JPH0627460Y2 - Four-wheel drive type rice transplanter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a structure of a traveling transmission system in a four-wheel drive type rice transplanter.

[Conventional technology]

In the four-wheel drive type rice transplanter, the speed change system is configured such that the drive speed of the front wheels and the drive speed of the rear wheels are substantially equal.

[Problems to be solved by the device]

When turning in a general four-wheeled vehicle, the turning radius of the front wheels becomes larger than the turning radius of the rear wheels, and so-called a difference between the inner and outer wheels occurs. Therefore, in order for the four-wheel drive vehicle to smoothly turn, it is preferable to generate a driving speed difference between the front wheels and the rear wheels according to the difference between the inner and outer wheels when turning.

In the riding-type rice transplanter, when one planting process is completed and reaches a ridge, the riding type rice transplanter turns at this ridge and shifts to the next planting process. In this case, one of the rear wheels is braked by the side brake when turning at the edge of the ridge, so that a small turn can be made even at a narrow edge. In this way, you can make a small turn by braking one rear wheel when turning,
At that time, the difference between the inner and outer wheels becomes large near the length of the wheel base of the aircraft.

However, when the driving speeds of the front wheels and the rear wheels are substantially equal to each other as in the conventional configuration, the driving speed of the front wheels becomes too slower than the turning speed of the front part of the machine body, and the front wheels slip. Occurs.

In the case of a riding-type rice transplanter that runs on a paddy field with high running resistance,
The front and rear wheels are equipped with lugs that transmit the propulsive force to the paddy field.However, the lugs on the front wheels are generally different from those on the rear wheels in terms of steering operation of the front wheels when driving on the road and preventing the propagation of vibration from the front wheels to the engine. It is set smaller than the rug. As a result, the aircraft mainly advances due to the propulsive force of the rear wheels with large lugs in the paddy field, and even when the vehicle turns at the edge, the aircraft will turn based on the drive speed of the rear wheels. Therefore, the front wheels driven at the same speed as the rear wheels are in a state of being too slow with respect to the front portion of the vehicle body that is turning faster than the rear portion of the vehicle body due to the size of the turning radius.

When the front wheel slips when turning at the edge as described above, the front wheel may damage the rice field near the edge, or the waves generated by the front wheel may tilt the seedlings that have already been planted.

An object of the present invention is to prevent a rice paddy plant of four-wheel drive type from preventing the paddy field from becoming rough and the seedling to be tilted at the time of turning at a ridge.

[Means for Solving the Problems]

A feature of the present invention is that the four-wheel drive type riding rice transplanter as described above is configured as follows.

The rear wheel transmission is equipped with a rear wheel transmission capable of switching between a standard driving state in which the driving speeds of the front wheels and the rear wheels are substantially equal to each other and a rear wheel deceleration state in which the driving speed of the rear wheels is reduced from the driving speed of the front wheels. An actuator for locking the front wheel differential mechanism of the front wheels is provided in conjunction with the switching operation to the rear wheel deceleration side.

[Action]

(I) With the configuration according to the present invention, it is sufficient to switch the rear wheel transmission to the rear wheel decelerating state at the time of turning at the ridge.

As a result, the drive speed of the rear wheels will be slower than the drive speed of the front wheels, so if the aircraft turns based on the drive speed of the rear wheels, it will turn faster than the rear of the aircraft due to the size of the turning radius. The turning speed of the front part will also be reduced, and the difference between the driving speed of the front wheels (higher than the driving speed of the rear wheels) and the turning speed of the front part of the aircraft will be smaller than in the conventional configuration, and the front wheels will slip. Phenomenon decreases.

(Ii) In this case, it is conceivable to drive the front wheels to the rear wheels at an increased speed when turning at the ridge, but since the front wheels are driven at a high speed in this way, the turning speed of the entire aircraft also becomes faster. It is not preferable in terms of stability of the airframe when turning in a soft paddy field.

On the other hand, like the present invention, if the rear wheels are decelerated with respect to the front wheels when turning at the edge of the ridge, the turning speed of the entire aircraft will also decrease, so the stability of the aircraft during turning in a weak paddy field. Will be good.

(Iii) When braking the inner rear wheel with the side brakes when turning at the edge of the ridge, the turning radius of the aircraft becomes very small, pushing the mud on the side of the steered front wheel, The aircraft will turn. in this case,
The outer front wheel, which has a larger turning radius than the inner front wheel, is more susceptible to the mud resistance.Therefore, when the outer front wheel receives the mud resistance strongly, the outer front wheel stops due to the action of the front wheel differential mechanism, and the inner front wheel stops. The front wheels of the car will spin at high speed.

In such a situation, the inner front wheel that idles will dig a groove on the rice field near the ridge. In addition, since the propulsive force of the left and right front wheels will also decrease, the strong propulsive force of the rear wheels will cause the aircraft to go straight without turning, and after that, in order to correct the orientation of the aircraft, steer the front wheels largely A situation occurs in which the rice field is damaged.

Therefore, by locking the front wheel differential mechanism in conjunction with the switching operation to the rear wheel deceleration state as in the present invention, the left and right front wheels are constantly driven at the same speed, and the outer front wheels are stopped. Also, high speed idling of the inner front wheels is prevented.

And, if the front wheel differential mechanism is locked, the propulsive force of the left and right front wheels will not decrease, so the aircraft will not go straight and it is not necessary to steer the front wheels unnecessarily to correct the orientation of the aircraft. .

(Iv) In the preceding paragraph (iii), it may be possible to manually lock the front wheel differential mechanism, but such a manual lock operation may be delayed during turning.

In the paddy, if the front wheels on the outside stop and the front wheels on the inside spin at high speed and the propulsive force on the left and right front wheels decreases once, even if the front wheel differential mechanism is locked later,
It takes some time for the propulsive force of the left and right front wheels to return to the original state.

Therefore, if the front wheel differential mechanism is locked by the actuator in conjunction with the switching operation to the rear wheel deceleration state as in the present invention, the outer front wheels will stop without delaying the switching operation to the rear wheel deceleration state. The front wheel differential mechanism can be quickly locked before the inner front wheel spins at high speed.

[Effect of device]

As described above, in the four-wheel drive type rice transplanter, by driving the rear wheels to decelerate during turning, the slip phenomenon of the front wheels is reduced, while suppressing the effect on the seedlings due to the rough surface of the fields and the waves. You can now turn smoothly with good stability.

Then, by interlocking with the switching operation to the rear wheel deceleration state, the front wheel diff mechanism is quickly locked by the actuator, so that the inner front wheel idles and digs a groove in the rice field, or the aircraft goes straight without turning. Since such a situation is prevented in advance, it is possible to further suppress the roughening and rippling of the rice field at the time of turning.

〔Example〕

Hereinafter, a riding type rice transplanter according to an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 2, the engine frame is attached to the body frame (3) supported by a pair of left and right front wheels (1a), (1b) and rear wheels (2a), (2b).
The riding type rice transplanter is configured by mounting the (4) and the control section (5) and connecting the seedling planting device (7) so as to be able to move up and down through the four-link mechanism (6).

Next, the transmission system to the front wheels (1a), (1b) and the seedling planting device (7) will be described. As shown in FIG. 1, the power from the engine (4) is transmitted from the double tension clutch (8) to the input shaft (10) of the traveling transmission (9), and the power is transmitted to the first transmission shaft (11) and the first shaft (11). It is transmitted to the input gear (13a) of the front wheel differential mechanism (13) for the left and right front wheels (1a), (1b) via the two transmission shafts (12).
A shift member (14) is slidably fitted onto the second transmission shaft (12) by a spline structure so that the shift member (14) can be slid on the shift member (14).
By engaging the first gear (15) of the first transmission shaft (11) with the forward first speed state and by engaging the second gear (16) with the forward second speed state, the shift member (14) By engaging the reverse gear (18) of the third transmission shaft (17), the reverse state is obtained.

The power branched from the third transmission shaft (17) is transferred from the three-stage planting / planting inter-plant seedling transmission section (19) through the torque limiter (20), the planting clutch (21) and the PTO shaft (22). It is transmitted to the attachment device (7).

Next, the transmission system to the rear wheels (2a), (2b) will be described. As shown in Fig. 1, a small-diameter bevel gear (23) meshes with the input gear (13a) of the front wheel differential mechanism (13), and the power converted into high-speed and low-torque at this portion is transmitted by the fourth transmission. Axis (24),
It is transmitted to the front wheel differential mechanism (27) for the left and right rear wheels (2a), (2b) via the rear wheel transmission (25) and the fifth transmission shaft (26).

In the rear wheel transmission (25), as shown in FIG.
And the fifth transmission shaft (24), (26) are arranged to face each other, and the fourth transmission shaft
A shift member (28) is externally fitted to the (24) by a spline structure so as to be slidable. During normal straight travel, the spring (2
The shift member (28) is urged toward the occlusal side of the fifth transmission shaft (26) with the third gear (31) by the urging force of 9) through the oscillating shifter (30) to engage with each other. Cage, fourth and fifth transmission shaft (24),
(26) becomes a direct connection state, and front wheels (1a), (1b) and rear wheels (2a),
The standard drive state in which the drive speed in (2b) is approximately equal is in effect.
Then, the fourth gear (32) is fitted on the fourth transmission shaft (24) in an idle manner, and the shift member (28) is attached to the shifter (30) by the fourth gear (32).
A hydraulic cylinder (33) that is operated on the occlusal side with is provided.

On the other hand, as shown in Fig. 1, the left and right rear wheels (2a), (2b)
The side brakes (34a) and (34b) that independently brake the vehicle are provided, and the pedal operation is detected for the side brake pedals (35a) and (35b) linked to the side brakes (34a) and (34b). A pair of limit switches (36a) and (36b) are provided and connected to the control device (37).

A shift member (39) is slidably fitted to the transmission shaft (38) for one of the front wheels (1a) by a spline structure, and a hydraulic cylinder (42) (for sliding operation of the shift member (39) ( Equivalent to the actuator) is provided.

With the above configuration, when one planting process is completed and the aircraft reaches the edge, if one side brake pedal (35a) is depressed while steering the front wheels (1a), (1b), The control device (37) operates the control valve (40) for the hydraulic cylinder (33) to the pressure oil supply side. As a result, the shift member (28) is operated toward the fourth gear (32) side and engages with the fourth gear (32) side, so that the fourth transmission shaft (2
Power from 4) passes through 6th transmission shaft (41) to 5th transmission shaft (26)
Be transmitted to. This transmission state is a rear wheel deceleration state in which the driving speeds of the rear wheels (2a), (2b) are reduced more than the driving speeds of the front wheels (1a), (1b).

At the same time, the control device (37) controls the hydraulic cylinder (42).
Operate the control valve (43) for the pressure oil supply side. This causes the shift member (39) to move the input gear (13) of the front wheel differential mechanism (13).
The front wheel differential mechanism (13) is locked by engaging with a).

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the present invention is not limited to the structure of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 shows an embodiment of a four-wheel drive type riding rice transplanter according to the present invention, and FIG. 1 shows a traveling transmission, a rear wheel transmission, and a side brake pedal and a rear wheel transmission. A schematic plan view and FIG. 2 are overall side views of the riding-type rice transplanter. (1a), (1b) …… front wheel, (2a), (2b) …… rear wheel, (13) …… front wheel differential mechanism, (25) …… rear wheel transmission, (42) …… actuator.

Claims (1)

[Scope of utility model registration request] 1. A standard driving state in which the driving speeds of the front wheels (1a), (1b) and the rear wheels (2a), (2b) are substantially equal, and the driving speeds of the rear wheels (2a), (2b) are set to the front wheels (1a). ), (1b) is equipped with a rear wheel transmission (25) that can be switched to a rear wheel deceleration state in which the vehicle is decelerated from the drive speed, and the rear wheel transmission (25) can be switched to the rear wheel deceleration side. A four-wheel drive type riding rice transplanter equipped with an actuator (42) which interlocks and locks the front wheel differential mechanism (13) of the front wheels (1a), (1b).