JPH0591951U - Front wheel speed-up mechanism of tractor - Google Patents

Abstract

(57) [Summary] [Purpose] In a front wheel speed increasing device for a tractor configured to be able to switch between front wheel speed increasing state and front and rear wheel constant speed state, when traveling during work, when the engine speed is high at high speed Be able to safely turn the front and rear wheels at a constant speed. [Structure] The gear shift stage is detected by the sensor S1, the accelerator lever 6 position is detected by the sensor S2, and the steering angle is detected by the sensor S3. The transmission enters the high speed stage, the engine speed is high, and the steering angle is set. If the angle is more than
The front and rear wheels are configured to be in a constant speed state.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mechanism for controlling switching between a front wheel speed increasing state and a front and rear wheel constant speed state in a front wheel speed increasing device of a tractor.

[0002]

[Prior Art]

 Conventionally, when the tractor turns, the front wheel increases in comparison with the rotation speed of the rear wheel when the steering angle exceeds a certain level so that the field scene can be turned with a small radius without damaging the field scene. In addition, since the tractor may fall sideways when turning at a high speed, the front wheel speed increasing device of the tractor is known so that the front wheel speed increasing function works only when the transmission is in the low speed stage. -ing For example, it is a technique disclosed in Japanese Utility Model Publication No. 2-234449.

[0003]

[Problems to be solved by the device]

 In the above-mentioned conventional technique, the front wheel speed increasing mechanism switches to the front wheel speed increasing state only when the traveling angle is equal to or greater than the setting and the speed changing device is not set to the high speed state. The front wheel speed-up function does not work when in the gear, but when the engine is set to low speed, the running speed also decreases and it does not hinder turning with front wheel speed-up, so it is better to operate the accelerator than to shift gears. Returning to the low rotation side with the lever will make the operation easier and reduce noise, which is desirable for the operator. Therefore, if the front wheel speed increasing mechanism operates at high speed and the front wheel speed-increasing mechanism is activated, it will be dangerous to turn sharply.

[0004]

[Means for Solving the Problems]

 The present invention uses the following means in order to solve the above problems. That is, in the front wheel speed increasing device of the tractor configured to be able to switch between the front wheel speed increasing state and the front and rear wheel constant speed state, the gear position is detected by the sensor S1, the accelerator lever position is detected by the sensor S2, and the steering angle is detected by the sensor S3. When the transmission enters the high speed stage, the engine speed is high and the steering angle is equal to or greater than the set angle, the front and rear wheels are set to the constant speed state.

[0005]

[Action]

 With this configuration, when the steering handle 3 is at or above the set rotation speed and the accelerator lever 6 is on the high rotation side when the high speed stage is entered due to the signal from the sensor S1, the front wheel speed is increased. If the engine is running at a low speed, the front wheels will be accelerated and the turning radius will be small even at high speeds.

[0006]

【Example】

 The problems and configurations to be solved by the present invention are as described above. Next, embodiments of the present invention shown in the accompanying drawings will be described. FIG. 1 is an overall side view of a tractor using the present invention, and FIG. 2 is a control block diagram.

As shown in FIG. 1, the tractor has front wheels FW and rear wheels RW, and a working machine mounting device 1 for mounting various working machines is arranged at the rear part. A steering handlebar 3 is provided in front of the driver's seat 2, a main gearshift lever 4 and an auxiliary gearshift lever 5 are arranged on the side of the driver's seat 2, and below the front part of the driver's seat 2, Equipped with a clutch pedal 7, a brake pedal, and an accelerator pedal, the accelerator lever 6 attached to the lower portion of the steering handle 3 is used to operate the accelerator during work in the field. The number is changed.

The driving force of the engine E in the tractor is changed in the mission case 8 by operating the main speed change lever 4 and the auxiliary speed change lever 5 to drive the rear wheels RW, and protrudes forward from the mission case 8. The front wheel accelerating device 10 for switching between front wheel accelerating and front and rear wheel accelerating is transmitted via the transmission shaft 9 so that the front wheel FW can be accelerated or the front and rear wheels can be driven at a constant velocity via the front wheel differential 11. .

In order to control the front wheel speed-increasing device 10, a sensor S1 for detecting a speed changing position is provided at the rotation base of the auxiliary transmission lever 5, and a rotation amount is provided at the rotation base of the accelerator lever 6. A sensor S2 for detecting and a sensor S3 for detecting a turning angle are arranged at the turning base of the steering handle 3, and the front wheel speed increasing device 10 and the sensors S1, S2, S3 are connected to the controller 14. . However, the detection sensor S2 may detect the rotation speed of the engine instead of detecting the rotation amount of the accelerator lever 6 or may be arranged on a wire or the like in the middle. When the high and low speed shifts are performed in the first speed and the second speed, it is possible to provide a sensor on the main shift lever 4 and control the front wheel speed increasing device 10 based on the signals of both levers.

In such a structure, when the gear shift stage is detected by the sensor S1 during work and the steering handle 3 has a steering angle of a certain angle or more at a high speed stage, a sharp turn occurs. A signal from the steering angle detection sensor S3 is input by the controller 14, the front wheel speed increasing device 10 is not activated and the front and rear wheels are in a constant speed state, and the position of the accelerator lever 3 is detected by the sensor S2 to detect a low speed. At the high speed stage on the side, the front wheel speed increasing device 10 can be operated to make the turning radius small and smoothly turn without damaging the field.

[0011]

[Effect of the device]

 The present invention has the following effects by being configured as described above. That is, when the transmission of the tractor is in the high speed stage, the front wheels and the rear wheels are always in a constant speed state regardless of the steering angle, the steering handle 3 is rotated more than the set rotation, and the accelerator lever is moved. If it was turned to the low speed side, the front wheels were switched to the speed-up state, and the vehicle could turn at a low speed to prevent the tractor from overturning when turning, thus enabling safe operation.

[Brief description of drawings]

FIG. 1 is a side view of a tractor using the present invention.

FIG. 2 is a control block diagram.

[Explanation of symbols]

 FW Front wheel RW Rear wheel S1 Gear shift operation position detection sensor S2 Accelerator position sensor S3 Steering angle detection sensor 3 Steering handle 5 Sub gearshift lever 6 Accelerator lever 10 Front wheel speed increasing device

Claims (1)

[Scope of utility model registration request] 1. A front wheel speed-increasing device for a tractor configured to be able to switch between a front wheel speed-increasing state and a front-rear wheel constant-speed mode, wherein a gear position is a sensor S1 and an accelerator lever position is a sensor S.
2. If the steering angle is detected by the sensor S3, the transmission enters the high speed stage, and the engine speed is high and the steering angle is equal to or greater than the set angle, the front and rear wheels are in a constant velocity state. The front wheel speed-up mechanism of the tractor, which is configured to