JP2001088731A - Rice paddy field working machine of riding type - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure an easy turning without damaging a rice paddy field while attaining a compact structure of running system and an improved operability in stopping a machine body. SOLUTION: A drive side boss member 96A supporting a drive side friction board of a side clutch 96 is mounted on the right and left parts of a lateral transmission shaft 83 equipped with a rear transmission case 10, and ON/OFF operation of the side clutch 96 is performed by shifting the member 96A. To only the member 96A a rotation side friction board 31 constituting a brake for stopping a machine body 30 is mounted. A fixed side friction board 32 constituting the brake 30 is engagewise supported so as not to be rotatable relatively on the case 10. In linkage with pressing-down operation for a pedal the board 31 and the board 32 are brought into pressure contact with each other to brake the shaft 93.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a riding paddy working machine configured to transmit shifted power to left and right front wheels that can be steered and right and left rear wheels that cannot be steered.

[0002]

2. Description of the Related Art In a riding rice transplanter, which is a representative of a riding type paddy working machine, right and left front wheels are driven via a differential mechanism, and right and left rear wheels are driven at a constant speed via side clutches and brakes. Wheel drive forms are frequently used. In addition, as the operation structure, a main clutch pedal for intermittently operating the transmission of power from the engine to the traveling transmission is provided on the left side of the foot of the riding section, and a side clutch is provided on the right side of the foot of the riding section. -A pair of left and right side clutch brake pedals that operate the brakes independently of each other are arranged in parallel.

In the above arrangement, the main clutch pedal is depressed to release the main clutch, and the left and right side clutch brake pedals are simultaneously depressed to release the left and right side clutches to brake the left and right side brakes. By doing so, the aircraft can be stopped,
In addition to steering the front wheels, depressing only one of the side clutch brake pedals on the inside of the turn, disengaging the side clutch on the inside of the turn and braking the side brake on the inside of the turn, You can make a small turn.

By the way, when the left and right rear wheels of the working machine entering the paddy field are driven via the differential mechanism in the same manner as the tractor, the driving speed of the left and right rear wheels is automatically changed at the time of turning, so that the vehicle can smoothly turn. On the other hand, since the left and right rotation speed changes according to the load, the straightness decreases in paddy fields where the tillage has irregularities and the ground load of the left and right rear wheels is easily changed, Aircraft control becomes difficult. For this reason, paddy working machines such as rice transplanters, in which straight running performance is regarded as important, employ the rear wheel side clutch / brake system.

[0005]

The riding paddy working machine provided with the traveling system having the above-mentioned structure which is excellent in straight traveling performance is suitable for working traveling in the paddy field, but has a problem in turning property at the ridge. was there. In other words, when the aircraft makes a large U-turn around the ridge, when the aircraft is turned by operating the side clutch brake pedal, the rear wheel that is not rotating is dragged around because the rear wheel inside the turn is fixed by the side brake. As a result, the field is greatly damaged, and a problem that the running load increases is likely to occur. In particular, such a tendency became stronger in deep fields.

In order to stop the machine, the main clutch pedal provided on the left side of the foot and the left and right side clutch brake pedals provided on the right side of the foot are depressed. However, three pedal depression operations are required. Therefore, the operation was troublesome. In particular, since the left and right side clutch brake pedals must be depressed at the same time, when traveling on roads, etc., a mechanism for connecting both side clutch brake pedals with connecting brackets is required separately. Therefore, the switching operation of the connection fitting is required in accordance with the above, which is a troublesome operation.

SUMMARY OF THE INVENTION The present invention has been made in view of such a situation. The present invention is capable of simplifying the structure of a traveling system, making it possible to turn lightly without ruining a field, and also to turn the airframe. An object of the present invention is to provide a riding type paddy working machine excellent in operability when stopping the machine.

[0008]

Means for Solving the Problems [Structure, operation and effect of the invention according to claim 1]

(Structure) The invention according to claim 1 is a riding type paddy working machine configured to transmit the shifted power to the steerable left and right front wheels and the unsteerable left and right rear wheels.
The rear transmission case is equipped with a lateral transmission shaft for transmission to the left and right rear wheels, and a friction type side clutch for each of the left and right rear wheels is mounted on the lateral transmission shaft. A drive-side boss member for externally supporting the drive-side friction plates of the left and right side clutches is mounted so as to be shiftable and integrally rotatable with the lateral transmission shaft, and each of the drive-side boss members is shifted to a corresponding side clutch. A friction plate on the rotating side constituting a brake for stopping the machine is mounted so as to be integrally rotatable with the driving side boss member only on the driving side boss member of one of the side clutches, and the brake is mounted. The fixed-side friction plate is supported by the rear transmission case so as to be non-rotatably engaged with the rear transmission case, and rotates in conjunction with the depression operation of the body stopping pedal provided in the boarding operation unit. It said friction plate and pressed against the said friction plate of the stationary side, characterized in that are configured to brake the lateral transmission shaft.

(Operation) According to the above-described configuration, when changing the direction of the aircraft at a ridge or the like, the front wheels are largely steered, and the side clutch of only one of the rear wheels on the inside of the turn is disengaged. According to this, the left and right front wheels and the turning outer rear wheel
The body is turned by the driving of the wheels, and at this time, the rear wheel inside the turning is idle, so that the body follows and rotates with the turning movement of the body without difficulty.

Further, when the vehicle is stopped without disengaging the side clutch and the vehicle is depressed, the lateral transmission shaft, which is the transmission shaft connected to the traveling system, is braked, whereby not only the rear wheels but also the front wheels are braked. The aircraft can be stopped by braking and four-wheel braking. When the front wheels are largely steered and one of the side clutches is disengaged and the vehicle is turning slightly, depressing the fuselage stop pedal will apply braking to the three wheels except the rear wheel inside the turn to stop the fuselage. be able to.

Further, in forming the brake for stopping the machine body, a drive-side boss member forming one side clutch is also used as a support member of a friction plate forming a friction type brake.

(Effects) According to the first aspect of the present invention, the front wheel is steered and the vehicle is turned with only the side clutch on the inside of the turn being disengaged, thereby turning using the side clutch / brake. The problem seen in the configuration, that is, a phenomenon in which the rear wheel on the inside of the turn is dragged in a fixed state and the field is roughened or the running load is increased can be suppressed, and the smooth turning of the body can be performed lightly. .

In addition, since the friction plate on the rotating side of the brake is supported by the driving boss member that supports the driving friction plate constituting the side clutch, the transverse transmission shaft in the rear transmission case can be used while also using parts. This makes it possible to obtain a structure that applies braking to the vehicle, thereby improving traveling and turning performance while simplifying the structure.

[Structure, operation and effect of the invention according to claim 2]

(Structure) According to a second aspect of the present invention, in the first aspect of the present invention, a main transmission shaft for outputting shifting power from a transmission case at a front portion of the fuselage to the rear transmission case, and the lateral transmission shaft are provided. In the rear transmission case, the bevel gear is interlocked with the rear transmission case, and a driven bevel gear provided on the lateral transmission shaft is disposed on the side opposite to the brake installation side with respect to an input portion from the main transmission shaft.

(Operation / Effect) According to the above configuration, the weight on the side where the brake for stopping the aircraft is installed increases,
Since the driven bevel gear on the opposite side is present, the collapse of the right and left weight balance of the rear transmission case is alleviated, and it is possible to suppress the deterioration of the airframe balance while disposing the stop brake in one side.

[Structure, operation and effect of the invention according to claim 3]

(Structure) According to a third aspect of the present invention, in the first or the second aspect of the present invention, the output from the outside portion of the side clutch is transmitted to the left and right ends of the rear transmission case via a reduction gear mechanism. A reduction gear case portion for transmitting to the wheels, the reduction gear mechanism is constituted by two reduction gear pairs for reducing the speed in two stages, and a rear gear pair is disposed on the inner side of the fuselage than the preceding gear pair to form a side clutch. They are arranged in duplicate.

(Operation / Effect) According to the above configuration, the side clutch and the reduction gear mechanism for performing two-stage reduction can be inserted into each other and arranged compactly in the axial direction. As a result, as a result, the reduction The gear case portion can be made small in width and light in weight.

[0021]

1 and 2 show a riding type rice transplanter of a five-row type as an example of a paddy field working machine. This riding type rice transplanter has a riding type self-propelled body 3 having a pair of steerable left and right front wheels 1 and a pair of unsteerable left and right rear wheels 2.
At the rear, a five-row planting seedling planting device 4 is connected via a four-link mechanism 5 driven by a lifting cylinder 6 so as to be able to move up and down freely, and a 5-row planting fertilizer 7 is provided at the rear of the body. It has a structure.

A transmission case 9 provided with a front axle case 9a for supporting the front wheel 1 is fixedly connected to a front portion of the body frame 8 of the self-propelled body 3, and a rear portion of the body frame 8 is Rear transmission case 1 that supports rear wheel 2
0 is supported in a freely rolling manner. In addition, an engine 11 having a lateral output shaft 11a is mounted via a vibration-isolating rubber 12 at a position near the front of the transmission case 9, and a boarding operation unit 13 is provided in a state located behind the engine 11. ing. The boarding operation unit 13 includes:
Steering handle 1 for steering front wheel 1
4, a driving seat 15, a driving step 24, and the like.

The seedling planting apparatus 4 mounts five rows of seedlings and reciprocates with a set stroke in the left-right direction, and cuts out seedlings one by one from the lower end of the seedling nest 16. It comprises five sets of rotary planting mechanisms 17 for planting in the field, three leveling floats 18 for leveling the planting points, etc., and reserves seedlings for replenishing the seedling rest 16. Stands 49 for spare seedlings to be placed and accommodated in a plurality of stages are provided on the left and right sides of the front of the fuselage.

The fertilizer application device 7 is mounted on the self-propelled body 3 between the driver's seat 15 and the seedling planting device 4.
A fertilizer hopper 19 for storing powdered and granular fertilizer, and a feeding mechanism 2 for feeding the fertilizer in the fertilizer hopper 19 by a set amount.
0, an electric fan 23 that pneumatically conveys the fed fertilizer through a supply hose 22 to a groove generator 21 provided on the leveling float 18 of the seedling planting device 4.

As shown in FIGS. 3 and 4, on the left side of the transmission case 9, an output shaft 11 of the engine 11 is provided.
and a hydrostatic continuously variable transmission (HST) 41 as a main transmission having a lateral input shaft 41a interlocked with the transmission shaft a through a belt transmission device 40, and transmits its output into the transmission case 9 by a lateral shaft. And the input shaft 4
1a and the output shaft 41b are connected in a state where they are arranged in front and rear.

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

The input shaft 4 of the hydrostatic continuously variable transmission 41
1a extends rightward through the front of the transmission case 9. A main shift lever 46 for operating the hydrostatic continuously variable transmission 41 is disposed on the left side of the steering handle 14.
The forward speed can be changed by a swing operation from neutral to forward, and the reverse speed can be changed by a swing operation from neutral to backward.

On the right side of the transmission case 9, as shown in FIG.
Hydraulic pump 42 driven by the extended end of the input shaft 41a
3 and 4, a torque generator 43 constituting a hydraulic power steering device interlocked with a handle shaft 14a of the steering handle 14, as shown in FIGS.
A control valve 44 for controlling the lifting / lowering cylinder 6 for raising / lowering the working device is attached.

The transmission case 9 is also used as a hydraulic oil tank. Lubricating oil in the transmission case 9 is taken out as hydraulic oil through an oil filter 45 mounted on the right side surface of the transmission case 9 and is subjected to a hydrostatic operation. Supply to the continuously variable transmission 41 and the hydraulic pump 42,
The pressure oil from the hydraulic pump 42 is supplied to the torque generator 43
And then to the lift cylinder 6 through the control valve 44. The drain oil of the hydrostatic continuously variable transmission 41 is transmitted to the transmission case 9.
Is returned to the front axle case 9a communicating with the control valve 44.
Drain oil is directly returned to the mission case 9.

As shown in FIGS. 5 and 6, in the transmission case 9, a main clutch 50 for intermittently transmitting the output from the hydrostatic continuously variable transmission 41, and an output from the main clutch 50. Transmission 51 for shifting gears between high and low
And a differential mechanism 52 for transmitting the output from the auxiliary transmission 51 to the left and right front wheels 1 and transmitting only the forward rotation power of the power branched from the traveling transmission system to the seedling planting apparatus 4. A one-way clutch 53, a planting speed change mechanism 54 for changing the power between the plants, and a planting clutch 55 for intermittently transmitting power to the seedling planting device 4 are provided.

The main clutch 50 is of a multi-plate friction type, and has an input shaft 5 connected to an output shaft 41b of the hydrostatic continuously variable transmission 41 via a coupling 56.
7, a drive-side boss member 58 is integrally rotatably connected thereto, and a driven-side drum 60 covering the drive-side boss member 58 is attached to a clutch output shaft 59 loosely fitted to the input shaft 57 so as to be shiftable. It is connected and supported so that it can rotate integrally,
The clutch output shaft 59 and the driven drum 60 are shifted with respect to the driving boss member 58 so that the driving boss member 58
By pressing or releasing the friction plates 61 interposed between the driving side boss member 58 and the driven side drum 60,
The clutch output shaft 59 and the driven drum 60 are always urged by the spring 62 in the friction plate pressing direction (clutch-engaging direction). I have.

The main clutch 50 can be turned on and off only by pedal operation. That is, the vehicle body stopping pedal 25 provided at the right foot of the step 24 in the boarding operation unit 13 and the penetrating mounting on the upper surface of the transmission case 9 so as to be rotatable around a vertical axis P orthogonal to the input shaft 57. And a pivot arm 27 is attached to a pedal shaft 26 that pivots integrally with the body stopping pedal 25. The pivot arm 27 and the clutch operation shaft 63 are provided outside the case. The passive arm 63a provided on the protruding portion has a structure in which the passive arm 63a is interlocked and connected by the rod 28, and the clutch operating shaft 63 is rotated in the forward and reverse directions with the depression operation and the depression release operation of the body stopping pedal 25. It has become.

An eccentric cam 63b having a semicircular cross section formed by cutting off a part of the peripheral surface is formed at the tip of the clutch operating shaft 63 in the case.
b faces the end face of the clutch output shaft 59.
In a normal state where the vehicle stop pedal 25 is not depressed, as shown in FIG. 5, the eccentric cam 63b is in a position in which the pressing on the clutch output shaft 59 is released, thereby bringing the main clutch 50 into the "engaged" state. It is. When the vehicle stop pedal 25 is depressed, the edge of the eccentric cam 63b is displaced and pressed against the end face of the clutch output shaft 59, and the clutch output shaft 59 is moved against the bias by the spring 62, and When the drum 60 is displaced rightward in the drawing, the main clutch 50 is switched to the “disengaged” state. In this clutch disengaged state,
The friction between the edge of the eccentric cam 63b and the end face of the clutch output shaft 59 gives resistance to the rotation of the clutch output shaft 59, and prevents the clutch output shaft 59 from rotating together with the input shaft 57. I have.

The auxiliary transmission 51 is of a gear shift type, and a high-speed large-diameter transmission gear 65 and a low-speed small-diameter transmission gear 66 are integrally rotated on a transmission input shaft 64. The high-speed position in which the small-diameter gear portion 68 meshes with the large-diameter transmission gear 65 and the low-speed position in which the large-diameter gear portion 69 meshes and interlocks with the small-diameter transmission gear 66. A shift gear 70 that can freely shift to a neutral position where the gears do not engage with each other is mounted so as to rotate integrally. A small-diameter output gear 71 that meshes with the large-diameter transmission gear 65 and transmits the power in a decelerated manner is mounted on the clutch output shaft 59 so as to rotate integrally therewith.
Is linked to deceleration. A sub-transmission lever 47 for operating the sub-transmission 51 is arranged on the left side of the driver's seat 15.

The differential mechanism 52 is configured to be differentially lockable. That is, a shift member 74 is attached to one of the differential shafts 72 extending left and right so as to be rotatable integrally with the differential shaft 72 and shiftable. As shown in FIG. The state in which the shift member 74 is separated from the state 73 is a normal differential lock release state, and the shift member 74 is shifted rightward in the drawing and meshes with the end face of the differential case 73 to provide a differential lock state. The differential lock operation means for switching the differential mechanism 52 between the differential lock state and the differential lock release state includes a spring (not shown) that urges the shift member 74 to the differential lock release position and a riding operation unit 13.
The differential lock pedal 48 and the shift member 74, which are provided at the left rear portion of the foot of the vehicle, are linked to each other,
By releasing the foot from the differential lock pedal 48 during normal traveling, the differential lock release state is maintained, the aircraft is taken in and out of the field, and the aircraft is loaded and unloaded on the carrier of the transport vehicle,
In such a case, the differential lock pedal 48 is depressed with the heel of the left foot to provide a differential lock state, and the left and right front wheels 1 can be driven at a constant speed.

The differential case 73 of the differential mechanism 52
An input gear 76 meshed with a shift output gear 75 spline-connected to the shift output shaft 67, and an output gear 79 is mounted on a gear 78 integrally formed with the main transmission shaft 77 for transmission to the rear wheel 2. I have.

The one-way clutch 53 uses the transmission input shaft 64 as a branch point from the traveling transmission system to the planting transmission system.
It is provided so that only the forward rotation of the rotation of the speed change input shaft 64 is transmitted to the planting transmission system.

The planting transmission mechanism 54 is mounted on the transmission output shaft 67 so as to be freely rotatable only relative to the transmission output shaft 67, and has a diameter relative to a cylindrical shaft 82 which is interlocked with an output gear 80 of the one-way clutch 53 via a gear 81. Drive gears 83 having different driving gears
Are mounted so as to rotate integrally with each other, and are linked to the planting clutch 55 via bevel gears 84 and 85, so that the speed change output shaft 8 is planted.
6, a group of driven gears 87 which are always engaged with and linked to each of the drive gears 83 are rotatably mounted relative to each other, and the driven gears 87 are engaged with engagement recesses 88 formed in the center holes of the driven gears 87 so that the driven gears 87 are engaged. A transmission ball 89 interlockingly connected to the planted transmission output shaft 86 is provided so as to rotate integrally with the planted transmission output shaft 86, and an operating shaft 90 is provided for selectively engaging the transmission ball 89 with the engagement recess 88. It is a structure that was given. That is, by alternately linking the driven gear 87 to the planted transmission output shaft 86, the driven gear 87 used for transmission is changed, and a plurality of gears (in the example, six gears) are shifted. Have been.

The rear transmission case 10 for driving rear wheels is shown in FIG.
As shown in FIG. 9, a horizontal transmission case portion 10A is supported by the body frame 8 so as to be freely rotatable within a predetermined range around a longitudinal axis X, and a speed reduction case portion 10B connected to both left and right ends thereof. Have been. Inside the horizontal transmission case portion 10A, there is provided a horizontal transmission shaft 93 for distributing the power from the main transmission shaft 77 extending rearward from the transmission case 8 to the left and right, and the horizontal transmission shaft 93 and the main transmission shaft 77 are provided. Are linked to each other via bevel gears 91 and 92. Further, each deceleration case portion 10B has an axle 2A for supporting the rear wheel 2 and the lateral transmission shaft 93.
And a reduction gear mechanism 94 for reducing the speed of the axle 2A. Here, the driven side 92 provided on the lateral transmission shaft 93 is installed on the opposite side of the friction type brake 30 from the input portion from the main transmission shaft 77,

A transmission system to the rear wheel 2, more specifically, between each end of the lateral transmission shaft 93 and each of the reduction gear mechanisms 94, a multi-plate type for separately transmitting the transmission to each rear wheel 2. Side clutch 96 is interposed. These side clutches 96 are provided with a boss member 96A that is spline-fitted to the lateral transmission shaft 93, is integrally rotated, and is movable in the axial direction, and a driven drum 96B that is interlocked with the reduction gear mechanism 94. A plurality of friction plates 96C, which are pressed against each other by the outward movement of the fuselage to engage in friction (clutch engagement) and release the frictional engagement (clutch disengagement) by moving the boss member 96A inwardly to the fuselage, include A clutch spring 96 </ b> D that is distributed and mounted on the driven drum 96 </ b> A and the driven drum 96 </ b> B and urges the boss member 96 </ b> A toward the clutch engagement side is externally mounted on the lateral transmission shaft 93.

The reduction gear mechanism 94 is provided on the lateral outer side of the driven drum 96B of the side clutch 96 and has a small diameter first gear G1 which rotates integrally with the driven drum 96B.
A large-diameter second gear G2 meshing with the second gear G2, a small-diameter wide third gear G3 coaxial with the second gear G2 and integrally rotating therewith;
The large-diameter and wide fourth gear G4 connected to the axle 2A is configured to reduce the speed in two stages. A gear pair of the third gear G3 and the fourth gear G4 is provided inside the body and a side gear is provided. The lower portion of the clutch 96 is suppressed from widening the speed reduction case 95 laterally outward.

As shown in FIG. 8, an airframe stop brake 30 is provided between the right deceleration case portion 10B and the boss member 96A. This machine stop brake 30
The boss member 96A and the boss member 96A are pressed against each other by pressing the friction plate 31 fitted to the outer periphery of the boss member 96A with the spline and the friction plate 32 engaged with the inner periphery of the deceleration case portion 10B and stopped from rotating. It is configured to brake the transverse transmission shaft 93 that rotates integrally, and the cup-shaped operation member 33 loosely fitted to the boss member 96A is moved laterally outward (rightward in FIG. 8) by friction. The plates 31, 32 are pressed against each other.

The machine stop brake 30 is operated by a brake operation shaft 34 which is rotatably mounted on the upper surface of the deceleration case 10B around the longitudinal axis P1. In other words, the shift fork 35 is mounted on the portion of the brake operation shaft 34 that protrudes into the case, and the shift fork 35 is provided to face the end surface of the operation member 33. By shifting the operation member 33 via the shift fork 35,
The boss member 96A can be braked.

Then, as shown in FIG. 7, an operation arm 34a provided on the outside of the case of the brake operation shaft 34 is provided.
Is linked to the body stop pedal 25 via a linkage rod 36. With the depression operation of the body stop pedal 25, the linkage rod 36 is pulled forward and displaced, the body stop brake 30 is braked, and the body stops. Pedal 25
When the brake pedal is released to return to the original posture, the braking of the machine stop brake 30 is released. Here, since the machine stop brake 30 is also linked to the main clutch 50 as described above, it functions as a main clutch / brake pedal.
The main clutch 50 is firstly disengaged by a stepping operation, and braking is applied by a subsequent stepping operation.

The link rod 36 is provided with a turn buckle 36a.
The operation timing of the machine stop brake 30 with respect to the main clutch 50 can be adjusted by adjusting the expansion and contraction to “a”.

The operation structure of the side clutch 96 is configured as follows. In other words, the clutch operating sleeve 102 is disposed on the lateral transmission shaft 93 with the end face of the boss member 96A abutted through the thrust collar 103.
Is freely slidably fitted, and the reduction case 1
A clutch operation shaft 104 is rotatably mounted around the longitudinal axis P2 on the upper surface of the clutch operation shaft 0A, and an eccentric cam 105 formed at a protruding end of the clutch operation shaft 104 in the case faces an end surface of the clutch operation sleeve 102. The side clutch 96 is arranged by the rotation operation of the clutch operation shaft 104.
Is turned on and off.

The left and right side clutches 96
Only the inside of the turning operation is automatically turned off based on the body steering operation, and the side clutch automatic operation mechanism 106 is configured as follows. That is, as shown in FIG. 7, the pitman arm 111, which is driven to swing left and right by the torque generator 43 constituting the power steering device, and the knuckle arm 118 of each front wheel 1 are linked and connected via the tie rod 119. A steering link mechanism 110 is configured, and an operation fitting 111a connected to the pitman arm 111 and a relay arm 113 provided at a lower portion near the front-rear middle of the fuselage so as to be swingable about a vertical axis Y are pushed and pulled by a rod. The left and right ends of the balance arm 115 connected to the upper end of the fulcrum shaft 114 of the relay arm 113 and the operation arms 104a connected to the outer protrusions of the left and right clutch operation shafts 104 are connected to the rod 1 by the rod 1 respectively.
And 16 are interlockingly connected. The rod 116
The rearward end of the rod 116 and the operating arm 10 are moved so that the operating arm 104a is swung by the forward displacement of the rod and the operating arm 104a is not swung by the rearward displacement of the rod 116.
4a is linked with a long hole pin.

Here, a push-pull rod 11 formed on an operation fitting 111a connected to the pitman arm 111 is used.
2 is formed as an elongated hole along the swinging direction of the operation fitting 111a, and only when the pitman arm 111 swings from the straight running posture to a set angle (for example, 30 °) or more, the pitman arm 111 is rotated. Is transmitted to the push / pull rod 112, but the length of the link hole 117 is set so as not to transmit the swing smaller than the set angle.

Therefore, when the left and right front wheels 1 are steered more than a set angle in order to turn the body largely, the swing of the pitman arm 111 is transmitted to the balance arm 115 via the relay arm 113, and the pulling operation is performed forward. Only one of the side clutches 96 linked to the rod 116 is disengaged. That is, the side clutch 96 on the inside of the turn.
Only the left and right front wheels and the turning outer rear wheel 2
The wheel is turned by the wheel drive, and the rear inner wheel 2 in the idle state rotates following the ground in accordance with the turning movement of the aircraft, and rotates with the rear wheel 2 inside the turning without unduly damaging the field. Is performed.

[Brief description of the drawings]

FIG. 1 is an overall side view of a rice transplanter.

FIG. 2 is an overall plan view of the rice transplanter.

FIG. 3 is a side view of a front part of the aircraft.

FIG. 4 is a plan view of a front part of the fuselage.

FIG. 5 is a sectional view showing a part of a transmission mechanism in a transmission case.

FIG. 6 is a sectional view showing a part of a transmission mechanism in a transmission case.

FIG. 7 is an operation system diagram

FIG. 8 is a longitudinal rear view showing a right portion of the rear transmission case.

FIG. 9 is a longitudinal rear view showing the left side portion of the rear transmission case.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 front wheel 2 rear wheel 9 transmission case 10 rear transmission case 10B reduction gear case section 13 riding operation section 25 body stopping pedal 30 brake 31 friction plate 32 friction plate 77 main transmission shaft 91 bevel gear 92 bevel gear 93 lateral transmission shaft 94 reduction gear mechanism 96 Side clutch

Claims (3)

[Claims] 1. A riding paddy working machine configured to transmit a shifted power to left and right front wheels that can be steered and left and right wheels that cannot be steered, wherein a rear transmission case transmits power to the left and right rear wheels. In addition to the provision of a lateral transmission shaft for the vehicle, and the provision of a friction-type side clutch for each of the left and right rear wheels on the lateral transmission shaft, the driving friction of the left and right side clutches on the left and right of the lateral transmission shaft. A drive-side boss member for externally supporting the plate is mounted so as to be shiftable and rotatable integrally with the lateral transmission shaft, and each drive-side boss member is shifted to operate a corresponding side clutch to be turned on and off. Only on the drive side boss member of the clutch, a rotating friction plate constituting a brake for stopping the machine is mounted so as to be integrally rotatable with the drive side boss member, and the brake constituting the brake is fixed. The friction plate on the side is engaged with the rear transmission case so as to be relatively non-rotatable, and the friction plate on the rotating side and the friction plate on the fixed side are interlocked with the depression operation of the body stopping pedal provided in the boarding operation unit. , Which is configured to brake the lateral transmission shaft by pressing against the paddle. 2. A main transmission shaft for outputting shifting power from a transmission case at a front portion of the fuselage to the rear transmission case;
The lateral transmission shaft is interlocked with a bevel gear in the rear transmission case, and a driven bevel gear provided on the lateral transmission shaft is arranged on the side opposite to the brake installation side with respect to an input portion from the main transmission shaft. Claim 1
The riding paddy working machine described. 3. A reduction gear case portion for transmitting an output from an outside portion of the side clutch to a rear wheel via a reduction gear mechanism at both left and right end portions of the rear transmission case, wherein the reduction gear mechanism is provided in two stages. The riding paddy working machine according to claim 1 or 2, comprising two reduction gear pairs for decelerating, and a rear gear pair disposed inside the body of the front gear pair and overlapped with a side clutch.