JPH0551244B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention uses a planting claw to take out a single seedling from a seedling stand that slides back and forth from side to side, and at the same time drives the front and rear wheels to travel. This invention relates to a traveling device for a riding rice transplanter that moves at a constant speed and performs rice transplanting work continuously.

"Prior Art" Conventionally, as shown in Japanese Patent Application Laid-Open No. 54-120138, there has been a technology in which a power cylinder is provided to drive the front and rear wheels and also to steer the front wheels in conjunction with the operation of the steering wheel.

"Problems to be Solved by the Invention" The prior art described above was equipped with a speed change cylinder that changes the rotational speed of the front wheels and a speed change valve that controls the operation of the cylinder. Because the valve was connected to the steering wheel, it was not easy to set the switching stroke of the steering control valve and transmission valve, or adjust the oil pressure switching timing. When the front wheels rotate at high speeds, the slips of the front wheels apply shock to the planting area, causing the seedlings on the seedling stand to become uneven and disturbing the planted seedlings or the field surface. If the rotation of the front wheels increased to high speed after a delay after the steering operation, there were problems in handling such as the front wheels slipping at the beginning of a turn.

"Means for Solving the Problem" However, the present invention not only drives the front and rear wheels, but also
In a traveling device for a riding rice transplanter that includes a power cylinder that steers the front wheels in conjunction with steering handle operation, a speed change cylinder that changes the rotational speed of the front wheels;
The present invention is characterized in that it is provided with a speed change valve for controlling the operation of the cylinder, the speed change valve is connected to a piston rod of the power cylinder, and the speed change valve is switched by the forward and backward movement of the piston rod of the power cylinder.

``Function'' Therefore, since the speed change valve is connected to the piston rod and the front wheel steering operation and the speed change valve switching operation are linked, it is possible to set the oil pressure switching timing of the speed change valve more easily than before, and the front wheel steering operation is made easier. It is possible to change the rotation of the front wheels without slowing down the operation, and since the speed change valve is installed regardless of the steering control valve that controls the operation of the power cylinder, the structure of the speed change valve body and the mounting structure are simplified. This makes it possible to easily improve handling and operability and reduce manufacturing costs compared to conventional methods.

"Embodiments" Examples of the present invention will be described in detail below based on the drawings. Fig. 1 is a hydraulic circuit diagram, Fig. 2 is a side view of the riding rice transplanter, and Fig. 3 is a plan view of the same. 3, the rear end of the transmission case 4 is connected to the transmission case 4, and front wheels 6 for running in paddy fields are supported on both sides of the front part of the transmission case 4 via a front axle case 5.
A transmission case 7, which is an axle case, is connected to both rear sides of the vehicle, and a rear wheel 8 for running in paddy fields is supported at the rear end of the transmission case 7. Spare seedling stands 10 are attached to the outside of both sides of the bonnet 9 that covers the engine 2, etc., and a vehicle body cover 1 forming a step 11 is attached.
2 covers the transmission case 7, etc., a driver's seat 13 is attached to the upper part of the vehicle body cover 12, and a steering handle 14 is provided at the rear of the bonnet 9 in front of the driver's seat 13.

Further, numeral 15 in the figure is a planting section that includes a seedling stand 16 for multi-row planting, a plurality of planting claws 17, etc., and a rear-tilting seedling stand 16 with a high front and a low rear is connected to a guide rail 18. and the planting case 2 via the guide rail 19.
The planting claws 17 are attached to the planting case 20 via a planting arm 22 that is supported by the 0 in a reciprocating manner and is moved by a crank, and a planting claw drive shaft 21.
Install. Further, a support frame 24 is provided on the front side of the planting case 20 via a center pin 23, and the support frame 24 is connected to the rear side of the traveling vehicle 1 via a three-point link mechanism 27 including a top link 25 and a lower link 26. , a lifting cylinder 28 that lifts and lowers the planting section 15 via the link mechanism 27;
The front and rear wheels 6 and 8 are driven to move at a substantially constant speed, and at the same time, one seedling is taken out by a planting claw 17 from a seedling platform 16 that slides back and forth from side to side. The system is configured to carry out rice planting work.

In addition, in the figure, 29 is a traveling speed change lever, 30 is a planting lift lever, 31 is a planting sensitivity adjustment lever, 32
is a traveling clutch pedal, 33, 33 are left and right brake pedals, 34... is a float for field leveling, and the float 34... is supported on the lower side of the planting case 20 via a planting depth adjustment link 35, etc. are doing.

As shown in FIGS. 4 and 5, the steering wheel 14 is rotated left and right to control the steering of the front wheels 6, and the steering box 3 transmits the rotational displacement of the steering wheel 14 to the pitman arm 36.
7, and a rotation fulcrum shaft 39 on the axle transmission case 38.
a swing plate 40 which is a steering arm supported swingably through the swing plate 40, a steering control valve 42 which is a drag rod interposed between one end of the arm 41 fixed to the swing plate 40 and the pitman arm 36, and the arm 41. A steering power cylinder 43 which is a power steering actuator part that is interposed between the other end and the vehicle body frame 3 and connects the piston rod 44 to the arm 41, and left and right knuckle arms 45, 45 which are integrally connected to the front axle case 5. It is provided with connection rods 46 and 47 that are tie rods that connect the swing plate 40, respectively, and a damper 48 for preventing swing hunting interposed between the swing plate 40 and the transmission case 38. When the rotational displacement occurs, the spool 42a of the control valve 42 moves forward and backward, and the power cylinder 43 is expanded and contracted appropriately to change the direction of the front wheel 6, and at the time of the conversion, the displacement of the cylinder 43 is fed back to the control valve 42 via the arm 41, The control valve 42
It is configured to return to neutrality. Further, the control valve 42 is connected to a hydraulic pump 49 fixed to the vehicle body frame 3 via a hose 50, and is connected to the control valve 42 via two oil supply and oil return hoses 51 and 52 parallel to the cylinder 43. are connected.

As shown in FIG. 1, a hydraulic pump 49 is connected to the hydraulic cylinder 28 for raising and lowering the planting section 15 via the lifting valve 53 and the control valve 42, and the restricting valve 55 of the diverting valve 54 is connected to the hydraulic pump 49 via the lifting valve 53 and the control valve 42. The control valve 42 and the valve 53 are provided in series through the control valve 42, and the valve 53 is switched by operating the planting lift lever 30 to control the operation of the hydraulic cylinder 28, raising and lowering the planting section 15, and operating the steering handle 14. The transmission cylinder 56 is a transmission member that changes the rotational speed of the front wheel 6 in conjunction with the transmission cylinder 56, and the transmission valve 57 that controls the operation of the cylinder 56.The transmission valve 57 is attached to the power cylinder 43, and the transmission valve 57 has a spool. 57a is connected and fixed to the piston rod 44 of the power cylinder 43, and the speed change valve 57 is connected to the hydraulic pump 49 via the throttle valve 58 of the diverter valve 54. When the steering handle 14 is rotated left and right by more than a set angle, the power cylinder 43 operation, the speed change valve 57 is switched at a steering angle greater than or equal to the set steering angle, and the speed change cylinder 56 is moved forward, while the speed change cylinder 56 is moved backward by the return spring 59 when the speed change valve 57 is in the neutral position. . As is clear from the above, the rotational speed of the front wheel 6 is changed in the traveling device of the riding rice transplanter, which is provided with a power cylinder 43 that drives the front and rear wheels 6 and 8 and steers the front wheel 6 in conjunction with the operation of the steering handle 14. Shift cylinder 5
6 and a speed change valve 57 for controlling the operation of the cylinder 56, the speed change valve 57 is connected to the piston rod 44 of the power cylinder 43, and the speed change valve 57 is switched by the forward and backward movement of the piston rod 44 of the power cylinder 43. ing.

Further, as shown in FIG. 6, the input shaft 60 of the transmission case 4 is connected to the engine 2, and the front and rear output shafts 61, 62 of the transmission case 4 are
The front and rear wheels 6, 8 are connected to each other via a differential mechanism 63 and a side clutch mechanism 64, and the front and rear wheels 6, 8 are driven.

The input shaft 60 is interlocked with the output shafts 61 and 62 via a counter shaft 65, and between the input shaft 60 and the counter shaft 65 is a constant bite reduction gear 66 for auxiliary transmission that performs two high and low speed changes. , 67 and 68, 6
9 is interposed, and the gear 6 of the counter shaft 65
The intermediate transmission body 70, which is a coupling sleeve interposed between 7 and 69, is connected to the gear 6 through each clutch 71 and 72.
7 and 69, the counter shaft 65 is provided to rotate at high or low speed. A pair of reduction gears 73 and 74 are interposed between the counter shaft 65 and the output shaft 62, and by meshing and operating the gears 73 and 74, the output shaft 62 is moved to the first forward speed. It is configured to rotate depending on the state.

On the other hand, the counter shaft 65 is provided with constant mesh gears 69, 7.
The transmission case 4 is equipped with a back gear shaft 76 which is interlocked and connected through the gear shaft 76, and the output shaft 62 is rotated in a backward state by engaging and operating the gear 74 with a back gear 77 which is integrally supported on the gear shaft 76. It consists of

Further, a large diameter gear 78 is integrally supported on the input shaft 60, and the gear 78 is always engaged with a small diameter gear 79 freely rotatably supported on the gear shaft 76. The meshing operation causes the output shaft 62 to rotate in the second forward speed state.

Further, the counter shaft 65 integrally supports transmission gears 80, 81, 82 for adjusting the distance between plants, and the gears 84, 85 for adjusting the distance between plants, which are slidably connected to the planting drive transmission shaft 83, are connected to the respective gears 80, 81. , 82 to adjust the spacing between plants (adjust the planting speed) in the planting section 15.

Further, each of the output shafts 61 and 62 is freely connected,
The front wheel counter shaft 88 is always interlocked and connected to the front output shaft 61 via transmission gears 86 and 87 with the same number of teeth that are always engaged, and the constant velocity transmission gear 89 and the high speed transmission gear 90 are connected to the rear output shaft 62. Support me,
A constant velocity gear 91 and a high speed gear 92 are freely rotatably supported on a front wheel counter shaft 88, and each gear 89, 9 has the same number of teeth.
1 and gears 90 and 92 for speed-up output, and a wet multi-disc type constant-velocity and high-speed side clutch 93 that engages and connects the constant-velocity and high-speed gears 91 and 92 to the front wheel counter shaft 88. , 94,
A clutch arm 96 is integrally connected to a clutch fork 95 that engages and operates each clutch 93, 94, and a bracket 97 is attached to the transmission case 4.
When the speed change cylinder 56 is attached through the cylinder 56, the piston rod 98 of the cylinder 56 is connected to the clutch arm 96, and the piston rod 98 is projected by the return spring 59, the constant speed side clutch 93 is engaged and held, and the constant speed is maintained. The front and rear output shafts 61 and 62 are driven at the same rotation speed through the gear 91, and when the steering angle of the steering handle 14 exceeds a set value, the speed change cylinder 56 is actuated through the speed change valve 57, and the piston rod 98 is retracted. The high-speed side clutch 94 is engaged and the front output shaft 61 is rotated at a higher speed than the rear output shaft 62 via the high-speed gear 92, so that the rotational speed of the front wheels 6 during turning is higher than that of the rear wheels 8. The speed change cylinder 56 is automatically controlled in conjunction with the operation of the power cylinder 43 to achieve high speed.

The present embodiment is configured as described above, and when the handle 14 is rotated left and right, the spool 42a of the control valve 42 advances or retreats by a certain amount accordingly, switching the control valve 42 from the neutral position to the power cylinder 43. High pressure hydraulic oil is supplied from the pump 49. As the piston rod 44 of the cylinder 43 expands and contracts, the rocking plate 4 is moved through the arm 41.
0 swings to the left or right about the fulcrum shaft 39 to change the direction of the front wheels 6 and return the control valve 42 to neutral, causing the piston rod 44 to advance in proportion to the steering angle of the steering handle 14. The amount changes, and in conjunction with the piston rod 44, the speed change valve 5
Since the spool 57a of No. 7 is activated, when the steering angle of the handle 14 exceeds the set value when changing direction at a headland, etc., the speed change valve 57 is switched in conjunction with the power cylinder 43, and the speed change cylinder 5
6's piston rod 98 is retracted, the constant speed side clutch 93 is disengaged, and the high speed side clutch 94 is switched on, respectively, to rotate the outer front wheel 6, which has the largest turning radius, at high speed, and move the inner rear wheel on the rear side of the traveling vehicle 1. This system causes the traveling vehicle 1 to turn around the wheels 8 to change direction, and prevents skidding force from acting on the front wheels 6 due to the propulsive force of the outer rear wheels 8.
Since the gear shift valve 57 is operated in conjunction with 3,
Without increasing the steering force of the steering handle 14 and without the need to provide a special mechanism for detecting the steering angle of the front wheels 6, the operation of the speed change cylinder 56 can be appropriately controlled in conjunction with left and right turning operations of the handle 14. It is possible.

"Effects of the Invention" As is clear from the above embodiments, the present invention provides a power cylinder 43 that drives the front and rear wheels 6 and 8 and steers the front wheels 6 in conjunction with the operation of the steering handle 14.
In the traveling device of a riding rice transplanter equipped with
The piston rod 44 of the power cylinder 43 is equipped with a speed change cylinder 56 for changing the rotation speed of the piston rod 44 of the power cylinder 43, and a speed change valve 57 for controlling the operation of the cylinder 56.
The speed change valve 57 is connected to the front wheel 6, and the speed change valve 57 is switched by the forward and backward movement of the piston rod 44 of the power cylinder 43.The speed change valve 57 is connected to the piston rod 44 to control the steering operation of the front wheels 6 and the speed change valve. Since the switching operations of the transmission valves 57 and 57 are linked, it is possible to set the oil pressure switching timing of the transmission valve 57 more easily than before.
The rotation of the front wheels 6 can be changed without slowing down the steering operation of the front wheels 6, and since the speed change valve 57 is installed regardless of the steering control valve 42 that controls the operation of the power cylinder 43, the speed change valve 57 body It is possible to easily simplify the structure and the mounting structure, and it is possible to easily improve handling operability and reduce manufacturing costs compared to the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a hydraulic circuit diagram showing an embodiment of the present invention;
Figure 2 is a side view of the whole, Figure 3 is a plan view of the same, Figure 4
The figure is a side view of the main part, FIG. 5 is a plan view of the same, and FIG. 6 is a sectional view of the mission case. 6... Front wheel, 8... Rear wheel, 14... Steering handle, 43... Power cylinder (power steering actuator part), 56... Speed change cylinder (speed change member).

Claims (1)

[Claims] 1. In a traveling device for a riding rice transplanter that is provided with a power cylinder 43 that drives the front and rear wheels 6, 8 and also steers the front wheel 6 in conjunction with the operation of the steering handle 14, a speed change cylinder 5 that changes the rotational speed of the front wheel 6.
6, and a speed change valve 57 for controlling the operation of the cylinder 56, the speed change valve 57 is connected to the piston rod 44 of the power cylinder 43, and the speed change valve 57 is configured to be switched by the forward and backward movement of the piston rod 44 of the power cylinder 43. A traveling device for a riding rice transplanter characterized by the following.