JP2002307961A - Work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a machine body and reduce its weight by easily simplifying the drive configuration of a running member such as a running crawler. SOLUTION: In this work vehicle transmitting driving forces for straight advance and turn of a hydraulic continuously variable transmission member 25 and a steering member 28 to right and left running member 2 through right and left planetary gear mechanisms 35 to advance straight, turn, and run the machine body, the hydraulic continuously variable transmission member 25 and the hydraulic continuously variable steering member 28 are arranged on opposing side faces of a transmission case 22, and the right and left running members 2 are arranged on lower sides of the continuously variable transmission member 25 and the steering member 28 so as to lap them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working vehicle such as a combine or cultivating tractor or a field management vehicle for continuously cutting and threshing grain culms in a field.

[0002]

Conventionally, a hydraulic stepless transmission member for changing a vehicle speed formed by a transmission pump and a motor,
The driving force of the hydraulic stepless steering member for changing the traveling course formed by the steering pump and the motor is transmitted to the traveling crawler via the planetary gear mechanism, and the transmission member and the steering are operated by operating the main transmission lever and the steering handle. In the case of a work vehicle having a shift means and a steering mechanism for controlling the output of the steering member, the shift member and the steering member, and other operation lever systems and accessory parts when the shift and steering mechanism is incorporated into the body of the vehicle. There was a problem that a compact body could not be easily assembled due to interference with the robot.

[0003]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a straight traveling and turning traveling of an airframe by transmitting a straight traveling and turning driving force of a hydraulic continuously variable transmission member and a steering member to a left and right traveling member via a left and right planetary gear mechanism. In the working vehicle, the hydraulic continuously variable transmission member and the hydraulic continuously variable steering member are arranged on the opposite side surface of the transmission case, and the left and right traveling members are arranged below the continuously variable transmission member and the steering member. It is arranged so that it wraps, making effective use of the empty space above the traveling members such as the left and right traveling crawlers, and the hydraulic continuously variable transmission member and steering member are integrated and compactly installed in the transmission case to reduce the size and weight of the aircraft and the left and right This makes it possible to easily improve the balance.

Further, a transmission and steering mechanism for controlling the output of the transmission member and the steering member is provided between the main transmission lever and the steering handle and the hydraulic stepless transmission member and the steering member. The gearbox and steering mechanism are effectively arranged in the extra space formed under the driver's seat below the step on the front side, and the steering column etc. required for installing these gearshifting and steering mechanisms Space is effectively reduced, and the body can be easily reduced in size and weight.

Further, there is provided a shift and steering mechanism interposed between the main shift lever and the steering handle and the hydraulic stepless shift member and the steering member to control the output of the shift member and the steering member. The transmission and steering mechanism and the transmission mechanism are arranged in a single transmission case, and the transmission and steering mechanism and the transmission mechanism are connected in the transmission case to form the transmission case and the steering column separately. To reduce the complexity of the structure and increase the weight of the vehicle, and to easily incorporate the shifting and steering mechanism, the transmission mechanism, and their coupling mechanism into a single transmission case, making it easier to reduce the size and weight of the aircraft. In addition, the cost can be reduced.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. Fig. 1 is an overall side view of the combine, Fig. 2
1 is a plan view of the same. In the figure, 1 is a track frame on which a traveling crawler 2 as a pair of right and left traveling members is mounted, 3 is a machine frame installed on the track frame 1, 4 is a feed chain 5 stretched to the left side. A threshing unit having a built-in handling cylinder 6 and a processing cylinder 7; a cutting unit 8 including a cutting blade 9 and a grain culm transport mechanism 10; a hydraulic cylinder 11 for raising and lowering the cutting unit 8 via a cutting frame 12; 13 is a straw processing unit that faces the end of the straw chain 14, 15 is a grain tank that carries in the grains from the threshing unit 4 through a fryer 16, and 17 is the tank 1.
5, a discharge auger for carrying out the grains 5 out of the machine; 18 a cab provided with a round steering handle 19 and a driver's seat 20;
Reference numeral denotes an engine provided below the driver's seat 20 and is configured to continuously cut and threat grain culms.

Further, as shown in FIG. 3, a transmission case 22 for driving the traveling crawler 2 includes a pair of first hydraulic pumps 23 and a first hydraulic motor 24, and is a hydraulic stepless transmission for traveling main transmission. A transmission member 25 forming a mechanism;
A steering member 2 including a pair of second hydraulic pumps 26 and a second hydraulic motor 27 to form a hydraulic hydraulic continuously variable transmission mechanism for turning.
8, the input shafts 29 of the first and second hydraulic pumps 23 and 26 are connected to the output shaft 21a of the engine 21 by a transmission belt 30 to drive the pumps 23 and 26.

The output shaft 3 of the first hydraulic motor 24
1, the driving wheels 34 of the left and right traveling crawlers 2 are interlockingly connected via a subtransmission mechanism 32 and a differential mechanism 33.
The differential mechanism 33 includes a pair of symmetric planetary gear mechanisms 35.
35, and each planetary gear mechanism 35 has one sun gear 3
6, three planetary gears 37 meshing on the outer periphery of the sun gear 36, and a ring gear 38 meshing with the planetary gears 37.

The planetary gear 37 has a sun gear shaft 39.
The carrier 41 of the carrier shaft 40 is rotatably supported on the coaxial line, and the left and right carriers 41 are arranged to face each other across the left and right sun gears 36. The ring gear 38 meshes with each planetary gear 37. 38a, which is disposed on the same axis as the sun gear shaft 39, is rotatably supported by the carrier shaft 40, extends the carrier shaft 40 to form an axle, and supports the drive wheel 34. I have.

A traveling hydraulic continuously variable transmission member 25 is also provided.
Performs forward / reverse rotation and rotation speed control of the first hydraulic motor 24 by adjusting the angle of the rotary swash plate of the first hydraulic pump 23. The rotation output of the first hydraulic motor 24 is transmitted to the transmission gear of the output shaft 31. The transmission is transmitted from a gear 42 to a center gear 46 fixed to a sun gear shaft 39 via the respective gears 43, 44, 45 and the auxiliary transmission mechanism 32 to rotate the sun gear 36. The auxiliary transmission mechanism 32 includes an auxiliary transmission shaft 47 having the gear 44, and a parking brake shaft 49 having a gear 48 that meshes with a center gear 46 via the gear 45.
A pair of low-speed gears 50 and 51, medium-speed gears 52 and 53, and high-speed gears 54 and 51 are provided between the auxiliary transmission shaft 47 and the brake shaft 49.
48, a low-medium speed slider 55 and a high speed slider 5
The sub-shift is switched between low speed, medium speed, and high speed by the slide operation of No. 6. Note that there is neutrality between low and medium speeds and between medium and high speeds. The brake shaft 4
9, a parking brake 57 is provided, and a cutting PTO gear for transmitting a rotational force to the cutting unit 8 is provided on the auxiliary transmission shaft 47.
The reaping unit 8 is driven at the vehicle speed synchronization speed.

As described above, the driving force from the first hydraulic motor 24 transmitted to the sun gear shaft 39 via the center gear 46 is transmitted to the left and right carrier shafts 40 via the left and right planetary gear mechanisms 35 and The rotation transmitted to the carrier shaft 40 is transmitted to the left and right drive wheels 34, respectively, and the left and right traveling crawlers 2 are driven.

Further, a steering member 28 formed by a turning hydraulic continuously variable transmission mechanism is provided with a forward / reverse rotation and a rotation speed of the second hydraulic motor 27 by adjusting the angle of the rotary swash plate of the second hydraulic pump 26. The control includes a brake shaft 60 having a steering output brake 59, a clutch shaft 62 having a steering output clutch 61, and external teeth 3 of the left and right ring gears 38.
8b are provided with left and right input gears 63 and 64 which are always engaged with each other.
The output shaft 27 a of the second hydraulic motor 27 is connected to the brake shaft 6.
0, a clutch shaft 62 is connected via a steering output clutch 61, a right input gear 64 is connected to the clutch shaft 62 via a forward rotation gear 65, and a forward rotation gear 65 and a reverse rotation gear 66 are connected to the clutch shaft 62. The left input gear 63 is connected via the input gear 63. Then, while the brake 59 is engaged and the clutch 61 is disengaged by the neutral position of the sub-transmission sliders 55 and 56, the brake 5
9 is turned off and the clutch 61 is turned on, and the motor 27 is connected to the external teeth 38b of the right ring gear 38 via the forward rotation gear 65.
It transmits the torque and the external teeth 38b of the left ring gear 38.
The rotation of the motor 27 is transmitted to the second hydraulic motor 27 via the forward rotation gear 65 and the reverse rotation gear 66, and when the second hydraulic motor 27 rotates forward (reverse rotation), the left ring gear 38 rotates reversely (forward rotation) at the same left and right rotation speeds.
The right ring gear 38 is configured to rotate forward (reverse).

With the second hydraulic motor 27 for turning stopped and the left and right ring gears 38 stationary and fixed,
When the first hydraulic motor 24 for traveling is driven, the rotational output from the first hydraulic motor 24 is transmitted from the center gear 46 to the left and right sun gears 36 at the same rotational speed, and is transmitted via the planetary gear 37 of the left and right planetary gear mechanism 35 and the carrier 41. The left and right traveling crawlers 2 are driven at the same rotational speed in the same rotational direction in the left and right directions, so that the body travels straight in the front-rear direction. On the other hand, when the first hydraulic motor 24 for traveling is stopped and the left and right sun gears 36 are stationary and the second hydraulic motor 27 for rotation is driven forward and reverse, the left planetary gear mechanism 35 is driven forward or backward. The reverse rotation and the right planetary gear mechanism 35 rotate in the reverse or forward direction, drive the left and right traveling crawlers 2 in the reverse direction, and turn the body to the left or right. Also, by driving the second hydraulic motor 27 for turning while driving the first hydraulic motor 24 for traveling, the aircraft turns left and right to correct the course, and the turning radius of the aircraft is It is determined by the output rotation speed of the two hydraulic motors 27.

As shown in FIGS. 2, 4 to 7, a steering column 67 is erected on the front upper surface of the driver's cab 18 and the steering handle 19 is rotated about the vertical axis above the steering column 67 upper surface. At the same time, a side column 68 is provided on the left side of the driver's cab 18.
The transmission 22 is disposed below the main transmission lever 69,
The sub transmission lever 70, the reaping clutch lever 71, and the threshing clutch lever 72 are attached to the side column 68. Further, the steering column 67 is formed by molding an aluminum alloy casting, and is formed into a box shape which is divided into right and left parts and is fastened with a plurality of bolts.

An upper end of the handle shaft 73 is connected to the steering handle 19, and the handle shaft 73 is rotatably supported on the upper part of the steering column 67. An upper end of the steering input shaft 74 is mounted on the upper part of the steering column 67. The shaft 75 is rotatably supported, and the gear 75 of the handle shaft 73 and the sector gear 76 of the steering input shaft 74 are engaged with each other to connect the shafts 73 and 74. 74 is extended.

Further, a bearing member 77 is removably fixed to the left side surface of the steering column 67 at substantially the center in the vertical direction, and one end of the transmission input shaft 78 is rotatably supported by the bearing member 77 via a bearing. And the speed change input shaft 78
And the steering input shaft 7
4, the upper end side of the input fulcrum shaft 80 is connected to the lower end via a universal joint 79, and the input member 81 is fixed to the input fulcrum shaft 80;
The input member 81 is rotatably attached to the speed change input shaft 78 via a bearing, and the input member 81 is
2 is detachably fixed, and the input member 81 is connected to the steering input shaft 7.
The input member 81 is rotatably supported on the center of the input shaft 81 by rotating the steering input shaft 74 forward or backward.
The transmission input shaft 78 is rotated forward and reverse around the four core wires.
The input fulcrum shaft 80 and the input member 81 are rotated about the substantially horizontal input shaft 78 core line in the horizontal direction by the forward / reverse rotation of. Further, a universal joint 79 is mounted at an intersection where the vertical steering input shaft 74 core line and the left and right horizontal transmission input shaft 78 core line intersect at right angle, and the steering is performed by the steering input shaft 74 forward / reverse operation of the steering handle 19. The input member 81 and the input connector 82 are rotated forward and reverse around the input shaft 74 core line.

A main transmission shaft 83 is rotatably supported at the lower front side of the steering column 67, and the left end of the main transmission shaft 83, which is laid substantially horizontally in the left-right direction, is located outside the left side of the steering column 67. The main transmission shaft 83 is connected via a rod 85 to an intermediate shaft 84 rotatably provided on the machine base 3 below the side column 68 and the main transmission lever 69 is swung in the front-rear direction around a lever fulcrum shaft 86. The main transmission shaft 83 is rotated forward and reverse by the moving speed change operation. Further, a main transmission shaft 83 is connected to a transmission input shaft 78 via a transmission arm 87 and a link 88, and the input member 81 is moved forward and backward around the center line of the transmission input shaft 78 by the forward / reverse operation of the main transmission lever 83 of the main transmission lever 69. To tilt.

Further, a steering output shaft 89 having a cylindrical shape is rotatably mounted on the main transmission shaft 83 so that the steering output link 90 is fixed to the steering output shaft 89 and the upper end of the steering rod 91 is fixed to the steering output shaft 89. A steering mechanism 93 is connected to the input connector 82 via a universal joint 92, and the lower end of the steering rod 91 is connected to a steering output link 90 via a ball joint to change the traveling course. ing.

Also, above the steering output shaft 89, the shaft 8
9, the transmission output shaft 94 is connected to the steering column 67.
The transmission output link 95 is fixed to the transmission output shaft 94 so as to be rotatable inside, and the upper end of the transmission rod 96 is connected to the input connector 82 via a universal joint 97, and is connected via a ball joint. The lower end of the speed change rod 96 is connected to a speed change output link 95 to constitute a speed change mechanism 98 for changing the traveling speed and switching between forward and backward.

Further, the inner steering operation shaft 99 and the outer speed change operation shaft 100 having a double shaft structure rotatable with each other are rotatably mounted at the lower rear side of the steering column 67 at the center in the left and right widths. The speed change output shaft 9 through a ball joint shaft 101 and a speed change link 102/103 that can be adjusted.
4 is connected to the upper end of the speed change operation shaft 100, and the ball-and-joint joint shaft 104 and the steering link 105.1 are adjustable in length.
06, the upper end of the steering operation shaft 99 is connected to the steering output shaft 89.

The operating shafts 99 and 100 are erected substantially vertically on the same axis at the bottom of the steering column 67, and the upper ends of the operating shafts 99 and 100 are extended inside the steering column 67 so that the respective output shafts The shafts 89 and 94 are connected to each other.
A lower end of each of the operation shafts 99 and 100 extends from the lower surface of the driver's cab 18 to the lower side of the operator's boarding step. And a turning rod 110 to the lower end of the steering shaft 99 via a turning link 109.

As shown in FIG. 8, the transmission case 2
2. The speed change and steering cases 111 and 112 having a hydraulic unit structure are detachably fixed to the left and right side surfaces of the upper part,
A hydraulic stepless transmission member 25 formed by the hydraulic pump 23 and the motor 24 and a hydraulic stepless steering member 28 formed by the second hydraulic pump 26 and the motor 27 are connected to each of the cases 111 and 11.
2 and the driving force of the engine 21 is
To drive the first and second hydraulic pumps 23 and 26 and to control the vehicle speed and steering control arm 1 of each output control shaft 113 and 114 provided on the transmission member 25 and the steering member 28.
The vehicle speed and the turning rods 108 and 110
And the first hydraulic pump 23 adjusts the swash plate angle by the forward / reverse operation of the output control shaft 113, and the first hydraulic motor 2
4 to perform stepless change of the traveling speed (vehicle speed) and forward / reverse switching, and to perform swash plate angle adjustment of the second hydraulic pump 26 by forward / reverse operation of the output control shaft 114. The rotation speed control and forward / reverse switching of the second hydraulic motor 27 are performed, so that the steering angle (turning radius) is steplessly changed and the left / right turning direction is switched.

The right and left traveling crawlers 2 and 2 are disposed under the shift and steering cases 111 and 112 so as to overlap with each other. The steering member 28 can be mounted compactly on the transmission case 22.

In FIG. 8, the transmission member 25, the first hydraulic pump 23 and the motor 24 of the steering member 28, and the second hydraulic pump 26 and the motor 27 are provided in a structure to be vertically overlapped in the cases 111 and 112. However, as shown in FIG. 9, a structure in which they are arranged side by side in the left-right direction may be used.
Minute case 111 for reducing vertical dimension of 11 ・ 112
The height above the space can be effectively utilized by reducing the installation height of the 112.

FIGS. 10 and 11 show a steering mechanism 93 and a speed change mechanism 98 formed by the link mechanism of the above embodiment.
Of the driver's cab 1 by tilting the steering input shaft 74 in the steering case 117 horizontally in the front-rear direction.
8 is provided below the step 118, and the steering case 11 is provided on the rear side of the step 118 in front of the driver's seat 20.
The steering input shaft 74 is connected to the handle shaft 73 via a bevel gear 119, and the speed change input shaft 7
The main transmission lever 69 is connected to the transmission output shaft 94 via the transmission rod 120, and the transmission member 25 fixed to the upper side of the transmission case 22 via the vehicle speed rod 108 and the turning rod 110 to the transmission output shaft 94 and the steering output shaft 89. The control arms 115 and 116 of the directional member 28 are connected to each other so as to perform stepless change of the traveling speed and stepless change of the steering angle as in the case described above. In this embodiment, the steering mechanism 93 and the speed change mechanism 98 are effectively arranged in an excess space formed below the step 118 in front of the driver's seat 20, and these mechanisms 93 and 98 are provided inside the steering column 67. As compared with the above, the driving operation space around the column 67 is enlarged by making the steering column 67 smaller or eliminated, and the driving operability is improved. For example, the handle shaft 73 is moved forward on the step 118 via the fulcrum shaft 121. It is also possible to operate the steering handle 19 from the field by being provided to be tiltable.

FIGS. 12 and 13 show a case in which the steering case 67 and the transmission case 22 in which the steering mechanism 93 and the speed change mechanism 98 of the above-described embodiment are provided are formed in an integrated speed change case 122. The upper side of the transmission case 122 is a steering column portion 122a in which the steering mechanism 93 and the transmission mechanism 98 are provided, and the lower side is a transmission mechanism such as the transmission member 25 and the steering member 28 and the auxiliary transmission and differential mechanisms 32 and 33. Is formed in a transmission case portion 122b in which the steering and transmission mechanisms 93 and 98 are connected to the transmission and steering members 25 and 28. Of the steering and transmission mechanisms 93 and 98 and the transmission and steering member 25.
28 and the like are simply incorporated so that the size and weight of the body can be reduced easily and at low cost.

As shown in FIG. 14, the steering handle 19
Also includes a lever-type handle 19a. The lever-type handle 19a is connected to the steering input shaft 74 via a pair of bevel gears 123 and 124, and when the handle 19a is tilted in the left-right direction, the steering input shaft 74 is By rotating the body forward and backward, the vehicle body is turned left and right during traveling, and the vehicle speed is reduced.

As shown in FIG. 15, the main transmission lever 69
Includes a speed-up switch 125 and a deceleration switch 126. For example, the grip portion 69a of the main shift lever 69
Are provided with speed increasing and decelerating switches 125 and 126,
When the switches 125 or 126 are turned on, the shift input shaft 78 is rotated to change or adjust the traveling speed.

As shown in FIGS. 16 to 19, in the working vehicle having the speed change member 25 and the steering member 28, other wheels such as the traveling crawler 2 and a multi-wheel structure such as four wheels or six wheels can be used as the traveling member. 16 in FIG. 16 and FIG.
In the case of a working vehicle having a wheel structure, a pair of right and left traveling members, a front wheel 127 and a rear wheel 128, are provided on both front and rear sides of the vehicle body 3a.
The steering handle 19 and the main and auxiliary transmission levers 69, 70, the driver's seat 20, the engine 2
1, a transmission case 22 and the like are provided on the vehicle body 1, and a cultivator 129 is mounted on the rear side of the vehicle body 3a so as to be able to move up and down. And sprocket 1
29, and the sprocket 130 provided on the front axle 127a of the front wheel 127 is connected to the sprocket 129 of the rear wheel 128 via the load chain 130a. Approximately the same speed as the rear wheel 128 (or the front wheel 12
7 is driven at a slightly higher speed.

In the case of the work vehicle having the six-wheel structure shown in FIGS. 18 and 19, a pair of right and left traveling members, a front wheel 131, a rear wheel 132, and a middle wheel, are provided on both sides of the front and rear portions and the middle portion of the vehicle body 3a. 133, the steering handle 19, the main shift lever 69, the driver's seat 20, the engine 21,
The transmission case 22 and the like are provided on the vehicle body 3a, and the left and right carrier shafts (axles) 40 of the transmission case 22 are connected to the front wheels 1 via sprockets 134 and 135 and chains 136.
31 and the sprocket 137.1
38 and a rear wheel 132 via a chain 139.
a, and an intermediate shaft 133a of an intermediate wheel 133 is connected to the front axle 131a via sprockets 140 and 141 and a chain 142, so that the front wheel 131, The rear wheel 132 and the intermediate wheel 133 are configured to be driven at substantially the same speed.

As described above, the speed change and steering members 25 and 28 and the speed change and steering mechanisms 81 and 82 of this embodiment are not only the traveling crawler 2 but also the four wheels 127 and 128 or the six wheels 131 and 13.
This is effectively used for a work vehicle having a multi-wheel structure such as 2.133. When turning the steering handles 19 / 19a while operating the main transmission lever 69, the operation of the steering handles 19 / 19a is performed. The speed of the steering member 28 is controlled in proportion to the speed, and the speed of the transmission member 25 is controlled to be decelerated, so that the aircraft can be turned well, and the amount of operation of the steering handles 19 and 19a with respect to the operation of the main transmission lever 69. Is constant,
Even if the vehicle speed is changed, the traveling crawler 2 and the wheel 1 inside the turn
Speed of 27/128, 131/132/133 and traveling crawler 2 outside turning, wheels 127/128, 131.1
The turning with the turning radius kept constant can be performed while keeping the ratio with the speed of 32.133 constant.

[0032]

As is apparent from the above embodiments, the present invention transmits the straight and turning driving forces of the hydraulic continuously variable transmission member 25 and the steering member 28 to the left and right traveling members 2 via the left and right planetary gear mechanisms 35. In a working vehicle that performs straight running and turning traveling of the airframe, a hydraulic continuously variable transmission member 25 and a hydraulic continuously variable steering member 28 are disposed on the opposite side surface of the transmission case 22, and the continuously variable transmission members 25 and Since the left and right traveling members 2 are arranged to be wrapped under the steering member 28, the hydraulic continuously variable transmission member 25 and The steering member 28 can be mounted compactly on the transmission case 22 to easily reduce the size and weight of the fuselage and improve the left-right balance.

Further, there is provided between the main transmission lever 69 and the steering handle 19 and the hydraulic stepless transmission member 25 and the steering member 28 to control the output of the transmission member 25 and the steering member 28. Since the steering mechanisms 93 and 98 are disposed below the step 118 in front of the driver's seat 20, the driver's seat 2
The shift and steering mechanisms 93 and 98 are effectively arranged in an extra space formed below the step 118 of 0, and the space in the steering column and the like required for installing these shift and steering mechanisms 93 and 98 is effectively used. Therefore, the size and weight of the body can be easily reduced.

Further, there is provided a shift between the main transmission lever 69 and the steering handle 19 and the hydraulic stepless transmission member 25 and the steering member 28 to control the output of the transmission member 25 and the steering member 28. The vehicle includes steering mechanisms 93 and 98, and the transmission and steering mechanisms 93 and 98 and the transmission mechanisms 25, 28, 32, and 33 are disposed in a single transmission case 122, and the transmission and steering mechanisms 93 and 98 are provided. And transmission mechanism 25
28 and the transmission case 69 and the steering column 6
The structure and the weight increase due to the separate formation of the gears 7 are eliminated.
33 and rods 108 and 110 serving as a connecting mechanism for them
And the like can be simply incorporated to make it possible to reduce the size and weight of the aircraft easily and at low cost.

[Brief description of the drawings]

FIG. 1 is an overall side view of a combine.

FIG. 2 is an overall plan view of the combine.

FIG. 3 is an explanatory diagram of a mission drive system.

FIG. 4 is a side view of a steering column.

FIG. 5 is a front view of the same.

FIG. 6 is a partial plan view of the same.

FIG. 7 is an explanatory perspective view of a speed change and steering mechanism system.

FIG. 8 is an explanatory front view of a transmission case.

FIG. 9 is an explanatory front view of a transmission case.

FIG. 10 is an explanatory side view of installing a steering case.

FIG. 11 is an explanatory plan view of the installation of a steering case.

FIG. 12 is an explanatory side view of the transmission case.

FIG. 13 is an explanatory front view of a transmission case.

FIG. 14 is an explanatory view of a lever-type handle.

FIG. 15 is an explanatory side view of a driving operation unit.

FIG. 16 is a side view of the four-wheel working vehicle.

FIG. 17 is an explanatory view of a mission drive system of the four-wheel working vehicle.

FIG. 18 is a side view of a six-wheel working vehicle.

FIG. 19 is an explanatory diagram of a mission drive system of a six-wheel working vehicle.

[Explanation of symbols]

 Reference Signs List 2 traveling crawler (traveling member) 19 steering handle 19a lever-type handle 20 driver's seat 22 transmission case 25 transmission member (mission mechanism) 28 steering member (mission mechanism) 32 auxiliary transmission mechanism (mission mechanism) 33 differential mechanism (mission) 35) planetary gear mechanism 69 main transmission lever 93 steering mechanism 98 transmission mechanism 118 step 122 operating case 127 front wheel (traveling member) 128 rear wheel (traveling member) 131 front wheel (traveling member) 132 rear wheel (traveling member) 133 intermediate Wheel (running member)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B62D 11/18 B62D 11/18 49/00 49/00 EK F16H 47/04 F16H 47/04 A F term (Reference) 2B074 AA01 AC02 BA03 BA08 CD08 CH01 DA02 DA03 DB03 DC01 DD01 DE03 DE07 GE05 2B076 AA03 BA03 BB03 CD01 DA03 DB08 3D042 AA06 AB12 BA02 BA04 BA13 BA20 3D052 AA16 DD03 DD04 EE01 FF01 GG03 HH01 HH02JJ

Claims (3)

[Claims] 1. A work vehicle for performing a straight running and a turning movement of an airframe by transmitting a straight running and a turning driving force of a hydraulic continuously variable transmission member and a steering member to a left and right running member via a left and right planetary gear mechanism. A hydraulic continuously variable transmission member and a hydraulic continuously variable steering member are provided on opposite side surfaces, and the left and right traveling members are arranged to be wrapped under the continuously variable transmission member and the steering member. A featured work vehicle. 2. A shift and steering mechanism interposed between a main shift lever and a steering handle and a hydraulic stepless shift member and a steering member to control the output of the shift member and the steering member is provided in a driver's seat. A work vehicle, which is disposed below a front step. A transmission and steering mechanism interposed between the main transmission lever and the steering handle and the hydraulic stepless transmission member and the steering member to control the output of the transmission member and the steering member;
A work vehicle comprising: a shift and steering mechanism and a transmission mechanism arranged in a single shift case; and the shift and steering mechanism and the transmission mechanism are connected in the shift case.