Work vehicle

Abstract

To provide a work vehicle configured so that an output pedal controls output of a prime moving part, which is configured so that a travelling speed of the work vehicle can be kept at a desired travelling speed.SOLUTION: A work vehicle is equipped with an output pedal 21 that controls output of a prime moving part, an energizing member 26 that energizes the output pedal 21 to a return side, and a brake pedal that controls a brake for travelling in a braking state, which is provided with a holding part 34 that can operate the output pedal 21 in a holding state where the pedal is held at an arbitrary position where the pedal is stepped on and operated and a release state where the holding of the output pedal 21 is released, and an artificial operation tool 38 that artificially operates the holding part 34 in the holding state. The work vehicle is further provided with a brake linkage part 36 that operates the holding part 34 in the release state, when the brake pedal is stepped on and operated in the holding state, and an output linkage part 32 that operates the holding part 34 in the release state, when the output pedal 21 is stepped on and operated in the holding state.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to the configuration of a gear change operation system in a work vehicle. [Background technology]

[0002] As disclosed in Patent Document 1, there is a work vehicle configured so that the power of an engine (corresponding to a driving part) is transmitted to the front and rear wheels via a belt-type continuously variable transmission.

[0003] In Patent Document 1, the driver operates the engine output by depressing an accelerator pedal (corresponding to an output pedal) that operates the accelerator part of the engine. When the accelerator pedal is depressed and the engine speed increases, the continuously variable transmission is operated to a higher speed accordingly, and when the accelerator pedal is released and the engine speed decreases, the continuously variable transmission is operated to a lower speed accordingly. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-51507 Summary of the Invention [Problem to be solved by the invention]

[0005] When a work vehicle is used to spray, for example, herbicides or snow-melting agents, it is necessary to run the work vehicle at a constant running speed. In this case, the work vehicle of Patent Document 1 requires the driver to keep the accelerator pedal depressed so that the vehicle's traveling speed is maintained at the desired traveling speed, so there is room for improvement.

[0006] The present invention aims to configure a work vehicle that is configured so that the output of a driving part such as an engine or electric motor can be operated by an output pedal, and that the travel speed of the work vehicle can be easily maintained at a desired travel speed. [Means for solving the problem]

[0007] The work vehicle of the present invention comprises an output pedal for controlling the output of a driving unit, a biasing member for biasing the output pedal in the return direction, a brake pedal for operating a brake for travelling to a braking state, and a holding unit operable to hold the output pedal in a holding state where the output pedal is held at any position where the output pedal is depressed, and a release state where the holding of the output pedal is released. It is provided at a position higher than the output pedal, The brake control system is provided with a manual operation tool that manually operates the holding portion to the holding state, a brake linkage that operates the holding portion to the release state when the brake pedal is depressed in the holding state, and an output linkage that operates the holding portion to the release state when the output pedal is depressed in the holding state. An operating member linked to the output pedal is provided at the output linkage section, at a position above the output pedal and at a height between the manual operating device and the output pedal, and is operated in conjunction with the output pedal being stepped on and released. The holding section is engaged with the operating member to hold the operating member, thereby entering the holding state, and the holding section is operated to move away from the operating member, thereby entering the release state.

[0008] According to the present invention, when the driver depresses the output pedal, the output (rotation speed) of the driving unit increases, and when the driver takes his / her foot off the output pedal, the output pedal is returned by the biasing member, and the output (rotation speed) of the driving unit decreases.

[0009] When the driver has depressed the output pedal to obtain the desired travel speed, he or she operates the manual operating device to place the holding section in the held state and hold the output pedal. Even if the driver takes his or her foot off the output pedal, the output pedal is held in the desired position, so the travel speed of the work vehicle is maintained at the desired travel speed. This makes it possible to easily maintain the travel speed of the work vehicle at a desired travel speed, thereby improving the operability of the work vehicle's gear change operating system.

[0010] According to the present invention, when the output pedal is held in the desired position and the work vehicle is running, when the driver steps on the brake pedal, the brake linkage unit operates the holding unit to the released state, and the biasing member operates the output pedal to return, reducing the output (rotation speed) of the driving unit. This allows the output (rotation speed) of the motor unit to be maintained at an increased level, while avoiding the situation where the work vehicle's travel speed is forced to slow down (the work vehicle is forced to stop), and allows the work vehicle's travel speed to be slowed down naturally (the work vehicle can be stopped naturally).

[0011] According to the present invention, when the output pedal is held in the desired position and the work vehicle is running, when the driver depresses the output pedal, the output linkage unit operates the holding unit to a released state, and the output pedal can be depressed (to increase the output (rotation speed) of the driving unit) without interference from the holding unit.

[0012] As described above, when the output pedal is held in the desired position and the work vehicle is traveling, the holding portion is operated to the released state by stepping on the brake pedal, and the holding portion is operated to the released state by stepping on the output pedal, thereby improving the operability of the work vehicle's gear shift operating system.

[0013]

[0014] According to the present invention, the manual operating device operated by the driver is provided at a position higher than the output pedal, making it easier for the driver to operate the manual operating device, thereby improving the operability of the manual operating device.

[0015] When the output pedal is configured to be held in a desired position, it is not preferable to configure the holding portion to act directly on the output pedal to hold the output pedal, as this would result in the driver's foot being near the output pedal.

[0016] According to the present invention, in the output linkage section, an operating member that operates in conjunction with the output pedal being pressed down and released is provided at a position above the output pedal, at a height between the manual operating device and the output pedal, and a holding section acts on the operating member. As a result, the holding portion and the operating member are positioned away from the driver's feet, so that the holding portion and the operating member are less likely to interfere with the driver's feet.

[0017] According to the present invention, the operating member is provided above the output pedal rather than at a position distant from the output pedal in the left-right direction, and the operating member is provided at a position lower than the manual operating tool. Therefore, the output pedal and the operating member are not separated more than necessary, and the linking structure between the output pedal and the operating member can be constructed without difficulty.

[0018] In the present invention, it is preferable that the manual operating tool is provided at a position separated from the output pedal in the left-right direction, is connected between the manual operating tool and the holding part, and is provided with a linking member that transmits the operation of the manual operating tool to the holding part so that the holding part is operated to the holding state.

[0019] In a work vehicle, it is conceivable that an air conditioner operation switch or the like is located above the output pedal. According to the present invention, when the manual operator is installed at a position higher than the output pedal, the manual operator is installed at a position separated from the output pedal in the left-right direction, and the linking member connects the manual operator to the holder, thereby enabling the manual operator to be installed comfortably while avoiding the operation switches of the air conditioner, etc.

[0020] In the present invention, it is preferable that the brake linkage portion is configured such that, when the brake pedal is depressed in the held state, the brake pedal operates to move the holding portion away from the operating member.

[0021] According to the present invention, when the output pedal is held in the desired position and the work vehicle is running, when the driver steps on the brake pedal, the brake pedal acts directly on the holding portion in the brake linkage portion, moving the holding portion away from the operating member. As a result, the force of the driver's foot acts directly on the holding portion via the brake pedal, so that when the brake pedal is depressed, the holding portion is operated to the released state without delay.

[0022] In the present invention, it is preferable that a support member is provided that supports the output pedal so that the output pedal can be depressed and returned, and the biasing member is connected across the output pedal and the support member.

[0023] According to the present invention, the biasing member that biases the output pedal in the return direction is connected across the support member that supports the output pedal and the output pedal, which is advantageous in terms of simplifying the structure because the support member that supports the output pedal also serves as a mounting member for the biasing member.

[0024] In the present invention, it is preferable that an upper link is supported on the support member so as to be able to swing up and down and extends rearward from the support member, and a lower link is supported on the support member so as to be able to swing up and down and extends rearward from the support member, and that the output pedal is connected to the rear of the upper link and the rear of the lower link.

[0025] According to the present invention, the output pedal is supported by a support member via an upper link and a lower link, thereby achieving a state in which the output pedal moves parallel up and down, compared to a configuration in which the output pedal is supported so that it can swing up and down around an axis along the left-right direction. This makes it easier for the driver to operate the output pedal in a work vehicle where the driver sits in a relatively upright position compared to a general passenger vehicle.

[0026] In the present invention, the operating member is supported so as to swing in a first direction about a first axis in conjunction with a depression operation of the output pedal, and to swing in a second direction about the first axis that is opposite to the first direction in conjunction with a return operation of the output pedal, the operating member is provided with a plurality of first receiving portions along a radial direction of the first axis, and a plurality of first inclined portions that face in the first direction and in a direction approaching the first axis from an outer end of the first receiving portion in the radial direction of the first axis, the holding portion is supported so as to be swingable about a second axis that is parallel to the first axis, and the holding portion is provided with a second receiving portion along a radial direction of the second axis, and Preferably, a second inclined portion is provided from the radial outer end of the second receiving portion about the second axis toward the second direction and toward the second axis, and when the holding portion is engaged with the operating member and the first receiving portion and the second receiving portion abut against each other, the return operation of the output pedal by the biasing member is stopped, the operating member is held, and the holding state is achieved, and when the output pedal is depressed in the holding state, the operating member swings in the first direction, pressing the first inclined portion against the second inclined portion, and the holding portion is operated to move away from the operating member, thereby achieving the release state.

[0027] According to the present invention, the operating member of the output linkage is provided with a plurality of first receiving portions and a plurality of first inclined portions, and the holding portion is provided with second receiving portions that are substantially parallel to the first receiving portions and second inclined portions that are inclined in the opposite direction to the first inclined portions.

[0028] When the holding portion is engaged with the operating member by a manual operating tool, the second receiving portion of the holding portion comes into contact with one of the first receiving portions of the operating member. In this case, since the operating member is biased in the second direction by the biasing member, the first receiving portion of the operating member is pressed against the second receiving portion of the holding portion and stopped, thereby holding the output pedal (operating member). This state is the held state. When the brake pedal is depressed, the second receiving portion of the holding portion is moved away from the first receiving portion of the operating member, thereby obtaining a released state.

[0029] In the above-described holding state, when the output pedal is depressed, the operating member is swung in the first direction, and the first inclined portion of the operating member is pressed against the second inclined portion of the holding portion. In this case, because the first inclined portion of the operating member is inclined toward a first direction and the second inclined portion of the holding portion is inclined toward a second direction opposite to the first direction, when the first inclined portion of the operating member is pressed against the second inclined portion of the holding portion, a component force is generated that pushes the holding portion in a direction away from the operating member, and this component force operates the second receiving portion of the holding portion away from the first receiving portion of the operating member, thereby obtaining the released state.

[0030] As described above, by devising the shapes of the first receiving portion and first inclined portion of the operating member of the output linkage portion, and the second receiving portion and second inclined portion of the holding portion, it is possible to obtain an output linkage portion with a simple structure that operates the holding portion to a released state when the output pedal is depressed in a held state. [Brief explanation of the drawings]

[0031] [Figure 1] FIG. [Figure 2] FIG. 10 is a rear view of the vicinity of the front panel. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 2 is a left side view of the vicinity of the operating member and the holding portion. [Figure 6] 10 is a left side view of the vicinity of the operating member and the holding portion in a holding state in which the holding portion is engaged with the operating member. FIG. [Figure 7] 7 is a left side view of the vicinity of the operating member and the holding portion in a released state in which the accelerator pedal is depressed from the state shown in FIG. 6 and the holding portion is moved away from the operating member. FIG. [Figure 8] 10 is a left side view of the vicinity of the brake pedal in a holding state in which the holding portion is engaged with the operating member. FIG. [Figure 9]9 is a left side view of the vicinity of the brake pedal in a released state in which the brake pedal is depressed from the state shown in FIG. 8 and the holding portion is moved away from the operating member. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0032] A multipurpose work vehicle is shown in Figures 1 to 9, and in Figures 1 to 9, F indicates the forward direction, B indicates the backward direction, U indicates the upward direction, D indicates the downward direction, R indicates the right direction, and L indicates the left direction.

[0033] (Overall configuration of the work vehicle) As shown in Figure 1, a body frame 3 is supported by right and left front wheels 1 and right and left rear wheels 2. The body frame 3 has a floor frame 4, a ROPs frame 5, a rear frame 6, etc. The rear frame 6 is connected to the rear of the ROPs frame 5 and extends rearward, and a loading platform 11 is supported by the rear frame 6.

[0034] Right and left front seats 7 and right and left rear seats 8 are mounted on a floor frame 4, and a roof protection frame 5 is connected to the floor frame 4 so as to cover the front seats 7 and rear seats 8. A windshield (not shown) and a rear glass (not shown) are mounted at the front and rear of the roof protection frame 5, a roof 9 is mounted on top of the roof protection frame 5, and doors 10 are mounted at the front and rear of the roof protection frame 5.

[0035] An engine 12 (corresponding to a driving part), a continuously variable transmission 13, a transmission case 14 and rear wheels 2 are supported by a lower frame 15, and the lower frame 15 is connected to the floor frame 4 and the rear frame 6.

[0036] The continuously variable transmission 13 is configured as a belt-type continuously variable transmission. When the rotation speed of the engine 12 increases, the continuously variable transmission 13 is automatically operated to the high speed side accordingly, and when the rotation speed of the engine 12 decreases, the continuously variable transmission 13 is automatically operated to the low speed side accordingly. Inside the transmission case 14, there are provided an auxiliary transmission (not shown) capable of shifting to three forward speeds and one reverse speed, and a rear wheel differential (not shown).

[0037] The power of the engine 12 is transmitted to the continuously variable transmission 13, where it is changed in speed, then to the auxiliary transmission in the transmission case 14, where it is changed in speed, then to the rear wheel differential device, and from the rear wheel differential device to the rear wheels 2. The power branched off between the auxiliary transmission and the rear wheel differential device is transmitted to the front wheel differential device 17 via the transmission shaft 16, and from the front wheel differential device 17 to the front wheels 1.

[0038] (Configuration of the front part of the inside of the ROPS frame) As shown in FIGS. 1 and 2, inside the ROP frame 5, a front panel 18 is provided in front of the front seat 7.

[0039] A steering handle 19 for steering the front wheels 1 and a shift lever 20 for operating the auxiliary transmission of the transmission case 14 are provided on the upper left portion of the front panel 18 (in front of the left front seat 7). An accelerator pedal 21 (corresponding to an output pedal) and a brake pedal 22 are provided below the left portion of the front panel 18 (in front of the left front seat 7).

[0040] (Accelerator pedal support structure) As shown in Figures 3 and 4, a support member 23 is provided inside the front panel 18 (see Figure 2). A flat upper link 24 is supported by the support member 23 so as to be able to swing up and down about an axis P3 along the left-right direction, and extends rearward from the support member 23. A flat lower link 25 is supported by the support member 23 so as to be able to swing up and down about an axis P4 along the left-right direction, and extends rearward from the support member 23.

[0041] The accelerator pedal 21 is connected to the rear of the upper link 24 and the rear of the lower link 25, and an arm 25a connected to the front of the lower link 25 is connected to a potentiometer-type position sensor (not shown) via a connecting rod (not shown).

[0042] A spring 26 (corresponding to a biasing member) is connected between the upper attachment portion 23a of the support member 23 and the upper link 24, and the accelerator pedal 21 is biased in the return direction (upward) by the spring 26. A stopper portion 27 is provided below the accelerator pedal 21 to set the limit position for depression of the accelerator pedal 21.

[0043] With the above configuration, accelerator pedal 21 is supported by support member 23 so as to be capable of being depressed and released. A spring 26 (a biasing member) that biases accelerator pedal 21 in the release direction is connected between accelerator pedal 21 and support member 23 via upper link 24.

[0044] The operating position of accelerator pedal 21 is detected by a position sensor via lower link 25, and based on the detected value of the position sensor, an accelerator section of engine 12 is operated by an actuator (not shown), thereby manipulating the output of engine 12 (fly-by-wire type). In this case, a wire (not shown) may be configured to connect between accelerator pedal 21 (arm 25a of lower link 25) and the accelerator section of engine 12.

[0045] (Configuration of output linkage section) 3 and 4, a support member 28 is provided above the support member 23. A flat-plate-shaped operating member 29 is provided, and a fulcrum shaft 29c connected to the operating member 29 is supported by the support member 28 so as to be rotatable about an axis P1 (corresponding to a first axis) along the left-right direction. As a result, the operating member 29 is supported by the support member 28 so as to be swingable about the axis P1, and extends forward from the axis P1.

[0046] An arm 29d is connected to the end of the fulcrum shaft 29c of the operating member 29, and a linking rod 30 is connected between the arm 29d of the operating member 29 and the upper link 24. A spring 31 that biases the operating member 29 in the clockwise direction in Figure 3 is attached to the fulcrum shaft 29c of the operating member 29. As a result, an output linkage 32 having a support member 28, an operating member 29, a linkage rod 30, and a spring 31 is provided.

[0047] 5, the front end of the operating member 29 is formed in a sawtooth shape, and a plurality of first receiving portions 29a extending along the radial direction of the axis P1 are provided at the front end of the operating member 29. A plurality of first inclined portions 29b are provided at the front end of the operating member 29, and the first inclined portions 29b are inclined from the outer end of the first receiving portions 29a in the radial direction of the axis P1 toward the first direction A1 and toward the axis P1.

[0048] With the above configuration, as shown in Figures 3, 4, and 5, when the accelerator pedal 21 is depressed (operated downward), the upper link 24 operates the connecting rod 30 downward in conjunction with the depression of the accelerator pedal 21, and the fulcrum shaft 29c and arm 29d of the operating member 29 operate the operating member 29 to swing around the axis P1 in the first direction A1 (counterclockwise in Figure 5).

[0049] When the accelerator pedal 21 is operated to return (upward) by the spring 26, the connecting rod 30 is operated upward by the upper link 24 in conjunction with the operation of returning the accelerator pedal 21, and the fulcrum shaft 29c and arm 29d of the operating member 29, and the spring 31 cause the operating member 29 to swing around the axis P1 in a second direction A2 (clockwise in Figure 5) opposite to the first direction A1.

[0050] (Configuration of holding part) 3 and 4, a support member 33 is provided above the support member 23. A holding portion 34 is supported by the support member 33 so as to be swingable around an axis P2 (corresponding to a second axis) that extends in the left-right direction and is parallel to the axis P1.

[0051] The holding portion 34 is formed by bending a plate material into a channel shape, and an engagement portion 35 and a linking arm 36 (corresponding to the brake linking portion) are connected to the holding portion 34. A spring 37 is connected across the mounting portion 33a of the support member 33 and the holding portion 34, and the holding portion 34 is biased by the spring 37 in the clockwise direction in FIG.

[0052] 5, a second receiving portion 35a and a second inclined portion 35b are provided on the engaging portion 35. The second receiving portion 35a is formed along the radial direction of the axis P2. The second inclined portion 35b is inclined from the outer end of the second receiving portion 35a in the radial direction of the axis P2 toward the second direction A2 and toward the axis P2.

[0053] As shown in Figures 2, 3, and 4, an operating knob 38 (corresponding to an artificial operating device) is provided on the front panel 18 adjacent to the shift lever 20, and a wire 39 (corresponding to a connecting member) is connected between the operating knob 38 and the holding portion 34.

[0054] When the operating knob 38 is pulled rearward and upward, the operation of the operating knob 38 is transmitted to the holding portion 34 via the wire 39, causing the holding portion 34 to swing counterclockwise around the axis P2 in Figures 3 and 5, and the holding portion 34 (engagement portion 35) is engaged with the operating member 29 (holding state).

[0055] The above configuration provides an operation knob 38 (manual operation tool) for manually operating the holding portion 34 to the holding state. The operation knob 38 (manual operation tool) is provided at a position (front panel 18) higher than the accelerator pedal 21 (output pedal), and at a position separated from the accelerator pedal 21 (output pedal) in the left-right direction (see FIG. 2).

[0056] In the output linkage section 32, an operating member 29 linked to the accelerator pedal 21 (output pedal) is provided above the accelerator pedal 21 (output pedal) and at a height between the operating knob 38 (manual operating device) and the accelerator pedal 21 (output pedal), and the operating member 29 operates in conjunction with the accelerator pedal 21 (output pedal) being depressed and released.

[0057] (Accelerator pedal held) To maintain the vehicle's travel speed at a desired speed, the driver may perform the following operations.

[0058] As shown in FIG. 5, when the holding portion 34 (engagement portion 35) is released from the operating member 29 and is in a released state, the driver can press and release the accelerator pedal 21 to cause the operating member 29 to swing around the axis P1, thereby controlling the output (rotation speed) of the engine 12.

[0059] As shown in Figures 5 to 3 and 6, when the driver depresses accelerator pedal 21 to obtain the desired driving speed, while continuing to depress accelerator pedal 21, he or she pulls operating knob 38 to swing holding portion 34 (engagement portion 35) around axis P2 in the counterclockwise direction in Figure 6, thereby engaging holding portion 34 (engagement portion 35) with operating member 29.

[0060] 6, when the holding portion 34 (engagement portion 35) is engaged with the operating member 29, the second receiving portion 35a of the holding portion 34 (engagement portion 35) comes into contact with one of the first receiving portions 29a of the operating member 29. In this case, since the operating member 29 is biased in the second direction A2 by the springs 26, 31 (see FIGS. 3 and 4), the first receiving portion 29a of the operating member 29 is pressed against the second receiving portion 35a of the holding portion 34 (engagement portion 35).

[0061] The frictional resistance between the first receiving portion 29a of the operating member 29 and the second receiving portion 35a of the holding portion 34 (engagement portion 35) is stronger than the biasing force of the spring 37. As a result, the holding portion 34 (engagement portion 35) is not operated to move away from the operating member 29 by the spring 37, the operating member 29 is held by the holding portion 34 (engagement portion 35), the return operation of the accelerator pedal 21 by the springs 26, 31 is stopped, and the accelerator pedal 21 is held. This state is the held state.

[0062] Even if the driver takes his / her foot off the accelerator pedal 21, the accelerator pedal 21 is held at the desired position where it was depressed (held state), so the travel speed of the work vehicle is maintained at the desired travel speed.

[0063] With the above configuration, the driver can hold the accelerator pedal 21 at any position by depressing the accelerator pedal 21 and pulling the operating knob 38 to engage the holding portion 34 (engagement portion 35) with the operating member 29 (holding state).

[0064] (Accelerator pedal released by depressing the brake pedal) 4, 8, and 9, a brake pedal 22 is provided below the left portion of the front panel 18 (see FIG. 2). The brake pedal 22 has an arm 22a supported so as to be swingable about an axis P5 extending in the left-right direction, and a foot 22b provided at the bottom of the arm 22a.

[0065] When the pedal 22b of the brake pedal 22 is depressed and the brake pedal 22 is operated in a depression direction A3 around the axis P5, a travel brake (not shown) is operated to a braking state. The brake pedal 22 is biased in a return direction A4 by a spring (not shown).

[0066] The arm 22a of the brake pedal 22 is provided in front of the linking arm 36. As shown in Figure 8, in a holding state in which the holding portion 34 (engagement portion 35) is engaged with the operating member 29, the linking arm 36 is located near the front of the arm 22a of the brake pedal 22.

[0067] In the holding state in which the holding portion 34 (engagement portion 35) is engaged with the operating member 29, as shown in Figure 9, when the step portion 22b of the brake pedal 22 is stepped on and the brake is operated to a braking state (stepping direction A3), the arm 22a of the brake pedal 22 abuts against the linkage arm 36 and pushes the linkage arm 36 forward, and the holding portion 34 (engagement portion 35) is operated forward and away from the operating member 29 around the axis P2, and the holding portion 34 (engagement portion 35) enters a released state.

[0068] When the holding portion 34 (engagement portion 35) is released from the operating member 29 and put into a released state, the accelerator pedal 21 is returned by the springs 26, 31 (see Figures 3 and 4), and the output (rotation speed) of the engine 12 decreases.

[0069] Thereafter, even if the brake pedal 22 is returned (return direction A4), the holding portion 34 (engagement portion 35) is maintained in the released state in which it is moved away from the operating member 29 by the spring 37 (see FIGS. 3 to 6).

[0070] In the released state where the holding portion 34 (engagement portion 35) is operated away from the operating member 29, even if the brake pedal 22 is stepped on (stepping direction A3) and returned (return direction A4), the brake pedal 22 (arm 22a) and the connecting arm 36 do not interfere with each other.

[0071] With the above configuration, when the brake pedal 22 is depressed while the holding portion 34 (engagement portion 35) is engaged with the operating member 29 in a holding state, the holding portion 34 (engagement portion 35) is operated to a released state by the linkage arm 36 (brake linkage portion).

[0072] When the holding portion 34 (engagement portion 35) is operated to a released state by being released from the operating member 29, the hold on the accelerator pedal 21 (output pedal) is released, and the driver can press and release the accelerator pedal 21, causing the operating member 29 to swing around the axis P1, thereby manipulating the output (rotation speed) of the engine 12.

[0073] (Accelerator pedal release operation by depressing the accelerator pedal) As shown in Figure 6, in the holding state in which the holding portion 34 (engagement portion 35) is engaged with the operating member 29, the second receiving portion 35a of the holding portion 34 (engagement portion 35) abuts against one of the first receiving portions 29a of the operating member 29, and since the operating member 29 is biased in the second direction A2 by springs 26, 31 (see Figures 3 and 4), the first receiving portion 29a of the operating member 29 is pressed against the second receiving portion 35a of the holding portion 34 (engagement portion 35).

[0074] In the above-described state, when accelerator pedal 21 is depressed, operating member 29 is pivoted in first direction A1 about axis P1 in conjunction with the depression of accelerator pedal 21. Accordingly, of first inclined portion 29b of operating member 29, the first inclined portion 29b of operating member 29 adjacent to second inclined portion 35b of holding portion 34 (engagement portion 35) is pressed in first direction A1 by second inclined portion 35b of holding portion 34 (engagement portion 35).

[0075] In this case, the first inclined portion 29b of the operating member 29 is inclined toward the first direction A1, and the second inclined portion 35b of the holding portion 34 (engagement portion 35) is inclined toward the second direction A2, which is opposite to the first direction A1.

[0076] As shown in Figure 7, when the first inclined portion 29b of the operating member 29 is pressed against the second inclined portion 35b of the holding portion 34 (engagement portion 35) in the first direction A1, a component force is generated that pushes the holding portion 34 (engagement portion 35) in a direction (forward) away from the operating member 29, and this component force operates the second receiving portion 35a of the holding portion 34 (engagement portion 35) away from the first receiving portion 29a of the operating member 29.

[0077] When the second receiving portion 35a of the holding portion 34 (engaging portion 35) is moved away from the first receiving portion 29a of the operating member 29, the spring 37 causes the holding portion 34 (engaging portion 35) to swing further forward around the axis P2, and the holding portion 34 (engaging portion 35) is moved away from the operating member 29. This state is the released state. Even when the accelerator pedal 21 is released, the holding portion 34 (engagement portion 35) is maintained in a released state in which it is separated from the operating member 29 by the spring 37.

[0078] With the above configuration, when the accelerator pedal 21 is depressed in a holding state in which the holding portion 34 (engagement portion 35) is engaged with the operating member 29, the holding portion 34 (engagement portion 35) is operated to a release state by the operating member 29 (output linkage portion 32).

[0079] When the holding portion 34 (engagement portion 35) is operated to a released state by being released from the operating member 29, the hold on the accelerator pedal 21 (output pedal) is released, and the driver can press and release the accelerator pedal 21, causing the operating member 29 to swing around the axis P1, thereby manipulating the output (rotation speed) of the engine 12.

[0080] (First Alternative Embodiment of the Invention) The wire 39 may be eliminated, and a connecting rod (not shown) (corresponding to a connecting member) or a connecting link (not shown) (corresponding to a connecting member) may be connected between the operating knob 38 and the holding portion 34 (engagement portion 35).

[0081] According to the above-described configuration, the operation of pushing the operating knob 38 forward and downward can be transmitted to the holding portion 34 (engagement portion 35), so that by pulling and pushing the operating knob 38, the holding portion 34 (engagement portion 35) can be operated to a holding state in which it is engaged with the operating member 29, or to a release state in which it is operated away from the operating member 29. In this case, instead of the operation knob 38, an operation lever (not shown) (corresponding to a manual operation tool) may be employed.

[0082] (Second Alternative Embodiment of the Invention) Instead of the engine 12, an electric motor (not shown) may be provided as a driving unit. According to this configuration, the configuration shown in FIGS. 3 to 9 may be adopted for the output pedal (not shown) that controls the output of the electric motor. [Industrial Applicability]

[0083] The present invention can be applied to a work vehicle configured to operate the output of a driving unit such as an engine or an electric motor with an output pedal. [Explanation of symbols]

[0084] 12 Engine (power unit) 21 Accelerator pedal (output pedal) 22 Brake pedal 23 Support member 24 Top link 25 Downlink 26 Spring (biasing member) 29 Operating member 29a First receiving part 29b 1st slope 32 Output linkage section 34 Holding part 35a Second receiving part 35b 2nd slope part 36 Linkage arm (brake linkage part) 38 Operating knob (artificial operating device) 39 Wire (connecting member) A1 1st direction A2 2nd direction P1 axis (1st axis) P2 axis (second axis)

Claims

1. an output pedal for controlling the output of the driving unit; a biasing member that biases the output pedal in the return direction; a brake pedal for operating a brake for driving into a braking state; a holding section operable to change between a holding state in which the output pedal is held at an arbitrary position where the output pedal is depressed and a release state in which the holding state of the output pedal is released; an operating tool that is provided at a position higher than the output pedal and that operates the holding part manually to the holding state, a brake linkage unit that operates the holding unit to the release state when the brake pedal is depressed in the holding state; an output linkage unit that operates the holding unit to the release state when the output pedal is depressed in the held state, an operating member is provided in the output linkage section at a position above the output pedal and at a height between the manual operation device and the output pedal, the operating member being linked to the output pedal so as to operate in conjunction with the output pedal being pressed down and released, The work vehicle is in the held state when the holding portion is operated to engage with the operating member and hold the operating member, and is in the released state when the holding portion is operated to move away from the operating member.

2. the manual operation tool is provided at a position separated from the output pedal in the left-right direction, 2. The work vehicle according to claim 1, further comprising a linking member connected between the manual operating tool and the holding portion, which transmits the operation of the manual operating tool to the holding portion, thereby operating the holding portion into the holding state.

3. 3. The work vehicle according to claim 2, wherein the brake linkage portion is configured such that, when the brake pedal is depressed in the held state, the brake pedal operates to move the holding portion away from the operating member.

4. a support member that supports the output pedal so that the output pedal can be depressed and returned; 4. The work vehicle according to claim 3, wherein the biasing member is connected across the output pedal and the support member.

5. an upper link supported by the support member so as to be able to swing up and down and extending rearward from the support member; a lower link supported by the support member so as to be able to swing up and down and extending rearward from the support member; 5. The work vehicle according to claim 4, wherein the output pedal is connected to a rear portion of the upper link and a rear portion of the lower link.

6. the operating member is supported so as to swing in a first direction about a first axis in conjunction with a depression operation of the output pedal, and to swing in a second direction opposite to the first direction about the first axis in conjunction with a return operation of the output pedal, The operating member is provided with a plurality of first receiving portions along a radial direction of the first axis, and a plurality of first inclined portions extending from an outer end of the first receiving portions in the radial direction of the first axis toward the first direction and toward a direction approaching the first axis, the holding portion is supported so as to be swingable about a second axis parallel to the first axis, the retaining portion is provided with a second receiving portion along a radial direction of the second axis, and a second inclined portion extending from an outer end of the second receiving portion in the radial direction of the second axis toward the second direction and toward the second axis, When the holding portion is engaged with the operating member and the first receiving portion and the second receiving portion come into contact with each other, the returning operation of the output pedal by the biasing member is stopped, and the operating member is held to enter the held state. A work vehicle as described in any one of claims 1 to 5, wherein when the output pedal is depressed in the held state, the operating member swings in the first direction, pressing the first inclined portion against the second inclined portion, and the holding portion is operated away from the operating member, thereby entering the released state.

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