet been pressurized, and consequently, the flow valve 170 remains open. At the same time, due to the flow valve 170 being open, entrapped air at the valve port 171b is forced out to atmosphere through the port 159b of the actuator assembly 150.

[0120]With reference to FIG. 11C, and again while the switch 181 is in the pulse mode selection with the trigger valve 152 shifted by the trigger 151, because pulse control line 184 is opened, the compressed air flow passing through the primary flow path 105 at an outlet side 178 of the flow valve 170, e.g., in the barrel 140, begins to cause the pulse control line 184 to be pressurized. This pressure or air flow fills the pulse control line 184, which air signal passes through the adjustment device 182, e.g., pneumatic speed controller or flow controller such as a needle valve, which throttles flow depending upon how far open or closed they are, and the selector switch 181, e.g., toggle valve, and then into the spool pilot 183 of the controller valve 180. With the spool pilot 183 pressurized a spool within the controller valve 180 shifts, e.g., to an actuated position, and changes the flow paths within the controller valve 180. With the flow paths shifted, the pressure signal from the actuator assembly 150 from the air hose 154c, is now directed to the port 171b of the flow valve 170 to close the flow valve 170, and the port 171c of the flow valve 170 is vented to atmosphere, e.g., via an exhaust port 189 of the controller valve 180. This shuts the flow valve 170 and cuts-off flow to the barrel 140. The adjustment device 182 in line with the pulse control line 184 regulates the amount of air that can pass through, which in turn regulates how quickly the spool pilot 183 is able to pressurize and thereby shift the spool to change flow paths. By reducing the amount flow through the adjustment device 182 the frequency of pulses can effectively be slowed down, or inversely sped up by allowing more air through.

[0121]With reference to FIG. 11D, once the flow valve 170 has been shut, no more air enters the barrel 140 and the pressure therein returns to atmospheric. With the barrel 140 now unpressurized, the spool pilot 183 of the controller valve 180 also loses pressure. With the spool pilot 183 no longer pressurized a biasing mechanism, e.g., a spring, of the controller valve 180 may return the spool of the controller valve 180, to its normal or unactuated position and shift the flow path. Once again, the pressure signal from the actuator assembly 150 is directed into the port 171c of the flow valve 170 forcing the flow valve 170 open and allowing the compressed air to flow through the primary flow path 105. The process of pressurizing the pulse control line 184 and the steps described in connection with FIG. 11C then repeat, resulting in an automatic pulsing function of the controller valve 180. Thus, due to the spool of the controller valve 180 moving in a reciprocating manner when the trigger 151 is actuated and the switch 181 is in the pulse mode selection, this results in a pulsed compressed airflow being delivered from the pneumatic air excavator 100. The pulsing loop of the controller valve 180 may continue until the actuator assembly 150 is released from being actuated, or until the switch 181, e.g., inline toggle switch, is moved a constant flow mode, for instance as described in connection with FIG. 11F.

[0122]With reference to FIG. 11E, once the actuator assembly 150 has been released, e.g., the trigger 151 is no longer pressed and the trigger valve 152 shifts to its normal position or open position, the flow valve 170 may return to its closed position due to pressurized air from the air hose 154b entering port 171b and forcing the piston 175 against the valve seat 176 to close the valve 170 to thereby discontinue flow through the primary flow passage 105.

[0123]With reference to FIG. 11F, details of the controller valve 180 pulse toggle function are provided, according to implementations of the present disclosure. The purpose of the pulse toggle switch, e.g., switch 181, is to allow the air excavator 100 to operate in either a constant flow or pulsed flow mode as described herein. FIG. 11F represents a pneumatic circuit when the actuator 150 is being depressed, but the pulse toggle switch is in the constant flow position. In this position the pulse toggle switch blocks flow to the spool pilot 183 of the controller valve 180. For instance, the pulse toggle switch 181 may prevent pressure from continuing on through the pulse control line 184 to pressurize the spool pilot 183. Since the spool pilot 183 does not receive a pressure signal it remains in the normal position, meaning that the main valve or flow valve 170 will remain open as long as the trigger valve 152 is depressed to permit airflow through the primary flow passage 105, and the flow valve 170 will close when the trigger valve is released 152. With the pulse toggle switch in the position of FIG. 11F, an exhaust port 186 of the switch 181 may also allow any pressure that is contained within the spool pilot 183 to be vented to atmosphere, via the exhaust port 186 of the switch 181, e.g., through the entry port 185a of the spool pilot 183 (this instance is unlikely and could only occur if the pulse toggle switch was toggled from pulse to constant while the gun was in the phase of operation of FIG. 11C).

[0124]According to implementations of use, as shown in the flow diagram of FIG. 12, a method 600 of delivering pulsed compressed air through a pneumatic excavator may involve constantly supplying compressed air to the pneumatic excavator 100 from a compressed air supply in operation 610, e.g., via the delivery line 111 coupled to a compressor truck. Initially, the compressed air supply is prevented from passing through the barrel 140 and exiting the nozzle 130 due to the flow valve 170 being in a closed position (FIGS. 4A, 11A), and for instance, the piston 175 of the flow valve 170 may seal against a valve seat 176 of the flow valve 170. As provided herein, the air supply from the delivery line 111 may deliver compressed air to the actuator assembly 150, such as via the flexible air hose 154a of the actuation conduit 153 coupled between the flow valve 170 and the actuator assembly 150. More particularly, the air hose 154a may be fluidly coupled to the flow valve 170 at a port 171a positioned upstream of the piston 175 such that the compressed air is permitted to constantly pass through the flexible air hose 154a and to the actuator assembly 150 as long as the delivery line 111 is supplied with compressed air. The air hose 154a may thus be configured as a constant pressure conduit that is constantly supplied compressed air. In this initial state of the pneumatic excavator 100 when the compressed air is supplied, the actuation switch of the actuator assembly 150 is in the open position and the compressed air from the flexible air hose 154a is transmitted through the actuator assembly 150 to the air hose 154b of the actuation conduit 153, which in turn transmits the compressed air to port 185b of the controller valve 180 fluidly coupled to the port 171b of the flow valve 170 to force the piston 175 of the flow valve 170 against the valve seat 176 thereof to pneumatically force the flow valve 170 in a closed position (FIG. 11A), e.g., the compressed air is prevented from passing through the flow valve 170 and the primary flow passage 105.

[0125]The method 600 may continue by actuating the actuator assembly 150 to operate the controller valve 180 and cause the flow valve 170 to deliver pulsed compressed air in operation 620, for instance by moving the actuation switch, e.g., by depressing the trigger 151, while the switch 181 of the controller valve 180 is in the pulse mode position. Operation 620 proceeds in phases to deliver the pulsed compressed air. Initially, in a first phase of actuation, a first portion of compressed air is delivered to the flow valve 170 via the controller valve 180 to move the flow valve 170 to the open position (FIGS. 4B, 11B), e.g., by delivering compressed air from the port 185c of the controller valve to the port 171c of the flow valve to separate the piston 175 from the valve seat 176, and, as a result, a second portion of compressed air passes through the primary flow passage 105 by flowing through the flow valve 170 ingress and egress, through the barrel 140 and exiting the outlet thereof. In a second phase of actuation, the pulse control line 184 of the controller valve 170 is pressurized by the second portion of the compressed air passing through the primary flow passage 105, which causes the spool pilot 183 of the controller valve 180 to be pressurized, and which shifts the controller valve 180 to an actuated position to cause the compressed air to be delivered from port 185b to port 171c of the flow valve 170 such that the flow valve 170 moves to a closed position (FIG. 11C) and prevents the second portion of compressed air from passing through the flow valve 170, e.g., the egress thereof. For instance, the controller valve 180 may include a spool pilot 183 that is pressurized and causes a spool to move to the actuated position, which may be against the force of a biasing mechanism. In a third phase of actuation, due to the flow valve 170 being closed, the pulse control line 184 and the controller valve 180 are no longer pressurized and the controller valve 180 shifts to an unactuated position to thereby permit the second portion of compressed air to pass through the primary flow passage 105 (FIG. 11D) and again pressurize the pulse control line 184 to then repeat the first and second phases, whereby pulsed compressed air is delivered through the primary flow passage of the pneumatic excavator. In the case of a spool, the lack of pressurization in the spool pilot results in the spool returning to its normal position as the biasing mechanism, e.g., return spring, relaxes.

[0126]When the actuator is released, e.g., not actuated, the first portion of compressed air is transmitted from the actuator 150 to the flow valve 170 via the controller valve 180 such that the first portion of compressed air holds the piston 175 of the flow valve 170 in the closed position (FIG. 11E). When the selector switch 181 is moved to a constant flow mode, the controller valve 180 or portion thereof, e.g., spool and spool pilot, may be inactive and may not receive a pressure signal when the actuator 150 is actuated. For instance, when the constant flow mode of operation is selected, the pulse control line and the spool pilot are inactivated and the first portion of compressed air holds the piston in the open position during actuation of the actuator 150 to thereby open the flow valve 170 and permit the second portion of compressed air to pass therethrough and through the primary flow passage 105. In some implementations, the flow valve 170 is a pneumatic valve requiring the delivery of compressed air to one of its ports 171b and 171c in order to open and close, and accordingly the flow valve 170 may be free of a biasing mechanism such as a return spring.

[0127]Due to the actuator assembly 150 being configured to pneumatically actuate the flow valve 170 via the actuation conduit 153, e.g., being configured as an air actuation conduit, the actuator assembly 150 may be remotely arranged from the flow valve 170 as illustrated in the Figures. However, the actuator assembly 150 and its actuation conduit 153 may also be arranged on or integrated with the flow valve 170 while not departing from the other advantageous features of the pneumatic air excavator 100 of the present disclosure.

[0128]Pneumatically actuating the pneumatic excavator 100 may provide advantages because use of pressurized air as a means to trigger the flow valve 170 provides an efficient use of pressurized air at the actuator assembly 150 where a small air signal may be used, e.g., via the actuator assembly 150 including the actuation conduit 153, results in a short throw length or relay to cause a large pressure change at the flow valve 170 to cause the flow valve 170 to open and close (FIGS. 11A-11F). A coaxial-style valve as illustrated in these figures, as well as other pneumatic valves such as ball or angled seat, may thus be operated using a small mechanical operator, like the trigger 151, to open the trigger valve 152 of the actuator assembly 150 to cause pressurized air to flow through the actuation conduit 153 to operate the flow valve 170 as provided herein.

[0129]Venting may occur during operation of the compressed air excavator 100 to cause opposing pressure to be vented to the atmosphere. For instance, during movement of compressed air through the primary flow passage 105, e.g., while the piston 175 is separated from the valve seat 176, the opposing pressure directed against the piston 175 may be released and discharged or vented through the port 171b (FIG. 4B), may proceed through the air hose 154b and be exhausted through the exhaust port 159a at the actuator assembly 150. Once the trigger 151 is released, the pressure keeping the flow valve 170 open is released from the air hose 154c, e.g., the air is vented to atmosphere such as via an exhaust port 159b of the actuator assembly 150, and the compressed air is delivered from the actuator assembly 150 back to the air hose 154b such that the compressed air forces the piston 175 against the valve seat 176 to seal the flow valve 170 in a closed position. In some implementations, the flow valve 170 may include a mechanical biasing mechanism such as a return spring to facilitate movement of the piston 175 to the closed position. In addition, venting may occur at the controller valve 180 via the exhaust port 189 when the spool of the controller valve 180 shifts the flow paths such that the pressure signal from the air hose 154c is shifted to the port 171b of the flow valve 170 that closes the flow valve 170, and opposing pressure in the port 171c of the flow valve 170 is vented to atmosphere by the exhaust port 189.

[0130]In some implementations, the actuator assemblies and the controller valves may be biased such as spring loaded. For instance, depressing the trigger 151 against a spring force may cause trigger valve 152 to shift from its initial or normal position and the flow valve 170 to move to an open or on position as provided herein. When the trigger 151 is released, the spring relaxes and may cause the trigger valve 152 to shift back to its initial or normal position, which may cause the flow valve 170 to move to the closed or off position as provided herein. In the case of the controller valve 180, a spool of the controller valve 180 may be shifted to its normal position as a biasing mechanism, e.g., spring, relaxes, such as during operation of the controller valve 180 in an unpressurized state, as provided herein. In other implementations, one or more actuators or valves of the pneumatic air excavator 100, e.g., of the actuator assembly and/or the controller, may be biased by a solenoid valve.

[0131]Various changes may be made in the form, construction and arrangement of the components of the present disclosure without departing from the disclosed subject matter or without sacrificing all of its material advantages. The form described is merely explanatory, and it is the intention of the following claims to encompass and include such changes. Moreover, while the present disclosure has been described with reference to various embodiments, it will be understood that these embodiments are illustrative and that the scope of the disclosure is not limited to them. Many variations, modifications, additions, and improvements are possible. Functionality may be separated or combined in blocks differently in various embodiments of the disclosure or described with different terminology. These and other variations, modifications, additions, and improvements may fall within the scope of the disclosure as defined in the claims that follow.