JP6768599B2 - Axle device and work vehicle - Google Patents

Description

The present invention is an axle device provided with a rolling fulcrum shaft that is mounted over a support portion provided on a vehicle body and a connecting hole of a wheel drive case to support the wheel drive case on the vehicle body so as to be rollable, and an axle thereof. Regarding a work vehicle equipped with a device.

In the axle device described above, the wheel drive case is capable of rolling with respect to the vehicle body with the rolling fulcrum shaft as the rolling fulcrum. As an axle device of this type, for example, there is one shown in Patent Document 1. The one shown in Patent Document 1 includes a rolling shaft which is arranged on a front axle case and a front wheel support frame fixed to an engine frame and which fits a fulcrum receiving portion in the middle of the left and right widths of the front axle case. ing.

Japanese Unexamined Patent Publication No. 2008-179331

In the axle device described above, the wheel drive case can be smoothly rolled by providing a bush that is internally fitted into the connecting hole of the wheel drive case and externally fitted to the rolling fulcrum shaft. However, if a special refueling channel that allows refueling to the bush is provided, the cost will be high. Further, even if a special refueling path is provided, it is difficult to refuel because the support structure of the wheel drive case is located at the bottom of the vehicle body.

The present invention provides an axle device and a work vehicle capable of refueling a bush at low cost and without any special effort.

The axle device according to the present invention
A rolling fulcrum shaft that is mounted over a support portion provided on the vehicle body and a connecting hole of the wheel drive case to support the wheel drive case on the vehicle body so as to be rollable.
A bush that is internally fitted into the connecting hole and externally fitted to the rolling fulcrum shaft,
A breather circuit that communicates the differential mechanism chamber in which the differential mechanism of the wheel drive case is housed to the outside of the wheel drive case is provided.
The breather circuit is provided with a circuit unit for communicating the differential mechanism chamber and the connecting hole .
The circuit unit is a circuit unit in the first case bored in the wheel drive case.
The breather circuit is formed in the wheel drive case, the circuit portion in the second case that communicates the connecting hole to the outside of the wheel drive case, and the peripheral surface of the connecting hole, and is formed in the peripheral surface of the connecting hole. It is provided with an annular groove for communicating the inner circuit portion and the second case inner circuit portion .

According to this configuration, when the internal pressure of the differential mechanism chamber rises, the inside air of the differential mechanism chamber blows out to the outside of the wheel drive case through the breather circuit. At this time, the lubricating oil stored in the differential mechanism chamber may flow out to the breather circuit together with the exhaust gas. Lubricating oil that has flowed out into the breather circuit infiltrates from the circuit portion to the outer peripheral side of the bush.

Therefore, the busher circuit and the exhaust gas can be utilized as the refueling means to refuel the bush at low cost, and no special refueling labor is required.

According to this configuration, the part of the breather circuit used for refueling the bush can be compactly formed inside the wheel drive case.

In the present invention, it is preferable that the outer peripheral surface of the bush is provided with an outer peripheral groove, and the outer peripheral groove is communicated with the circuit portion in the first case and the circuit portion in the second case.

According to this configuration, since the circuit portion in the first case and the circuit portion in the second case are connected by the outer peripheral groove of the bush, the exhaust gas and the intake air in the differential mechanism chamber are likely to flow. Further, the lubricating oil that has flowed into the circuit portion inside the first case from the differential mechanism chamber flows into the outer peripheral groove from the circuit portion inside the first case, and flows from the outer peripheral groove to the outer peripheral side of the bush, so that the lubricating oil flows to the outer peripheral side of the bush. Oil is easy to turn.

In the present invention, it is preferable that the circuit portion in the first case and the circuit portion in the second case are aligned in a straight line with the rolling fulcrum axis in between.

According to this configuration, the inside of the circuit part in the first case and the inside of the second case are drilled in a straight line from the end opposite to the rolling fulcrum shaft side of the circuit part in the second case toward the circuit part in the first case. The circuit section can be formed at once.

Another axle device according to the invention is
A rolling fulcrum shaft that is mounted over a support portion provided on the vehicle body and a connecting hole of the wheel drive case to support the wheel drive case on the vehicle body so as to be rollable.
A bush that is internally fitted into the connecting hole and externally fitted to the rolling fulcrum shaft,
A breather circuit that communicates the differential mechanism chamber in which the differential mechanism of the wheel drive case is housed to the outside of the wheel drive case is provided.
The breather circuit is provided with a circuit unit for communicating the differential mechanism chamber and the connecting hole.
The bush, communicated with the outside and the inside of the bush, and that has a through hole provided in communication with the circuit portion.

According to this configuration, the lubricating oil that has flowed into the circuit section from the differential mechanism chamber enters the inner peripheral side of the bush through the through hole, so that the inner peripheral side of the bush can also be lubricated.

Another axle device according to the invention is
A rolling fulcrum shaft that is mounted over a support portion provided on the vehicle body and a connecting hole of the wheel drive case to support the wheel drive case on the vehicle body so as to be rollable.
A bush that is internally fitted into the connecting hole and externally fitted to the rolling fulcrum shaft,
A breather circuit that communicates the differential mechanism chamber in which the differential mechanism of the wheel drive case is housed to the outside of the wheel drive case is provided.
The breather circuit is provided with a circuit unit for communicating the differential mechanism chamber and the connecting hole.
The bush is provided with a through hole that communicates the outside and the inside of the bush and communicates with the circuit portion.
An inner peripheral groove is provided on the inner peripheral surface of the bush.
It said through hole and said inner peripheral grooves that have been communicated.

According to this configuration, the lubricating oil that has flowed into the circuit section from the differential mechanism chamber flows into the inner peripheral groove of the bush through the through hole, and flows from the inner peripheral groove to the inner peripheral side of the bush. Lubricating oil easily turns to the side.

In the present invention, it is preferable that the breather circuit has a function of supplying grease to the bush.

According to this configuration, it is possible to supply grease to the bush by utilizing the breather circuit in the grease supply path.

The work vehicle according to the present invention includes the axle device according to any one of claims 1 to 6 .

According to this configuration, the busher can be refueled by utilizing the brazer circuit and the exhaust as the refueling means, so that a work vehicle in which the wheel drive case rolls smoothly can be obtained inexpensively and easily.

The left side showing the entire tractor. It is a perspective view which shows the wheel drive case. It is a front view which shows the wheel drive case in the state supported by the vehicle body. It is a vertical sectional side view which shows the support structure of a wheel drive case. It is sectional drawing which shows the breather circuit. FIG. 3 is a perspective view showing a bush having another implementation structure. It is a developed view of the outer peripheral surface of the bush provided with another implementation structure. It is a development view of the inner peripheral surface of a bush provided with another implementation structure.

Hereinafter, a case where the embodiment of the present invention is applied to a tractor as an example of a work vehicle will be described with reference to the drawings. FIG. 1 is a left side view showing the entire tractor. The direction [F] shown in FIG. 1 is the front direction of the traveling vehicle body T, the direction [B] is the rear direction of the traveling vehicle body T, the direction on the front side of the paper is the left direction of the traveling vehicle body T, and the direction on the back side of the paper is the traveling vehicle body T. Is defined as the right direction of.

As shown in FIG. 1, the tractor is equipped with a pair of left and right front wheels 1 for steering operation and driveability, and a pair of left and right rear wheels 2 for driveability, and is configured to be self-propelled. It has. A driving unit 3 is formed at the front portion of the traveling vehicle body T. The driving unit 3 is provided with an engine 4 that outputs the driving force of the front wheels 1 and the rear wheels 2. A boarding-type driving unit 5 is formed on the rear side of the traveling vehicle body T. The driving unit 5 is covered by the cabin 6. The link mechanism 7 extends rearward from the rear portion of the traveling vehicle body T so as to be vertically swingable.

In the tractor, a passenger-type cultivator can be configured by connecting a rotary cultivator (not shown) to the rear portion of the traveling vehicle body T so as to be able to move up and down by a link mechanism 7. In the tractor, various passenger-type work machines can be configured by connecting various work devices to the rear portion of the vehicle body so as to be able to move up and down.

As shown in FIG. 1, the vehicle body frame F of the tractor includes an engine 4, a front frame 8 extending from the engine 4 toward the front of the vehicle body, and a mission case 9 in which the front portion is connected to the rear portion of the engine 4. I have. The transmission case 9 contains a transmission (not shown) that shifts the power from the engine 4 and transmits it to the front wheels 1 and the rear wheels 2. The left and right front wheels 1 are supported by the front frame 8 of the traveling vehicle body T via an axle device K.

[Axle device K configuration]
As shown in FIGS. 2, 3 and 4, the axle device K includes a wheel drive case 10 and a rolling fulcrum shaft 21.

As shown in FIGS. 3 and 4, the front frame 8 is formed with three support portions 11, 12, and 13 arranged at intervals in the front-rear direction of the traveling vehicle body T. The three support portions 11, 12, 13 are integrally formed with a connecting member 14 that connects the three support portions 11, 12, 13. The three support portions 11, 12, and 13 are formed on the front frame 8 by fixing the connecting member 14 to the front frame 8 with connecting bolts.

As shown in FIGS. 2, 3 and 4, two connecting portions 15 and 16 arranged at intervals in the front-rear direction of the vehicle body are formed in the central portion 10a of the wheel drive case 10 in the lateral width direction of the vehicle body. The two connecting portions 15 and 16 project upward from the upper part of the wheel drive case 10. The front connecting portion 15 of the two connecting portions 15 and 16 is integrally formed with the wheel drive case 10.
The rear connecting portion 16 of the two connecting portions 15 and 16 is integrally formed with the lid case portion 17 of the wheel drive case 10. The lid case portion 17 is detachably attached to the rear portion of the wheel drive case 10 by a connecting bolt 18 and closes the differential mechanism chamber 19 formed inside the wheel drive case 10.

As shown in FIGS. 3 and 4, the tubular connecting member 20 is mounted over the connecting hole of the front connecting portion 15 and the supporting hole of the frontmost supporting portion 11 among the three supporting portions 11, 12, 13. Has been done.
Rolling fulcrum shaft 21 over the connecting holes 16a of the rear connecting portion 16 and the supporting holes of the two supporting portions 12, 13 located on the front and rear sides of the rear connecting portion 16 among the three supporting portions 11, 12, 13. Is installed. As shown in FIG. 5, a bush 40 is interposed between the connecting portion 16 and the rolling fulcrum shaft 21. The bush 40 is internally fitted in the connecting hole 16a and externally fitted in the rolling fulcrum shaft 21. A pin member 22 is mounted over the rolling fulcrum shaft 21 and the rearmost support portion 13. The pin member 22 prevents the rolling fulcrum shaft 21 from coming off. The wheel drive case 10 is supported by the front frame 8 via the rolling fulcrum shaft 21, the connecting member 20, and the three support portions 11, 12, and 13, and the traveling vehicle body uses the shaft core R of the rolling fulcrum shaft 21 as the rolling shaft core. It is possible to roll with respect to T.

As shown in FIGS. 2 and 3, front wheel support portions 23 are provided at both ends of the wheel drive case 10 in the lateral width direction. The left and right front wheel support portions 23 are provided with a plurality of connecting bolts 24 arranged in the circumferential direction of the front wheels 1, and are configured to support the front wheels 1 by tightening and connecting with the connecting bolts 24 so as not to rotate relative to each other. The left and right front wheels 1 are divided and supported by both lateral ends of the wheel drive case 10 and supported by the front frame 8 via the wheel drive case 10, and the axis R of the rolling fulcrum axis 21 is the rolling axis. It is possible to roll with respect to the traveling vehicle body T.

As shown in FIGS. 2 and 3, the left and right front wheel support portions 23 are supported by the wheel drive case 10 via the steering fulcrum portion 25. The left and right front wheel support portions 23 are rotatably supported by the steering fulcrum portion 25. The left and right front wheels 1 are supported by the wheel drive case 10 via the front wheel support portion 23 and the steering fulcrum portion 25, and are rotatably supported by the wheel drive case 10 with the axle core 1a as the center of rotation. As shown in FIG. 4, the differential mechanism 26 is housed in the differential mechanism chamber 19 of the wheel drive case 10. As shown in FIG. 3, the reduction mechanism 27 is housed in the left and right front wheel support portions 23. Power from the traveling transmission is transmitted to the input shaft 26a (see FIGS. 2 and 4) of the differential mechanism 26 via the rotating shaft 28 (see FIG. 1). The left and right outputs of the differential mechanism 26 are input to the left and right reduction mechanism 27 via the rotation shaft 29 (see FIG. 3), the front wheel support portion 23 is rotationally driven by the output of the reduction mechanism 27, and the left and right front wheels 1 are It is driven with the axle core 1a as the center of rotation.

As shown in FIGS. 2 and 3, the left and right steering fulcrum portions 25 are supported by the wheel drive case 10 via the steering fulcrum shaft 30, and swing with the shaft core S of the steering fulcrum shaft 30 as the steering shaft core. It is movably supported. A pair of left and right cylinder support portions 31 are formed at the front portion of the central portion of the wheel drive case 10. The steering cylinder 32 is supported by the left and right cylinder support portions 31. The cylinder rod 32a of the steering cylinder 32 and the knuckle arms 25a of the left and right steering fulcrum portions 25 are interlocked and connected by the connecting shaft 33. By rotating the steering wheel 34 (see FIG. 1), the steering cylinder 32 is operated, and the steering fulcrum portion 25 is swung by the cylinder rod 32a. As a result, the left and right front wheels 1 swing in the swing direction corresponding to the rotation direction of the steering wheel 34 with the shaft core S as the steering shaft core, and swing by the turning angle corresponding to the rotation operation amount of the steering wheel 34. Will be done.

[Structure of breather circuit 35]
As shown in FIGS. 4 and 5, the breather circuit 35 is connected to the differential mechanism chamber 19. The differential mechanism chamber 19 is communicated to the outside of the wheel drive case 10 by the breather circuit 35, and is exhausted to the outside of the wheel drive case 10 via the breather circuit 35, or is exhausted to the outside of the wheel drive case 10 via the breather circuit 35. Inhale from.

As shown in FIGS. 4 and 5, the breather circuit 35 includes a first case inner circuit portion 36, an annular groove 37, a second case inner circuit portion 38, and a breather pipe 39. The circuit portion 36 in the first case is bored in a portion of the rear connecting portion 16 in the wheel drive case 10 on the side where the differential mechanism chamber 19 is located with respect to the rolling fulcrum shaft 21. The circuit unit 36 in the first case constitutes a circuit unit that communicates the differential mechanism chamber 19 of the breather circuit 35 with the connecting hole 16a.

The circuit portion 38 in the second case is bored in a portion of the rear connecting portion 16 in the wheel drive case 10 on the side opposite to the side where the differential mechanism chamber 19 is located with respect to the rolling fulcrum shaft 21. The circuit unit 38 in the second case constitutes a circuit unit that communicates the connecting hole 16a in the breather circuit 35 with the outside of the wheel drive case 10.

The circuit portion 36 in the first case and the circuit portion 38 in the second case are arranged in a straight line with the rolling fulcrum shaft 21 interposed therebetween. The second case inner circuit part 38 and the first case inner circuit part are drilled in a straight line from the end opposite to the rolling fulcrum shaft side of the second case inner circuit part 38 toward the first case inner circuit part 36. 36 can be formed at once.

The annular groove 37 is formed on the inner peripheral surface of the connecting hole 16a. The annular groove 37 and the opening of the circuit portion 36 in the first case to the connecting hole 16a overlap. The annular groove 37 and the opening of the circuit portion 38 in the second case to the connecting hole 16a overlap. The circuit portion 36 in the first case and the circuit portion 38 in the second case are communicated with each other by the annular groove 37.

The bush 40 is provided with a through hole 41. The through hole 41 is provided so as to communicate with the inside of the bush 40, the outside of the bush 40, and the annular groove 37. The inside of the bush 40 is communicated with the circuit portion 36 in the first case by a through hole 41.

The breather pipe 39 extends from the circuit portion 38 in the second case to a portion of the traveling vehicle body T that forms an exhaust port (not shown) of the breather circuit 35.

When the internal pressure of the differential mechanism chamber 19 rises, the inside air of the differential mechanism chamber 19 blows out to the outside of the wheel drive case 10 through the breather circuit 35. At this time, the lubricating oil stored in the differential mechanism chamber 19 may flow out to the breather circuit 35 together with the exhaust gas. The lubricating oil that has flowed out to the breather circuit 35 flows into the annular groove 37 from the circuit portion 36 in the first case and infiltrates the outer peripheral side of the bush 40, and passes through the through hole 41 from the circuit portion 36 in the first case to the bush 40. Invades the inner circumference side of. The breather circuit 35 can be used as a refueling means to refuel the bush 40.

The breather circuit 35 has a grease supply function to the bush 40, and the breather circuit 35 can be used as a supply path for supplying grease to the bush 40.
That is, the circuit portion 38 in the second case and the breather pipe 39 are connected via the connecting pipe 42. The connecting pipe 42 is supported by the connecting portion 16. By removing the breather pipe 39 from the connecting pipe 42, the grease gun can be connected to the connecting pipe 42, and grease can be supplied to the bush 40 through the circuit portion 38 in the second case, the annular groove 37, and the through hole 41.

[Another Embodiment]
(1) FIG. 6 is a perspective view showing a bush 45 having another implementation structure. In the bush 45 having another implementation structure, the outer peripheral surface 45a is provided with the outer peripheral groove 46, and the inner peripheral surface 45b is provided with the inner peripheral groove 47.

FIG. 7 is a developed view of the outer peripheral surface 45a of the bush 45. As shown in FIG. 7, the outer peripheral groove 46 is communicated with the annular groove 37 of the connecting hole 16a, and is communicated with the first case inner circuit portion 36 and the second case inner circuit portion 38 via the annular groove 37. The lubricating oil that has flowed from the differential mechanism chamber 19 into the circuit portion 36 in the first case flows into the outer peripheral groove 46. Lubricating oil from the differential mechanism chamber 19 can be supplied from the outer peripheral groove 46 to the outer peripheral side of the bush 45. In the present embodiment, the outer peripheral groove 46 is configured to communicate with the first case inner circuit portion 36 and the second case inner circuit portion 38 via the annular groove 37, but does not include the annular groove 37 and is the first. A configuration that directly communicates with the in-case circuit unit 36 and the second in-case circuit unit 38 may be adopted. In the present embodiment, the linear outer peripheral groove 46 is adopted, but a zigzag outer peripheral groove can be adopted.

FIG. 8 is a developed view of the inner peripheral surface 45b of the bush 45. As shown in FIG. 8, the inner peripheral surface 45b is provided with two inner peripheral grooves 47. Of the two inner peripheral grooves 47, one inner peripheral groove 47 at the central portion in the width direction of the bush 45 is formed in a straight line, and the inner circumference of the other one of the two inner peripheral grooves 47 is formed. The groove 47 is formed in a zigzag shape. The two inner peripheral grooves 47 are communicated with a through hole 48 that communicates the outside and the inside of the bush 45, and are communicated with the outer peripheral side (connecting hole 16a) of the bush 45 via the through hole 48. The lubricating oil that has flowed from the differential mechanism chamber 19 through the circuit portion 36 in the first case to the outer peripheral side of the bush 45 flows into the inner peripheral groove 47 through the through hole 48. Lubricating oil from the differential mechanism chamber 19 can be supplied from the inner peripheral groove 47 to the inner peripheral side of the bush 45. In the present embodiment, four through holes 48 are provided, but three or less or five or more through holes may be provided. In the present embodiment, the linear and zigzag inner peripheral grooves 47 are provided, but the inner peripheral groove may be provided only in a straight line or in a zigzag shape.

(2) In the above-described embodiment, an example is shown in which the through holes 41, 48 and the inner peripheral groove 47 are provided and oil is supplied to the inner peripheral side of the bushes 40, 45, but the bushes 40 and 45 are fixed to the rolling fulcrum shaft 21. In the case of the bush, it is sufficient to adopt a configuration in which the through holes 41 and 48 and the inner peripheral groove 47 are not provided and oil is supplied only to the outer peripheral side of the bushes 40 and 45.

(3) In the above-described embodiment, the axle device K is configured to support the front wheel 1, but the axle device K may be configured to support the rear wheel 2.

(4) In the above-described embodiment, an example is shown in which the wheel drive case 10 is configured to support the front wheel 1 so as to be steerable and swingable. It may be configured to support in a state.

(5) In the above-described embodiment, an example is shown in which the circuit unit 36 in the first case and the circuit unit 38 in the second case are arranged in a straight line, but the flow directions of both circuit units intersect. It may be formed and carried out in a state.

(6) In the above embodiment, the example in which the connecting portion 16 is integrally formed with the lid case portion 17 is shown, but the connecting portion 16 is integrally formed with a portion of the wheel drive case 10 different from the lid case portion 17. It may be carried out.

The present invention is not limited to a tractor having front wheels and rear wheels, and can be applied to a tractor having a mini crawler instead of the rear wheels. It can also be applied to various work vehicles such as transport vehicles.

10 Wheel drive case 12 Support part 13 Support part 16a Connection hole 19 Differential mechanism room 21 Rolling fulcrum shaft 26 Differential mechanism 36 Circuit part (Circuit part in the first case)
37 Circular groove 38 Second case inner circuit part 40 Bush 45 Bush 45a Outer peripheral surface 45b Inner peripheral surface 41 Through hole 46 Outer peripheral groove 47 Inner peripheral groove 48 Through hole T Traveling vehicle body

Claims (7)

A rolling fulcrum shaft that is mounted over a support portion provided on the vehicle body and a connecting hole of the wheel drive case to support the wheel drive case on the vehicle body so as to be rollable.
A bush that is internally fitted into the connecting hole and externally fitted to the rolling fulcrum shaft,
A breather circuit that communicates the differential mechanism chamber in which the differential mechanism of the wheel drive case is housed to the outside of the wheel drive case is provided.
The breather circuit is provided with a circuit unit for communicating the differential mechanism chamber and the connecting hole .
The circuit unit is a circuit unit in the first case bored in the wheel drive case.
The breather circuit is formed in the wheel drive case, the circuit portion in the second case that communicates the connecting hole to the outside of the wheel drive case, and the peripheral surface of the connecting hole, and is formed in the peripheral surface of the connecting hole. An axle device provided with an annular groove for communicating the inner circuit portion and the second case inner circuit portion . An outer peripheral groove is provided on the outer peripheral surface of the bush.
The peripheral groove, axle transmission according to claim 1, which is communicated with the circuit portion in the first case and the second case in the circuit portion. The axle device according to claim 1 or 2 , wherein the circuit portion in the first case and the circuit portion in the second case are aligned in a straight line with the rolling fulcrum shaft in between. A rolling fulcrum shaft that is mounted over a support portion provided on the vehicle body and a connecting hole of the wheel drive case to support the wheel drive case on the vehicle body so as to be rollable.
A bush that is internally fitted into the connecting hole and externally fitted to the rolling fulcrum shaft,
A breather circuit that communicates the differential mechanism chamber in which the differential mechanism of the wheel drive case is housed to the outside of the wheel drive case is provided.
The breather circuit is provided with a circuit unit for communicating the differential mechanism chamber and the connecting hole.
An axle device provided with a through hole that allows the bush to communicate with the outside and the inside of the bush and also communicate with the circuit portion . A rolling fulcrum shaft that is mounted over a support portion provided on the vehicle body and a connecting hole of the wheel drive case to support the wheel drive case on the vehicle body so as to be rollable.
A bush that is internally fitted into the connecting hole and externally fitted to the rolling fulcrum shaft,
A breather circuit that communicates the differential mechanism chamber in which the differential mechanism of the wheel drive case is housed to the outside of the wheel drive case is provided.
The breather circuit is provided with a circuit unit for communicating the differential mechanism chamber and the connecting hole.
The bush is provided with a through hole that communicates the outside and the inside of the bush and communicates with the circuit portion.
An inner peripheral groove is provided on the inner peripheral surface of the bush.
An axle device in which the through hole and the inner peripheral groove are communicated with each other . The axle device according to any one of claims 1 to 5 , wherein the breather circuit has a function of supplying grease to the bush. A work vehicle including the axle device according to any one of claims 1 to 6 .

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