Work vehicle

Abstract

To provide a work vehicle which can travel on uneven ground, the work vehicle capable of performing the type of work that requires a drive source with a simple structure.SOLUTION: A work vehicle includes: a plurality of travel devices 2 located in front and rear in both right and left sides of a vehicle body 1; a plurality of travel drive devices 4 that drive the plurality of travel devices 2, respectively; a support mechanism A that supports the plurality of travel devices 2 to the vehicle body 1 in a manner that the travel devices 2 can ascend and descend separately from each other; and a power take-out part TO capable of taking out rotation power of the travel drive devices 4 to the outside of the vehicle body.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a work vehicle suitable for traveling on uneven ground such as uneven surfaces or mountainous areas. [Background technology]

[0002] Conventionally, the above-mentioned work vehicle has been configured such that four running wheels are supported on the vehicle body via a bending link mechanism in a support mechanism, and by changing the height of the running wheels relative to the vehicle body, the running wheels can rotate while following the ground contact even if the ground is uneven (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-111985 A Summary of the Invention [Problem to be solved by the invention]

[0004] With the above configuration, even when traveling on uneven ground such as uneven surfaces or mountainous areas (hereinafter simply referred to as uneven ground), it is possible to travel while maintaining the posture of the vehicle body in a predetermined posture, such as a horizontal posture, with multiple running wheels in contact with the ground.

[0005] Work carried out in mountainous areas and the like where this type of work vehicle is used includes, for example, fruit growing and harvesting work. When carrying out such work, not only is the harvested product transported by the work vehicle carried out, but also the work of spraying water and chemicals on the crops. Conventionally, when carrying out such spraying work, it was necessary to prepare a dedicated liquid spraying work machine with a drive source, which had disadvantages such as high costs and the cumbersome effort of transporting a large amount of equipment.

[0006] Therefore, there has been a demand for a work vehicle capable of traveling on rough ground that is capable of performing work that requires a drive source with a simple configuration. [Means for solving the problem]

[0007] The characteristic configuration of the work vehicle according to the present invention is a vehicle body, a plurality of travel devices located at the front and rear of both the left and right sides of the vehicle body, a plurality of travel drive devices that drive each of the plurality of travel devices, and a support mechanism that supports the plurality of travel devices on the vehicle body so that each of the plurality of travel devices can be raised and lowered. a towing support section provided separately from the vehicle body on each of the traveling devices that can be raised and lowered separately, the towing support section supporting the movable carriage so that the movable carriage can be towed; and a power take-off unit capable of taking off the rotational power of the traveling drive device to the outside of the vehicle body.

[0008] According to the present invention, since the support mechanism can raise and lower each of the multiple traveling devices, it is possible to raise one or more of the multiple traveling devices above the traveling surface. Also, since each of the multiple traveling devices can be driven by the traveling drive device, the raised traveling devices can also be rotated by the traveling drive device. Furthermore, by providing a power take-off unit, it is possible to take out power from the traveling drive device that is raised above the traveling surface to the outside of the vehicle body.

[0009] As a result, even when work requiring a power source is required, the traveling drive device can be utilized, eliminating the hassle of having to prepare a dedicated work machine with a power source, and the work can be performed with a simple configuration.

[0010] Therefore, it has become possible to perform work that requires a drive source with a simple configuration in a work vehicle that can travel on rough ground. Also, since the rotational power of the travel drive devices for the front, rear, left and right of the vehicle body can be controlled separately, different powers can be taken out simultaneously from one vehicle. Also, by controlling the travel drive devices, it is possible to realize a variety of power take-off methods according to the application, such as taking out rotational power with infinite rotation, taking out rotational power by rotating by a certain angle, or taking out rotational power by rotating with an arbitrary torque.

[0011] In the present invention, it is preferable that the traveling device includes a swivel cylinder, and the swivel cylinder swings the traction support part left and right.

[0012]

[0013] In the present invention, it is preferable that the support mechanism is provided with a bending link mechanism, the bending link mechanism is provided with a first link having one end supported so as to be swingable around a horizontal axis relative to the vehicle body, and a second link having one end supported on the other end of the first link so as to be swingable around the horizontal axis, the running device is supported on the other end of the second link, and an auxiliary wheel is supported at the connection point between the first link and the second link.

[0014] With this configuration, the support mechanism can stably support the vehicle body with a wide contact width in the fore-and-aft direction using the running gear and the auxiliary wheels, and by changing the swing posture of the first link relative to the vehicle body, the running gear and the auxiliary wheels can be raised and lowered relative to the vehicle body. Furthermore, by fixing the swinging attitude of the first link relative to the vehicle body and changing the swinging attitude of the second link relative to the first link, the traveling device can be raised and lowered with the auxiliary wheels fixed in position.

[0015] As a result, it is possible to lift the running gear with the auxiliary wheels on the ground, and power can be taken from the running drive gear with the vehicle body stably supported on the ground using the auxiliary wheels.

[0016] In the present invention, it is preferable that the power take-off section includes a mounting portion to which a power take-off attachment can be attached while being positioned on a lateral side of the traveling device.

[0017] According to this configuration, it is possible to drive the external working device via the power take-off attachment attached to the mounting portion, without requiring troublesome work such as detaching the traveling device from the support mechanism. [Brief description of the drawings]

[0018] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 2 is an overall side view of the movable dolly being towed; [Figure 8] FIG. 11 is a plan view of a support mechanism according to another embodiment. [Figure 9] FIG. 2 is an overall side view of the movable dolly being towed; [Figure 10] FIG. 2 is a plan view of the traction support. [Figure 11] FIG. 2 is a plan view of the traction support. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] An embodiment of the present invention will be described with reference to the drawings. In the following description, the direction of the arrow FW shown in the drawings is defined as "forward", the direction of the arrow BK is defined as "backward", the direction of the arrow RH is defined as "right", the direction of the arrow LH is defined as "left", the direction of the arrow UP is defined as "up", and the direction of the arrow DW is defined as "down".

[0020] [Reference embodiment] As shown in Figures 1 and 2, the work vehicle is equipped with a vehicle body 1 which is approximately rectangular in plan view and supports the entire vehicle, a number of running wheels 2 which serve as running devices supporting the vehicle body 1, a number of auxiliary wheels 3 provided corresponding to each of the multiple running wheels 2, a support mechanism A which supports the multiple running wheels 2 so that their position can be changed relative to the vehicle body 1, and a number of hydraulic motors 4 which serve as running drive devices which drive each of the multiple running wheels 2.

[0021] The traveling wheels 2 are located at the front and rear on both the left and right sides of the vehicle body 1. In this embodiment, the work vehicle is equipped with four traveling wheels 2, located at the left front, right front, left rear, and right rear. It also has four support mechanisms A, located at the left front, right front, left rear, and right rear. The support mechanisms A include a bending link mechanism 5 and a plurality of hydraulic cylinders 6, 7 that can individually change the position of the bending link mechanism 5.

[0022] A flat loading section 8 capable of loading luggage is provided on the upper portion of the vehicle body 1. For example, luggage such as containers for storing harvested products can be loaded and supported on the loading section 8.

[0023] The vehicle body 1 is provided below the loading section 8 with a hydraulic supply source 9 that sends hydraulic oil toward the hydraulic cylinders 6, 7 and the hydraulic motor 4, a valve mechanism 10 that adjusts the supply state of hydraulic oil from the hydraulic supply source 9, and an ECU (Electronic Control Unit) 11 that controls the operation of the valve mechanism 10. The hydraulic supply source 9 has a hydraulic pump driven by the engine. The ECU 11 has a microcomputer and is capable of executing various controls according to a control program. The valve mechanism 10 has a plurality of hydraulic control valves 13 that supply and discharge hydraulic oil or adjust the flow rate. The hydraulic control valves 13 and the ECU 11 constitute a control device C.

[0024] [Support mechanism] As described above, the support mechanism A includes the bending link mechanism 5 and the multiple hydraulic cylinders 6, 7. As shown in Fig. 3 and Fig. 4, the bending link mechanism 5 includes a base end portion 14 supported by the vehicle body 1, a first link 15 having an upper end portion supported on a lower portion of the base end portion 14 so as to be rotatable about a horizontal axis X1, and a second link 16 having one end portion supported on a lower end portion of the first link 15 so as to be rotatable about a horizontal axis X2 and having the running wheel 2 supported on the other end portion.

[0025] A support bracket 17 supporting the traveling wheel 2 is supported by a boss portion 18 provided at the swing side end of the second link 16 so as to be swingable around the vertical axis Y. A hydraulic cylinder 20 for swing operation (hereinafter referred to as a swing cylinder) is provided between a bracket 19 on one end side of the second link 16 and an arm portion 17a provided on the support bracket 17.

[0026] A plurality of hydraulic cylinders 6, 7 capable of individually changing the posture of each of the four bending link mechanisms 5 are provided corresponding to the four bending link mechanisms 5. That is, a first hydraulic cylinder 6 capable of changing the swing posture of the first link 15 relative to the vehicle body 1, and a second hydraulic cylinder 7 capable of changing the swing posture of the second link 16 relative to the first link 15 are provided.

[0027] When the first hydraulic cylinder 6 is extended or retracted with the second hydraulic cylinder 7 stopped, the first link 15, the second link 16, and the traveling wheel 2 swing together around the horizontal axis X1 of the pivot connection point with respect to the base end 14 while maintaining a constant relative posture. When the second hydraulic cylinder 7 is extended or retracted with the first hydraulic cylinder 6 stopped, the second link 16 and the traveling wheel 2 swing together around the horizontal axis X2 of the connection point between the first link 15 and the second link 16 while maintaining a constant posture of the first link 15.

[0028] Auxiliary wheels 3 are rotatably supported at the intermediate bent portions of each of the four bent link mechanisms 5. The auxiliary wheels 3 are configured with wheels having approximately the same outer diameter as the running wheels 2. A support shaft that pivotally connects the first link 15 and the second link 16 is extended so as to protrude outward in the vehicle body width direction, and the auxiliary wheels 3 are rotatably supported at the extended protruding portion of the support shaft.

[0029] By operating the turning cylinder 20, the traveling wheel 2 can be turned around the vertical axis Y relative to the articulating link mechanism 5, thereby enabling the vehicle to be turned.

[0030] The flow rate of the hydraulic oil is adjusted by the hydraulic control valve 13 corresponding to each hydraulic motor 4, so that the rotation speed of each hydraulic motor 4, that is, the rotation speed of each traveling wheel 2, can be changed individually.

[0031] [Sensor] This work vehicle is equipped with various sensors. 5, a head side pressure sensor S1 and a cap side pressure sensor S2 are provided for each of the four second hydraulic cylinders 7. The head side pressure sensor S1 detects the hydraulic pressure in the head side chamber of the second hydraulic cylinder 7. The cap side pressure sensor S2 detects the hydraulic pressure in the cap side chamber of the second hydraulic cylinder 7.

[0032] A plurality of stroke sensors S3 capable of detecting the amount of extension / retraction operation are provided for each of the four first hydraulic cylinders 6 and the four second hydraulic cylinders 7. The amount of extension / retraction operation of each hydraulic cylinder 6, 7 is a detection value corresponding to the swing position of the first link 15 and the second link 16 that are the objects of operation.

[0033] The vehicle body 1 is provided with a tilt sensor S4 that detects the tilt state of the vehicle body. The tilt sensor S4 is configured using an Inertial Measurement Unit (IMU) that is a well-known configuration. The IMU has a three-axis acceleration sensor and a gyro sensor, and can detect the change in the attitude of the vehicle body 1, specifically, the tilt in the front-rear and left-right directions.

[0034] A rotation sensor S5 is provided near the traveling wheels 2 to detect the rotation speed of the traveling wheels 2 driven by the hydraulic motor 4. Based on the rotation speed of the traveling wheels 2 detected by the rotation sensor S5, the supply of hydraulic oil to the hydraulic motor 4 is controlled so that the rotation speed of the traveling wheels 2 becomes a target value. A pressure sensor S6 is provided to detect the pressure of the hydraulic oil supplied to the hydraulic motor 4. Based on the pressure of the hydraulic oil detected by the pressure sensor S6, the supply (pressure) of hydraulic oil to the hydraulic motor 4 is controlled so that the drive torque of the traveling wheels 2 becomes a target value. A stroke sensor S7 capable of detecting the extension / retraction operation amount is provided for each of the four swing cylinders 20.

[0035] [ECU] The ECU 11 includes a posture control unit 100 and a driving control unit 101. When the vehicle is traveling with the four traveling wheels 2 in contact with the ground, the driving control unit 101 controls the operation of the hydraulic motor 4 for each of the four traveling wheels 2 so that the rotation speed of the traveling wheels 2 detected by the rotation sensor S5 becomes a target speed and the drive torque detected by the pressure sensor S6 becomes a target value.

[0036] When the vehicle body is moving and traveling, the attitude control unit 100 executes horizontal control for controlling the operation of the support mechanism A so that the vehicle body 1 is in a horizontal attitude based on the detection information of the inclination sensor S4.

[0037] In horizontal control, the posture control unit 100 controls the operation of the four first hydraulic cylinders 6 and the four second hydraulic cylinders 7 based on the detection information of the inclination sensor S4 so that the inclination angles in the forward / backward direction and the left / right direction from the horizontal posture of the vehicle body 1 become values ​​corresponding to the horizontal posture.

[0038] [Traction support part] 1 and 2, a towing support part 22 that supports the movable dolly ID so that it can be towed is provided in the center of the left and right direction on both the front and rear sides of the vehicle body 1. The tip of a connecting arm 23 extended from the movable dolly ID is connected to the towing support part 22, so that the movable dolly ID can be towed and pulled as the work vehicle moves and travels.

[0039] The towing support part 22 is fixed to an end of a support part 24 extended from the vehicle body 1, and is formed in a circular ring shape in a plan view. A hook member 25 that engages with the towing support part 22 is provided at the tip of a connecting arm 23 of the movable dolly ID. Therefore, the connecting arm 23 is connected to the towing support part 22 so as to be swingable in the vertical and horizontal directions. The connecting arm 23 is connected to the movable dolly ID so as to be swingable in the vertical and horizontal directions. The movable dolly ID is towed by the work vehicle while following the ground and smoothly turning.

[0040] [Power take-off section] The vehicle is provided with a power take-off unit TO capable of taking off the rotational power of the hydraulic motor 4 to the outside of the vehicle body. That is, as shown in Figures 2 and 3, the power take-off unit TO is provided with a mounting portion 27 on the side of any one of the four running wheels 2, more specifically, coaxially with the drive shaft of the running wheel 2, to which a power relay device 26 as an attachment for taking off power can be attached.

[0041] A power transmission shaft 28 that is rotationally driven by the hydraulic motor 4 is provided on the mounting portion 27 in a state of protruding laterally. The power transmission shaft 28 is configured, for example, as a splined shaft or a hexagonal shaft, into which an inserted driven shaft fits to transmit torque, or into a shape that rotates integrally with the driven shaft via a connecting pin that penetrates radially. In short, any configuration that allows the transmission of rotational power to the driven shaft will suffice.

[0042] When driving the external working device GS using the attached portion 27, first, as shown in Fig. 6, the posture of the articulated link mechanism 5 is adjusted so that the traveling wheel 2 equipped with the attached portion 27 is lifted off the ground. At this time, the grounding posture of the entire work vehicle is stabilized by grounding the auxiliary wheel 3 corresponding to the traveling wheel 2. It is also possible to support the work vehicle on the ground by the remaining three traveling wheels 2 without grounding the auxiliary wheel 3.

[0043] 3, the connecting portion 26A of the power relay device 26 is connected to the mounting portion 27. The power relay device 26 is configured to transmit rotational power to a power input portion 29 of the external working device GS. When the hydraulic motor 4 is driven with the power relay device 26 attached, the power of the hydraulic motor 4 is transmitted to the external working device GS via the power relay device 26, and work is performed. Various working devices can be used as the external working device GS. For example, there is a sprinkler pump that draws up water and sprays it on crops.

[0044] [Embodiment] In the above-described reference embodiment, the traction support part 22 is provided on the vehicle body 1, but instead of this configuration, the traction support part 22 may be provided on the bending link mechanism 5. As shown in Fig. 9, a tip end of a connecting arm 23 extended from the movable dolly ID is integrally connected to a support bracket 17 of any one of the four traveling wheels 2. A rear end of the connecting arm 23 is connected to the movable dolly ID so as to be swingable in the up-down and left-right directions. In this configuration, the movable carriage ID is pulled with the target traveling wheel 2 raised, as shown in Fig. 9. When the turning cylinder is operated, the connecting arm 23 swings left and right via the support bracket 17, as shown in Fig. 10 and Fig. 11, so that the movable carriage ID can be pulled so as to avoid, for example, protrusions and recesses on the ground. [Another embodiment] (1) In the above embodiment, the power take-off unit TO is configured to include a mounting portion 27 on the side of the running wheel 2 to which a power take-off attachment can be attached, but instead of this configuration, as shown in Fig. 8, the running wheel 2 may be removed from the support mechanism A, and the wheel mounting portion 30 after the running wheel 2 is removed may be used as the power take-off unit TO, and a power take-off attachment may be connected to the wheel mounting portion 30 to take off power. Also, the power take-off attachment may be connected to a position other than the drive shaft of the running wheel 2 via a gear or the like.

[0045] (2) In the above embodiment, the power take-off unit (mounting portion 27) can be provided for any one of the four running wheels 2, but it is also possible to provide a power take-off unit for two or more running wheels 2.

[0046]

[0047]

[0048] ( 3 In the above embodiment, the traveling drive device is configured with a hydraulic motor 4, but an electric motor may be used instead of the hydraulic motor 4, and the power of the engine may be transmitted via a transmission mechanism provided separately for each traveling wheel 2.

[0049] ( 4 In the above-described conventional configuration, the support mechanism A is configured to include a bending link mechanism 5 and hydraulic cylinders 6, 7. However, instead of this configuration, a hydraulic motor may be provided at the fulcrum of the swinging of the bending link mechanism 5, and the posture of the bending link mechanism 5 may be changed by the hydraulic motor.

[0050] ( 5) In the above embodiment, the support mechanism A is provided with a bending link mechanism 5, but instead of this configuration, for example, a robot arm that can bend in any direction may be used to support the running wheels 2. In short, any configuration may be used as long as it supports each of the running wheels 2 so that their height position relative to the vehicle body 1 can be freely changed and supports the vehicle body 1 so that its posture can be maintained, and the configuration of the support mechanism A can be modified in various ways. [Industrial Applicability]

[0051] The present invention can be applied to a work vehicle suitable for traveling on rough ground. [Explanation of symbols]

[0052] 1 Vehicle body 2 Running wheels 3 Training wheels 4. Travelling drive unit 5. Articulated link mechanism 15 First Link 16 Second Link 20 Swivel cylinder 22 Traction support 26 Attachment 27 Mounting part A Support mechanism ID mobile trolley TO Power takeoff X1 First horizontal axis center

Claims

1. A vehicle body, A plurality of traveling devices located at the front and rear of each of the left and right sides of the vehicle body; A plurality of travel drive devices each for driving the plurality of travel devices separately; a support mechanism that supports the plurality of traveling devices on the vehicle body so that each traveling device can be raised and lowered separately; The traveling devices, which can be raised and lowered separately, a towing support section provided separately from the vehicle body and configured to support the movable carriage so as to be towable; and a power take-off section capable of taking out the rotational power of the traveling drive device to the outside of the vehicle body.

2. The traveling device includes a turning cylinder, 2. The work vehicle according to claim 1, wherein the swivel cylinder swings the towing support part left and right.

3. The support mechanism is provided with an articulated link mechanism, The bending link mechanism includes a first link having one end supported to be swingable about a horizontal axis with respect to the vehicle body, and a second link having one end supported to be swingable about the horizontal axis on the other end of the first link, 3. The work vehicle according to claim 1, wherein the traveling device is supported on the other end of the second link, and an auxiliary wheel is supported at a connection point between the first link and the second link.

4. 4. The work vehicle according to claim 1, wherein the power take-off section is provided with a mounting section to which a power take-off attachment can be attached while being positioned on a lateral side of the traveling device.

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