JPH0544181Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to a continuously variable transmission device for a rice transplanter.

(Prior Art) In the case of a conventional riding rice transplanter, the planting part is towed by the passenger vehicle body, and when turning, the steering wheel and handbrake are operated to turn.

(Problems to be Solved by the Invention) In the conventional vehicle as described above, when turning by operating the steering wheel and handbrake, one of the front and rear wheels slips due to a discrepancy in the rotational speed of the front and rear wheels.

This causes the wheels to lift mud and disturb the field. Therefore, it has the disadvantage of interfering with planting on headlands.

To this end, Japanese Patent Application Laid-Open No. 60-203534 proposes a system in which the speed of the rear wheels is changed by operating a turning operation tool.

However, the front wheel speed reduction device and the rear wheel speed change device are configured separately, and if the front wheels are rotating at high speed, even if the rear wheels are shifted, the rear wheels will not be able to follow the front wheels and will reach a dangerous speed. Circling may occur.

(Means for solving the problem) Therefore, the technical problem of this project is to create a rice transplanter that can make smooth turns without danger, and this project aims to solve this technical problem. The technical means is to directly extend a continuously variable transmission consisting of a pulley and a belt between the prime mover and the common drive shaft of the front and rear wheels, and to connect the belt to the low speed side of the continuously variable transmission. This is a continuously variable transmission device for a rice transplanter, in which a rotation operating tool is connected to the rice transplanter, and a rear wheel reduction device and a front wheel speed doubler of the transmission, which are operated in conjunction with the rotation operating tool, are connected to the common drive shaft. .

(Effect of the invention) According to this technical means, a continuously variable transmission is mounted on a common drive shaft for the front and rear wheels that is directly driven from the prime mover side, without using separate transmissions for the front and rear wheels. Since the common drive shaft is continuously variable to the low speed side using the turning operation tool, the front wheel speed doubler or rear wheel deceleration device of the transmission is guided to the low speed side, so even if the front wheels are doubled at high speed. Basically, the front and rear wheels shift to a low speed side with a continuously variable transmission, and the transmission on the transmission side further reduces the speed, so there is no danger when turning, and the low speed mechanism is continuously variable. There is no rapid gear change, and smooth turns can be made without disturbing the field.

In addition, row alignment at the start of planting in the next step can be easily performed.

The above points are effects achieved because the continuously variable transmission is located not on the transmission side but on the prime mover side.

(Example) The embodiments shown in the drawings will be described below.

First, the riding rice transplanter will be described in its entirety. Reference numeral 1 denotes a riding vehicle body, and a planting unit 3 is connected to the rear of this riding vehicle body 1 via a lift mechanism 2.

An engine 5 is mounted on a vehicle body frame 4, and front wheels 6 are located below the engine 5. Reference numeral 7 denotes a transmission case, and there is a transmission case 8 on both left and right sides of the transmission case 7, and a rear wheel 9 is provided at the rear end of the transmission case 8.

10 is a driver's seat, 11 is a footrest, and 12 is a steering wheel.

A top link 13 and a lower link 14 of a link frame are attached to the lift mechanism 2, and the planting part 3 is raised and lowered by swinging the links 13 and 14 by expansion and contraction of a hydraulic cylinder.
The planting section 3 consists of a seedling stand 15, a float 16, and a transmission case 17. Further, 18 is a rotary case, and 19 is a planting arm.

The above-mentioned transmission device will be explained based on FIG. 2.
A pulley 22 is driven via the hydraulic pump 2
3 is driven.

This hydraulic pump 23 is used to send hydraulic oil to the elevating and lowering parts of the planting section.

A split pulley 25 is also provided on the shaft 24 of the pulley 22, and a split pulley 27 is driven via these belts 26.

The split pulley 27 also drives the front and rear common drive shafts 29 and 30 by means of a gear mechanism within the transmission case 7 via the main clutch 28 . In addition, 30 shows a planting drive shaft.

A gear 31 driven by a gear mechanism in the transmission case 7 drives a propeller shaft 32, and the front wheels 6 and rear wheels 9 are driven via differential gear mechanisms 33 and 34 in the differential case.

35 indicates a gear mechanism within the transmission case 8 for rear wheel drive. 36 and 37 are drive shafts for the front wheels and rear wheels.

The present invention is a rice transplanter as described above, in which the continuously variable transmissions 25, 26, and 27 are configured to be able to shift to a lower speed side in relation to decelerating the rear wheels or doubling the speed of the front wheels when turning.

Now, a mechanism for shifting the continuously variable transmission to a lower speed side in conjunction with a turning operating tool such as a steering wheel or a brake pedal will be explained.

The split pulley 25 shown in FIG. 3 is the fixed side V pulley 2.
5a and a moving side pulley 25b, and the split pulley 27 consists of a fixed side V pulley 27a and a moving side V pulley 27a.
The movable V-pulley 27b is always connected to the fixed V-pulley 2 by a spring 53.
It is energized towards 7a.

And the brake pedal 54 and the cam lever 38
are interlocked and connected by a link mechanism. in this case,
Of course, the brake pedal 54 operates the brake via a rod (not shown). The cam consists of a fixed cam 40 and a rotating cam 39, and the rotating cam 39 moves the moving side V-pulley 25b.
It is designed to slide.

Therefore, when you step on the brake pedal 54 for turning, the brake is applied as usual, and the rotating cam 3
9 rotates, the movable side V pulley 25b moves, and the belt 26 shifts to the low speed side. The one shown has one brake pedal, but there are actually two on the left and right, and the rotary cam is operated by operating either one of them. In conjunction with this, the movable V-pulley 27b is also moved to the right by the force of the spring 53, and the belt 26 begins to transmit at a low speed.

Thus, the common drive shaft 29 for the front and rear wheels in the transmission rotates at a low speed.

Furthermore, by operating the steering wheel 41 shown in FIG.
3 to steer the front wheels 6, operate the fork 46 from the lever 44 of the yoke 43 via the link mechanism 45, and operate the high-speed gear 47 that is constantly meshing with the gear 31 that transmits power to the front wheels. Remove the gear 48 on the low speed side from the shaft 32 that drives the front wheel of the gear 31.
The shaft 50 is rotated at low speed by meshing with the upper gear 49.

In this case, from gear 47 to gear 48 as shown in FIG.
By separating the gear 48 and connecting the shaft 50 with a one-way clutch 51, the high-speed gear 4 is always connected.
7, the shaft 50 is rotated at high speed by overcoming the one-way clutch 51, but if the high-speed gear 47 is disconnected from the shaft 50 by the clutch mechanism 52, the one-way clutch 51 causes the shaft 50 to rotate at a low speed by the gear 48. .

Using a one-way clutch like this,
Since there is no neutral position, there is no shock when switching.

In this way, in conjunction with the turning operation tool, the continuously variable transmission on the side above the transmission on the prime mover side shifts to the low speed side, and then the gear transmission mechanism inside the transmission case causes the rear wheels to rotate at an even lower speed.

Figure 6 shows the case of increasing the speed of the front wheels, and the split pulley 2
The period between 5 and 27 is similar to that of the first embodiment, and the continuously variable transmission shifts to the low speed side in conjunction with a turning operation tool, for example, a brake pedal. The front wheels then increase speed using a gear transmission mechanism inside the transmission case.

That is, the gear 49 and the gear 48 are always meshed and the shaft 32 is rotated at low speed by the one-way clutch 51, but as in the first embodiment, the clutch 52 is moved by operating the steering wheel, and the gear 47 on the high speed side is rotated as the shaft. Gears 31 and 47 are directly connected to 32.
This meshing overcomes the one-way clutch and causes the shaft 32 to rotate at an increased speed. Note that 53 in the figure indicates a brake.

In the above explanation, we have explained the case where the rear wheel deceleration during a mission and the deceleration by continuously variable speed on the side above the transmission on the prime mover side are controlled by different turning operating tools, but the same turning operating tool can be used to control the continuously variable speed reduction. It is also possible to link the deceleration of the rear wheels during transmission with the deceleration of the rear wheels during transmission.For example, a link or wire is stretched between the yoke of the steering wheel and the drive side split pulley of the continuously variable transmission. The forks that reduce the speed of the transmission and move the switching gear in the transmission may be interlocked with the yoke of the steering wheel by a link or wire. In addition to the steering wheel, interlocking with the turning operation tool may also include interlocking with brake pedals, power steering, and the like. In addition to wires and links, they can also be interlocked by electrical connections.

As described above, by configuring the continuously variable transmission to be guided to the low speed side in relation to rear wheel deceleration or front wheel doubling during turning, smooth turning can be achieved.

[Brief explanation of the drawing]

Figure 1 is an overall front view of the rice transplanter, Figure 2 is an explanatory diagram of the transmission device, Figure 3 A and B are explanatory diagrams of the continuously variable transmission, and Figure 4 is an explanatory diagram of rear wheel deceleration using the steering wheel. FIG. 5 is a diagram of an embodiment different from FIG. 4,
FIG. 6 is an explanatory diagram in the case of increasing speed of the front wheels. DESCRIPTION OF SYMBOLS 1... Passenger vehicle body, 2... Lift mechanism, 3... Planting part, 4... Vehicle body frame, 5... Engine, 6
...Front wheel, 7...Mission case, 8...Transmission case, 9...Rear wheel, 20, 22...Pulley, 2
1...Belt, 24...Shaft, 25, 27...Split pulley, 26...Belt, 32...Propeller shaft, 5
4... Brake pedal, 41... Steering wheel.

Claims (1)

[Scope of utility model registration request] A turning operation tool that directly extends a continuously variable transmission consisting of a pulley and a belt between a prime mover side and a common drive shaft for front wheels and rear wheels, and causes the continuously variable transmission to move the belt to a low speed side. A continuously variable transmission device for a rice transplanter, in which a rear wheel reduction device and a front wheel speed doubler device of a transmission, which are operated in conjunction with the turning operation tool, are connected to the common drive shaft.