Multipurpose work vehicle

Abstract

To provide a multipurpose work vehicle capable of realizing more stable travel in a state where a work machine is attached thereto.SOLUTION: A multipurpose work vehicle includes: a travel device which includes a crawler structure and has a drive wheel arranged at a position of a vertex in a side view, a movable first driven wheel disposed on one side in the travel direction relative to the drive wheel, and an immovable second driven wheel disposed on the other side in the travel direction relative to the drive wheel; a power device which is disposed on the side of the second driven wheel relative to the drive wheel, and to which a drive source having an engine and a motor, and a battery are fixed; and a work machine which is arranged on the side of the first driven wheel relative to the drive wheel. The first driven wheel moves in a direction in which a distance between the second driven wheel and itself changes.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a multi-purpose work vehicle.

Background Art

[0002] There is a multi-purpose management work vehicle characterized in that a transport work platform that has a crawler structure running unit and covers the base of a lifting boom having a work platform at the tip of a rotatable support column and the upper part of the running vehicle body is integrally rotatably attached. (For example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the prior art, no matter what working machine is attached to the vehicle, there is room for improvement in achieving more stable running.

[0005] The present invention has been made in view of the above, and an object thereof is to provide a multi-purpose work vehicle capable of achieving more stable running with a working machine attached.

Means for Solving the Problems

[0006] In order to solve the above-described problems and achieve the object, a multi-purpose work vehicle (1) according to an embodiment has a crawler structure, and includes a drive wheel (22) disposed at the apex position in a side view, a movable first driven wheel (23) disposed on one side in the traveling direction with respect to the drive wheel (22), and a non-movable second driven wheel (24d) disposed on the other side in the traveling direction with respect to the drive wheel (22). The traveling device (2) has a power unit (31) disposed on the second driven wheel (24d) side with respect to the drive wheel (22), to which a drive source having an engine (315) and a motor (316) and a battery (314) are fixed, and a work implement (W) disposed on the first driven wheel (23) side with respect to the drive wheel (22). The first driven wheel (23) moves in a direction in which the distance from the second driven wheel (24d) changes.

Effect of the Invention

[0007] According to the work vehicle according to the embodiment, more stable traveling can be realized with the work implement attached.

Brief Description of the Drawings

[0008]

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BEST MODE FOR CARRYING OUT THE INVENTION

[0009] Hereinafter, embodiments of the management system disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments shown below.

[0010] First, the configuration of the multi-purpose work vehicle 1 according to the embodiment will be described with reference to FIGS. 1 to 5. FIGS. 1 and 2 are perspective views of the multi-purpose work vehicle 1 according to the embodiment. FIG. 3 is a side view of the multi-purpose work vehicle 1 according to the embodiment. FIGS. 4 and 5 are perspective views of the multi-purpose work vehicle 1 according to the embodiment. The multi-purpose work vehicle 1 in the present disclosure is an unmanned work vehicle that performs agricultural work in a field or the like.

[0011] In addition, the multi-purpose work vehicle 1 executes predetermined work while autonomously traveling in the field under the control of each part by a control system centered on a control device 311 described later. Further, the multi-purpose work vehicle 1 can be equipped with various types of work implements described later, and can switch between forward and reverse travel directions according to the type of work implement.

[0012] As shown in FIG. 1, the multi-purpose work vehicle 1 includes a traveling device 2 and a main body 3. The traveling device 2 is a crawler-type traveling part arranged at both ends in the vehicle width direction of the main body 3. The traveling device 2 includes a belt part 21, a drive wheel 22, a first driven wheel 23, and a plurality of second driven wheels 24a to 24d.

[0013] The belt part 21 is provided so as to cover the drive wheel 22, the first driven wheel 23, and the plurality of second driven wheels 24a to 24d. Further, the belt part 21 has a substantially triangular shape in side view, and a portion corresponding to the base of the triangle contacts the ground such as a field. The belt part 21 moves as the drive wheel 22, the first driven wheel 23, and the plurality of second driven wheels 24a to 24d rotate, thereby causing the multi-purpose work vehicle 1 to travel. The belt part 21 is made of an elastic resin material such as rubber, for example.

[0014] The drive wheel 22 is connected to a drive source (engine 315 and motor 316) described later and is driven by the power of the drive source. The first driven wheel 23 and the second driven wheels 24a to 24d are driven to rotate by the power transmitted from the rotation of the drive wheel 22 via the belt part 21.

[0015] Here, with reference to FIG. 3, the arrangement and operation of the traveling device 2 will be described in detail. In FIG. 3, for convenience, the illustration of the belt part 21 is omitted.

[0016] As shown in FIG. 3, the drive wheel 22 is arranged at the vertex position of the belt part 21 (see FIG. 1) that is triangular in side view. Further, the first driven wheel 23 and the second driven wheels 24a to 24d are arranged below (ground side) the drive wheel 22.

[0017] In the example shown in FIG. 3, the first driven wheel 23 is arranged on one side in the traveling direction with respect to the driving wheel 22. Specifically, the first driven wheel 23 is arranged on the working connection arm 33 side (i.e., the working machine side) with respect to the driving wheel 22. Further, the second driven wheels 24a to 24d are arranged on the power unit 31 side with respect to the first driven wheel 23. Among the second driven wheels 24a to 24d, the second driven wheels 24a to 24c are arranged directly below the driving wheel 22, and the second driven wheel 24d is arranged on the other side in the traveling direction (the power unit 31 side) with respect to the driving wheel 22.

[0018] Also, as shown in FIG. 3, the first driven wheel 23 is movable, and the second driven wheels 24a to 24d are immovable. Specifically, the first driven wheel 23 moves in a direction in which the distance from the second driven wheels 24a to 24d changes. More specifically, the first driven wheel 23 is connected to the damper 25 and moves by the expansion and contraction of the damper 25. Further, the second driven wheels 24a to 24d are fixedly arranged on a frame (not shown).

[0019] FIG. 3 shows the state in which the distance between the first driven wheel 23 and the second driven wheels 24a to 24d is the shortest (upper figure) and the state in which such distance is the longest (lower figure). As shown in FIG. 3, when the first driven wheel 23 moves, the height from the center of the driving wheel 22 to the ground contact surface changes. That is, the height of the triangular belt portion 21 shown in FIG. 1 changes. Specifically, when the first driven wheel 23 moves by a distance L toward the working connection arm 33 side, the height H1 becomes shorter than the height H2. In other words, the height of the belt portion 21 becomes shorter, and the ground contact surface becomes longer by the distance L.

[0020] As a result, for example, even when the force pulling the working machine side by the working machine connected to the working connection arm 33 becomes large, stable traveling is possible. Also, by arranging the power unit 31 and the working machine on opposite sides with respect to the driving wheel 22, a balanced vehicle layout without weight bias can be realized. That is, more stable traveling can be realized when the working machine of the multi-purpose work vehicle 1 is connected.

[0021] Returning to FIG. 1, the configuration of the main body 3 will be specifically described.

[0022] The main body 3 includes a power unit 31, a PTO (Power Take Off) shaft 32, a work connection arm 33, a transmission case 34, and a gear case 35. The power unit 31 is disposed on one side in the traveling direction with respect to the drive wheels 22, and the PTO (Power Take Off) shaft 32, the work connection arm 33, the transmission case 34, and the gear case 35 are disposed on the other side.

[0023] The power unit 31 is a device that generates various powers, and includes a control device 311, a BMS (Buttery Management System) 312, a fuel tank 313, a battery 314, an engine 315, a motor 316, and a radiator 317.

[0024] The PTO shaft 32 extends from the transmission case 34 to the side opposite to the power unit 31 (the side of the working machine) and is connected to the working machine, and is a member that transmits the power transmitted from the transmission case 34 to the working machine. The work connection arm 33 is a connecting portion for connecting the working machine, and is configured to be capable of lifting and lowering operations, and can lift and lower the working machine. The gear case 35 includes axles connected to the drive wheels 22 at both ends of the main body 3, respectively, and gears that transmit the power transmitted from the transmission case 34 to the axles. The transmission case 34 transmits the rotational power generated by the engine 315 and / or the motor 316 to the PTO shaft 32 and the gear case 35.

[0025] The control device 311 is a device on which a control board for controlling the engine 315, the BMS 312, and the motor 316 is mounted, and is disposed on the outermost side in the main body 3. Although not shown in the figure, an operation unit for controlling the multi-purpose work vehicle 1 may be provided on the cover surface of the control device 311. By such an operation unit, a person can manually operate the multi-purpose work vehicle 1.

[0026] The BMS 312 is arranged adjacent to the control device 311 on the outermost side of the main body 3 and is a device that manages the state of the battery 314. The fuel tank 313 is a tank that stores fuel to be supplied to the engine 315. The battery 314 supplies power to the motor 316. Also, the battery 314 can be charged by the power generated by the regeneration of the motor 316. The engine 315 generates power to be transmitted to the transmission case 34. The motor 316 generates power to be transmitted to the transmission case 34. The radiator 317 is arranged on the drive wheel 22 side with respect to the engine 315 and the motor 316 and cools the engine 315 and the motor 316.

[0027] Also, as shown in FIG. 5, a first pulley 315p (power transmission part) is connected to the engine 315, a second pulley 316p (power transmission part) is connected to the motor 316, and a third pulley 32p (power transmission part) is connected to the PTO shaft 32 leading to the transmission case 34. Further, the first pulley 315p, the second pulley 316p, and the third pulley 32p are connected by a belt 318. That is, the first pulley 315p, the second pulley 316p, and the third pulley 32p are arranged on the same plane and connected to each other. Thereby, the first pulley 315p and the second pulley 316p are rotated by the power of the engine 315 and the motor 316, and the third pulley 32p is driven to rotate by the rotation of the first pulley 315p and the second pulley 316p. As a result, when the PTO shaft 32 rotates, the power of the engine 315 and the motor 316 is transmitted to the transmission case 34. That is, since the combined force of the engine 315 and the motor 316 can be transmitted to the PTO shaft 32, it is possible to cope with cases where a large amount of power is required for work implements or traveling. When the PTO shaft 32 is not connected to a work implement, the power of the engine 315 may be used to generate regenerative power of the motor 316. That is, when the PTO shaft 32 is not connected to a work implement, the output of the engine 315 is maintained at the same output as when the PTO shaft 32 is connected to a work implement, and the motor 316 is rotated by the power of the engine 315 to generate regenerative power. Specifically, the motor 316 is rotated by the power of the engine 315 via the first pulley 315p and the second pulley 316p to generate regenerative power. Thereby, the engine efficiency in the multi-purpose work vehicle 1 can be increased.

[0028] Next, with reference to FIGS. 6 to 18, a configuration in which various work implements W are attached to the multi-purpose work vehicle 1 will be described.

[0029] Figs. 6 and 7 are diagrams showing an example in which a tillage and transport machine W1, which is a working machine W, is mounted. Figs. 8 and 9 are diagrams showing an example in which a transplanter W2, which is a working machine W, is mounted. Figs. 10 and 11 are diagrams showing an example in which a control machine W3, which is a working machine W, is mounted. Figs. 12 and 13 are diagrams showing an example in which an earth moving machine W4, which is a working machine W, is mounted. Figs. 14 and 15 are diagrams showing an example in which a harvester W5, which is a working machine W, is mounted. Note that the tillage and transport machine W1, the transplanter W2, the control machine W3, the earth moving machine W4, and the harvester W5 are all connected by a working connection arm 33.

[0030] The tillage and transport machine W1 shown in Figs. 6 and 7 is a working machine that tills a traveling path on which the multi-purpose work vehicle 1 travels. Further, the tillage and transport machine W1 is driven by power transmitted from the PTO shaft 32. Note that the tillage and transport machine W1 may be provided with, for example, an electric motor (not shown) and may preliminarily have a function of being driven by such an electric motor. The tillage and transport machine W1 is disposed on the side opposite to the second driven wheel 24d. That is, the tillage and transport machine W1 is disposed on the side opposite to the power unit 31 on the second driven wheel 24d side. Further, the multi-purpose work vehicle 1 with the tillage and transport machine W1 mounted thereon travels in a direction opposite to that of the tillage and transport machine W1. That is, the multi-purpose work vehicle 1 with the tillage and transport machine W1 mounted thereon travels in a direction with the side where the power unit 31 is disposed (the second driven wheel 24d side) as the front side and the second driven wheel 24d side as the front side. Further, the position of the first driven wheel 23 of the multi-purpose work vehicle 1 with the tillage and transport machine W1 mounted thereon is determined according to the lifting position of the tillage and transport machine W1. This point will be described with reference to Fig. 16.

[0031] FIG. 16 is a view showing the position of the first driven wheel 23 of the multi-purpose work vehicle 1 to which the tillage and transport machine W1 is attached. As shown in FIG. 16, when the tillage and transport machine W1 is in the raised state (non-working state), the first driven wheel 23 shortens the distance to the second driven wheel 24d (to the shortest distance), and when the tillage and transport machine W1 is in the lowered state (working state), the distance to the second driven wheel 24d is lengthened (to the longest distance). Thereby, in the working state, by lengthening the ground contact area of the belt portion 21, stable traveling can be realized without tipping over even by the force pulled rearward (toward the tillage and transport machine W1 side) by tillage. Further, during non-operation, since no force is generated by tillage, the ground contact area of the belt portion 21 can be shortened to improve the turning performance (make it easier to turn in a small radius). In FIGS. 6 and 7, the tillage and transport machine W1 is taken as an example, but the same applies even when a towing object, which is a heavy object, is arranged at the position of the tillage and transport machine W1.

[0032] Next, the transplanter W2 shown in FIGS. 8 and 9 is a working machine that automatically transplants seedlings onto the traveling path on which the multi-purpose work vehicle 1 travels. The transplanter W2 is also driven by the power transmitted from the PTO shaft 32. The transplanter W2 may be provided with, for example, an electric motor (not shown) and preliminarily have a function of being driven by such an electric motor. The transplanter W2 includes a planting part W2a, a feeding part W2b, and a seedling standby W2c. The planting part W2a plants the seedlings sent by the feeding part W2b in the field. The feeding part W2b has an inclined surface that slopes downward from the seedling standby W2c toward the planting part W2a, and feeds the seedlings placed in the seedling standby W2c to the planting part W2a via the inclined surface. The seedling standby W2c is a space for placing the seedlings. In FIG. 8, the seedling standby W2c is shown as a flat plate-like member, but it may be, for example, a box-shaped shape with an open upper part, a tank shape, or the like. The seedling standby W2c is arranged, for example, above the drive wheel 22, that is, at the central part of the multi-purpose work vehicle 1 when viewed from above. Thereby, it is possible to avoid the weight balance of the multi-purpose work vehicle 1 from being biased when the seedlings are placed in the seedling standby W2c.

[0033] In addition, the transplanting machine W2 is disposed on the side opposite to the second driven wheel 24d. That is, the transplanting machine W2 is disposed on the side opposite to the power unit 31 on the side of the second driven wheel 24d. The multi-purpose work vehicle 1 equipped with the transplanting machine W2 travels in the direction opposite to the transplanting machine W2. That is, the multi-purpose work vehicle 1 equipped with the transplanting machine W2 travels in a direction with the side where the power unit 31 is disposed (the side of the second driven wheel 24d) as the front side and the side of the second driven wheel 24d as the front side.

[0034] In addition, the first driven wheel 23 of the multi-purpose work vehicle 1 equipped with the transplanting machine W2 increases the distance from the second driven wheel 24d (to the longest distance) during the transplanting operation, and shortens the distance from the second driven wheel 24d (to the shortest distance) when not in the transplanting operation. Thereby, even if the weight on the side of the transplanting machine W2 increases while the preparatory seedlings pass through the feeding section W2b or while the seedlings are present in the planting section W2a, tipping can be avoided. Note that the distance between the first driven wheel 23 and the second driven wheel 24d, in other words, the height from the drive wheel 22 to the ground contact surface may be appropriately adjusted according to the planting depth of the planting section W2a.

[0035] Next, the control machine W3 shown in FIGS. 10 and 11 is a working machine that sprays chemicals for insecticide, bactericide, disinfection, and chemicals such as hormones around the traveling path on which the multi-purpose work vehicle 1 travels. In addition, the control machine W3 is driven by the power transmitted from the PTO shaft 32. Note that the control machine W3 may be provided with, for example, an electric motor (not shown) and may be preliminarily provided with a function of being driven by such an electric motor. The control machine W3 includes a chemical tank W3a and a spraying section W3b. The chemical tank W3a is a tank that stores chemicals and is disposed on the main body section 3 side with respect to the spraying section W3b. The spraying section W3b is a member that sprays the chemicals in the chemical tank. In the example shown in FIG. 10, a structure in which a plurality of rod-shaped members with spraying holes arranged in a U shape is shown. The spraying section W3b shown in FIG. 10 sprays the chemicals onto the ground directly below from the spraying holes of the rod-shaped member disposed parallel to the ground at the lower end, and sprays the chemicals outside the multi-purpose work vehicle 1 from the spraying holes of the rod-shaped members disposed perpendicular to the ground at both ends in the vehicle width direction of the multi-purpose work vehicle 1.

[0036] Further, the control machine W3 is disposed on the side opposite to the second driven wheel 24d. That is, the control machine W3 is disposed on the side opposite to the power unit 31 on the second driven wheel 24d side. The multi-purpose work vehicle 1 equipped with the control machine W3 travels in the direction of the control machine W3 side. That is, the multi-purpose work vehicle 1 equipped with the control machine W3 travels in a direction with the side where the power unit 31 is disposed (the second driven wheel 24d side) as the rear side and the first driven wheel 23 side as the front side. When the control machine W3 is in a shape for spraying chemicals rearward, the multi-purpose work vehicle 1 may travel in the direction opposite to the control machine W3.

[0037] Also, as shown in FIG. 17, the first driven wheel 23 of the multi-purpose work vehicle 1 equipped with the control machine W3 shortens the distance from the second driven wheel 24d (to the shortest distance) during chemical spraying, and when not during chemical spraying, lengthens the distance from the second driven wheel 24d (to the longest distance). FIG. 17 is a diagram showing the position of the first driven wheel 23 of the multi-purpose work vehicle 1 equipped with the control machine W3. That is, during chemical spraying, the vehicle height is increased to widen the spraying range, and when not during chemical spraying, the vehicle height is decreased to avoid contact with the spraying unit W3b etc. and ensure stability during turning.

[0038] Next, the soil piling machine W4 shown in FIGS. 12 and 13 is a working machine for cultivating the traveling road on which the multi-purpose work vehicle 1 travels. Further, the soil piling machine W4 is driven by the power transmitted from the PTO shaft 32. The soil piling machine W4 may be provided with, for example, an electric motor (not shown) and may preliminarily have a function of being driven by such an electric motor. Further, the soil piling machine W4 is arranged on the side opposite to the second driven wheel 24d. That is, the soil piling machine W4 is arranged on the side opposite to the power unit 31 on the side of the second driven wheel 24d. Further, the multi-purpose work vehicle 1 equipped with the soil piling machine W4 travels in the direction opposite to the soil piling machine W4. That is, the multi-purpose work vehicle 1 equipped with the soil piling machine W4 travels in a direction in which the side where the power unit 31 is arranged (the side of the second driven wheel 24d) is the front side and the side of the second driven wheel 24d is the front side. Further, the position of the first driven wheel 23 of the multi-purpose work vehicle 1 equipped with the soil piling machine W4 is determined according to the lifting position of the soil piling machine W4. Specifically, when the soil piling machine W4 is in the raised state (non-working state), the first driven wheel 23 shortens the distance from the second driven wheel 24d (to the shortest distance), and when the soil piling machine W4 is in the lowered state (working state), the distance from the second driven wheel 24d is increased (to the longest distance). Thereby, in the working state, by increasing the contact area of the belt portion 21 on the ground surface, stable traveling can be realized without tipping over even by the force pulled to the rear side (the side of the soil piling machine W4) by soil piling. Further, during non-operation, since no force is generated by soil piling, the contact area of the belt portion 21 on the ground surface can be shortened to improve the turning performance (it is easier to make a small turn).

[0039] Next, the harvester W5 shown in FIGS. 14 and 15 is a working machine that harvests the harvested crops planted on the traveling road on which the multi-purpose work vehicle 1 travels. Further, the harvester W5 is driven by the power transmitted from the PTO shaft 32. Note that the harvester W5 may be provided with an electric motor (not shown), for example, and may preliminarily have a function of being driven by such an electric motor. The harvester W5 includes a first conveyor section W5a, a second conveyor section W5b, and a storage section W5c. The first conveyor section W5a has a tip that contacts (or digs into) the ground and serves as a cutting section for cutting the harvested crops, and has an inclined surface that slopes upward from the cutting section at the tip toward the second conveyor section W5b, and a plurality of rollers are arranged side by side on such an inclined surface. That is, the cutting section is provided on the side opposite to the second driven wheel 24d (power unit 31). Each roller rotates by power from the PTO shaft 32 or the like, and conveys the harvested crops cut by the cutting section to the second conveyor section W5b. Further, by being composed of rollers, unnecessary soil or the like adhering to the harvested crops can be dropped onto the ground during transportation. The second conveyor section W5b has an inclined surface that slopes downward toward the storage section W5c, and such an inclined surface is formed in a belt shape. Thereby, the harvested crops conveyed from the first conveyor section W5a can be conveyed to the storage section W5c. Further, by being formed in a belt shape, it is possible to avoid the soil adhering to the harvested crops from directly falling onto the transmission case 34 or the like during transportation in the second conveyor section W5b. Note that the second conveyor section W5b may be a belt conveyor in which the belt is driven by power. The storage section W5c is a box-shaped member that stores the harvested crops conveyed from the second conveyor section W5b. The storage section W5c is configured to be detachable and can be replaced with an empty storage section W5c when it is full of harvested crops.

[0040] Further, in the harvester W5, the first conveyor section W5a is disposed on the side opposite to the second driven wheel 24d, and the storage section W5c is disposed on the side of the second driven wheel 24d. That is, the first conveyor section W5a of the harvester W5 is disposed on the side opposite to the power unit 31 which is on the side of the second driven wheel 24d. The multi-purpose work vehicle 1 with the harvester W5 mounted thereon travels in the direction of the harvester W5 (the first conveyor section W5a) side. That is, the multi-purpose work vehicle 1 with the harvester W5 mounted thereon travels in a direction with the side where the power unit 31 is disposed (the second driven wheel 24d side) as the rear side and the first driven wheel 23 side as the front side.

[0041] Also, as shown in FIG. 18, the first driven wheel 23 of the multi-purpose work vehicle 1 with the harvester W5 mounted thereon increases the distance from the second driven wheel 24d (to the longest distance) during the harvesting operation, that is, when the tip of the first conveyor section W5a touches the ground, and decreases the distance from the second driven wheel 24d (to the shortest distance) when not in the harvesting operation, that is, when the tip of the first conveyor section W5a is raised (when the first conveyor section W5a is parallel to the ground). FIG. 18 is a view showing the position of the first driven wheel 23 of the multi-purpose work vehicle 1 with the harvester W5 mounted thereon. That is, during the harvesting operation, by increasing the ground contact area of the belt section 21, stable traveling can be realized without tipping over even by the force of being pulled forward (the tip side of the first conveyor section W5a) during the transportation of the first conveyor section W5a. Further, during non-harvesting operations, by increasing the vehicle height, it is possible to avoid the tip of the first conveyor section W5a from contacting the harvested crop or the like.

[0042] The multi-purpose work vehicle 1 according to the above-described embodiment has a crawler structure, and includes a drive wheel 22 disposed at the apex position in a side view, a movable first driven wheel 23 disposed on one side in the traveling direction with respect to the drive wheel 22, and a non-movable second driven wheel 24d disposed on the other side in the traveling direction with respect to the drive wheel 22. The traveling device 2, a power device 31 disposed on the second driven wheel 24d side with respect to the drive wheel 22, to which a drive source having an engine 315 and a motor 316 and a battery 314 are fixed, and a work implement W disposed on the first driven wheel 23 side with respect to the drive wheel 22. The first driven wheel 23 moves in a direction in which the distance from the second driven wheel 24d changes. Thereby, more stable traveling can be realized in a state where the work implement is attached.

[0043] Further effects and modifications can be easily derived by those skilled in the art. For this reason, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Therefore, various changes can be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

Explanation of Signs

[0044] 1 Multi-purpose work vehicle 2 Traveling device 3 Body part 21 Belt part 22 Drive wheel 23 First driven wheel 24a~24d Second driven wheel 25 Damper 31 Power device 32 PTO shaft 32p Third pulley 33 Work connection arm 34 Transmission case 35 Gear case 311 Control device 313 Fuel tank 314 Battery 315 Engine 315p First pulley 316 Motor 316p Second Pulley 317 Radiator 318 Belt H1 Height H2 Height L Distance W Working Machine W1 Cultivation and Transportation Machine W2 Transplanter W2a Planting Unit W2b Feeding Unit W2c Seedling Storage W3 Weed Control Machine W3a Chemical Tank W3b Spraying Unit W4 Earth Moving Machine W5 Harvester W5a First Conveyor Unit W5b Second Conveyor Unit W5c Storage Unit

Claims

1. A crawler structure comprising a driving wheel disposed at the vertex position in side view, a movable first driven wheel disposed on one side of the driving wheel in the traveling direction, and a non-movable second driven wheel disposed on the other side of the driving wheel in the traveling direction; a traveling device having, a power unit disposed on the second driven wheel side with respect to the driving wheel, to which a drive source having an engine and a motor and a battery are fixed; a work implement disposed on the first driven wheel side with respect to the driving wheel; comprising, wherein the first driven wheel, moves in a direction in which the distance from the second driven wheel changes; a multi-purpose work vehicle.

2. The traveling device, when traveling straight, moves the first driven wheel in a direction in which the distance from the second driven wheel increases, and when turning, moves the first driven wheel in a direction in which the distance from the second driven wheel decreases. The multi-purpose work vehicle according to Claim 1.

3. The work implement, is a tillage vehicle or a towing implement, and is disposed on the side opposite to the power unit in the traveling direction, the traveling device, travels in a direction with the side where the power unit is disposed as the front side and the second driven wheel as the front side. The multi-purpose work vehicle according to Claim 1.

4. The work implement, is a harvesting machine having a cutting unit provided on the side opposite to the power unit in the traveling direction, the traveling device, travels in a direction with the side where the power unit is disposed as the rear side and the first driven wheel as the front side. The multi-purpose work vehicle according to Claim 1.

5. further comprising a PTO shaft for driving the work implement, wherein the power transmission parts of the engine, the motor, and the PTO shaft are located on the same plane. The multi-purpose work vehicle according to Claim 1.

6. When the PTO shaft is not connected to the work implement, maintain the output of the engine at the same output as when the PTO shaft is connected to the work implement, and rotate the motor by the power of the engine to generate regenerative power. The multi-purpose work vehicle according to Claim 5.

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