AMPHIBIOUS WORK VEHICLE

Abstract

Amphibious undercarriage systems, drive systems and work vehicles are disclosed herein. In an embodiment, an amphibious undercarriage system includes a pontoon, a first shaft, a second shaft, a track chain and at least one motor. The pontoon has a first end and a second end and is configured to float atop a liquid body. The first shaft is disposed at the first end of the pontoon. The second shaft is disposed at the second end of the pontoon. The track chain is movably attached to the pontoon so as to travel around the pontoon and moveably engaged with the first shaft and the second shaft. The motor is configured to drive the first shaft to cause the track chain to travel around the pontoon and the second shaft to rotate due to engagement with the track chain.

Claims

1. An amphibious undercarriage system for a work vehicle, the amphibious undercarriage system comprising: a pontoon having a first end and a second end and being configured to float atop a liquid body; a first shaft disposed at the first end of the pontoon; a second shaft disposed at the second end of the pontoon; a track chain movably attached to the pontoon so as to travel around the pontoon and moveably engaged with the first shaft and the second shaft; and at least one motor configured to drive the first shaft to cause the track chain to travel around the pontoon and the second shaft to rotate due to engagement with the track chain.

2. The amphibious undercarriage system of claim 1, wherein the at least one motor includes a first hydraulic motor and a second hydraulic motor, the first hydraulic motor is attached to a first side of the first shaft, and the second hydraulic motor is attached to an opposite second side of the first shaft.

3. The amphibious undercarriage system of claim 2, comprising first and second bearings connecting the second shaft to the pontoon.

4. The amphibious undercarriage system of claim 2, wherein a first hydraulic oil line is connected to the first hydraulic motor, and a second hydraulic oil line is connected to the second hydraulic motor.

5. The amphibious undercarriage system of claim 1, wherein the pontoon includes a first pontoon and a second pontoon, and the track chain includes a first track chain movably attached to the first pontoon so as to travel around the first pontoon and a second track chain movably attached to the second pontoon so as to travel around the second pontoon in a same direction as the first track chain.

6. The amphibious undercarriage system of claim 5, comprising a frame including a support body and a support member, the support member includes a first end and a second end, the first pontoon includes a first cavity that receives the first end of the support member, and the second pontoon includes a second cavity that receives the second end of the support member.

7. The amphibious undercarriage system of claim 1, wherein the first end of the pontoon is a rear end of the pontoon.

8. An amphibious work vehicle, the amphibious work vehicle comprising: an amphibious undercarriage system including at least one pontoon configured to float atop a liquid body and at least one track chain movably attached to the pontoon so as to travel around the pontoon in a length direction; a vehicle body pivotally attached to the amphibious undercarriage system and including an operating room for a human operator; and a work implement system pivotally attached to the cab and being controlled by the human operator in the operating room to perform excavation work.

9. The amphibious work vehicle of claim 8, wherein the at least one pontoon includes a first pontoon and a second pontoon positioned on opposite sides of the vehicle body, and the at least one track chain includes a first track chain movably attached to the first pontoon so as to travel around the first pontoon in the length direction and a second track chain movably attached to the second pontoon so as to travel around the second pontoon in the length direction.

10. The amphibious work vehicle of claim 9, wherein the amphibious undercarriage system includes a frame, the first pontoon and the second pontoon are moveably attached to opposite sides of the frame, the first pontoon and the second pontoon are configured to move towards each other into a retracted configuration and away from each other in an extended configuration.

11. The amphibious work vehicle of claim 9, wherein the amphibious undercarriage system includes a frame, the first pontoon and the second pontoon are attached to opposite sides of the frame, and the vehicle body is pivotally attached to the frame.

12. The amphibious work vehicle of claim 8, wherein the work implement system includes a boom extension, an arm extension and an excavator bucket, the boom extension is pivotally attached to the vehicle body, the arm extension is pivotally attached to the boom extension, and the excavator bucket pivotally attached to the arm extension.

13. The amphibious work vehicle of claim 8, wherein the amphibious undercarriage system includes a pontoon, a first shaft, a first hydraulic motor, a second hydraulic motor, a second shaft, a first hydraulic oil line and a second hydraulic oil line, the first shaft attached at a first end of the pontoon, the first shaft having a first end and a second end; the first hydraulic motor is attached to the first end of the first shaft, the second hydraulic motor attached to the second end of the first shaft, the second shaft is not attached to a hydraulic motor, the first hydraulic oil line connected to the first hydraulic motor, and the second hydraulic oil line is connected to the second hydraulic motor.

14. A drive system for an amphibious undercarriage system for a work vehicle, the drive system comprising: a frame configured to attach to a pontoon; a first shaft configured to attach to a first end of the pontoon; a second shaft configured to attach to a second end of the pontoon; a first hydraulic motor attached to a first side of the first shaft; a second hydraulic motor attached to a second side of the first shaft; a first hydraulic oil line extending from the frame to the first hydraulic motor, and a second hydraulic oil line extending from the frame to the second hydraulic motor, the first shaft and the second shaft having parallel rotational axes, the second shaft is configured to be driven by rotation of the first shaft due to engagement with a track chain driven by the first shaft.

15. The drive system of claim 14, wherein the first shaft includes a plurality of first sprockets configured to engage and drive movement of the track chain, and the second shaft includes a plurality of second sprockets configured to engage and be driven by movement of the track chain.

16. The drive system of claim 14, comprising the frame includes a support body and a support member extending laterally from the support body, and the support member attaches the frame to the pontoon.

17. The drive system of claim 16, wherein the support member includes a first support member and a second support member, and each of the first support member and the second support member are configured to extend into respective cavities in the pontoon

18. The drive system of claim 14, comprising a third shaft configured to attach to a first end of a second pontoon, a fourth shaft configured to attach to a second end of the second pontoon, a third hydraulic motor attached to a first side of the third shaft, a fourth hydraulic motor attached to a second side of the third shaft, a third hydraulic oil line extending from the frame to the third hydraulic motor, and a fourth hydraulic oil line extending from the frame to the fourth hydraulic motor

19. The drive system of claim 18, wherein the third shaft and the fourth shaft have parallel rotational axes, the fourth shaft configured to be driven by rotation of the third shaft due to engagement with a second track chain driven by the third shaft.

20. The drive system of claim 14, wherein the second shaft is not attached to a hydraulic motor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Referring now to the attached drawings which form a part of this original disclosure:

[0013] FIG. 1 illustrates a perspective view of an example embodiment of an amphibious work vehicle in accordance with the present disclosure;

[0014] FIG. 2 illustrates a side elevational view of the amphibious work vehicle of FIG. 1 with the work implement system in different configurations;

[0015] FIG. 3 illustrates a perspective view of an example embodiment of the amphibious undercarriage system of the amphibious work vehicle of FIG. 1;

[0016] FIG. 4 illustrates a partial side elevational view of an example embodiment of the amphibious undercarriage system of FIG. 3;

[0017] FIG. 5 illustrates an exploded assembly view of an example embodiment of the drive system of the amphibious undercarriage of FIG. 3;

[0018] FIG. 6 illustrates a perspective view of an example embodiment of the hydraulic motors and the bearings of the drive system of FIG. 5; and

[0019] FIG. 7 illustrates an example embodiment of the hydraulic circuit of the drive system of the amphibious undercarriage of FIG. 3; and

[0020] FIG. 8 illustrates front elevational views showing the amphibious work vehicle of FIG. 1 in both a retracted configuration and an extended configuration.

DETAILED DESCRIPTION

[0021] Selected exemplary embodiments will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the exemplary embodiments are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0022] FIGS. 1 and 2 illustrate an example embodiment of an amphibious work vehicle 10 in accordance with the present disclosure. In the illustrated embodiment, the amphibious work vehicle 10 includes a vehicle body 12 and an amphibious undercarriage system 14. The vehicle body 12 is rotatably connected to the amphibious undercarriage system 14. More specifically, as seen in FIG. 3, the vehicle body 12 is configured to rotate about an axis A in the center of the amphibious undercarriage 14 by a revolving device. The vehicle body 12 also includes a cab 16 and a work implement system 18. The cab 16 provides an operating room and a control system from which a human operator operates the amphibious work vehicle 10. The work implement system 18 extends outward from the vehicle body 12 and is controlled by the operator in the cab 16 to perform a work task such as excavation. Alternatively, the operating room can be omitted and/or the work implement system 18 can be controlled automatically by the control system and/or remotely from the amphibious work vehicle 10. The illustrated vehicle is an excavator, but those of ordinary skill in the art will recognize from this disclosure that other types of vehicles can also be used in combination with the amphibious undercarriage system 14 discussed herein.

[0023] As seen in FIG. 2, the work implement system 18 is moveably attached to the vehicle body 12 so as to move between a plurality of different configurations with respect to the vehicle body 12. In the illustrated embodiment, the work implement system 18 includes a boom extension 20, an arm extension 22, and an excavating bucket 24. The boom extension 20 is coupled at a base end thereof to the vehicle body 12 in a pivotable manner. The boom extension 20 is also coupled at a distal end thereof to a base end of the arm extension 22 in a pivotable manner. The arm extension 22 is coupled at a distal end thereof to the excavating bucket 24 in a pivotable manner. Thus, each of the boom extension 20, the arm extension 22 and the excavating bucket 24 is movable with respect to the other components of the work implement system 18 in addition to being movable with respect to the vehicle body 12. As seen in FIG. 2, the work implement system 18 is dimensioned so that the excavating bucket 24 can extend above, forward of, rearward of or below the vehicle body 12 and the amphibious undercarriage system 14. In an example embodiment, the length of the boom extension 20 is approximately 7.75 meters (7,750 mm), the length of the arm extension 22 is approximately 5.15 meters (5,150 mm), and the excavating bucket 24 has a capacity of approximately 0.5 meters{circumflex over ()}3, but those of ordinary skill in the art will recognize from this disclosure that other dimensions are possible. Those of ordinary skill in the art will also recognize from this disclosure that alternative types of types of work implement systems can be used in combination with the amphibious undercarriage system 14 disclosed herein to perform other types of work in work areas including marshlands, swamps, inland lakes, rivers and shallow waters.

[0024] In the illustrated embodiment, the work implement system 18 also includes a plurality of hydraulic cylinders 26, 28 and 30 each having a piston that moves back and forth within a barrel to cause movement of the work implement system 18 between the various configurations. More specifically, the work implement system 18 includes a first hydraulic cylinder 26, a second hydraulic cylinder 28 and a third hydraulic cylinder 30. Here, the first hydraulic cylinder 26, the second hydraulic cylinder 28 and the third hydraulic cylinder 30 are disposed in one-to-one correspondence to the boom extension 20, the arm extension 22 and the excavating bucket 24. The first cylinder 26 drives the pivoting movement of the boom extension 20 with respect to the vehicle body 12. The second cylinder 28 drives pivoting movement of the arm extension 22 with respect to the boom extension 20. The third cylinder 30 drives pivoting movement of the excavating bucket 24 with respect to the arm extension 22. Thus, when the hydraulic cylinders 26, 28 and 30 are driven, the work implement system 18 is driven between its the various configurations, as seen for example in FIG. 2. Preferably, the first hydraulic cylinder 26 includes a pair of hydraulic cylinders 26, as seen for example in FIGS. 1 and 7. The operator controls the first hydraulic cylinder 26, the second hydraulic cylinder 28 and the third hydraulic cylinder 30 from the cab 16 using the control system for the amphibious work vehicle 12. In an embodiment, the hydraulic cylinders 26, 28 and 30 can be replaced and/or used in combination with other mechanisms for moving the boom extension 20, the arm extension 22 and the excavating bucket 24 with respect to each other and the vehicle body 12. For example, the hydraulic cylinders 26, 28 and 30 can be replaced and/or used in combination with one or more motors and/or gears that drive movement of the work implement system 18 and its components.

[0025] In the illustrated embodiment, the vehicle body 12 further includes a counterweight 32. As seen in FIGS. 1 and 2, the counterweight 32 is attached to a rear end of the vehicle body 12. The counterweight 32 can be attachable and detachable to and from the vehicle body 12 as needed to maintain stability, prevent tipping and reduce stress on components of the amphibious work vehicle 10 during operation, particularly when lifting heavy loads or working on uneven terrain, enabling the amphibious work vehicle 10 lift heavier loads in various work areas without compromising stability.

[0026] As best seen in FIG. 3, the illustrated amphibious undercarriage system 14 includes a first pontoon 34 and a second pontoon 36 that enable the amphibious work vehicle 10 to float atop a liquid body such as a marshland, a swamp, an inland lake, a river or another type of shallow water. More specifically, the first pontoon 34 and the second pontoon 36 are both buoyantly sealed to enable the work vehicle 10 to float atop the liquid body. The first pontoon 34 and the second pontoon 36 are located on the opposite lateral side of the amphibious work vehicle 10 to evenly disperse the amphibious work vehicle 10's weight above the liquid body. The first pontoon 34 has a first end 34A and a second end 36B, and the second pontoon 36 has a first end 36A and a second end 36B. The first ends 34A, 36A are the rear ends of the respective pontoons 34, 36, and the second ends 34B, 36B are the front ends of the respective pontoons 34, 36.

[0027] As further seen in FIG. 3, the amphibious undercarriage system 14 includes a first track chain 38 and a second track chain 40. The first track chain 38 extends around the length of the first pontoon 34, and the second track chain 40 extends around the length of the second pontoon 36. More specifically, the first track chain 38 is movably attached to the first pontoon 34 so as to travel around the first pontoon 34 in the length direction, and the second track chain 40 is movably attached to the second pontoon 36 so as to travel around the second pontoon 36 in the length direction. When the first track chain 38 and the second track chain 40 travel around the first pontoon 34 and the second pontoon 36, respectively, the first track chain 38 and the second track chain 40 drive the amphibious work vehicle 10 in the forward direction or the reverse direction across a land surface. The land surfaces can be above/outside the liquid body or below/within the liquid body. In an embodiment, the first track chain 38 and a second track chain 40 each include a plurality of track plates, which can be formed for example from ultra high molecular weight polyethylene.

[0028] As seen in FIG. 5, the amphibious undercarriage system 14 includes a drive system 42 configured to drive the first track chain 38 around the first pontoon 34 in both the forward and reverse directions and to drive the second track chain 40 around the second pontoon 36 in both the forward and reverse directions. Referring first to the first pontoon 34 side of the amphibious undercarriage system 14, the drive system 42 includes a first shaft 44 and a second shaft 46 for the first pontoon 34. The first shaft 44 is disposed at the first or rear end 34A of the first pontoon 34. The second shaft 46 is disposed at the second or forward end 34B of the first pontoon 34. The drive system 42 further includes a first hydraulic motor 48 and a second hydraulic motor 50 connected to the first shaft 44. The first and second hydraulic motors 48, 50 are disposed at the first or rear end 34A of the first pontoon 34. More specifically, the first hydraulic motor 48 and a second hydraulic motor 50 are attached on opposite lateral sides of the first shaft 44 at the first or rear end 34A of the first pontoon 34. The first hydraulic motor 48 and the second hydraulic motor 50 are configured to drive the first shaft 44, which drives the first track chain 38 around the first pontoon 34 to move the amphibious work vehicle 10 as discussed herein.

[0029] In the illustrated embodiment, the drive system 42 also includes a first bearing 52 and a second bearing 54. The first bearing 52 and the second bearing 54 are disposed on the second shaft 46. The first bearing 52 and the second bearing 54 facilitate rotation of the second shaft 46 with respect to the first pontoon 34 at the second or forward end 34B of the first pontoon 34. As seen for example in FIGS. 5 and 6, a hydraulic motor is not connected to the second shaft 46, the first bearing 52 or the second bearing 54.

[0030] As further seen in FIG. 6, the drive system 42 includes plurality of first sprockets 56 and a plurality of second sprockets 58. The plurality of first sprockets 56 are disposed on the first shaft 44. The plurality of second sprockets 58 are disposed on the second shaft 46. Each of the sprockets 56, 58 engages the first track chain 38. When the first hydraulic motor 48 and the second hydraulic motor 50 drive rotation of the first shaft 44, the rotation of the first shaft 44 causes the first track chain 38 to move around the first pontoon 34 through the engagement between the first plurality of sprockets 56 and the first track chain 38. The movement of the first track chain 38 causes rotation of the second shaft 46 through the engagement between the first track chain 38 and the second plurality of sprockets 58 and due to the rotation enabled by the bearings 52, 54. In the illustrated embodiment, the first shaft 44 is shown with three first sprockets 56, and the second shaft 46 is shown with three second sprockets 58, but those of ordinary skill in the art will recognize from this disclosure that any suitable number of first sprockets 56 and second sprockets 58 can be used.

[0031] As seen in FIG. 7, the drive system 42 also includes an electronic controller 60. The drive system 42 also includes a hydraulic circuit 62. The electronic controller 60 is configured to control the supply of hydraulic oil to components of the amphibious work vehicle 10 through the hydraulic circuit 62. The electronic controller 60 also controls the supply of hydraulic oil to the first hydraulic cylinder(s) 26, the second hydraulic cylinder(s) 28, and the bucket cylinder(s) 30. The electronic controller 60 further controls the supply of hydraulic oil to first and second pairs of hydraulic cylinders 64, 66 that are configured to rotate the vehicle body 12 through a swivel joint 68.

[0032] In an embodiment, the electronic controller 60 includes one or more of a processor, a memory, and a data transmission device. The processor is configured to execute instructions programmed into and/or stored by the memory. The memory can include, for example, a non-transitory storage medium. The data transmission device enables the electronic controller 60 to control various components of the amphibious work vehicle 10 and/or to enable communication with other sources. The data transmission device can include, for example, a transmitter and a receiver configured to send and receive wired or wireless signals in accordance with methods known in the art.

[0033] Referring again to FIGS. 3 and 5, the drive system 42 includes a swivel joint 68 and a frame 70. The swivel joint 68 is mounted on the frame 70 between the first pontoon 34 and the second pontoon 36. The swivel joint 68 is configured to rotate with respect to the frame 70 around the axis A in the center of frame 70. The vehicle body 12 is fixed to the swivel joint 68 so as to rotate with the swivel joint 68 with respect to the frame 70. The first pontoon 34 is disposed on one side of the swivel joint 68, and the second pontoon 36 is disposed on the opposite side of the swivel joint 68 in the lateral direction.

[0034] As further seen in FIG. 5, the frame 70 includes a support body 72, a first support member 74 and a second support member 76. The frame 70 extends between and connects the first support member 74 and the second support member 76. The first support member 74 extends between a first end 74A and a second end 74B. The second support member 76 also extends between a first end 76A and a second end 76B. The second support member 76 is disposed on the frame 70 forward of the first support member 74. The swivel joint 68 is mounted on the support body 72 of the frame 70 between the first support member 74 and the second support member 76.

[0035] As seen in FIGS. 1 to 3, the first pontoon 34 includes a first cavity 75 and a second cavity 77. The second pontoon 34 also includes a similar first cavity 75 and a similar second cavity 77. The first end 74A of the first support member 74 extends into the first cavity 75 of the first pontoon 34 to connect the frame 70 to the first pontoon 34. The first end 76A of the second support member 76 extends into the second cavity 77 of the first pontoon 34 to connect the frame 70 to the first pontoon 34. The first end 76A of the second support member 76 extends into the first cavity 75 of the second pontoon 36 to connect the frame 70 to the second pontoon 36. The second end 76B of the second support member 76 extends into the second cavity 77 of the second pontoon 36 to connect the frame 70 to the second pontoon 36.

[0036] In the illustrated embodiment, the first cavity 75 and the second cavity 77 are apertures that extend through the pontoons 34, 36 from the inner sides to the outer sides of the pontoons 34, 36. Alternatively, the first cavity 75 and the second cavity 77 can be cavities that extend into the inner side of the pontoons 34, 36 but not all the way through the pontoons 34, 36 to the outer sides. An advantage of structuring the first cavity 75 and the second cavity 77 as shown is that the pontoons 34, 36 can be positioned in either direction with respect to the support frame 70.

[0037] In the illustrated embodiment, the configuration of the support members 74, 76 and the cavities 75, 77 enables the amphibious undercarriage system 14 to alternate between a retracted configuration and an extended configuration. That is, the support members 74, 76 can be adjusted to different positions within the cavities 75, 77 to adjust the lateral width of the amphibious undercarriage system 14 from the outer surface of the first pontoon 34 to the outer surface of the second pontoon 36.

[0038] FIG. 8 illustrates example embodiments of a fully retracted configuration and a fully extended configuration for the amphibious undercarriage system 14. In an embodiment, the amphibious undercarriage system 14 can also be placed in one or more partially retracted/extended configurations between the fully retracted configuration and the fully extended configuration.

[0039] In FIG. 8, the distance (A) between the centers of the pontoons 34, 36 in the retracted configuration is 2.76 meters (2,760 mm), and the distance (A1) between the centers of the pontoons 34, 36 in the extended configuration is 4.02 meters (4,020 mm). The distance (F) between the inner sides of the pontoons 34, 36 in the retracted configuration is 1.17 meters (1,170 mm), and the distance (F1) between the inner sides of the pontoons 34, 36 in the extended configuration is 2.44 meters (2,440 mm). The distance (G) between the outer sides of the pontoons 34, 36 in the retracted configuration is 4.575 meters (4,575 mm), and the distance (G1) between the outer sides of the pontoons 34, 36 in the extended configuration is 5.185 meters (5,815 mm). The width (O) of the cab 16 is 2.90 meters (2,900 mm), the width (E) of each track chain 38, 40 is 1.59 meters (1,590 mm), and the width (E1) of each pontoon 34, 36 is 1.62 meters (1620 mm). Thus, in the illustrated embodiment, the amphibious work vehicle 10 can expand or retract its lateral width by over 1.4.

[0040] As further seen in FIG. 8, in the illustrated embodiment, the height (H) from the top of the cab 12 to the bottom of the track chains 38, 40 is 4.05 meters (4,050 mm), the ground clearance (I) of the counterweight 32 is 2.215 meters (2,215 mm), the minimum ground clearance (J) between the bottom of the frame 70 and the bottom of the track chains is 1.25 meters (1,250 mm), the shoe setting height (K) between the top of the track chains 38, 40 and the bottom of the track chains 38, 40 is 2.030 meters (2,030 mm), and the crawler height (L) between the top of the cab 12 and the bottom of the track chains 38, 40 is 2.215 meters (2,215 mm). As further seen in FIG. 2, in the illustrated embodiment, the total track length (B) of the track chains 38, 40 is 9.375 meters (9,375 mm), the distance (C) between idler and sprocket is 8.66 meters (8,660 mm), the length (D) of the track chains 38, 40 on hard ground is 5.70 meters (5,700 mm), the length (D1) of the track chains 38, 40 on soft ground is 7.735 meters (7,735 mm), the water line level (M) is 1.62 meters (1,620 mm) above the bottom of the track chains 38, 40, and the swing radius (N) of the vehicle body 12 is 2.75 meters (2,750 mm). It has been determined that these dimensions stably support the amphibious work vehicle 10 in both the retracted configuration and the extended configuration, but those of ordinary skill in the art will recognize from this disclosure that other dimensions can be used.

[0041] As further seen in FIG. 2, the illustrated dimensions enable an extended working range for the work implement system 18. In the illustrated embodiment, the work implement system 18 has a maximum digging height (a) of 14.36 meters (14,360 mm), a maximum dumping height (b) of 12.26 meters (12,260 mm), a maximum digging depth (c) of 8.25 meters (8,250 mm), a maximum digging reach (d) of 13.50 meters (13,500 mm), a maximum ground digging reach (e) of 13.25 meters (13,250 mm), and a total length (f) during parking of 13.045 meters (13,045 mm). Thus, in the illustrated embodiment, the amphibious work vehicle 10 can operate in liquid work areas with a digging height over 6.4 the height of the amphibious undercarriage system 14 and over 3.5 the height of the vehicle body 12, a forward reach over 1.4 the length of the amphibious undercarriage system 14, and a digging depth over 3.7 the height of the amphibious undercarriage system 14 and over 2.0 the height of the vehicle body 12.

[0042] Referring again to FIG. 5, the drive system 42 includes a first hydraulic oil line 78, a second hydraulic line 79, and a third hydraulic oil line 80. The first hydraulic line 78 is attached to the frame 70 and operatively connected to a main control valve (MCV) of the controller 60. The second hydraulic oil line 79 is connected to the first hydraulic motor 48. The third hydraulic oil line 80 is connected to the second hydraulic motor 50. More specifically, the second hydraulic oil line 79 extends from the first hydraulic oil line 78 to the first hydraulic motor 48, and the third hydraulic oil line 80 extends from the first hydraulic oil line 78 to the second hydraulic motor 50. The controller 60 controls the MCV to cause hydraulic oil to flow through the first hydraulic oil line 78 to the first hydraulic motor 48 via the second hydraulic oil line 79 and to the second hydraulic motor 50 via the third hydraulic line 80. By structuring the MCV, the hydraulic oil lines 78, 79, 80 and hydraulic motors 48, 50 in this way, the design creates shorter distances and less resistance for hydraulic oil to flow and energize the hydraulic motor. This design also makes the hydraulic motor response time faster and synchronizes movement. This design further produces uniform torque and even traction on the first track chain 38, which improves the lifespan of the first track chain 38 and sprockets 56, 58.

[0043] The second pontoon 36 side is configured substantially similarly to the first pontoon 34 side. On the second pontoon 36 side, the drive system 42 includes a third shaft 82 and a fourth shaft 88 for the second pontoon 36. The third shaft 82 is disposed at the first or rear end 36A of the second pontoon 36. The fourth shaft 88 is disposed at the second or forward end 36B of the second pontoon 36. The drive system 42 further includes a third hydraulic motor 84 and a fourth hydraulic motor 86 connected to the third shaft 82. The third and fourth hydraulic motors 84, 86 are disposed at the first or rear end 36A of the second pontoon 36. More specifically, the third hydraulic motor 84 and the fourth hydraulic motor 86 are attached on opposite lateral sides of the third shaft 82 at the first or rear end 36A of the second pontoon 36. The third hydraulic motor 84 and the fourth hydraulic motor 86 are configured to drive the third shaft 82, which drives the second track chain 40 around the second pontoon 36 to move the amphibious work vehicle 10 as discussed herein.

[0044] In the illustrated embodiment, the drive system 42 also includes a third bearing 90 and a fourth bearing 92. The third bearing 90 and the fourth bearing 92 are disposed on the fourth shaft 88. The third bearing 90 and the fourth bearing 92 facilitate rotation of the fourth shaft 88 with respect to the second pontoon 36 at the second or forward end 36B of the second pontoon 36. As seen for example in FIG. 6, a hydraulic motor is not connected to the fourth shaft 88, the third bearing 90 or the fourth bearing 92.

[0045] The third shaft 82 and the fourth shaft 88 can also include sprockets 56, 58 as with those for the first shaft 44 and the second shaft 46. That is, a plurality of first sprockets 56 are disposed on the third shaft 82, and a plurality of second sprockets 58 are disposed on the fourth shaft 88. Each of the sprockets 56, 58 engages the second track chain 40. When the third hydraulic motor 84 and the fourth hydraulic motor 86 drive rotation of the third shaft 82, the rotation of the third shaft 82 causes the second track chain 40 to move around the second pontoon 36 through the engagement between the first plurality of sprockets 56 and the second track chain 40. The movement of the second track chain 40 causes rotation of the fourth shaft 88 through the engagement between the second track chain 40 and the second plurality of sprockets 58 and due to the rotation enabled by the bearings 90, 92. In the illustrated embodiment, the third shaft 82 is shown with three first sprockets 56, and the fourth shaft 88 is shown with three second sprockets 58, but those of ordinary skill in the art will recognize from this disclosure that any suitable number of first sprockets 56 and second sprockets 58 can be used.

[0046] Referring again to FIG. 5, the drive system 42 also includes a fourth hydraulic oil line 94, a fifth hydraulic oil line 95, and a sixth hydraulic oil line 96. The fourth hydraulic line 94 is attached to the frame 70 and operatively connected to the MCV of the controller 60. The fifth hydraulic oil line 95 is connected to the third hydraulic motor 84. The sixth hydraulic oil line 96 is connected to the fourth hydraulic motor 86. More specifically, the fifth hydraulic oil line 95 extends from the fourth hydraulic oil line 94 to the third hydraulic motor 84, and the sixth hydraulic oil line 96 extends from the fourth hydraulic oil line 94 to the fourth hydraulic motor 86. The controller 60 controls the MCV to cause hydraulic oil to flow through the fourth hydraulic oil line 94 to the third hydraulic motor 84 via the fifth hydraulic oil line 95 and to the fourth hydraulic motor 86 via sixth third hydraulic line 96. As discussed above, by structuring the MCV, the hydraulic oil lines 94, 95, 96 and hydraulic motors 84, 86 in this way, the design creates shorter distances and less resistance for hydraulic oil to flow and energize the hydraulic motor, makes the hydraulic motor response time faster and synchronizes movement, and further produces uniform torque and even traction on the second track chain 40, which improves the lifespan of the second track chain 40 and sprockets 56, 58.

[0047] The drive system 42 of the amphibious work vehicle 10 is a rear-wheel drive system that increases stability and provides more power. The hydraulic motors 48, 50 of the first pontoon 34 and the hydraulic motors 84, 86 of the second pontoon 36 are disposed at the first or rear ends 34A, 36A of the respective pontoons 34, 36. In other words, each of the hydraulic motors 48, 50, 84, 86 is disposed at a rear end of the amphibious undercarriage system 14. This configuration focuses the force generated by the hydraulic motors 48, 50, 84, 86 in one area and generates more power while moving in difficult terrain, such as in a swampy environment or climbing uphill. Additionally, as further discussed above, the hydraulic circuit provides a shorter distance and less resistance for the hydraulic oil to flow and energize the hydraulic motors 48, 50, 84, 86. This configuration allows the hydraulic motors 48, 50, 84, 86 to respond more quickly and to facilitate synchronization between the hydraulic motors 48, 50, 84, 86. The drive system 42 further produces substantially uniform torque and even traction on the track chains 38, 40, which increases the life span of the track chains 38, 40 and sprockets 56, 58.

[0048] In the illustrated embodiment, the drive system 42 of the amphibious work vehicle 10 includes only four hydraulic motors 48, 50, 84 and 86. Thus, in this embodiment, the drive system 42 of the amphibious work vehicle 10 includes only two motors disposed at each rear axle.

[0049] In the illustrated embodiment, the drive system 42 provides two hydraulic motors on each shaft 44, 82 at the rear end 34A, 36A of each pontoon 34, 36, and two bearings 52, 54, 90, 92 on each shaft 46, 88 at the forward end 34B, 36B of each pontoon 34, 36. This configuration provides less tension for the components of the drive system 42. The bearings 52, 54, 90, 92 connected to the shafts 46, 88 at the forward end 34B, 36B of each pontoon 34, 36 move freely with a minimal amount of tension, thereby increasing the life span of the hydraulic motors 48, 50, 84, 86 and the bearings 52, 54, 90, 92.

[0050] The embodiments described herein provide an amphibious undercarriage system and an amphibious work vehicle configured for use in work areas such as marshlands, swamps, inland lakes, rivers and shallow waters. These systems are advantageous, for example, due to their versatility and increased lifespan due to the configuration of their components. It should be understood that various changes and modifications to the systems and methods described herein will be apparent to those skilled in the art and can be made without diminishing the intended advantages. The foregoing detailed description of the certain exemplary embodiments has been provided for the purpose of explaining the principles and practical applications, thereby enabling others skilled in the art to understand various exemplary embodiments and with various modifications as are suited to a particular use contemplated. This description is not necessarily intended to be exhaustive or to limit the invention to the exemplary embodiments disclosed. Accordingly, additional embodiments are possible and are intended to be encompassed within this specification and the scope of the appended claims. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way.

General Interpretation of Terms

[0051] In understanding the scope of the present invention, the term comprising and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, including, having and their derivatives. Also, the terms part, section, portion, member or element when used in the singular can have the dual meaning of a single part or a plurality of parts unless otherwise stated.

[0052] The term configured as used herein to describe a component, section or part of a device or element includes hardware and/or software that is constructed and/or programmed to carry out the desired function.

[0053] The terms of degree such as generally, substantially, about and approximately as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed.

[0054] Also, it will be understood that although the terms first and second may be used herein to describe various components, these components should not be limited by these terms. These terms are only used to distinguish one component from another. Thus, for example, a first component discussed above could be termed a second component and vice versa without departing from the teachings of the present disclosure. The term attached or attaching, as used herein, encompasses configurations in which an element is directly secured to another element by affixing the element directly to the other element; configurations in which the element is indirectly secured to the other element by affixing the element to the intermediate member(s) which in turn are affixed to the other element; and configurations in which one element is integral with another element, i.e. one element is essentially part of the other element. This definition also applies to words of similar meaning, for example, joined, connected, coupled, mounted, bonded, fixed and their derivatives. Finally, terms of degree such as substantially, about and approximately as used herein mean an amount of deviation of the modified term such that the end result is not significantly changed.

[0055] While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. For example, unless specifically stated otherwise, the size, shape, location or orientation of the various components can be changed as needed and/or desired so long as the changes do not substantially affect their intended function. Unless specifically stated otherwise, components that are shown directly connected or contacting each other can have intermediate structures disposed between them so long as the changes do not substantially affect their intended function. The functions of one element can be performed by two, and vice versa unless specifically stated otherwise. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such feature(s). Thus, the foregoing descriptions of the exemplary embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.