JP2000335438A - Paddy field working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce damage of a furrow pan according to a small turn revolution. SOLUTION: This machine is provided with an interlocking mechanism A for clutch operation interposing clutches 96 intermitting transmission to left and right driving rear wheels 2 and brakes 99 braking the driving rear wheels 2 in a state that the clutches 96 are located at transmission upper sides of the brakes 99 and interlocking the clutches 96 with front wheel steering mechanisms ST so that the clutches 96 at revolution inside may be reversibly released and operated according to steering operations of set angles or more from straight advancing states of front wheels for steering 1. The machine is provided with an interlocking mechanism B for brake operation for interlocking the clutches 96 and the brakes 99 with a brake pedal BP so that both of the brakes 99 may be simultaneously braked and operated after both of the clutches 96 are simultaneously released and operated according to stepping operation of the brake pedal BP.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission system for left and right driving rear wheels, and a clutch for interrupting transmission to the driving rear wheel and a brake for braking the driving rear wheel. The present invention relates to a paddy field working machine such as a rice transplanter that is interposed in a state that is located on the transmission upper side.

[0002]

2. Description of the Related Art Conventionally, when a front steering wheel is in a straight running state, a clutch on the inside of the turn is disengaged in accordance with a steering operation at a set angle or more, then a brake is operated to operate the front wheel to an angle less than a set angle. When the front wheel is steered by more than the set angle, the inside of the turn is turned when the front wheel is steered by more than the set angle. The vehicle automatically brakes the rear wheels to make a small turn.

[0003]

However, according to the above-mentioned prior art, when the vehicle makes a small turn on the headland, the drive rear wheel on the inside of the turn is braked and dragged on the till in a state where the rotation is stopped. The degree to which the tills were roughened was great.

[0004] It is an object of the present invention to reduce trollage of a cultivator due to small turning.

[0005]

The features, functions and effects of the present invention according to claim 1 are as follows.

[Features] In each of the transmission systems to the left and right driving rear wheels, a clutch for intermittently transmitting power to the driving rear wheel and a brake for braking the driving rear wheel are provided such that the clutch is located on the upper transmission side than the brake. For clutch operation, the clutch is interlocked with the front wheel steering mechanism so that the clutch inside the turning is reversibly disengaged with the steering operation beyond the set angle from the straight running state of the steering front wheel Provide an interlocking mechanism,
A brake operation interlocking mechanism for interlocking a clutch and a brake with a brake pedal so that one brake pedal is provided, and the two clutches are simultaneously disengaged and operated simultaneously with the depression operation of the brake pedal. Is provided.

[Action] A clutch operating interlocking mechanism is provided to cut off the drive on the inside rear wheel by turning off the clutch on the inside of the turn in accordance with the steering operation beyond the set angle from the straight running state of the front wheels to cut off the drive to the rear wheel on the inside of the turn. Since the drive rear wheel on the inside of the turn is freely rotated, the rear wheel on the inside of the turn rotates on the till during a small turn with the front wheel steered to a set angle or more. It is possible to sufficiently suppress the drag of the driven rear wheel on the plow during the small turning operation.

Conventionally, a pair of left and right steering pedals is provided, and the left clutch is depressed halfway into the operating range to disengage the left clutch and to the end of the operating range. To operate the left brake by depressing the right steering pedal to the middle of the operating range, thereby disengaging the right clutch and depressing the end of the operating range to operate the right brake. There is also known a paddy field working machine in which a brake operation is performed. In this case, by depressing the steering pedal inside the turning partway to the middle of the operating range, the clutch inside the turning can be disengaged and actuated. By depressing the steering pedal inside the turning partway into the middle of the operating range, it is possible to make a small turn while suppressing drag of the driven rear wheel on the plow. However, in this case, in addition to the steering operation of the front wheels, not only an operation such as depressing a steering pedal is necessary, but also a difficult operation such that the depressing operation of the steering pedal is partially depressed in the operation range. The operability is poor because there is.

In contrast to this prior art, in the present invention, the clutch inside the turning inside is automatically disengaged in accordance with the steering operation of the front wheel beyond the set angle. No special operation for disengaging the clutch is required, and only the steering operation for the front wheels is required.

Further, in the above-mentioned conventional technique, when the left and right clutches are disengaged and then the left and right brakes are braked to perform braking and stopping of the vehicle traveling, the left and right steering pedals are connected. Even if one of the steering pedals is depressed, both steering pedals are simultaneously operated to the end of the operating range, but if the left and right steering pedals are forgotten to be connected, one of the steering pedals will be operated. Only the depressing operation is performed, which causes a one-brake phenomenon that lacks steering stability.

Focusing on the above point and the configuration of the present invention in which the left and right clutches are disengaged but the brakes are not operated by the steering operation with respect to the front wheels for a small turn, one brake pedal is used in the present invention. A brake operation interlocking mechanism is provided, and both left and right clutches are disengaged simultaneously with the depression operation of the brake pedal, and then both left and right brakes are operated to brake the left and right driving rear wheels. The brakes and stops for all aircraft traveling are performed, so if the brake pedal is depressed, there is no need for complicated operations such as connecting the steering pedal. Can be.

In addition, since the brake is disposed on the lower transmission side of the clutch, even if the front wheel is steered beyond the set angle and the clutch on the inside of the turn is disengaged, both the left and right driven rear wheels are braked. can do.

[Effects] Therefore, since the drag of the driving rear wheel on the plow during the small turning can be sufficiently suppressed, the small turning can be performed with less roughening of the plow.
In addition, only a steering operation to the front wheels is required to perform this operation, and a small turning can be performed with good operability, and furthermore, the braking and stopping of the aircraft traveling with excellent operability and excellent steering stability without one-brake phenomenon can be performed. Now you can do it.

The features, functions and effects of the present invention according to claim 2 are as follows.

[Features] In each of the transmission systems to the left and right driving rear wheels, a clutch for intermittently transmitting power to the driving rear wheel and a brake for braking the driving rear wheel are arranged such that the clutch is on the transmission upper side than the brake. For clutch operation, the clutch is interlocked with the front wheel steering mechanism so that the clutch inside the turning is reversibly disengaged with the steering operation beyond the set angle from the straight running state of the steering front wheel Provide an interlocking mechanism,
The clutch-operating interlocking mechanism operates the clutch by disengaging the clutch in accordance with the steering operation at a set angle or more from the straight running state of the front wheels, and the operating force in the clutch disengaging direction from the front wheel steering mechanism to the clutch after the clutch disengages. Is provided with a mechanism for preventing or suppressing the transmission of the noise.

[Operation] Similar to the present invention, a clutch operating interlocking mechanism is provided to disengage the clutch on the inside of the turning in accordance with the steering operation beyond the set angle from the straight running state of the front wheel, and to drive the inside of the turning after the driving on the inside of the turning. By cutting off the drive for the wheels,
Since the drive rear wheel inside the turning is made to freely rotate, during small turning with the front wheel steered beyond the set angle, the driving rear wheel inside the turning while rotating on the plow By moving, the drag of the driven rear wheel on the plow during the small turning can be sufficiently suppressed.

Further, similarly to the present invention, the clutch inside the turning is automatically disengaged in accordance with the steering operation of the front wheel at a set angle or more.
There is no need to perform any special operation for disengaging the clutch inside the turn, and only the steering operation for the front wheels is required.

By the way, the steering operation amount of the front wheel is larger than the on / off operation stroke of the clutch, and the front wheel may be steered after the clutch is operated.

Focusing on the above points, the transmission of the operating force in the clutch disengagement direction from the front wheel steering mechanism to the clutch after the clutch has been engaged is prevented or suppressed, so that the operation can be continued after the clutch is disengaged. The clutch is not operated any more in the disengagement direction by the steering operation of the front wheels, or it is slightly operated, so even if the front wheels are steered after the clutch disengagement operation, the clutch is forced. There is no, or little if any.

[Effect] Therefore, the dragging of the driving rear wheel on the plow during the small turning can be sufficiently suppressed, so that the small turning can be performed without damaging the plow.
In addition, only a steering operation for the front wheels is required to perform the operation, and a small turning operation can be performed with good operability. In addition, the deformation and breakage of the clutch can be suppressed and the durability can be improved.

The features, functions and effects of the present invention according to claim 3 are as follows.

[Features] In the feature of the present invention according to the first aspect, an absorbing means for absorbing an operation difference between left and right brakes due to a depression operation of a brake pedal is provided in a brake operation interlocking mechanism. is there.

[Operation] When the left and right brakes are braked by one brake pedal, the other brake is first released by a predetermined braking force before one of the brakes is brought into a predetermined braking force state in accordance with the depression operation of the brake pedal. When the power is exerted and the brake pedal cannot be operated any more, it may not be possible to operate one of the brakes to the predetermined braking force exerted state. That is, a braking operation difference may occur between the left and right brakes. Focusing on the above points, the difference in braking operation between the left and right brakes due to the depression operation of the brake pedal is absorbed by the absorbing means, so that both the left and right brakes can be operated to the predetermined braking force exerting state. it can. [Effect] Accordingly, the left and right driving rear wheels can be equally braked, while adopting a type in which the left and right brakes are operated by depressing one brake pedal.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A rice transplanter, which is an example of a paddy field working machine, includes a pair of left and right driving front wheels 1 and a pair of left and right driving rear wheels 2, as shown in FIGS. A multi-row seedling planting device 4 as an example of a paddy field working device is connected to a rear portion of the riding type self-propelled body 3 via a four-link mechanism 5 so as to be able to move up and down freely. An elevating cylinder 6 using a hydraulic cylinder for elevating and lowering is provided, and a fertilizer application device 7 is provided.

As shown in FIGS. 3 and 4, the self-propelled body 3 has a transmission case 9 for supporting the driving front wheel 1 via a front axle case 8 and a transmission case 9 for supporting the driving rear wheel 2. The engine 11 is mounted at a position near the front of the transmission case 9 of the fuselage frame having the axle case 10 and the output shaft 11a of the engine 11 is positioned laterally via the vibration isolating rubber 12 (an example of a vibration isolating material). In addition, a boarding operation unit 13 is mounted in a state located behind the engine 11.

The on-board driving section 13 includes a steering handle 14 for steering the front wheels 1, a seat 15 located behind the steering wheel 14, and a driving step S. The operation step S is arranged above the transmission case 9. The main clutch pedal CP is arranged on the left side of the foot, and one brake pedal BP is arranged on the right side.

The seedling planting apparatus 4 has a seedling rest 16 which is driven to reciprocate at a set stroke in the left-right direction, and moves up and down between the seedling outlet and the field in conjunction with the movement of the seedling rest 16. A plurality of planting mechanisms 17 for taking out the seedlings on the seedling stand 16 by the planting unit amount and planting them in the field by circulating the seedlings on the seedling stand 16 are arranged on the left and right with a spacing between the planting strips. It has a well-known basic structure in which a plurality of ground floats 18 for leveling a field to be planted by sliding are arranged at right and left intervals.

The fertilizer applicator 7 has a fertilizer hopper 19 mounted on the self-propelled body 3 and a feeder 20 for feeding the fertilizer in the fertilizer hopper 19 by a set amount in conjunction with the planting operation.
And a groove generator 21 for forming a fertilizer groove in the field as the vehicle travels and supplying the fertilizer sent into the groove, and feeding the fed fertilizer to the groove generator 21 via a hose 22. And an electric fan 23 for generating an airflow for performing the operation.

As shown in FIGS. 3 and 4, a lateral input shaft 41a is provided around the output shaft 11a of the engine 11 and interlocked therewith via a transmission 40, as shown in FIGS. The hydrostatic continuously variable transmission 41, which can be switched between forward and backward, outputs its output to the transmission case 9
Into a state of being transmitted by a horizontal shaft, and the input shaft 41 thereof.
a and the lateral output shaft 41b are connected in a state of being disposed in front and rear.

The wrapping transmission 40 is provided with the engine 1
A transmission belt 40c is wound around an output pulley 40a attached to the output shaft 11a and an input pulley 40b attached to the input shaft 41a of the hydrostatic continuously variable transmission 41, and a tension pulley for applying tension to the transmission belt 40b. 40d is provided.

The input shaft 4 of the hydrostatic continuously variable transmission 41
Reference numeral 1a extends to the other side through the front of the transmission case 9.

As shown in FIG. 4, a hydraulic pump 42 driven by an extended end of an input shaft 41a of the hydrostatic stepless transmission 41 is provided on the other side of the transmission case 9 on the left, right, and side. As shown in FIGS. 3 and 4, the upper surface of the transmission case 9 controls a torque generator 43 for hydraulic power steering interlocked with a handle shaft 14a of the steering handle 14 and the lifting cylinder 6 as shown in FIGS. And an electromagnetic hydraulic control valve 44 for lifting and lowering the working device.

The hydraulic system will be described in detail. The transmission case 9 is used as a hydraulic oil tank, and lubricating oil (hydraulic oil) in the transmission case 9 passes through an oil filter 45 attached to the left, right, left and other side surfaces of the transmission case 9. Is supplied to the hydrostatic continuously variable transmission 41 and the hydraulic pump 42, and the pressure oil from the hydraulic pump 42 is supplied to the torque generator 43, and then supplied to the lifting cylinder 6 through the hydraulic control valve 44. ing. Then, the drain of the hydrostatic continuously variable transmission 41 is returned to the front axle case 8 communicating with the transmission case 9, and the hydraulic control valve when the operation of the elevating cylinder 6 is stopped, that is, in the elevating stopped state. The drain 44 is returned to the mission case 9.

Then, in the mission case 9,
A main clutch CL for interrupting the output from the hydrostatic continuously variable transmission 41, a gear-shift type auxiliary transmission for shifting the output from the main clutch CL to high and low stages, and an output from the auxiliary transmission. A differential mechanism for transmitting to the left and right driving front wheels 1 is installed as a component of a traveling power transmission system to a traveling unit, and a one-way clutch for extracting only forward rotation among inputs of the auxiliary transmission, A component of a transmission system (planting transmission system) to the seedling planting device 4 that is divided from a traveling transmission system by a planting transmission mechanism for changing the power, and a planting clutch for intermittently switching the power. It is installed as. That is, the transmission to the traveling unit and the seedling planting device 4 is cut off by disengaging the main clutch CL. The main clutch CL is
The reversing operation is performed in accordance with the operation of depressing the main clutch pedal CP.

The rear axle case 10 is provided with a transmission mechanism for transmitting the power transmitted from the transmission case 9 via the transmission shaft 77 to the driving rear wheel 2.

As shown in FIGS. 5 and 6, the rear axle case 10 includes a transverse transmission case 93 having a transverse transmission shaft 92 interlocked with the transmission shaft 77 via bevel gears 90 and 91; A gear train 94 is provided at each of the left and right ends of the transmission case portion 93 to support the driving rear wheel 2 at its lower end and transmit the power of the lateral transmission shaft 92 to the axle 2A of the driving rear wheel 2. It comprises a pair of vertically oriented transmission case parts 95. The driving rear wheel 2
, Specifically, between each end of the horizontal transmission shaft 92 and each gear train 94, a multi-plate clutch 96 is interposed. These clutches 96 are shown in FIG.
As shown in the figure, a movable clutch housing 96 which rotates integrally with the lateral transmission shaft 92 and is movable in the axial direction.
A and a fixed clutch housing 96B interlocking with the gear train 94 are provided, and the movable clutch housing 96A is frictionally interlocked by being pressed against each other by the axial movement in a specific direction and frictionally interlocked by the axial movement in the opposite direction. , A plurality of friction plates 96C for distributing the clutch are distributed and mounted, and a clutch spring 96D for urging the movable clutch housing 96A to move in a specific direction is provided. In other words, the movable clutch housing 96A is moved in the axial direction by the urging force of the clutch spring 96D in a specific direction, and the friction plate 96C is frictionally interlocked. Then, the movable clutch housing 96A is moved in the axial direction in the opposite direction against the urging force to release the frictional interlock, thereby disengaging the fixed clutch housing 96B from the movable clutch housing 96A and bringing the clutch disengaged state into effect. It is configured as follows.

In the transmission system to the driving rear wheel 2, a lower transmission side than the clutch 96, specifically, between the vertical transmission case portion 95 and the fixed clutch housing 96B, As shown in FIG. 7, as the operation bowl 98 for pressing the movable clutch housing 96A in the opposite direction via the bearing 97 moves in the opposite direction beyond the clutch disengagement position, the operation bowl 98 is pressed vertically by the operation bowl 98. The fixed clutch housing 96B is linked to the transmission case 95 so as to be linked with the fixed clutch housing 96B.
B, that is, a brake 99 for braking the driving rear wheel 2 in a state where the transmission is interrupted is provided.

100 rotates the operating bowl 98 from the clutch engaged position to the brake operating position by rotating the operation bowl 98 in a specific direction around the first longitudinal axis P1.
Is a clutch / brake operating shaft that reversibly presses and moves through the shaft. 102 moves axially in the opposite direction to move the movable clutch housing 96A from the clutch disengaged position to the clutch engaged position via a thrust collar 103. Transmission shaft 9 to reversibly press up to
Reference numeral 104 denotes a clutch sleeve which is slidably and rotatably fitted on the clutch sleeve 104. The cam 104 rotates the clutch sleeve 102 from the clutch engaged position to the clutch disengaged position by rotating in a specific direction around the second longitudinal axis P2. This is a clutch operation shaft that reversibly presses and moves through the shaft.

As shown in FIG. 9, the front wheel steering mechanism ST is configured to reversibly disengage the clutch 96 on the inside of the turn with the steering operation beyond the set angle from the straight traveling state of the driving front wheel 1. A clutch operating interlocking mechanism A for interlocking the left and right clutches 96, and the left and right clutches 96 are simultaneously disengaged with the depression operation of the brake pedal BP, and then the left and right brakes 99 are simultaneously operated. A brake operation interlocking mechanism B for interlocking the clutch 96 and the brake 99 with the brake pedal PB is provided.

The front wheel steering mechanism ST includes a steering handle 14, a handle shaft 14a, a torque generator 43, a pitman arm 111 driven to swing left and right by the torque generator 43, and left and right of the pitman arm 111. It comprises left and right drag links 119 for interlockingly connecting the knuckle arms 118 of the respective drive front wheels 1 to the pitman arm 111 so as to steer the drive front wheels 1 with the swing. The pitman arm 1
Reference numeral 11 is supported by the transmission case 9 so as to protrude downward.

The clutch operating interlocking mechanism A is shown in FIG.
As shown in FIG. 5, a relay link 113 interlockingly connected to the pitman arm 111 via a push-pull rod 112 so as to swing around the vertical axis Y along with the steering operation (left-right swing) of the pitman arm 111. And a relay link 113 for steering the pitman arm 111 to the left.
Swinging in one direction around the vertical axis Y with the swinging in one direction, the left clutch operating shaft 104 is pulled and rotated from the clutch engaged phase to the clutch disengaged phase via the rod 127. Simultaneously, the pitman arm 111 swings in the opposite direction around the vertical axis Y with the swinging of the relay link 113 in the opposite direction accompanying the rightward steering of the pitman arm 111, so that the right clutch operating shaft 104 is moved to the rod 127. A distributing link 114 is provided which can be switched between an interlocking state in which the relay link 113 is interlocked and a release state in which the interlocking is released so as to rotate from the clutch engagement phase to the clutch disengagement phase via The pitman arm 111 swings the pin pivot connection hole 115 with the pull rod 112 from the straight traveling posture to the set angle or more. Pitman arm 11 only when the
1 is transmitted to the push-pull rod 112, but is not transmitted to the swing smaller than the set angle.

As shown in FIGS. 11 and 12, the distribution link 114 is axially oriented with respect to an interlocking lever 126 which swings integrally with the relay link 113 via a shaft 125 supporting the relay link 113. The movable lever 126 can be moved far and near.
When the remote position is in the interlocked state, it is disengaged from the interlocking lever 126 to be released.

In the rice transplanter operating device, the clutch operating interlocking mechanism A is switched between the operating state and the operation releasing state, that is, the distribution link 114 is changed between the approaching interlocking position a1 and the separation releasing position a2. As shown in FIG. 5, FIG. 9, FIG. 11, and FIG. 12, the operation unit is a lever-like member that changes between an interlocking position A1 and a release position A2 by vertical swinging around a first horizontal axis x1. A spring 1 for arranging a state switching operation tool 117 below the seat 15 and for urging the distribution link 114 to move to the approach interlocking position a1
And a cam 121 for reversibly pressing and moving the distribution link 114 from the approach interlocking position a1 to the separation release position a2 against the urging force by swinging in one direction around the second horizontal axis x2. When the state switching operation tool 117 was operated to the release position A2, the cam 121 was swung to the release position in which the distribution link 114 was positioned at the separation release position a2, and the state switching operation tool 117 was operated to the operation position A1. When the cam 121 is the sorting link 1
A push-pull rod 122 for interlocking connection between the state switching operation tool 117 and the cam 121 is provided so as to swing to the interlocking posture in which the position 14 is positioned at the approach interlocking position a1.

The interlocking mechanism A for clutch operation causes the clutch 96 to be disengaged in accordance with the steering operation at a set angle or more from the straight traveling state of the drive front wheel 1, and the clutch 96
From the front wheel steering mechanism ST after the clutch is disengaged.
The cam 105, which is a mechanism for suppressing transmission of the operation force in the clutch disengagement direction to the clutch 6 and is a component of the clutch operation interlocking mechanism A, is shown in FIGS.
As shown in the figure, in the subsequent rotation in the specific direction after the clutch sleeve 102 is moved from the clutch engagement position to the clutch release position with the rotation in the specific direction, the clutch sleeve 102 moves beyond the clutch release position. Is formed so as to make the movement amount of the movement small. In other words, the clutch operating shaft 104 required to turn on and off the clutch 96
Is smaller than the rotation angle at which the clutch operation shaft 104 is operated due to the steering, and does not coincide with the operation rotation angle, but the difference is absorbed to prevent the clutch 96 from being forced. The cam 105 is formed integrally with the clutch operation shaft 104.

As shown in FIG. 5, the interlocking mechanism B for brake operation is interlocked with the brake pedal BP via a push / pull rod 200 so as to reversibly move forward with the depression operation of the brake pedal BP. Intermediate member 2
01 and the intermediate member 201 so that the two clutch / brake operating shafts 100 reversibly rotate from the clutch release phase to the brake operation phase through the clutch release phase as the intermediate member 201 moves forward. clutch·
Right and left rods 2 for interlocking connection with brake operation shaft 100
02 is provided.

[Another Embodiment] In the above embodiment, the rod 2 is pushed through the push-pull rod 200 and the intermediate member 201.
02 is linked to the brake pedal BP, but the rod 202 may be linked to the brake pedal BP directly.

In the above embodiment, the intermediate member 201
Is configured to be able to swing seesaw around a connection point with the push / pull rod 200. That is, when the brake pedal BP is offset to the right and the connection angles of the intermediate members 201 of the right and left rods 202 are different, when the brake pedal BP is depressed, one of the clutch / brake operating shafts is operated. 100 rotates to the end of the brake operation phase before the other clutch / brake operating shaft 100,
For example, when the intermediate member 201 is fixedly connected to the push / pull rod 200, or when the rod 202 is connected to the brake pedal B
When the clutch / brake operating shaft 100 rotates to the end of the brake operation phase, the brake pedal BP cannot be depressed any further, and the other clutch / brake operating shaft 100
Cannot be rotated to the end of the brake operation phase, and a difference in braking force occurs between the left and right brakes 99. On the other hand, in the case where the intermediate member 201 is configured to be capable of swinging the seesaw, the brake pedal is driven by the seesaw swing of the intermediate member 201 even after one clutch / brake operating shaft 100 rotates to the end of the brake operation phase. By allowing the BP depressing operation and rotating the other clutch / brake operating shaft 100 to the end of the brake operation phase, the braking forces of the left and right brakes 99 can be equalized. In short, the intermediate member 201
Is a means for absorbing the operation difference between the left and right brakes 99 due to the depression operation of the brake pedal BP.

In the above embodiment, as shown in FIG. 13, the left and right rods 202 are connected to the intermediate member 201 or the clutch / brake operating shaft 100 via the spring 203. In the drawing, the intermediate member 201 is connected via a spring 203. In this case as well, the operation of depressing the brake pedal BP after the rotation of one clutch / brake operating shaft 100 to the end of the brake operation phase is permitted by the deformation of the spring 203, and the other clutch / brake operation is performed. The shaft 100 can also be rotated to the end of the brake operation phase to equalize the braking forces of the left and right brakes 99. That is, the spring 203 constitutes an absorbing unit that absorbs the operation difference between the left and right brakes 99 due to the depression operation of the brake pedal BP.

In the above embodiment, the clutch operation interlocking mechanism A has been described as being switchable between an operating state and an operation releasing state. However, the clutch operation interlocking mechanism A is not a switchable type, and is always switched. It may be in the operating state.

In the above embodiment, as the clutch operating interlocking mechanism A, the clutch 96 is disengaged in accordance with the steering operation beyond the set angle from the straight traveling state of the drive front wheel 1, and the front wheel after the clutch 96 is disengaged is operated. Steering mechanism S
Although the mechanism for suppressing the transmission of the operation force in the clutch disengagement direction from T to the clutch 96 has been described, the clutch operating interlocking mechanism A operates the clutch 96 in accordance with the steering operation at a set angle or more from the straight traveling state of the driving front wheel 1. It may be a mechanism that performs the disengagement operation and that prevents the transmission of the operation force in the clutch disengagement direction from the front wheel steering mechanism ST to the clutch 96 after the clutch 96 has been disengaged. Specifically, the cam 105
After the clutch sleeve 102 is moved from the clutch engaged position to the clutch disengaged position with the rotation in the specific direction, the clutch sleeve 1
The amount of movement beyond the clutch disengagement position of 02 is set to zero.

[Brief description of the drawings]

FIG. 1 is a side view

FIG. 2 is a plan view

FIG. 3 is a side view of a main part.

FIG. 4 is a plan view of a main part.

FIG. 5 is an operation system diagram

FIG. 6 is a longitudinal sectional view of a main part of a rear axle case.

FIG. 7 is an enlarged longitudinal sectional view of a main part of a rear axle case.

FIG. 8 is a sectional view of a main part showing a clutch engagement / disengagement operation state;

FIG. 9 is a side view of a main part.

FIG. 10 is a plan view of a main part of an interlocking mechanism for clutch operation.

FIG. 11 is a front view of a main part of an interlocking mechanism for clutch operation.

FIG. 12 is an operation diagram showing a state switching of the clutch operating interlocking mechanism.

FIG. 13 is an operation system diagram showing another embodiment.

[Explanation of symbols]

 Reference Signs List 1 front wheel 2 drive rear wheel 96 clutch 99 brake ST front wheel steering mechanism A clutch operating interlock mechanism BP brake pedal B brake operating interlock mechanism

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2B043 AA04 AB03 AB07 BA02 BB06 DA06 DB07 3D036 GA16 GB05 GD07 GH20 GJ12 3D043 AA03 AB11 EA18 EA44 EA45 EB02 EB12 3D052 AA02 AA02 BB08 DD03 EE02 EJ17 JJ01 JJ01 JJ01 JJ03 JJ02 EJ02 JJ22 JJ31 JJ35

Claims (3)

[Claims] 1. A clutch for intermittently transmitting power to a driving rear wheel and a brake for braking a driving rear wheel in each of the transmission systems to the left and right driving rear wheels, wherein the clutch is located on the transmission upper side than the brake. Interlocking with the front wheel steering mechanism to interlock the clutch with the front wheel steering mechanism so that the clutch inside the turning is reversibly disengaged with the steering operation beyond the set angle from the straight running state of the steering front wheel A brake is provided in which a clutch and a brake are interlocked such that a mechanism is provided, a brake pedal is provided, and the two clutches are simultaneously disengaged and operated simultaneously with the depression operation of the brake pedal, and then both brakes are simultaneously operated. Paddy field working machine with an interlocking mechanism for operation. 2. A clutch for intermittently transmitting power to the rear driving wheel and a brake for braking the rear driving wheel, each of the transmission systems for the left and right driving rear wheels, wherein the clutch is located on the upper transmission side than the brake. Interlocking with the front wheel steering mechanism to interlock the clutch with the front wheel steering mechanism so that the clutch inside the turning is reversibly disengaged with the steering operation beyond the set angle from the straight running state of the steering front wheel A clutch mechanism is provided to operate the clutch as an interlocking mechanism for the clutch operation. A paddy working machine provided with a mechanism for preventing or suppressing transmission of directional operation force. 3. The paddy working machine according to claim 1, wherein the interlocking mechanism for brake operation is provided with an absorbing means for absorbing a difference in operation between the left and right brakes caused by a depression operation of a brake pedal.