DUAL-FUNCTION PIN FOR PUSH-PULL AND LIFT-TURN STOPPERS

BACKGROUND

[0001]Drain closures offer selective opening and closing to prevent or allow fluid from entering a drain (e.g., of a bathtub, sink, laundry tub). While there are a variety of drain closures, U.S. Pat. No. 4,720,877 describes a drain closure that uses an interrupted metal ring fitted in a groove on a pin that is compressed in a bore of a stopper and expands to exert a force to hold the stopper in an open position. U.S. Pat. No. 6,418,570 describes another example of a drain closure.

[0002]It is with respect to this general technical environment that aspects of the present application are directed.

SUMMARY

[0003]In an aspect, the present application relates to a drain closure assembly, comprising: a strainer body comprising a bore with internal threads; a stopper comprising a head and a sleeve extending below the head of the stopper; and a pin comprising: a head, a shank extending below the head, threads disposed below the shank and configured to couple with the internal threads of the strainer body, an upper groove disposed in the outer surface of the shank and substantially adjacent to the head of the pin, a lower groove disposed in an outer surface of the shank, and a substantially flat shank surface disposed on the outer surface of the shank and extending along a length of the shank from below the upper groove past at least a lower wall forming the upper groove.

[0004]In some examples, the lower groove is configured to receive a friction ring.

[0005]In some examples, the friction ring is configured to frictionally contact an internal surface of the sleeve.

[0006]In some examples, the upper groove is configured to receive a D-ring, and wherein the D-ring is configured to sit on a shoulder of the stopper.

[0007]In some examples, the substantially flat shank surface extends from below the lower groove to a bottom surface of the head of the pin.

[0008]In some examples, the lower groove is disposed substantially halfway between the threads of the pin and the head of the pin.

[0009]In some examples, the head of the pin has a diameter that is greater than a diameter of the shank.

[0010]In some examples, the head of the pin comprises a drive configured to receive a tool.

[0011]In some examples, the lower groove is formed by an upper wall, a lower wall substantially parallel to the upper wall, and a back wall substantially orthogonal to the upper wall and the lower wall.

[0012]In some examples, the substantially flat shank surface extends from below the lower groove past the lower wall forming the upper groove.

[0013]In another aspect, the present application relates to a pin for a drain closure assembly, comprising: a head; a shank extending below the head; threads disposed below the shank and configured to couple with the internal threads of a strainer body; an upper groove disposed in the outer surface of the shank and substantially adjacent to the head of the pin; a lower groove disposed in an outer surface of the shank; and a substantially flat shank surface disposed on the outer surface of the shank and extending along a length of the shank from below the upper groove past at least a lower wall forming the upper groove.

[0014]In some examples, the lower groove is configured to receive a friction ring.

[0015]In some examples, the upper groove is configured to receive a D-ring.

[0016]In some examples, the substantially flat shank surface extends from below the lower groove to a bottom surface of the head of the pin.

[0017]In some examples, the lower groove is disposed substantially halfway between the threads of the pin and the head of the pin.

[0018]In some examples, the substantially flat shank surface extends from below the lower groove past the lower wall forming the upper groove.

[0019]In another aspect, the present application relates to a drain closure assembly, comprising: a strainer body comprising a bore with internal threads; a stopper comprising a head and a sleeve extending below the head of the stopper; a pin comprising: a head, a shank extending below the head, threads disposed below the shank and configured to couple with the internal threads of the strainer body, an upper groove disposed in the outer surface of the shank and substantially adjacent to the head of the pin, a lower groove disposed in an outer surface of the shank, and a substantially flat shank surface disposed on the outer surface of the shank and extending along a length of the shank from a bottom surface of the shank to a bottom surface of the head of the pin; and a D-ring configured to fit into the upper groove.

[0020]In some examples, the lower groove is formed by an upper wall, a lower wall substantially parallel to the upper wall, and a back wall substantially orthogonal to the upper wall and the lower wall.

[0021]In some examples, the head of the pin has a diameter that is greater than a diameter of the shank.

[0022]In some examples, the lower groove is configured to receive a friction ring, and wherein the upper groove is configured to receive a D-ring.

[0023]This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Additional aspects, features, and/or advantages of examples will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]There are shown in the drawings examples that are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and configurations shown.

[0025]FIG. 1 illustrates a perspective view of an example drain closure assembly in a lift-and-turn configuration in an open position.

[0026]FIG. 2 illustrates a front view of the example drain closure assembly from FIG. 1 in the lift-and-turn configuration in the closed position.

[0027]FIG. 3 illustrates a front view of the example drain closure assembly from FIG. 1 in the lift-and-turn configuration in an open position.

[0028]FIG. 4 illustrates a perspective view of an example pin and D-ring of the example drain closure assembly of FIGS. 1-3.

[0029]FIG. 5 illustrates a front view of the example pin and D-ring from FIG. 4.

[0030]FIG. 6 illustrates a side view of the example pin and D-ring from FIG. 4.

[0031]FIG. 7 illustrates a perspective view of an example drain closure assembly in a push-pull configuration in an open position.

[0032]FIG. 8 illustrates a front view of the example drain closure assembly from FIG. 7 in the push-pull configuration in a closed position.

[0033]FIG. 9 illustrates a front view of the example drain closure assembly from FIG. 7 in the push-pull configuration in an open position.

[0034]FIG. 10 illustrates a perspective view of an example pin and friction ring of the example drain closure assembly of FIGS. 7-9.

[0035]FIG. 11 illustrates a front view of the example pin and friction ring from FIG. 10.

[0036]FIG. 12 illustrates a side view of the example pin and friction ring from FIG. 10.

DETAILED DESCRIPTION

[0037]Referring concurrently to FIGS. 1-12, drain closure assembly 100 includes stopper assembly 65, strainer body 10, and pin 24. Stopper assembly 65 may include stopper 34, gasket 48, knob 54, and in some examples, D-ring 47. Strainer body 10 has a cylindrical wall 12 which includes external threads 14 to thread into a drain fitting under the floor of a wastewater receptacle such as a bathtub (or a sink, laundry tub or other drain opening). Within the strainer body 10, a drain passage 15 is provided for draining of liquid from the receptacle. The top edge of the strainer body 10 is provided with an annular flange 16. Formed within a lower portion of the strainer body 10 is a ring 18 carried on arms 20 secured to the inside surface of the wall 12. The ring 18 is concentric with the wall 12. Extending through the ring 18 is a bore 21 that has internal threads 22. Pin 24 (e.g., a post) is fixedly coupled to strainer body 10 at bore 21.

[0038]Generally, pin 24 is capable of at least two functions for facilitating the opening and closing of drain closure assembly 100. These two functions may be referred to herein as “lift-and-turn” (e.g., FIGS. 1-6) and “push-pull” (e.g., FIGS. 7-12). “Lift-and-turn” primarily takes advantage of D-ring 47 disposed in stopper assembly 65, and “push-pull” primarily takes advantage of friction ring 57 disposed in lower groove 32. Drain closure assembly 100 may support both functions separately, or even simultaneously (though in practice only one of D-ring 47 or friction ring 57 is necessary. For example, D-ring 47 may be disposed in stopper assembly 65 to cooperate with an upper groove 45 of the pin 24, and/or friction ring 57 may be disposed in lower groove 32 to take advantage of one or both functionalities. In either instance, the same pin 24 is able to be employed. This permits, among other things, the manufacturer of drain closure assembly 100 to eliminate the need for separate pins to be manufactured and simplifies the number of parts needed by plumbers or installers in the field.

[0039]In the illustrated examples, mounted within the strainer body 10 is pin 24 having male threads 26 on a bottom end of pin 24 that couple with the female threads 22 of ring 18. As will be appreciated, the male threads and female threads can be reversed on the bottom end of pin 24 and ring 18, respectively and achieve the same or similar result. The pin 24 can thus be threaded into ring 18 and is mounted in this manner to extend along a central axis C of the strainer body 10 and the pin 24. The pin 24 can be made of any rigid material, including plastics, metals, and/or ceramics.

[0040]The pin 24 includes a shank 27 and a head 28 that is enlarged in diameter compared to the shank 27. Shank 27 is disposed substantially adjacent to and above threads 26. The pin 24 has an open elongated vertical slot 30 that extends laterally through the pin 24 along axis C. Lower vertical slot 31, which has a diameter that is less than a diameter of vertical slot 30 and is disposed substantially adjacent to and below vertical slot 30, may extend laterally from a bottom portion of vertical slot 30 and out through the bottom of pin 24. Inner walls 33 of vertical slot 30 may narrow to inner walls 35 of lower vertical slot 31 by way of a chamfered surface 37 adjacent to inner walls 33 and inner walls 35 inside pin 24. In the depicted example, vertical slot 30 has a smaller diameter than shank 27.

[0041]Extending inwardly to form a recess in an outer surface 39 of shank 27 is lower groove 32. Lower groove 32 may be formed in an outer surface 39 of the shank 27 between threads 26 and head 28. For example, lower groove 32 may be disposed substantially halfway between threads 26 and head 28. Lower groove 32 may be indented in outer surface 39. In the illustrated example, lower groove includes an upper wall 86, back wall 87, and lower wall 88. In the illustrated example, the back wall 87 of lower groove 32 may be substantially parallel to axis C, and the lower wall 88 of lower groove 32 may be substantially parallel to upper wall 86 and substantially orthogonal to axis C (see, e.g., FIG. 6, which shows groove 57 without friction ring 57 installed). In other examples, the lower groove 32 may be formed in other shapes, such as by forming the upper, back, and lower walls as of lower groove 32 as one continuous curved surface, creating a substantially C-shaped cross section of lower groove 32. Other examples are possible and contemplated.

[0042]In the “push-pull” configuration (FIGS. 7-12), a friction ring 57, such as an O-ring or a metal ring, may be received by lower groove 32 to frictionally contact internal surface 43 to maintain stopper 34 at substantially any vertical position (e.g., along axis C) relative to pin 24, as will be described later. In examples, the friction ring 57 may be a discontinuous metal ring, the ends of which can be overlapped so that the friction ring 57 can be squeezed around shank 27 such that it sits in lower groove 32 and will not be dislodged from lower groove 32 when stopper 34 is moved along axis C. In other examples, the friction ring 57 may be a resilient rubber that can be stretched to slide over shank 27 and allowed to contract to sit into the lower groove 32. In examples, the friction ring 57 may be of a sufficient thickness, shape, and/or material to cause the friction ring to press outwardly against internal surface 43 of stopper 34 to frictionally resist movement of stopper 34 along axis C.

[0043]In examples, outer surface 39 may be generally cylindrical, but for a portion of outer surface 39 that is interrupted by flat shank surface 41 so as to create a substantially D-shaped cross section of shank 27. In examples, lower groove 32 is formed in the substantially cylindrical portion of outer surface 39 and terminates at both ends of lower groove 32 in the flat shank surface 41. Outer surface 39 may have a diameter D, which may be defined as a largest width of the shank 27 in a plane orthogonal to central axis C of pin 24. Flat shank surface 41 is disposed on outer surface 39 of shank 27. Flat shank surface 41 is a substantially flat surface that extends along a length of the shank 27 (e.g., from the bottom of shank 27, such as substantially adjacent to threads 26 or from a bottom surface 63 of shank 27, to a top of upper groove 45, which in the illustrated example is the bottom surface 59 of head 28). In examples, flat shank surface 41 may extend at least twenty-five percent of the length of pin 24. In other examples, flat shank surface 41 may extend at least about thirty percent, thirty-five percent, forty percent, forty-five percent, fifty percent, fifty-five percent, sixty percent, sixty-five percent, seventy percent, seventy-five percent, eighty percent, 85 percent, or 90 percent of the length of pin 24. Further, in examples, the diameter D of the shank 27 may be a constant for at least twenty-five percent of the length of pin 24. In other examples, the diameter D of the shank 27 may be a constant for at least thirty percent, thirty-five percent, forty percent, forty-five percent, fifty percent, fifty-five percent, sixty percent, sixty-five percent, seventy percent, seventy-five percent, eighty percent, 85 percent, or 90 percent of the length of pin 24. Flat shank surface 41 may be referred to as a cut face, sectioned face, machined face, cutout, or milled face, on shank 27. Flat shank surface 41 may be machined or otherwise formed by cutting into shank 27.

[0044]Also extending inwardly to form a recess in outer surface 39 of shank 27 is upper groove 45. Upper groove 45 may be indented compared to outer surface 39. Upper groove 45 may be disposed in an upper portion of shank 27, for example, substantially adjacent to head 28. For example, and as illustrated, bottom surface 59 of head 28 may form an upper wall of upper groove 45. In the illustrated example, the back wall 75 of upper groove 45 may be substantially parallel to axis C, and the lower wall (lower groove surface 55) of the upper groove 45 may be substantially parallel to bottom surface 59 of head 28 (see, e.g., FIGS. 6, 12). In other examples, the upper groove 45 may be formed in other shapes, such as by forming the upper, back, and lower walls as of upper groove 45 as one continuous curved surface, creating a substantially C-shaped cross section of upper groove 45. Other examples are possible and contemplated. In addition, upper groove 45 may be formed beneath head 28 (e.g., by creating an upper wall indented from outer surface 39 but separated from head 28.

[0045]In the “lift-and-turn” configuration (e.g., FIGS. 1-6), upper groove 45 may be configured to receive D-ring 47. D-ring 47 may be a substantially circular ring with an inside through hole that resembles the letter “D,” wherein the through hole is slightly larger than the cross section of shank 27 (FIGS. 4-6). For example, D-ring 47 may include flat inner ring surface 49 that is disposed inside D-ring 47 and on protruding D-ring portion 53. D-ring 47 may rest on shoulder 46 of stopper 34. Flat inner ring surface 49 may be configured to match with flat shank surface 41 so that D-ring 47 is able to slide up shank 27 during installation or when stopper assembly 65 is transitioning from a closed position to an open position. To “lock” or maintain stopper assembly 65 in an open position, stopper assembly 65 may be lifted from the closed position and then turned, such that flat inner ring surface 49 is turned within upper groove 45 to form an angle with flat shank surface 41 (such that flat inner ring surface 49 is no longer parallel with flat shank surface 41). As such, flat inner ring surface 49 is rotated within upper groove 45 such that there is an interference between protruding D-ring portion 53 and lower groove surface 55 of shank 27. In addition, gravitational pressure from the weight of the stopper assembly 65 may press the protruding D-ring portion 53 onto an edge of the lower groove surface of shank 27 and cause the flat inner ring surface 49 to be pressed against the bottom surface 59 of head 28. In this way, once stopper assembly 65 is rotated with D-ring 47 “locked” in upper groove 45, stopper assembly 65 is prevented from vertical movement (along axis C) with respect to pin 24, and stopper assembly 65 is maintained in a locked position, allowing fluid to flow into the drain. In examples, the flat shank surface 41 extends into and to the upper wall of the upper groove 45. That is, upper groove 45 is formed in the substantially cylindrical portion of outer surface 39 and terminates at both ends of upper groove 45 in flat shank surface 41. This “lift-and-turn” technique of opening and closing stopper assembly 65 may be used in addition to, or alternatively to, friction ring 57 (“push-pull”).

[0046]Pin 24 includes head 28 that includes a bottom head surface 59 prevents D-ring 47 from being slid past bottom head surface 59. Head 28 may have a diameter that is larger than the diameter of shank 27. Head 28 may include drive 61 which may be shaped or configured to receive a tool, such as a screwdriver. For example, drive 61 may be a hexagonal shape, although other shapes are possible and contemplated.

[0047]Fitted on pin 24 is stopper 34 having a disk-shaped head 36 and a sleeve 38 projecting downwards from head 36. The head 36 has an enlarged flange 40 forming its top surface. A bore 42 is formed centrally through the stopper 34. The bore is surrounded by an internal surface 43 of the stopper 34. The upper portion of the bore 42, within head 36 and surrounded by threaded portion 44, has a greater diameter than the remainder of the bore 42 than shank 27. The lower portion of bore 42 has a slightly greater diameter than shank 27 as described previously. Upwardly facing shoulder 46 is formed within the bore 42 at the lower end of the threaded portion 44. The stopper head 36 (e.g., flange 40) is larger in diameter than the diameter of the drain passage 15 provided within the strainer body 10. Stopper 34 is able to slide up and down (substantially parallel to axis C) relative to pin 24 (e.g., pin 24 may be stationary or fixed to strainer body 10 at bore 21).

[0048]A gasket 48 includes a ring portion 50, which fits closely on the outer edge of the stopper head 36 in a recess 52 of stopper 34 at a location immediately below the flange 40. The gasket 48 also includes a rim portion 51 which projects generally radially outwardly from the ring portion 50. As such, the rim 51 may have a frusto-conical shape. When the stopper 34 is in a closed position, the rim 51 is pressed flat against the strainer body flange 16 by the stopper flange 40 to form a tight seal which closes the drain passage 15 of the strainer body. In any open position the stopper head 36 and gasket 48 are displaced above the top of the strainer body 10, and the drain is then opened for drainage of fluid from the bathtub or other vessel equipped with drain closure assembly 100. It should be understood that the gasket 48 is optional and is not necessary for a satisfactory seal. The stopper 34 may instead, for example, be equipped with an O-ring or another type of sealing element, or it may be constructed to seal the drain passage without a separate sealing element.

[0049]Knob 54 is threadingly coupled to head 36 of stopper 34. Specifically, external threads 58 of knob 54 couple to internal threads 44 of stopper 34. Knob 54 may include knurled exterior surface 56 to facilitate lifting and/or twisting. When D-ring 47 is installed, D-ring 47 may be disposed in between knob 54 and shoulder 46 of stopper 34 (FIG. 1). When D-ring 47 is not installed, there may be a space (e.g., approximately equal to the width of D-ring 47) in between knob 54 and shoulder 46 of stopper 34 (FIG. 8). Extending upwardly into knob 54 is internal blind passage 60 having a larger diameter than a diameter of pin head 28.

[0050]In assembling or during installation of the drain closure assembly 100, strainer body 10 is placed within a drain. Gasket 48 may be placed in recess 52 of stopper 34. In the “lift-and-turn” configuration (e.g., FIGS. 1-6), D-ring 47 is placed on shoulder 46 of stopper 34. In the “push-pull” configuration (e.g., FIGS. 7-12), friction ring 57 is placed in lower groove 32 of stopper 34. The top portion of stopper 34 is applied to the bottom end of pin 24, and the head 28 of the pin 24 is able to enter bore 42 in the area surrounded by threads 44, but may be unable to enter the smaller main portion of bore 42 as the diameter of head 28 may be greater than the diameter of vertical slot 30. Threads 26 of pin 24 are aligned with threads 22 of ring 18, and a tool is applied to drive 61 of pin 24 to screw in pin 24 into threads 22 of ring 18. Finally, external threads 58 of knob 54 are screwed into internal threads 44 of stopper 34.

[0051]In the “lift-and-turn” configuration (FIGS. 1-6), and in the open position (FIGS. 1 and 3), the head 28 contacts or sits on D-ring 47, which sits on shoulder 46. In the “push-pull” configuration (FIGS. 7-12) and in the open position (FIGS. 7 and 9), at least a portion of head 28 may sit below shoulder 46. The upper end of bore 42 is closed by knob 54. In both “lift-and-turn” and “push-pull” configurations and in the closed position (FIGS. 2 and 8), head 28 of pin 24 is disposed in passage 60 within knob 54 and is spaced from shoulder 46. Further, the head 28 of pin 24 is and spaced from D-ring 47 in the “lift-and-turn” closed configuration-that is, D-ring 47 remains sitting on shoulder 46, and D-ring 47 moves with stopper assembly 65).

[0052]In use, when friction ring 57 is disposed in recess 32 (“push-pull”, FIGS. 7-12), stopper 34 can be moved to the closed position from the open position by pressing downwardly with, e.g., a hand or foot on the stopper or knob 54. The stopper 34 then slides downwardly until the gasket 48 is flattened and seals tightly against the flange 16 of the strainer body 10. The force provided by the friction ring 57 received in recess 32, as described above, helps to retain the stopper in the closed position, thereby enhancing its effectiveness in preventing leakage.

[0053]Additionally or alternatively, in use, when D-ring 47 is disposed in stopper 34 (“lift-and-turn”, FIGS. 1-6), to move stopper 34 to the closed position from the open position, stopper assembly 65 rotates such that the flat inner ring surface 49 of D-ring 47 is in alignment (substantially parallel with) flat shank surface 41. Stopper assembly 65 may then be moved to the closed position by pressing downwardly or releasing grip on stopper assembly 65. Stopper assembly 65 may slide downwardly until gasket 48 is flattened and seals tightly against the flange 16 of the strainer body 10. When friction ring 57 is also in use, stopper assembly 65 may be pushed down such that stopper 34 slides downwardly until the gasket 48 is flattened and seals tightly against the flange 16 of the strainer body 10.

[0054]When friction ring 57 is disposed in recess 32 (“push-pull”, e.g., FIGS. 7-12), to open the drain closure assembly 100 to any position, knob 54 may be grasped and lifted upwardly to raise the stopper 34 to any open position. When the stopper 34 has been raised to an open position, it can be released and the force provided by the ring/O-ring in recess 32 expanding or pressing against the surface 43 retains the stopper 34 in an open position. For example, the friction ring 57 may be made of a resilient material, such as metal or rubber, that exerts outward pressure against surface 43. The shape and depth of the lower groove 32 and size, material, and shape of friction ring 57 may be configured to cause friction ring 57 to be held in place and resist moving out of groove 32 when the stopper assembly 65 is moved between the open and closed positions.

[0055]Additionally or alternatively, when D-ring 47 is installed (“lift-and-turn”, FIGS. 1-6), to move stopper 34 to the open position from the closed position, stopper assembly 65 may be lifted until D-ring 47 comes into contact with bottom surface 59 of head 28. During this lifting process, flat inner ring surface 49 is in alignment or parallel with flat shank surface 41. Stopper assembly 65 may then be rotated such that flat inner ring surface 49 of D-ring 47 is no longer in alignment (parallel with) flat shank surface 41. In particular, D-ring 47 rotates within upper groove 45. Stopper assembly 65 may then be released and stopper assembly 65 may be “locked” in the open position and is able to maintain this open position due to the interference between D-ring 47 and upper groove 45.

[0056]The friction ring 57 in recess 32 may be configured to expand or press outwardly with sufficient force to provide a frictional force between friction ring 57 and stopper 34 that is greater than the gravitational force applied by the combined stopper 34, knob 54, and gasket 48. Accordingly, the weight of the combined stopper 34, knob 54, and gasket 48 is insufficient to lower the stopper 34 from any open position, and it is maintained in an open position until again moved to the closed position (or an adjusted open position). In some examples, the stopper assembly 65 may rotate with respect to pin 24. However, when D-ring 47 is installed, the stopper assembly 65 may only be able to rotate when D-ring 47 is received in upper groove 45.

[0057]Although specific devices or components have been recited throughout the disclosure as performing specific functions, one of skill in the art will appreciate that these devices or components are provided for illustrative purposes, and other devices or components may be employed to perform the functionality disclosed herein without departing from the scope of the disclosure. For example, unless otherwise specified, any threaded connection between components disclosed herein may be replaced by other forms of attachment, such as bonding, welding, etc.

[0058]This disclosure describes some embodiments of the present technology with reference to the accompanying drawings, in which only some of the possible embodiments were shown. Other aspects may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments were provided so that this disclosure was thorough and complete and fully conveyed the scope of the possible embodiments to those skilled in the art. Further, as used herein and in the claims, the phrase “at least one of element A, element B, or element C” is intended to convey any of: element A, element B, element C, elements A and B, elements A and C, elements B and C, and elements A, B, and C. Further, one having skill in the art will understand the degree to which terms such as “about” or “substantially” convey in light of the measurement techniques utilized herein. To the extent such terms may not be clearly defined or understood by one having skill in the art, the terms “about” or “substantially” shall mean plus or minus ten percent. Relative positioning terms like “top” “bottom” “side” “up” “down” or other such terms may be used with respect to the directions when viewing each drawing and/or may be used with respect to proximity to the ground. For example, “bottom” is more proximal to the ground than “top.” “Up” and “down” or “vertical” refer to directions along central axis C, where “up” refers to higher on the drawing sheet or further from the ground, and “down” refers to lower on the drawing sheet or lower to the ground. Unless stated otherwise, the depicted Figures may depict components oriented with the bottom of the Figure oriented towards the ground.

[0059]Although specific embodiments are described herein, the scope of the technology is not limited to those specific embodiments. Moreover, while different examples and embodiments may be described separately, such embodiments and examples may be combined with one another in implementing the technology described herein. One skilled in the art will recognize other embodiments or improvements that are within the scope and spirit of the present technology. Therefore, the specific structure, acts, or media are disclosed only as illustrative embodiments. The scope of the technology is defined by the following claims and any equivalents therein.