JP7224279B2 - work vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle height adjustable work vehicle.

An example of the work vehicle as described above is disclosed in Patent Document 1. The work vehicle of Patent Document 1 is provided with a plurality of hydraulically driven traveling devices positioned on both left and right sides of a main body, and legs for supporting the traveling devices. Separately, a bending link mechanism is provided to be vertically supported by the main body. One end of the bending link mechanism is supported by the main body, and wheels for running are attached to the other end.
By swinging the support arm up and down with respect to the main body, the position of the wheels with respect to the main body is changed, and the vehicle height suitable for the work site and working conditions is set.

JP 2018-103681 A

However, in the technique of Patent Document 1, each of the legs that support the traveling device is provided with a bending link mechanism, so there is room for improvement in terms of cost reduction, structural simplification, and weight reduction.
SUMMARY OF THE INVENTION An object of the present invention is to realize a vehicle height adjustment mechanism for a work vehicle with a low cost and a simple configuration.

A work vehicle according to an aspect of the present invention includes a main body, a plurality of wheel support mechanisms provided in the main body, and wheels for traveling supported under each of the wheel support mechanisms, The wheel support mechanism includes a main body side portion attached to the main body portion and arranged to extend downward from the main body portion; a wheel support portion slidably supported by the main body side portion; and a fixing portion capable of fixing and unlocking the wheel support portion to the main body side portion; and a support portion connected to the connection portion. A drive motor for driving the wheel is supported on the inner portion of the support portion in the vehicle width direction. , the wheel is supported on the outer side of the supporting portion in the machine body width direction .

According to the above configuration, in the wheel support mechanism, when the wheel support portion (wheel) is slid upward along the extension direction of the main body side portion and fixed to the main body side portion by the fixing portion, the vehicle height is reduced. state is obtained. When the wheel support portion (wheel) is slid downward along the extending direction of the main body side portion and fixed to the main body side portion by the fixing portion, a high vehicle height is obtained.
As a result, the vehicle height adjustment mechanism can be realized at low cost, and the vehicle height adjustment mechanism can be realized with a structure that is simplified and reduced in weight.

In the present invention, the main body side portion extends downward in the vertical direction from the main body portion, and the wheel support portion is supported by the main body side portion so as to be slidable in the vertical direction. preferred.

In the technique of Patent Document 1 described above, the wheels are supported at the tip of the bending link mechanism that bends in the front-rear direction. When the vehicle height is high, the wheels approach the main body in the longitudinal direction, shortening the wheelbase.

On the other hand, according to the above configuration, the position of the wheel support portion (wheel) changes linearly along the vertical direction. . As a result, even if the vehicle height of the work vehicle is changed in accordance with the work site and work conditions, changes in the wheelbase can be suppressed, and changes in running characteristics can be suppressed.

In the present invention, at least one of the main body side portion and the wheel support portion is configured in a pipe shape, and one of the main body side portion and the wheel support portion having a pipe shape is provided with the main body side portion and the wheel support portion. It is preferable that the wheel support portion is supported by the main body side portion so as to be slidable along the extending direction of the main body side portion by inserting the other side portion.

According to the above configuration, in the wheel support mechanism, the other of the main body side portion and the wheel support portion is inserted into the pipe-shaped one of the main body side portion and the wheel support portion, thereby facilitating the sliding structure of the wheel support portion. This is advantageous in terms of structural simplification.

In the present invention, one of the body side portion and the wheel support portion is configured in the shape of a square pipe, the other of the body side portion and the wheel support portion is configured in the shape of a round pipe, and the body side portion and the wheel support portion are configured in the shape of a round pipe. By inserting the other of the main body side portion and the round pipe-shaped wheel support portion into one of the square pipe-shaped wheel support portions, the wheel support portion slides along the extending direction of the main body side portion. It is preferable that it is supported by the side portion of the main body as much as possible.

According to the above configuration, in the wheel support mechanism, the square pipe-shaped one of the main body side portion and the wheel support portion is inserted into the other round pipe-shaped portion of the main body side portion and the wheel support portion. A slide structure is obtained.

According to the above configuration, the contact area between the inner surface of the square pipe and the outer surface of the round pipe is smaller than the configuration in which the round pipe is inserted into the round pipe. A gap is created between the inner surface and the outer surface of the round pipe.
As a result, even if soil or mud enters the inside of the square pipe, it is difficult for the soil or mud to get caught between the inner surface of the square pipe and the outer surface of the round pipe due to the aforementioned small contact area. Due to the above-mentioned gaps, dirt and mud are easily discharged.

In the present invention, the main body side portion is supported by the main body portion so as to be capable of swinging about a steering shaft center along a direction in which the main body side portion extends, and the main body side portion is supported by the main body portion relative to the steering shaft. It is preferable that a steering actuator that can be swung around the core is provided.

According to the above configuration, in the wheel support mechanism, the wheel support portion is fixed to the main body side portion by the fixing portion. Since the portion (wheel) is swung integrally with the side portion of the main body, the direction of the work vehicle can be changed without difficulty.

In the present invention, it is preferable that a drive motor for driving the wheels is provided in the wheel support portion.

According to the above configuration, in the wheel support mechanism, the wheels and the drive motor are arranged close to each other. This is advantageous in terms of simplification of the structure for driving the wheels by the drive motor, because the positional relationship between the two remains unchanged.

In the present invention, it is preferable that the fender is fixedly or detachably attached to the wheel support portion so as to be arranged above the wheel.

According to the above configuration, in the wheel support mechanism, even if the wheel support portion is slid along the extending direction of the main body side portion, the positional relationship between the wheel and the fender does not change, so the function of the fender is stably exhibited. will be
If the fender is removably attached to the wheel support, the fender can be removed from the wheel support when the fender is not needed.

In the present invention, it is preferable that the fixing portion can fix and release the wheel support portion to and from the main body side portion at an arbitrary position or a plurality of positions along the extension direction of the main body side portion.

According to the above configuration, a vehicle height adjustment mechanism that can be adjusted to an arbitrary vehicle height or a plurality of vehicle heights can be realized at low cost. , a vehicle height adjustment mechanism can be realized.

In the present invention, it is preferable that the main body side portion is detachable from the main body portion.

According to the above configuration, in the vehicle height adjustment mechanism, the main body side portion can be detachably attached to the main body portion, so that the main body side portion can be replaced with a different length to easily adjust the vehicle height of the working vehicle. be able to.

It is a right side view of a work vehicle. 1 is a plan view of a work vehicle; FIG. It is a front view of a right front wheel support mechanism. It is an exploded perspective view of the main body side portion of the wheel support mechanism. FIG. 4 is a cross-sectional view showing a fixed state between a connection portion of the wheel support mechanism on the main body side and a connection portion of the wheel support portion; It is a perspective view of the wheel support part of a wheel support mechanism.

(Overall configuration of working vehicle)
1 to 6 show a work vehicle according to this embodiment, where F indicates the forward direction, B indicates the rearward direction, U indicates the upward direction, D indicates the downward direction, and R indicates the downward direction. The right direction is indicated, and L indicates the left direction.
In this embodiment, an example in which the present invention is applied to a work vehicle that runs autonomously based on GPS and travels by wireless control will be described, but the subject of application of the present invention is not limited to this.

As shown in FIGS. 1 and 2, the work vehicle includes a main body 1, four wheel support mechanisms 2 provided on the right and left sides of the front and rear parts of the main body 1, and wheel support mechanisms 2 are provided with four running wheels 3 supported on the lower part of each of them.

(Construction of main body)
As shown in FIGS. 1, 2, and 3, in the main body 1, upper and lower front frames 4 along the left-right direction, upper and lower rear frames 5 along the left-right direction, and upper and lower frames 5 along the front-rear direction. and lower right lateral frame 6, and upper and lower left lateral frames 6 along the front-rear direction.

The upper front frame 4, the rear frame 5, and the right and left lateral frames 6 are connected in a rectangular frame shape in plan view, and the lower front frame 4, the rear frame 5, and the right and left lateral frames 6 are connected. , are connected in a rectangular frame shape in a plan view. The upper frame-shaped structure and the lower frame-shaped structure configured as described above are connected by 7 to four vertical frames along the vertical direction.

A support frame 8 is connected to the lower right and left lateral frames 6 , and a hydraulic supply unit 9 is supported by the support frame 8 . The hydraulic supply unit 9 is provided with an engine (not shown), a hydraulic pump (not shown) driven by the engine, and the like.

A control valve assembly 10 containing a plurality of electromagnetically operated control valves (not shown) is supported by upper right and left lateral frames 6 . A control unit 11 provided with a CPU (not shown), various sensors (not shown), a receiver (not shown), etc. is supported by the control valve unit 10 .
Front and rear upper frames 12 are connected to the upper front frame 4 and rear frame 5 so as to cover the upper sides of the control valve section 10 and the control section 11 .

(Main body side part in wheel support mechanism)
As shown in FIGS. 1, 2, and 3, the wheel support mechanism 2 is provided with a body side portion 13, a wheel support portion 14, and a fixing pin 15 (corresponding to a fixing portion).

As shown in FIGS. 1 to 4, the body side portion 13 is provided with a square pipe-shaped base portion 16, and the base portion 16 has connecting holes 16a at its upper and lower portions. Upper and lower boss portions 17 are connected to the base portion 16 and arm portions 18 are connected to the base portion 16 .

A connecting portion 19 configured in a round pipe shape is provided in the main body side portion 13, two connecting holes 19a are opened in the upper portion of the connecting portion 19, and six fixing holes are provided in the lower portion of the connecting portion 19. 19b is open.

The connecting portion 19 is inserted into the base portion 16 from above, and the connecting pin 20 is inserted through the connecting hole 16a of the base portion 16 and the connecting hole 19a of the connecting portion 19, thereby connecting the base portion 16 and the connecting portion 19. It is
As described above, the main body side portion 13 is provided with the base portion 16, the boss portion 17, the arm portion 18, the connecting portion 19, the connecting pin 20, and the like.

As shown in FIGS. 1, 2, and 3, channel-shaped fulcrum portions 21 are connected to the front and rear portions of the upper right and left horizontal frames 6 in a front view, and the lower right and left horizontal frames 6 are connected to the fulcrum portions 21 . A channel-shaped fulcrum portion 21 is connected to the front portion and the rear portion when viewed from the front.

A boss portion 17 of the base portion 16 is supported by the fulcrum portion 21 so as to be swingable around the steering axis P1 along the vertical direction (extending direction of the main body side portion 13). A bracket 22 is connected to the upper right and left lateral frames 6 , and a double acting hydraulic cylinder 23 (corresponding to a steering actuator) is connected across the arm portion 18 and the bracket 22 .

As described above, the main body side portion 13 (the base portion 16 and the connecting portion 19) is attached to the main body portion 1 and extends downward from the main body portion 1 along the vertical direction (the extending direction of the main body side portion 13). state.

The body side portion 13 (the base portion 16 and the connection portion 19) is supported by the body portion 1 so as to be swingable around the steering axis P1 along the vertical direction. 16 and the connecting portion 19) are swung with respect to the main body portion 1 around the steering axis P1.

(Wheel Support Part in Wheel Support Mechanism)
As shown in FIGS. 1, 3, and 6, the wheel support portion 14 is provided with a connecting portion 24 having a rectangular pipe shape, and the connecting portion 24 is provided with two fixing holes 24a. A boss portion 25 is connected to a lower horizontal portion of the connecting portion 24 , and an angle-shaped support portion 26 in front view is connected to the lower portion of the boss portion 25 .

In the wheel support portion 14, the wheel 3 is rotatably supported on a support portion 26 so as to be positioned below the lower portion of the connection portion 24, and a drive motor 27 of the hydraulic motor type for driving the wheel 3 is supported. It is connected to the portion of the portion 26 opposite the wheel 3 . A fender 28 formed by bending a plate material is connected to the lower portion of the connecting portion 24 so as to be arranged above the wheel 3 .

As described above, the wheel support portion 14 is provided with the connection portion 24 , the boss portion 25 , the support portion 26 , and the like, and the wheel 3 is supported by the wheel support portion 14 .
A drive motor 27 for driving the wheels 3 is provided on the wheel support portion 14 , and a fender 28 is fixed to the wheel support portion 14 so as to be arranged above the wheels 3 .

(Connection between Body Side Part and Wheel Support Part in Wheel Support Mechanism)
In the body side portion 13 (see FIG. 4) and the wheel support portion 14 (see FIG. 6), as shown in FIGS. By inserting the round pipe-shaped connection portion 19 of 13, the wheel support portion 14 (connection portion 24) is extended to the main body side portion 13 (connection portion 19) in the vertical direction (extending direction of the main body side portion 13). slidably supported.

By inserting the fixing pin 15 across the two fixing holes 19b of the body side portion 13 (connection portion 19) and the fixing hole 24a of the wheel support portion 14 (connection portion 24), the wheel support portion 14 is (Connecting portion 24) is fixed to body side portion 13 (connecting portion 19) to set the vehicle height of the working vehicle (body portion 1).

By removing the fixing pin 15, the wheel support portion 14 (connection portion 24) can slide along the main body side portion 13 (connection portion 19) in the vertical direction (extending direction of the main body side portion 13).
By inserting the fixing pin 15 across the other two fixing holes 19b of the main body side portion 13 (connection portion 19) and the fixing hole 24a of the wheel support portion 14 (connection portion 24), the wheel support is performed. The portion 14 (connection portion 24) is fixed to the main body side portion 13 (connection portion 19) to change the vehicle height of the work vehicle (main body portion 1).

When the work vehicle travels on a slope such as a slope along a contour line, the wheel support portions 14 (connection portions 24 ) can be fixed to different positions of the main body side portion 13 (connecting portion 19). As a result, the heights of the right and left portions of the work vehicle (main body 1) are different, and the work vehicle can travel along contour lines while maintaining the main body 1 horizontally.

When greatly changing the vehicle height of the work vehicle (body portion 1), as shown in FIG. The base portion 16 and the connection portion 19 may be connected by inserting the portion 19 into the base portion 16 and inserting the connection pin 20 across the connection hole 16a of the base portion 16 and the connection hole 19a of the connection portion 19 .

As described above, the connection portion 19 can be attached to and detached from the base portion 16 at the main body side portion 13 , so that the main body side portion 13 (connection portion 19 ) can be attached to and detached from the main body portion 1 .
Even if the base portion 16 remains in the main body portion 1 at the main body side portion 13, the main body side portion 13 is replaced by replacing the connecting portion 19 with a connecting portion 19 having a different length.

(Work vehicle travels)
As shown in FIGS. 1 and 2, hydraulic oil from the hydraulic supply unit 9 is supplied to the four drive motors 27 through the control valves of the control valve unit 10, and the drive motors 27 move the wheels 3 forward and backward. driven in the opposite direction.

Hydraulic oil from the hydraulic supply unit 9 is supplied to the hydraulic cylinder 23 via the control valve of the control valve unit 10, and the expansion and contraction of the hydraulic cylinder 23 causes the main body side portion 13 (the base portion 16 and the connecting portion 19) to move to the main body portion. 1, it is operated to swing around the steering axis P1. The wheel support portion 14 (connection portion 24) is fixed to the main body side portion 13 (connection portion 19) by the fixing pin 15, so that the wheel support portion 14 and the wheel 3 are fixed to the main body side portion 13 (base portion 16 and connection portion 19). 19) and is swung (steered) around the steering axis P1.

The control unit 11 operates the control valves of the control valve unit 10 based on position data from GPS or control signals from a transmitter (not shown) operated by an operator. Driving and steering operations are performed.

(First alternative embodiment of the invention)
1 to 6, the configuration in which the main body side portion 13 extends downward along the vertical direction from the main body portion 1 has been described, but the extending direction of the main body side portion 13 is not necessarily downward in the vertical direction. It may be inclined in the front-rear direction or in the left-right direction with respect to the vertical direction.
In this configuration, it is preferable that the wheel support portion 14 is configured to be slidable relative to the main body side portion 13 along the extending direction of the main body side portion 13 .

(Second alternative embodiment of the invention)
The connection portion 19 of the main body side portion 13 is formed in a square pipe shape, and the connection portion 24 of the wheel support portion 14 is formed in a round pipe shape. It may be configured such that 14 round pipe-shaped connecting portions 24 are inserted.

1 to 6 and the above-described configuration, one of the main body side portion 13 and the wheel support portion 14 is configured in a square pipe shape along the vertical direction, and the main body side portion 13 and the wheel support portion 14 The other is configured in a round pipe shape along the vertical direction, and the other round pipe shape of the main body side portion 13 and the wheel support portion 14 is inserted into one of the square pipe shapes of the main body side portion 13 and the wheel support portion 14 As a result, the wheel support portion 14 is slidably supported by the main body side portion 13 along the vertical direction (extending direction of the main body side portion 13).

(Third alternative embodiment of the invention)
One of the connection portion 19 of the main body side portion 13 and the connection portion 24 of the wheel support portion 14 is formed in the shape of a solid round bar, and the other of the connection portion 19 of the main body side portion 13 and the connection portion 24 of the wheel support portion 14 is , a square pipe or a round pipe, and a solid round bar may be inserted into the square pipe or the round pipe.

One of the connection portion 19 of the main body side portion 13 and the connection portion 24 of the wheel support portion 14 is configured in the shape of a square pipe or a solid square bar, and the connection portion 19 of the main body side portion 13 and the connection portion of the wheel support portion 14 The other side of 24 may be configured in the shape of a square pipe into which a square pipe or a solid square bar is inserted.

One of the connection portion 19 of the main body side portion 13 and the connection portion 24 of the wheel support portion 14 is configured in the shape of a round pipe or a solid round bar, and the connection portion 19 of the main body side portion 13 and the connection portion of the wheel support portion 14 The other of 24 may be configured in the shape of a round pipe into which a round pipe or a solid round bar is inserted.

With the configuration shown in FIGS. 1 to 6 and the configuration described above, at least one of the main body side portion 13 and the wheel support portion 14 is configured in a pipe shape along the vertical direction, and the main body side portion 13 and the wheel support portion By inserting the other of the main body side portion 13 and the wheel support portion 14 into one of the pipe-shaped portions 14, the wheel support portion 14 extends along the vertical direction (extension direction of the main body side portion 13) of the main body side portion 13. slidably supported.

(Fourth alternative embodiment of the invention)
Instead of the fixing pin 15, a fixing bolt (not shown), a buckle (not shown), a fixing hook (not shown), or the like may be used as the fixing portion. Seven or more fixing holes 19b may be formed in the connection portion 19 of the main body side portion 13 .

(Fifth alternative embodiment of the invention)
The fixing hole 19b of the connecting portion 19 of the main body side portion 13 and the fixing hole 24a of the connecting portion 24 of the wheel support portion 14 are eliminated, and the connecting portion of the main body side portion 13 is fixed by a belt-shaped fixing portion (not shown). 19 and the connection portion 24 of the wheel support portion 14 may be tightened to fix the connection portion 24 of the wheel support portion 14 to the connection portion 19 of the main body side portion 13 .
According to this configuration, the fixing position of the connection portion 24 of the wheel support portion 14 can be continuously set at any desired position.

(Sixth alternative embodiment of the invention)
In the body side portion 13, the connection portion 19 is fixed to the base portion 16, or the connection portion 19 and the base portion 16 are integrally configured so that the connection portion 19 cannot be attached to or removed from the base portion 16. good too.
According to this configuration, the main body side portion 13 (boss portion 17 of the base portion 16 ) may be configured to be detachable from the fulcrum portion 21 of the main body portion 1 . As a result, the entire main body side portion 13 is replaced with another main body side portion 13 having a different connecting portion 19 length.

(Seventh alternative embodiment of the invention)
In the wheel support portion 14 , the fender 28 may be detachably attached to the wheel support portion 14 .

(Eighth alternative embodiment of the invention)
Instead of the hydraulic cylinder 23, an electric cylinder (not shown) or an electric motor (not shown) may be used as the steering actuator. Instead of a hydraulic motor type drive motor 27, an electric motor type drive motor 27 may be used.
According to this configuration, a battery (not shown) may be provided in place of the hydraulic pressure supply section 9, and a current controller (not shown) may be provided in place of the control valve section 10.

(Ninth alternative embodiment of the invention)
Instead of four wheel support mechanisms 2 and wheels 3 , six or eight wheel support mechanisms 2 and wheels 3 may be provided in the main body 1 .

The present invention can be applied to work vehicles.

REFERENCE SIGNS LIST 1 main body 2 wheel support mechanism 3 wheel 13 main body side 14 wheel support 15 fixing pin (fixing part)
23 hydraulic cylinder (steering actuator)
27 drive motor 28 fender P1 steering shaft center

Claims (9)

A main body, a plurality of wheel support mechanisms provided in the main body, and wheels for running supported under each of the wheel support mechanisms,
In the wheel support mechanism,
a body side portion attached to the body portion and arranged to extend downward from the body portion;
a wheel support portion supported by the main body side portion so as to support the wheel and be slidable along the extending direction of the main body side portion;
a fixing portion capable of fixing and releasing the fixing of the wheel support portion to the side portion of the main body ;
The wheel support portion has a connection portion that is fixedly and unfixably connected to the main body side portion, and a support portion that is connected to the connection portion. A work vehicle in which a drive motor for driving a wheel is supported, and the wheel is supported outside the supporting portion in the machine body width direction . The main body side portion extends downward along the vertical direction from the main body portion,
The work vehicle according to claim 1, wherein the wheel support portion is supported by the side portion of the main body so as to be slidable along the vertical direction. At least one of the main body side portion and the wheel support portion is configured in a pipe shape,
By inserting the other of the body side portion and the wheel support portion into the pipe-shaped one of the body side portion and the wheel support portion, the wheel support portion extends along the extending direction of the body side portion. The work vehicle according to claim 1 or 2, which is slidably supported on the side portion of the main body. One of the main body side portion and the wheel support portion is configured in a square pipe shape,
The other of the main body side portion and the wheel support portion is configured in a round pipe shape,
By inserting the round pipe-shaped other of the main body side portion and the wheel support portion into one of the square pipe-shaped main body side portion and the wheel support portion, the wheel support portion becomes the main body side portion. 4. The work vehicle according to claim 3, which is slidably supported on the side portion of the main body along the extending direction. the main body side portion is supported by the main body portion so as to be swingable about a steering axis along the extending direction of the main body side portion;
The work vehicle according to any one of claims 1 to 4, further comprising a steering actuator capable of swinging the main body side portion about the steering axis with respect to the main body portion. The support portion includes a vertically extending portion to which the driving motor is attached and which extends vertically along the side surface of the drive motor, and an upper end portion of the vertically extending portion extending above the upper surface of the drive motor in the vehicle body width direction. and an upwardly extending portion extending inwardly, wherein the supporting portion is connected to the connecting portion via a boss fixed to the upper surface of the upwardly extending portion. The work vehicle according to item 1. The work vehicle according to any one of claims 1 to 6, wherein a fender is fixedly or detachably attached to the wheel support portion so as to be arranged above the wheel. 8. Any one of claims 1 to 7, wherein the fixing portion can fix and release the wheel support portion to the main body side portion at any position or a plurality of positions along the extending direction of the main body side portion. or the work vehicle described in paragraph 1. The work vehicle according to any one of claims 1 to 8, wherein the main body side portion is detachable from the main body portion.

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