Construction machine

RELATED APPLICATIONS

[0001]The present application claims priority from German Patent Application Ser. No. DE 10 2024 128 310.6 filed Sep. 30, 2025, which is incorporated herein by reference.

BACKGROUND OF THE DISCLOSURE

Field of the Disclosure

[0002]The disclosure relates to a construction machine including a machine frame, a milling drum arranged on the machine frame, at least three wheels or tracks, at least three lifting columns supporting the machine frame from the wheels or tracks, and an advance drive for driving at least one of the wheels or tracks.

Description of the Prior Art

[0003]Self-propelled construction machines, in particular road milling machines, stabilizers, recyclers or surface miners, frequently comprise at least one machine frame, at least one milling drum arranged on the machine frame for milling a ground pavement, and at least three travelling devices, which are connected to the machine frame via lifting columns. Furthermore, a driving device is provided in most cases for driving the at least three travelling devices. The lifting columns are frequently designed for the purpose of raising or lowering the machine frame relative to the travelling devices.

[0004]During ordinary operation of a construction machine comprising a milling drum, it is desirable that the operator is in a position to maintain control of the forward or backward movement of the machine independent of the operation of the milling drum. However, if the reaction forces exerted on the milling drum by the ground surface exceed the forces acting on the milling drum through the weight, the driving force and the braking force of the construction machine, it may come to a sudden and undesirable lifting of the construction machine. In particular, when the travelling devices and the working device are rotating in the same axis, it may come to an undesirable lifting and a sudden forward or backward jolt of the construction machine.

[0005]When the machine is lowered into the cut too quickly, it may also happen that the reaction force acting on the rotating milling drum causes the construction machine to suddenly move forward or backward depending on the cutting mode, that is, in downward or upward cutting mode.

[0006]With systems in accordance with the state of the art, such undesirable events were usually treated in that the event was registered after having occurred, and then the operating systems of the machine were switched off. Examples of this are found in U.S. Pat. Nos. 4,929,121, 5,318,378 and 5,879,056.

SUMMARY OF THE DISCLOSURE

[0007]It is the object of the present disclosure to provide a construction machine, and a method for controlling the same, in order to reduce or entirely prevent the occurrence of undesirable forward or backward jolts.

[0008]The above mentioned object is achieved by the features of the claims.

[0009]The disclosure advantageously provides that at least two sensors per travelling device are arranged on the respective lifting columns, wherein the sensors are designed to each detect one parameter, which corresponds to the load acting on the travelling device.

[0010]The construction machine may comprise a controller, which detects the deviation between the two each sensors provided for each travelling device. The deviation concerns the deviation between the values of the parameters detected by the sensors.

[0011]The construction machine may be designed in such a manner that, when a first predetermined deviation limit value for the deviation between the two sensors provided for one travelling device is exceeded, a message is given to the operator of the machine.

[0012]The construction machine may be designed in such a manner that, when a second deviation limit value for the deviation between the two sensors provided for one travelling device is exceeded that is higher than the first deviation limit value, the controller emits at least one signal in order to stop the milling drum and/or the forward movement of the construction machine.

[0013]The construction machine may be designed in such a manner that, after the first deviation limit value has been exceeded, the travel drive may continue to be operated or may be reactivated. Said first deviation limit value is also the first deviation limit value for the deviation between the two sensors provided for one travelling device.

[0014]The construction machine may be designed in such a manner that, after the second deviation limit value has been exceeded, the travel drive may only be reactivated when the deviation between the two sensors provided for one travelling device has fallen below the second deviation limit value again. Said second deviation limit value is also the second deviation limit value for the deviation between the two sensors provided for one travelling device.

[0015]The construction machine may comprise a controller that is designed to determine a mean value of the loads acting on two travelling devices, wherein the parameters detected by the sensors assigned to the two travelling devices are used for the purpose of calculating said mean value. Two sensors and therefore two parameters are provided for each travelling device. To calculate the mean value of the loads acting on the two travelling devices, either one of the measured values, preferably the lowest measured value of the two sensors, or the mean value of the two sensors may be used for each travelling device.

[0016]The construction machine may be designed in such a manner that the two travelling devices for which the mean value of the load acting on the same is determined are two front and/or two rear travelling devices.

[0017]The construction machine may be designed in such a manner that the two travelling devices for which the mean value of the load acting on the same is determined are one front and one rear travelling device.

[0018]In a construction machine comprising four lifting columns, for example, a mean value may be determined of the load acting on the two front or the two rear travelling devices. In this design, the parameters detected by the sensors assigned to the respective travelling devices are used for the purpose of calculating the mean value. Alternatively or additionally, it would be possible to calculate the mean value of the load acting on the two right or on the two left travelling devices. In a construction machine comprising three travelling devices, for example, the mean value may be determined of the load acting on the single front and one rear travelling devices.

[0019]The construction machine may be designed in such a manner that, in the case of multiple mean values being determined, the smallest value of the mean values is compared with at least one predetermined mean load limit value. Said mean load limit value for the mean value has to be differentiated from the aforementioned deviation limit value for the deviation between the two sensors provided for one travelling device.

[0020]The construction machine may be designed in such a manner that, when the smallest value of the mean values falls below a first predetermined mean load limit value for the mean value, the controller emits a signal in order to reduce the advance movement of the construction machine.

[0021]The construction machine may be designed in such a manner that, when the smallest value of the mean values falls below a second predetermined mean load limit value for the mean value, the controller emits a signal in order to stop the working device and/or the advance movement of the construction machine.

[0022]The construction machine may be designed in such a manner that, when the smallest value of the mean load limit values falls below a second predetermined mean load limit value, the controller emits a signal in order to stop the working device and/or the advance movement of the construction machine.

[0023]A method may furthermore be provided for controlling a self-propelled construction machine, in particular road milling machine, stabilizer, recycler or surface miner, comprising at least one machine frame, at least one working device, in particular milling drum, arranged on the machine frame for working a ground pavement, at least three travelling devices, which are connected to the machine frame via lifting columns, wherein the machine frame is raised and lowered relative to the travelling devices by means of lifting columns, at least one driving device for driving the at least three travelling devices, wherein at least two sensors per travelling device are provided on the respective lifting columns, wherein the sensors each detect one parameter, which corresponds to the load acting on the travelling device.

[0024]The deviation between the two each sensors provided for each travelling device may be detected by means of a controller.

[0025]The deviation detected may be compared with at least one predetermined deviation limit value. Said deviation limit value is the limit value for the deviation between the two sensors provided for one travelling device.

[0026]When a first predetermined deviation limit value for the deviation between the two sensors provided for one travelling device is exceeded, a message may be given to the operator of the machine.

[0027]When a second deviation limit value for the deviation between the two sensors provided for one travelling device is exceeded that is higher than the first deviation limit value, at least one signal may be emitted by the controller in order to stop the milling drum and/or the forward movement of the construction machine.

[0028]After the first deviation limit value has been exceeded, the travel drive may continue to be operated or may be reactivated.

[0029]After the second deviation limit value has been exceeded, the travel drive may only be reactivated when the deviation between the two sensors provided for one travelling device has fallen below the second deviation limit value again.

[0030]The controller may furthermore determine a mean value of the loads acting on two travelling devices, wherein the parameters detected by the sensors assigned to the two travelling devices are used for the purpose of calculating said mean value. Two sensors and therefore two parameters are provided for each travelling device. To calculate the mean value of the loads acting on the two travelling devices, either one of the measured values, preferably the lowest measured value of the two sensors, or the mean value of the two sensors may be used for each travelling device.

[0031]The two travelling devices for which the mean value of the load acting on the same is determined may be two front and/or two rear travelling devices.

[0032]The two travelling devices for which the mean value of the load acting on the same is determined may be one front and one rear travelling device.

[0033]In the case of multiple mean values being determined, the smallest value of the mean values may be compared with at least one predetermined mean load limit value. Said mean load limit value for the mean value has to be differentiated from the aforementioned deviation limit value for the deviation between the two sensors provided for one travelling device.

[0034]When the smallest value of the mean values falls below a first predetermined mean load limit value, the controller may emit a signal in order to reduce the advance movement of the construction machine.

[0035]When the smallest value of the mean values falls below a second predetermined mean load limit value, the controller may emit a signal in order to stop the working device and/or the advance movement of the construction machine.

BRIEF DESCRIPTION OF THE DRAWINGS

[0036]Hereinafter, embodiments of the disclosure are illustrated in more detail with reference to the drawings.

[0037]The following is shown schematically:

[0038]FIG. 1: shows a schematically depicted self-propelled construction machine (1),

[0039]FIG. 2: shows a section of a schematically depicted lifting column (10) with two sensors (12) arranged on the same,

[0040]FIG. 3: shows a schematic depiction of a top view of the construction machine with lifting columns,

[0041]FIG. 4: shows a schematic depiction of a self-propelled construction machine with a working device (4).

DETAILED DESCRIPTION

[0042]FIG. 1 shows a schematic depiction of a self-propelled construction machine 1, which may in particular be designed as a road milling machine, stabilizer, recycler or surface miner. The construction machine 1 comprises a machine frame 2, which may serve as a supporting structure and may carry the various components of the machine.

[0043]A working device 4 is arranged on the machine frame 2 which, in the present case, is designed as a milling drum. The milling drum 4 is designed for the purpose of working a ground pavement or ground surface 6 in that it rotates and removes the material of the ground pavement with tools arranged on the milling drum. The rotating movement of the milling drum 4 is indicated in FIG. 4 by an arrow.

[0044]The construction machine 1 is furthermore equipped with at least three travelling devices 10, which are connected to the machine frame 2 via lifting columns 14. The schematic construction machine 1 depicted in FIG. 1 comprises four travelling devices 10. The lifting columns 14 are designed for the purpose of raising or lowering the machine frame 2 relative to the travelling devices 10. The respective load acting on the respective travelling device 10 is indicated in FIG. 1 by the number 15. The travelling devices 10 may be wheels or tracks and may be referred to as wheels or tracks 10.

[0045]At least two sensors 12 (FIG. 2) per travelling device 10 are arranged on the lifting columns 14. Said sensors are designed to each detect one parameter, which corresponds to the load 15 acting on the travelling device. The parameters detected are transmitted to a controller 16, which processes the data and sends appropriate control commands to the construction machine 1.

[0046]The controller 16 is capable of detecting the deviation between the two each sensors provided for each travelling device, and may compare said deviation with at least one predetermined deviation limit value. When a first predetermined deviation limit value is exceeded, a message may be given to the operator of the machine. When a second deviation limit value is exceeded that is higher than the first limit value, the controller 16 may emit at least one signal in order to stop the milling drum 4 and/or the forward movement of the construction machine 1.

[0047]In addition, the controller 16 may determine a mean value of the load 15 acting on two travelling devices, wherein the parameters detected by the sensors assigned to the two travelling devices 10 are used for the purpose of calculating said mean value. Two sensors 12 and therefore two parameters are provided for each travelling device 10. To calculate the mean value of the loads 15 acting on the two travelling devices 10, either one of the measured values, preferably the lowest measured value of the two sensors 12, or the mean value of the two sensors 12 may be used for each travelling device 10.

[0048]The two travelling devices 10 for which the mean value of the load acting on the same is determined may be two front and/or two rear travelling devices. In the case of multiple mean values being determined, the smallest value of the mean values may be compared with at least one predetermined mean load limit value. When the smallest value of the mean values falls below a first predetermined mean load limit value, the controller 16 emits a signal in order to reduce the advance movement of the construction machine 1. When the smallest value of the mean values falls below a second predetermined mean load limit value, the controller 16 emits a signal in order to stop the working device 4 and/or the advance movement of the construction machine 1.

[0049]FIG. 1 therefore illustrates the components and their interaction in the self-propelled construction machine 1, wherein the sensors 12 and the controller 16 play a central role in monitoring and controlling the operations of the machine.

[0050]FIG. 1 shows a schematic depiction of a lifting column 10 of a self-propelled construction machine, in particular a road milling machine, a stabilizer, a recycler or a surface miner. The lifting column 10 is connected to a machine frame 2. Two sensors 12 are attached to the lifting column 10, which each detect one parameter that corresponds to the load 14 acting on the lifting column 10.

[0051]The machine frame 2 is the central structural component of the construction machine, to which various components are attached. The lifting column 14 serves the purpose of raising or lowering the machine frame 2 relative to the travelling devices 10. This makes it possible to adjust the working height of the construction machine.

[0052]The sensors 12 are mounted on the upper side of the lifting column 14 and are designed to measure the load acting on the respective travelling device. Said sensors continuously provide data to a controller, which processes the detected parameters. The precise positioning of the sensors 12 on the lifting column 14 ensures a precise detection of the load distribution and allows precise control of the operations of the machine.

[0053]The controller, which is depicted in FIG. 1, receives the data from the sensors 12 and analyses the deviations between the measured loads. Said deviations may be compared with predetermined deviation limit values in order to ensure that the construction machine is working within safe and efficient operating conditions. When a first predetermined deviation limit value is exceeded, a message may be given to the operator of the machine. When a second, higher limit value is exceeded, the controller 16 may emit a signal in order to stop the milling drum and/or the forward movement of the construction machine.

[0054]FIG. 2 shows a lifting column 14 with two sensors 12 attached to the same, which work in connection with the machine frame 2 in order to monitor and control the load distribution to the travelling devices. The precise detection and analysis of the load parameters by the sensors 12 and the controller ensures safe and efficient operation of the self-propelled construction machine.

[0055]FIG. 3 shows a schematic depiction of a self-propelled construction machine 1, in particular a road milling machine, a stabilizer, a recycler or a surface miner. The construction machine comprises a machine frame 2, which serves as a central structure and to which various components are attached.

[0056]Four travelling devices 10 are arranged on the machine frame 2, which are connected to the machine frame 2 via lifting columns 14. Said lifting columns 14 are designed to raise or lower the machine frame 2 relative to the travelling devices 10 in order to allow the adjustment to different working conditions.

[0057]At least two sensors 12 are assigned to each travelling device 10, which are attached at the respective lifting columns 14. Said sensors are designed for the purpose of detecting parameters that correspond to the load L_VL, L_VR, L_HL, L_HR acting on the travelling device 10. The load sensors have been labelled in FIG. 3 as als L_VL (load front left), L_VR (load front right), L_HL (load rear left) und L_HR (load rear right).

[0058]The detected load parameters are transmitted to a controller 16 (not depicted in FIG. 3), which detects the deviations between the two each sensors provided for each travelling device 10. Said controller 16 compares the detected deviations with at least one predetermined deviation limit value. When a first predetermined deviation limit value is exceeded, a message is given to the operator of the machine. When a second, higher limit value is exceeded, the controller 16 emits a signal in order to stop the milling drum 4 and/or the forward movement of the construction machine 1.

[0059]In addition, the controller is designed for the purpose of determining a mean value of the load 15 acting on two travelling devices 10. The parameters detected by the sensors 12 assigned to the two travelling devices 10 are used for the purpose of calculating the mean value. The two travelling devices 10 for which the mean value of the load 15 acting on the same is determined may be two front and/or two rear travelling devices. Alternatively, the mean value may also be determined for one front left and one rear left or one front right travelling device.

[0060]In the case of multiple mean values being determined, the smallest value of the mean values is compared with at least one predetermined mean load limit value. When the smallest mean value falls below a first predetermined mean load limit value, the controller emits a signal in order to reduce the advance movement of the construction machine 1. When the smallest mean value falls below a second, lower mean load limit value, the controller emits a signal in order to stop the working device 4 and/or the advance movement of the construction machine 1.

[0061]FIG. 3 illustrates the arrangement of the sensors and their positioning on the travelling devices 10, as well as the distribution of the lifting columns L_VL, L_VR, L_HL, L_HR, which are of central importance for controlling and monitoring the construction machine 1.

[0062]FIG. 4 shows a schematic depiction of a self-propelled construction machine 1, which may in particular be used as a road milling machine, stabilizer, recycler or surface miner. The construction machine 1 comprises a machine frame 2 to which a working device 4, in particular a milling drum, is attached. Said working device 4 serves the purpose of working a ground pavement 6.

[0063]The working device 4 is arranged in such a manner that it enters into contact with the ground pavement 6 and works the same. The milling drum 4 is mounted to rotate and features a rotating movement 16, as indicated by the arrow in the FIG. Said rotating movement allows milling or crushing of the ground pavement 6.

[0064]A driving device in the form of an advance drive 10.1 is provided in order to drive the travelling devices and therefore allow the movement of the construction machine 1. The advance drive 10.1 may for example be a hydraulic drive motor associated with the wheel or track 10. The driving operation is effected in the direction of arrow F, as indicated in FIG. 4.

[0065]A feature of the construction machine 1 is the arrangement of at least two sensors 12 per travelling device on the respective lifting columns. Said sensors 12 are designed to each detect one parameter, which corresponds to the load 15 acting on the travelling device. The detected parameters are forwarded to a controller 16, which detects the deviation between the two each sensors 12 provided for each travelling device.

[0066]The controller 16 compares the detected deviation with at least one predetermined deviation limit value. When a first predetermined deviation limit value is exceeded, a message is given to the operator of the machine. When a second deviation limit value is exceeded that is higher than the first deviation limit value, the controller emits at least one signal in order to stop the milling drum 4 and/or the forward movement of the construction machine 1.

[0067]In addition, the controller is designed to determine a mean value of the load 15 acting on two travelling devices 10. The parameters detected by the sensors 12 assigned to the two travelling devices 10 are used for the purpose of calculating the mean value. The two travelling devices 10 for which the mean value of the load 15 acting on the same is determined may be two front and/or two rear travelling devices.

[0068]If multiple mean values are determined, the smallest value of the mean values is compared with at least one predetermined mean load limit value. When the smallest value of the mean values falls below a first predetermined mean load limit value, the controller 16 emits a signal in order to reduce the advance movement of the construction machine 1. When the smallest value of the mean values falls below a second predetermined mean load limit value, the controller emits a signal in order to stop the working device 4 and/or the advance movement of the construction machine 1.