JP2000270627A - Steering unit for paddty field working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compact the size of a torque generator. SOLUTION: A torque generator 43 for the hydraulic power steering is linked to the upper face of the transmission case 9 arranged above the front steering wheel 1, the vertical rotary shaft that is synchronously connected to this torque generator 43 is synchronously linked to the pitman arm shaft 92a. In addition, an intermediate joint 99 that is equipped with the interlocking part that is relatively swingable and torque-transmittably fitted to the swing motion- outputting shaft 43b of the torque generator 43 and with the output unit to the vertical rotary shaft 95 is supported by the transmission case 9 rotatably around the vertical shaft axis P.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission case in which a torque generator for hydraulic power steering is connected to an upper surface of a transmission case disposed above a front wheel for steering, and a transmission shaft and a transmission are connected to a longitudinal rotation shaft interlocked with the torque generator. The present invention relates to a steering device for a paddy field working machine such as a rice transplanter, which is linked to a pitman arm shaft supported on a case.

[0002]

2. Description of the Related Art Conventionally, a sliding motion of a swing output shaft of a torque generator is converted into a rotation around one axis and transmitted to a vertical rotation shaft. An intermediate transmission member linked to the transmission state is supported by the torque generator so as to be rotatable around the vertical axis, so that the intermediate transmission member is concentric with the vertical rotation shaft when the torque generator is mounted on the transmission case. The vertical rotation shaft was interlocked and connected to the torque generator by being positioned and linked.

[0003]

However, according to the above-mentioned conventional technique, since the intermediate transmission member is incorporated in the torque generator, the torque generator is accordingly bulky, and the amount of projection upward from the transmission case is increased. Was becoming bigger. This means that, for example, the torque generator is arranged so that its input shaft is substantially perpendicular to the upper surface of the transmission case, and the handle shaft installed in the rearward inclined posture and the input shaft are connected via a universal joint. When the torque generator is operated in conjunction with the operation of the steering handle, the upward projection of the torque generator becomes large as described above, so that the vertical distance between the input shaft and the steering handle is reduced, and the torque generator is freely operated. The input shaft and the handle shaft interlocked via the joint are largely bent, and as a result, the smoothness of transmission of the handle operation force to the input shaft is reduced. That is, the steering operability is reduced.

An object of the present invention is to reduce the size of a torque generator.

[0005]

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

[Features] A torque generator for hydraulic power steering is connected to the upper surface of a transmission case arranged above the front wheels for steering, and a pitman supported on the transmission case and a vertically rotating shaft interlocked with the torque generator. What is claimed is: 1. A steering device for a paddy working machine having an arm shaft interlockingly connected thereto, wherein said vertically rotating shaft is interlockingly connected to said torque generator, and is relatively swayable to a torque output shaft of the torque generator and is in a torque transmitting state. An intermediate joint member having an interlocking portion that is fitted to and interlocked with the shaft and an output portion to the vertical rotation shaft is supported by the transmission case so as to be rotatable around the vertical axis.

[Operation] An intermediate joint member that is interlocked with the swing output shaft of the torque generator and that is interlocked with the longitudinally rotating shaft while being interlocked with the torque transmission state, that is, the intermediate transmission described in the above prior art. The equivalent of the members is rotatably supported on the transmission case around the vertical axis, and the torque generator and the vertical rotation shaft are interlockingly connected. It can be made compact and the amount of protrusion upward from the transmission case can be reduced.

[Effect] Accordingly, the torque generator is arranged so that its input shaft is substantially perpendicular to the upper surface of the transmission case, and the handle shaft and the input shaft installed in the rearward inclined posture are connected via a universal joint. When the torque generator is operated in accordance with the operation of the steering wheel, the vertical operation between the steering handle and the input shaft can be increased to allow the steering operation to be performed smoothly.

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

[Features] In the present invention according to claim 1, the torque generator is arranged such that its input shaft is substantially perpendicular to the upper surface of the transmission case,
The input shaft and the handle shaft installed in the rearward inclined posture are interlocked via a universal joint.

[Operation] In view of the above points, since the input shaft of the torque generator is provided in a posture substantially perpendicular to the upper surface of the transmission case, for example, the input shaft is extended on the extension of the handle shaft in the rearward inclined posture. Compared to the case where the torque generator is installed in the rearward inclined posture so that
Since the mounting portion of the torque generator to the transmission case can be positioned rearward, the front end of the transmission case can be positioned rearward and the transmission case can be downsized in the front-rear direction.

[Effect] Therefore, the degree of refraction between the input shaft and the handle shaft can be reduced, and the transmission of the operating force from the handle shaft to the input shaft can be performed smoothly. It can be made compact.

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

[Features] In the present invention according to the first and second aspects, the hydrostatic stepless transmission is provided on one lateral side of the transmission case, and the lateral input shaft and the output shaft into the transmission case are front and rear. , And a vertical rotation axis is arranged in a state between the input shaft and the output shaft in a side view.

[Operation] Since the hydrostatic continuously variable transmission is disposed in a horizontal state in which the input shaft and the output shaft are positioned back and forth, the amount by which the hydrostatic continuously variable transmission projects upward from the transmission case. Can be reduced or set to zero. Moreover, by utilizing the fact that the hydrostatic continuously variable transmission is installed in the horizontal state, the vertical rotation shaft is arranged in a state between the input shaft and the output shaft in a side view. The input shaft is located forward of the front of the transmission case, so if the input shaft is extended and a hydraulic pump mounted on the other side of the transmission case is driven at the extended end, Of course, the input shaft can be extended without interference from the rotating shaft,
The extended portion of the input shaft does not need to be provided in the transmission case, and can be externally provided.

[Effect] Therefore, the operation steps arranged at the upper part of the transmission case can be set low, and the input shaft for driving the hydraulic pump or the like mounted on the other side of the transmission case by the input shaft can be easily extended. Now you can do it.

The features, functions and effects of the present invention according to claim 4 are as follows.

[Features] In the present invention according to the first, second and third aspects, the deceleration transmission mechanism from the vertical rotation shaft to the pitman arm shaft is configured so that the shafts are arranged in a horizontal direction. is there.

[Operation] Since the speed reduction transmission mechanism is configured so that the shafts are arranged in the horizontal direction and the length of the space for installing the speed reduction transmission mechanism is shortened, for example, when the shafts are arranged in the front and rear direction. The front surface of the transmission case in which the speed reduction transmission mechanism is mounted can be positioned rearward as compared with the case of FIG.

[Effect] Accordingly, the transmission case can be made compact in the front-rear direction, despite the provision of the speed reduction transmission mechanism.

The features, functions and effects of the present invention according to claim 5 are as follows.

[Features] In the present invention according to the first, second, third, and fourth aspects, the vertical rotation axis and the pitman arm axis are arranged concentrically, and the vertical rotation axis and the pitman arm axis are aligned. One of the shaft ends is supported by a transmission case via a bearing, and the other is fitted and supported by one of the shaft ends so as to be relatively rotatable.

[Operation] One end of a vertically-rotating shaft and a pitman arm shaft arranged concentrically is supported by a transmission case via a bearing, and the other end is fitted to one end of the shaft. Since the shaft end is supported, the shaft end supporting portion by the bearing and the other shaft end supporting portion by one shaft end can be provided at the same position in the axial direction.

[Effect] Accordingly, the bearing structure of the vertical rotation shaft and the pitman arm shaft can be compactly formed in the axial direction.

The features, functions and effects of the present invention according to claim 6 are as follows.

[Features] In the present invention according to the fourth and fifth aspects, the reduction transmission mechanism is a gear reduction mechanism, and a helical gear is incorporated.

[Operation] Since the reduction transmission mechanism is a gear reduction mechanism incorporating a helical gear, the steering operation can be transmitted from the vertical rotation shaft to the pitman arm shaft with little backlash.

[Effect] Accordingly, steering can be performed with little play.

[0029]

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 includes a transmission case 9 for supporting the driving front wheel 1 via a front axle case 8, and the driving rear wheel 2 The engine 11 is located near the front of the transmission case 9 in the body frame supported via the rear axle case 10.
Is mounted so that its output shaft 11a is positioned laterally via a vibration-proof rubber 12 (an example of a vibration-proof material), and the boarding operation unit 13 is mounted in a state where it is located behind the engine 11. ing.

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 at a level higher than the transmission case 9.

The seedling planting apparatus 4 is provided with a seedling stand 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 stand 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, the engine 1
A continuously variable hydrostatic continuously variable transmission 41 having a lateral input shaft 41a interlocked with the first output shaft 11a via a transmission 40, the output of which is output to the transmission case 9 by a lateral shaft. The input shaft 41a and the lateral output shaft 41b are connected to each other so as to be transmitted and transmitted.

The above-mentioned wrapping transmission device 40 includes an output shaft 11
The transmission belt 40c is wound around an output pulley 40a mounted on the input shaft 41a and an input pulley 40b mounted on the input shaft 41a, 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
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 the extending end of the input shaft 41a of the hydrostatic continuously variable transmission 41 is provided on the other side of the transmission case 9 on the left, right, side and other sides. 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. Hydraulic control valve 4 for lifting / lowering operation of working equipment
4 are attached.

The hydraulic system will be described in detail. The transmission case 9 is used as a hydraulic oil tank.
5, the hydraulic oil in the transmission case 9 is supplied to the hydrostatic stepless transmission 41 and the hydraulic pump 42, and the hydraulic oil from the hydraulic pump 42 is supplied to the torque generator 43, and then through the hydraulic control valve 44. It is supplied to the lifting cylinder 6. 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 drain of the hydraulic control valve 44 when the operation of the elevating cylinder 6 is stopped is returned to the transmission case 9. It is supposed to be.

Then, in the transmission case 9,
The main clutch for interrupting the power from the output shaft 41b of the hydrostatic continuously variable transmission 41, the gear shift type sub-transmission mechanism for high-low two-stage transmission, and the differential mechanism for the left and right driving front wheels 1 are transmitted by a traveling transmission system. A one-way clutch that transmits only forward power among the power from the main clutch, a speed change mechanism for changing the power between these strains, and a planting clutch that intermittently powers these powers. Is installed as a transmission element of the planting transmission system branched from the traveling transmission system. In addition, the front axle case 8 includes:
A transmission mechanism from the differential mechanism to the drive front wheel 1 is provided,
The rear axle case 10 includes a transmission mechanism for transmitting the rotation of the differential case transmitted from the differential mechanism via the transmission shaft to the driving rear wheel 2. L1 is a shift lever for operating the hydrostatic continuously variable transmission 41.

The steering device is shown in FIGS.
As shown in FIG.
A torque generator 43 for hydraulic power steering is connected so that its input shaft 43a is substantially perpendicular to the upper surface of the transmission case 9, and is integrated with the input shaft 43a of the torque generator 43 and the steering handle 14. Handle shaft 90 that rotates backward and tilts
And a pitman arm 92 which is interlocked with the torque generator 43 and swings around the longitudinal axis P, is attached to the transmission case 9 in a state located below the pitman arm. Arm 92
And a knuckle arm 93 of each drive front wheel 1.

The means for interlockingly connecting the torque generator 43 and the pitman arm 92 includes a vertically rotating shaft 95 which is interlockedly connected to the torque generator 43, provided concentrically with the pitman arm shaft 92a.
And a deceleration transmission mechanism 96 for transmitting the operation force to the pitman arm shaft 92a.

The deceleration transmission mechanism 96 is a gear reduction mechanism, and the intermediate transmission shaft 97 is rotatably mounted on the transmission case 9 at both upper and lower ends via bearings 98 in a state of being arranged beside the pitman arm shaft 92a. Vertical rotation axis 9
5, a small-diameter first transmission gear G1 is formed, and a large-diameter first driven gear g1 that meshes with and interlocks with the first transmission gear G1 is mounted on the intermediate transmission shaft 97 so as to rotate integrally therewith. A second transmission gear G2 is formed, and a large-diameter second driven gear g2 meshing with and interlocking with the second transmission gear G2 is mounted on the pitman arm shaft 92a so as to rotate integrally therewith. The first transmission gear G1, the first driven gear g1, the second transmission gear G2, and the second driven gear g2 are bevel gears with little backlash.

Means for interlockingly connecting the vertical rotation shaft 95 to the torque generator 43 is as follows.
Interlocking portion 99a having an internal spline structure that is fitted and connected to the swing output shaft 43b so as to be relatively swingable and in a torque transmitting state.
And an intermediate joint member 99 having an output portion 99b having an internal spline structure fitted and connected to the upper end of the vertical rotation shaft 95 in a torque transmitting state. This is a means for supporting a boss 9a formed on the transmission case 9 via a bush 100 while penetrating the top plate of the case 9 vertically. Means for fitting and connecting the interlocking portion 99a to the swing output shaft 43b so as to be relatively swingable and in a torque transmitting state is such that the outer surface of the tooth of the external spline of the swing output shaft 43b is formed into an arc surface around the center of swing. Means to form.

The pitman arm shaft 92a
Are rotatably supported by the transmission case 9 via bearings 101 at the upper end and upper and lower intermediate portions. The vertical rotation shaft 95 is provided at the upper end with the intermediate joint member 9.
9 and is supported at the lower end by a pitman arm shaft 92a.

The vertical rotation shaft 95 is provided on the input shaft 41a of the hydrostatic continuously variable transmission 41 in a side view.
And the output shaft 41b.

[Alternative Embodiment] In the above embodiment, the pitman arm shaft 92a is supported by the transmission case 9 via the bearing 101, but the end of the vertical rotation shaft 95 is supported by the transmission case 9 via the bearing 101. Support
A pitman arm shaft 92 is attached to the end of the vertical rotation shaft 95.
It may be carried out by fitting and supporting the end of “a”.

[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 a front view of a main part.

FIG. 6 is a cutaway side view of a main part of the steering device.

FIG. 7 is a cutaway front view of a main part of the steering device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front wheel 9 Transmission case 41 Hydrostatic continuously variable transmission 41a Input shaft 41b Output shaft 43 Torque generator 43a Input shaft 43b Swing output shaft 90 Handle shaft 91 Universal joint 92a Pitman arm shaft 95 Vertical rotation shaft 96 Reduction transmission mechanism 99 Intermediate joint member 99a Interlocking part 99b Output part 101 Bearing

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Shinsuke Kotani 64 Ishizu-Kitacho, Sakai City, Osaka Prefecture Inside Kubota Sakai Factory (72) Inventor Naoki 64, Ishizu-Kitacho Sakai City, Osaka Prefecture Kubota Sakai Manufacturing Co., Ltd In-house (72) Inventor Takashi Shimizu 64 Ishizu-Kitacho, Sakai-shi, Osaka F-term in Kubota Sakai Works (reference) 2B062 AB01 BA41 3D033 DC01 HA00

Claims (6)

[Claims] 1. A torque generator for hydraulic power steering is connected to an upper surface of a transmission case disposed above a steering front wheel, and a vertically rotating shaft interlocked with the torque generator and a pitman arm supported by the transmission case. A steering device for a paddy working machine having a shaft and an interlocking connection, wherein the vertical rotation shaft is interlockingly connected to the torque generator so that the rotation output shaft of the torque generator is relatively swingable and in a torque transmitting state. A steering device for a paddy working machine, wherein an intermediate joint member having an interlocking portion that is fitted and interlocked and an output portion to a vertical rotation shaft is rotatably supported on a transmission case around a vertical axis. 2. A torque generator is arranged such that an input shaft thereof is substantially perpendicular to an upper surface of a transmission case, and the input shaft and a handle shaft installed in a rearward inclined posture are connected via a universal joint. The steering device for a paddy field working machine according to claim 1, wherein the steering device is interlocked. 3. A hydrostatic continuously variable transmission is disposed on one lateral side of a transmission case such that a lateral input shaft thereof and an output shaft into the transmission case are positioned forward and backward, and the input is viewed in a side view. The steering device for a paddy working machine according to claim 1 or 2, wherein the vertical rotation shaft is disposed between the shaft and the output shaft. 4. The paddy field working machine according to claim 1, wherein the reduction gear transmission mechanism from the vertical rotation shaft to the pitman arm shaft is configured such that the shafts are arranged in a horizontal direction. Steering device. 5. A vertical rotation shaft and a pitman arm shaft are arranged concentrically, and one of the shaft ends of the vertical rotation shaft and the pitman arm shaft is supported by a transmission case via a bearing, and The steering device for a paddy field working machine according to any one of claims 1 to 4, wherein the other is fitted and supported on one of the other so as to be relatively rotatable. 6. The steering apparatus for a paddy working machine according to claim 4, wherein the reduction transmission mechanism is a gear reduction mechanism, and the helical gear is incorporated.