JP2003207021A - Working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve speed changing precision by implementing smooth speed changing by bringing a shaft 84 to pivotally support speed change gears 87, 88 into a free rotating state by disengaging a clutch 116 at the time of speed change operation and certainly cutting off transmission driving force regardless of the speed change state (forward, neutral, backward). <P>SOLUTION: This working vehicle comprises: a complex speed change mechanism 115 forming composite output of a hydraulic speed change mechanism 57 and a planetary gear mechanism 83 to transmit driving force of an engine 2; a composite output speed change mechanism 4a to change speed of the composite output in multiple stages; and a clutch 116 interposed between the complex and composite output speed change mechanisms 115, 4a. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work vehicle such as a rice transplanter, a tractor, a combine, or a civil construction machine, which is equipped with a seedling mount and a nail for planting seedlings to continuously perform seedling work.

[0002]

SUMMARY OF THE INVENTION In a configuration in which a composite output unit of a composite transmission mechanism and an input unit of the composite output transmission mechanism are directly connected by a single transmission shaft, a plurality of splines are provided by the composite output transmission mechanism. In the case of a gear type that shifts by meshing, there is a problem that smooth gear shifting becomes difficult due to poor meshing of the shift gears when the spline phases do not mesh and a gear noise is generated.

[0003]

SUMMARY OF THE INVENTION Therefore, according to the present invention, there is provided a composite transmission mechanism for forming a composite output of a hydraulic transmission mechanism for transmitting a driving force of an engine and a planetary gear mechanism, and a composite output for shifting the composite output in multiple stages. A transmission mechanism is provided, and a clutch is provided between the composite and combined output transmission mechanisms.
The clutch that is disengaged during gear shifting allows the shaft that pivotally supports the gear to freely rotate, enabling smooth gear shifting and ensuring reliable gear shifting regardless of gear shifting (forward, neutral, or reverse). The transmission driving force is cut off to improve the shift accuracy.

Further, the composite output speed change mechanism is provided with a speed change mechanism for changing the speed by switching two spline fitting members integrally connected to each other, and a loose fitting portion for avoiding the engagement of the spline fitting members is provided in the spline member. It was provided,
When the two spline fitting members are integrally operated to shift the phase between one or both of the spline fitting members and the spline member engaged with the spline fitting member when shifting the gear, for example, from reverse to neutral This makes it possible to easily perform smooth gear shifts that are not related to each other and improve gear shift operability.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. 1 is a side view of the whole, FIG. 2 is a plan view of the same, FIG. 3 is a side view of a vehicle body frame, and FIG. 4 is a plan view of the same. In FIG. 1, 1 is a traveling vehicle on which an operator rides, and an engine 2 is installed. It is mounted on the vehicle body frame 3, and the front wheel 6 for traveling paddy fields is supported to the side of the mission case 4 via the front axle case 5, and the rear axle case 7 behind the mission case 4 supports rear wheels 8 for traveling paddy field. The spare seedling mounts 10 are attached to both sides of the bonnet 9 that covers the engine 2 and the like, and the mission case 4 and the like are covered by a vehicle body cover 11 on which an operator rides.
A driver's seat 13 is attached via a steering wheel 14, and a steering handle 14 is provided in front of the driver's seat 13 at the rear part of the hood 9.

Reference numeral 15 in the drawing denotes a seedling mount 16 for planting 5 rows.
In addition, a planting section 20 is provided with a plurality of seedling planting claws 17 and the like.
A rotary case 21 that is slidably reciprocated in the left and right directions and that is rotated at a constant speed in one direction is supported by the planting case 20, and a pair of claw cases 22 are provided at symmetrical positions with respect to the rotation axis of the case 21. 22 is provided and the claw case 22
・ Attach nails 17 with seedlings to the tip of 22.

The hitch bracket 23 on the front side of the planting case 20 is connected to the top link 24 and the lower link 25.
Is connected to the rear side of the traveling vehicle 1 via a lifting link mechanism 26 including a hydraulic lifting cylinder 27 that raises and lowers the planting part 15 via the link mechanism 26, is connected to the lower link 25, and the front and rear wheels 6 and 8 are connected. At the same time as the vehicle is driven and moved, the seedlings for one plant are taken out by the planting claws 17 from the seedling mounting table 16 that slides back and forth to the left and right, and the rice planting work for continuously planting seedlings is performed.

Further, in the figure, 28 is a main gear shift lever, 29 is a planting operation lever for raising and lowering the planting section 15, turning on and off the planting clutch, and operating a marker, 30 is a brake pedal, 31 is a speed change pedal, and 32 is A diff lock pedal, 33 is a sensitivity adjusting lever, 34 is a stop lever for stopping the planting portion 15 at an arbitrary height position, 35 is a unit clutch lever 35, and a shift and elevating lever 2 is provided near the steering handlebar 14 position.
8 and 29, brakes and speed change pedals 30 and 31, and sensitivity adjustment and stop and unit clutch levers 33, 34, and 35 are provided near the position of the driver's seat 13.

Further, in the figure, 36 is a center float for leveling one line, 37 is a side float for leveling two lines, 38 is a fertilizer in a fertilizer hopper 39, and a flexible transfer hose 41 is fed by a blower wind of a blower 40. It is a side-row fertilizer applicator for 5 rows which is discharged to the side-row grooving device 42 of the floats 36, 37 via the.

As shown in FIGS. 3 to 5, the vehicle body frame 3 is divided into a front frame 43, an intermediate frame 44, and a rear frame 45, and a pair of left and right front frames 43 is formed.
The front axle case 5 on the pair of left and right intermediate frames 44, the rear axle case 7 on the pair of left and right rear frames 45, the fuel tank 46 for supplying fuel to the engine 2, and the like.
The front frame 47 and the base frame 48 are connected to the front side and the middle of the to form a quadrangular frame in plan view.
The engine 2 is mounted on the base plate 9 and the base frame 48 via a vibration-proof rubber.

Further, as shown in FIG. 10, the gates are formed by connecting the intermediate rising portions 50 of the rear frame 45 substantially parallel to each other by the pipe frame 51 and the gate frame 52, and fixing the left and right lower ends to the rear axle case 7. Shaped frame 53
The rear ends are integrally connected, and the fuel tank 46 is disposed between the left and right rising portions 50.

Further, the front and rear ends of the left and right intermediate frame 44 are detachably fixed to the rear end of the front frame 43 and the front end of the rear frame 45 via bolts 54, and left and right are attached to the lower surface of the left and right intermediate frame 44 via bolts 55. The front axle case 5 is detachably fixed and the left and right front axle cases 5 are connected and fixed to the mission case 4.

As shown in FIGS. 6 to 10, a power steering case 56 is provided on the left side of the front surface of the mission case 4.
And a continuously variable hydraulic speed change mechanism 57 is provided on the right side of the case 4, the speed change input pump shaft 58 of the hydraulic speed change mechanism 57 is projected in the front direction of the vehicle body, and is pumped to the transmission shaft 59 in the front-rear direction below the engine 2. The shaft 58 is connected and the engine 2
To the output shaft 60 of the transmission shaft 59 via the transmission belt 61.
And the output of the engine 2 is transmitted to the hydraulic speed change mechanism 57.

Further, the mission case 4 and the rear axle case 7 are integrally connected by a pipe-shaped connecting frame 62 on the center line in the front-rear direction of the vehicle body, and the rear output shaft 63 and the PTO output shaft 64 are provided behind the mission case 4.
Of the rear output shaft 6 via the rear transmission shaft 66 to the rear input shaft 65 that projects the front end of the rear axle case 7.
3 are connected and power is transmitted from the traveling output shaft 63 to the left and right rear wheels 8. Further, the PTO is mounted on an intermediate shaft 68 provided on a bearing 67 above the rear axle case 7 via a universal joint shaft 69.
The output shaft 64 is connected, the center shaft 68 is connected to the input shaft of the planting case 20 via a universal joint shaft, and power is transmitted from the PTO output shaft 64 to the planting unit 15.

Further, as shown in FIGS. 11 to 16, the mission case 4 includes a main body portion 70 and a front lid portion 71.
And a rear lid portion 72, and each lid portion 7 is provided in front of and behind the body portion 70.
1 and 72 are detachably fixed by bolts to form a closed box shape, and a partition wall portion 73 that divides the inside of the body portion 70 into front and rear is provided. Further, the hydraulic transmission mechanism 57 is attached to the front surface of the front lid portion 71, a transmission shaft 74 having a small diameter is engaged with the pump shaft 58 projecting into the transmission case 4, and the transmission gear 74 is bearing-bearing to the front lid portion 71. Then, the power of the transmission gear 74 is transmitted to the charge pump 75 fixed to the rear surface of the rear lid portion 72 via the pipe shaft 76.

Further, the sun gear 78 is engaged with the motor shaft 77 of the hydraulic speed change mechanism 57 projecting into the transmission case 4, the sun gear 78 is bearing-supported on the front lid portion 71, and the transmission gear of the small diameter is used. A large-diameter carrier gear 79 is always meshed with 74, and the carrier gear 79 is rotatably supported on the boss portion of the sun gear 78. Three planetary gears 80 are rotatably provided on the carrier gear 79 via a shaft 81. A ring gear 82 that meshes with the planetary gear 80 is provided, and a ring gear 82 that meshes with the planetary gear 80 is provided, and a planetary gear mechanism 83 is formed by the gears 78, 80, and 82.

The sun gear 78 and the rear cover 72 rotatably support the front and rear of the combined output shaft 84, and the ring gear 82 is supported by the combined output shaft 84 so as to engage with the combined output shaft 84. Forward and reverse rotation outputs that are continuously variable hydraulic shift outputs of the hydraulic pump 85 and the hydraulic motor 86, and the transmission gear 74.
And the decelerated rotation output (constant rotation in one direction) of the carrier gear 79 are combined by the differential action of the planetary gear mechanism 83 and transmitted to the combined output shaft 84 as a unidirectional rotational force of zero to maximum speed.

Further, the forward gear 8 is attached to the composite output shaft 84.
7 and the reverse gear 88 are supported as idle shafts, and the gears 87 and 88 are selectively engaged with the composite output shaft 84 by the slider 89 to switch to forward, neutral or reverse output, and the partition wall portion 73 and rear The rear output shaft 63 is attached to the lid 72.
Bearings. Further, a front output shaft 92 that transmits power to the left and right front axles 91 via the differential gear 90,
A counter shaft 94 that supports the PTO speed change gear 93 as an engaging shaft is provided, and the reverse power of the reverse gear 88 is transmitted to the rear and front output shafts 63 and 92 via the output gears 95 and 96, so that the front and rear wheels 6.8 and 8 are transmitted. The rear drive shaft 63 is driven in reverse, and the rear output shaft 63 is rotatably supported by the movable gear 97 and the planted gear 98.
The auxiliary transmission slider 99 selectively engages the gears 97 and 98 with the rear output shaft 63.

Further, the high speed gear 100 of the counter shaft 94
The forward gear 87 and the moving gear 97 are always meshed with each other via the a.100b, and the counter shaft 94 is used for low speed PTO.
The gears 98 are always meshed with the transmission gears 93, and each gear 1
The power of the forward gear 87 is transmitted to the respective output shafts 63, 92 via 00a, 93, 98 to drive the front and rear wheels 6.8 forward at the seedling planting work speed. Further, both the moving gear 97 and the planting gear 98 are in an idle state, and the PTO output shaft 64 is manually rotated so that the operator can manually rotate the planting claws 17 and the like to remove the stuck seedlings. As well as
The power of the forward gear 87 is transmitted to the output shafts 63 and 92 through the gears 100a and 100b, and the front and rear wheels 6.8 are driven forward at a high moving speed such as road movement between fields.

Further, as shown in FIG. 11, the PTO transmission shaft 1
01 and the power of the PTO speed change gear 93 via the PTO speed change mechanism 102 to drive the planting section 15 to freely change between stocks, and output PTO via the chain 103 installed in the mission case 4. The fertilizer output shaft 104 is connected to the shaft 64, and the fertilizer applicator 38 is driven in synchronization with the planting portion 15. In addition, as shown in FIG. 13, the transmission case 4 is provided with the oil gauge 105, and
As described above, the sliders 89 and 99 are locked to the same shift fork 106, and the forward / backward movement and the auxiliary shift (low / high speed) are switched by switching the shift lever 28 to five positions. Further, as shown in FIGS. 16 and 17, the swash plate 1 of the hydraulic pump 85 is
07 through the control shaft 108 to the hydraulic speed change operation arm 109
Is connected to the arm 109 via the rod 110 via the rod 110, and the arm 111 is provided with a spring 111 for automatically returning the pedal 31 to the stop (zero speed) position when the pedal 31 is released. And the oil damper 112 is connected to the arm 109, and when the foot is released from the pedal 31 which is being depressed,
The resistance of the oil damper 112 and the restoring force of the spring 111 cause the pedal 31 to return at a gentle, substantially constant speed and gradually decrease in speed. Instead of the oil damper 112, a constant speed operation member may be formed by a gas spring or the like.

Further, as shown in FIG. 19, the pedal 31
Pedal 111 by spring 111 while keeping your foot away from
When 1 is returned to the stop (zero speed) position, the sun gear 78 reverses clockwise at the maximum rotation and the planetary gear 8 is rotated.
At the same time as causing 0 to rotate counterclockwise,
Further, by rotating the carrier gear 79 by the transmission gear 74, the planetary gear 80 is caused to perform an operation of revolving in the clockwise direction and rotating in the counterclockwise direction, the rotation of the ring gear 82 is made zero, and the combined output shaft 84 is stopped and maintained. When the pedal 31 is stepped against the spring 111 by the foot, the sun gear 78 stops, the transmission gear 74 rotates the carrier gear 79, and the planetary gear 80 rotates clockwise to revolve in the clockwise direction for transmission. Gear 74
The combined output shaft 84 is rotated by the gear power of
As shown in FIG. 18, the power of the engine 2 is transmitted to the transmission gear 74 and the hydraulic speed change mechanism 57 to be combined and output by the planetary gear mechanism 83.
Shifting is performed, and each of reverse movement, low speed forward movement (running with field planting), and high speed forward movement (road traveling traveling) is performed.

Then, for example, in the conventional hydraulic speed change mechanism 57, the output power P2 is about 70% of the input power P1, whereas, as shown in FIG. 20, a part of the gear transmission power P3 is used when traveling at a low speed. Pump shaft 58 as hydraulic power transmission P4
To increase the output power P2 to about 80% of the input power P1. Further, as shown in FIG. 21, when the vehicle travels at a high speed with the hydraulic transmission power of the hydraulic speed change mechanism 57 being zero (P4 = 0), the hydraulic power loss is eliminated and the output power P2 is approximately 95% of the input power P1.
This enables the highly efficient rotation increased above. For example, as shown in FIG.
22 is changed from -1 to 0 so that the motor shaft 77 is rotated from -1000 to 0 rotation.
When the gear 74 side is rotated 1000 times regardless of the angle of the arm 109 as shown in (2), as shown in FIG.
The gears 74 and 79 and the planetary gear mechanism 83 are composed so that the combined output shaft 84 makes 0 to 1000 rotations with respect to the angle of the arm 109.

Further, the total control range of the arm 109 is
When set to 1 to 0, as shown in FIG.
The low speed (zero speed) side and high speed side control operations of 09 are restricted by bolt type low speed and high speed stoppers 113 and 114.

As is apparent from the above, the hydraulic speed change mechanism 57 for transmitting the driving force of the engine 2 and the planetary gear mechanism 83.
By providing a composite transmission mechanism 115 that forms a composite output of the hydraulic transmission mechanism 57 and rotating the composite output shaft 84 of the composite transmission mechanism 115 in one direction by the reverse rotation output of the hydraulic transmission mechanism 57, the gear shift operation arm 109 having a large operating force From 0 to +1
In the range of -1 to 0 side where the operating force is lighter than the side, the power is transmitted from the synthesizing unit side to the hydraulic pump 85 of the hydraulic speed changing mechanism 57, and the operating force is light regardless of the load of the hydraulic speed changing mechanism 57. By easily changing the speed of the hydraulic speed change mechanism 57,
It is possible to easily secure a continuously variable transmission capable of zero start and high transmission efficiency.

Further, since the output shaft speed of the hydraulic speed change mechanism 57 is set to substantially zero in the maximum rotation state of the combined output shaft 84, the engine 2 is operated when the combined output shaft 84 is in the maximum rotation state.
The driving force from the vehicle can be transmitted to the mission case 4 with maximum efficiency, and the workability can be improved by, for example, enhancing the running performance.

11, FIG. 12, FIG. 16, FIG. 24, FIG.
As also shown in FIG. 5, the ball joint type main clutch 116 is provided between the ring gear 82 and the forward gear 87 of the composite output shaft 84.
The ring gear 82 is rotatably supported by the sleeve 117 that is spline-fitted to the composite output shaft 84, and the ball 119 that is projected into the ball groove 118 on the outer circumference of the sleeve 117 is embedded in the boss portion 82a of the ring gear 82. As shown in FIG. 24, when the ball 119 is pushed by the clutch body 121 which slides on the sleeve 117 by the shift fork 120 to push the ball 119 into the ball groove 118, the main clutch 116 is turned on and the ring gear 82 rotates. 2 to the composite output shaft 84, and
As shown in FIG.
Slide 1 against the clutch spring 122 to make the ball 11
When the 9 is released, the ball 119 is rotated by centrifugal action.
Is disengaged from the ball groove 118 and the main clutch 116 is disengaged, so that power transmission from the ring gear 82 to the combined output shaft 84 is cut off.

As shown in FIGS. 14, 24 and 25, a slider 89 operated by the shift fork 106.
When the reverse position is 99 (the maximum right position in FIG. 24), the combined output shaft 84 and the splines 84a and 88 of the reverse gear 88 are provided.
When the slider 89 and the slider 99 are spline-fitted to the spline 98a of the planted gear 98 and the sliders 89 and 99 are switched from the reverse position to the neutral position (solid line position in FIG. 24), the composite output shaft The slider 89 is attached to the spline 84a of 84, and the planted gear 98
Of the rear output shaft 63 and the slider 99 for engaging the slider 99 with the slider 99 at the time of forward movement when switching from the reverse to the neutral position of the slider 99. In order to avoid the spline fitting (engagement) of the slider 99, the overlapping portion of the spline 63a that interferes with the slider 99 is formed in the circumferential guide portion 63b of the smooth surface, so that it is easy to switch from the backward movement of the slider 89/99 to the neutral position. It is configured so that

As shown in FIG. 26, a backlash is provided between the slider 99 and the rear output shaft 63 which are spline-fitted during forward movement, and the spline 63 of the rear output shaft 63 is provided.
The tooth width c of the spline hole 99a of the slider 99 is formed to be larger than the tooth thickness a of a, and the tooth tip of the spline 63a is formed in the chamfered portion 63b that eliminates the phase shift of the spline. The slider 99 and the rear output shaft 63 are configured to be easily engaged with each other during spline fitting.

As is apparent from the above, the hydraulic speed change mechanism 57 for transmitting the driving force of the engine 2 and the planetary gear mechanism 83.
And a transmission gear mechanism 4a of the transmission case 4 that is a combined output transmission mechanism that shifts the combined output in multiple stages, and provides a combined output between the combined transmission mechanism 115 and the transmission gear mechanism 4a. Since the clutch 116 is provided, the clutch 116 can be operated at the time of gear shift operation.
By turning off, the shaft that pivotally supports the speed change gears 87 and 88 is freely rotated to enable smooth speed change, and reliable transmission is performed regardless of the speed change state (forward, neutral, reverse). It is possible to improve the shift accuracy by cutting off the driving force.

Further, a circumferential guide which is a loose fitting portion which is provided with a gear shifting mechanism for shifting gears by switching between sleeves 89 and 99, which are two spline fitting members to be integrally connected, is a loose fitting portion for avoiding spline engagement of the sleeve 99. By providing the portion 63b on the spline 63a of the rear output shaft 63 which is a spline member, for example, the sleeve 99 and the spline 63a that meshes with the sleeve 99 when shifting is performed from reverse to neutral.
Even if the phases are shifted from each other, it is possible to easily perform a smooth shift change regardless of the phase and improve the shift operability.

As shown in FIGS. 11 and 27, the PTO transmission gears 93 of the counter shaft 94 are 50, 60, 70 and 8.
Stock change gears 93a, 93b, 93c for 0, 90 stocks
The PTO transmission shaft 101 includes inter-strain gears 123a, 123b, 123c, 12 which have 93d, 93e and are always meshed with the gears 93a, 93b, 93c, 93d, 93e.
3d · 123e, PTO speed change shaft 101 is a guide 1
A ball 126 that allows a speed change rod 125 to be slidably inserted in the axial direction around the cylinder axis through the shaft 24 and engages and connects the gears 123a to 123e with the speed change shaft 101, respectively.
By embedding (three gears per gear) in the ball groove 127 of the speed change shaft 101, the large diameter clutch body 128 formed on the speed change rod 125 is moved, and the ball 126 is pressed by the clutch body 128 to select one of the gears 123a to 123e. Of the gear 123a, 123b, 123c, 123d or 12
3e is connected to the speed change shaft 101 so that the speed change shaft 101 is rotated at a predetermined stock speed.

Further, a plurality of detent grooves 130 are formed on the front extension end of the speed change rod 125, and the groove 1 is formed.
The detent ball 131 to be engaged with the compression spring 1
The detent portion 133 is formed inside the transmission case 4 via 32, and the shift rod 125 is positioned by engaging the detent groove 130 and the ball 131. The detent portion 133 is coaxial with the shift shaft 124. By directly providing the shift rod 125, it is possible to reliably fix the position of the speed change rod 125 with a simple structure having a small number of parts.

Further, the inter-stock gears 123a to 123e
An overstroke preventing ball 134 is enclosed between the outermost speed change shaft 101 and the speed change rod 125 via a gear collar 135 and an inter-stock transmission gear 136, so that the speed change rod 126 moves in an overstroke state in which the movement exceeds a predetermined value. At this time, the clutch body 128 is brought into contact with the ball 134 to prevent the shift rod 126 from overstroke. In this case, it is possible to compactly incorporate it into the speed change shaft 101 and simplify the structure and reduce the cost without separately providing a dedicated overstroke stopping member.

As shown in FIG. 28, the periphery of the planetary gear mechanism 83 of the front cover 71 of the mission case 4 is surrounded by the front cover 71.
It is surrounded by the peripheral side wall 71a and the rib 137 which is erected from the inner side wall to suppress the agitation of the oil in the mission case 4 by the planetary gear mechanism 83 to a small amount, thereby suppressing the oil temperature from rising and improving the heat balance. It is configured to let.

As shown in FIG. 29, a breather 139 arranged at the lower right of the driver's seat 13 is connected to an elbow pipe 138 at the upper rear side of the mission case 4 via a flexible resin pipe 140. The breather 139 is connected to the vertical frame to form the mission case 4
Steps on the vehicle body cover 11 above the upper surface (underfoot)
By disposing the breather 139 above the position 11a, the oil in the mission case 4 is prevented from leaking from the breather 139, and the step 11a
It is configured to surely prevent the above muddy water from entering through the breather 139. The breather 139 may be attached to any of the portal frame 52, the right rear frame 45, and other members.

[0036]

As is apparent from the above embodiments, the present invention provides a combined transmission mechanism 115 for forming a combined output of the hydraulic transmission mechanism 57 for transmitting the driving force of the engine 2 and the planetary gear mechanism 83, and the combined output. A composite output transmission mechanism 4a for shifting in multiple stages is provided, and a composite and composite output transmission mechanism 11 is provided.
Since the clutch 116 is provided between the gears 5 and 4a, the clutch 116 is disengaged during the gear shifting operation to bring the shaft 84 pivotally supporting the gear shift gears 87 and 88 into a free-rotating state so that smooth gear shifting is possible. It is possible to improve the gear shifting accuracy by reliably interrupting the transmission driving force regardless of the gear shifting state (forward, neutral, reverse).

Further, the composite output speed change mechanism 4a is provided with a speed change mechanism for changing the speed by switching between the two spline fitting members 89 and 99 that are integrally connected to each other, and a loose fit for avoiding the engagement of the spline fitting member 99. Since the portion 63b is provided on the spline member 63a, the two spline fitting members 89 and 99 are integrally operated so that either one or both of the spline fitting members 99 can be operated at the time of gear shifting, for example, from reverse to neutral. Spline member 6 that meshes with this
Even when the phase is different from that of 3a, it is possible to easily enable smooth gear shift regardless of the phase and improve the gear shift operability.

[Brief description of 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 traveling vehicle body.

FIG. 4 is a plan view of a traveling vehicle body.

FIG. 5 is a side view of a body frame.

FIG. 6 is a side view illustrating a drive unit.

FIG. 7 is an explanatory plan view of a drive unit.

FIG. 8 is a side view illustrating a side clutch operation system.

FIG. 9 is an explanatory plan view of a side clutch operation system.

FIG. 10 is an explanatory perspective view of a vehicle body.

FIG. 11 is a sectional view of a mission case.

FIG. 12 is an explanatory view of the traveling drive unit.

FIG. 13 is an explanatory diagram of a planetary gear mechanism.

FIG. 14 is a partial view of a mission case.

FIG. 15 is a sectional view of the planetary gear mechanism.

FIG. 16 is an explanatory diagram of a gear arrangement of a mission case.

FIG. 17 is a side view of a hydraulic speed change operation arm unit.

FIG. 18 is an output explanatory diagram of the engine.

FIG. 19 is a rotation explanatory view of the planetary gear mechanism.

FIG. 20 is an explanatory diagram of engine output during low speed traveling.

FIG. 21 is an explanatory diagram of engine output during high-speed traveling.

FIG. 22 is an output explanatory diagram.

FIG. 23 is an output explanatory diagram of a composite output shaft.

FIG. 24 is an explanatory diagram of a clutch unit.

FIG. 25 is an explanatory diagram of a clutch unit.

FIG. 26 is an explanatory diagram of a spline section.

FIG. 27 is an explanatory diagram of a shift shaft portion.

FIG. 28 is an explanatory diagram of a front lid portion.

FIG. 29 is an explanatory view of the arrangement of a breather section.

[Explanation of symbols]

2 engine 4a gear mechanism 57 Hydraulic transmission 63a Spline (Spline member) 63b Guide part (free fitting part) 83 Planetary gear mechanism 89 Sleeve (Spline fitting member) 99 Sleeve (Spline fitting member) 115 Compound transmission 116 clutch

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3D039 AA02 AA03 AA04 AA07 AA25                       AA32 AB12 AB13 AB14 AC04                       AC33 AC37 AC39 AC45 AD24                 3J067 AA01 AB01 AC05 AC42 AC51                       BA13 EA33 FB61 GA13 GA14

Claims (2)

[Claims] 1. A composite transmission mechanism for forming a composite output of a hydraulic transmission mechanism for transmitting a driving force of an engine and a planetary gear mechanism, and a composite output transmission mechanism for shifting the composite output in multiple stages, and the composite and composite. A work vehicle in which a clutch is provided between the output speed change mechanisms. 2. A composite output speed change mechanism, which is integrally connected 2
2. The work vehicle according to claim 1, wherein a shift change mechanism for shifting the speed by switching between two spline fitting members is provided, and a free fitting portion for avoiding engagement of the spline fitting members is provided on the spline member. .