JPS5812832A - Slip prevention device for driving wheel - Google Patents

Abstract

PURPOSE:To suppress slips and prevent wheels from devastating a field or being sunk by reducing the number of revolutions of driving wheels automatically when a certain amount of slips occurs. CONSTITUTION:Detection results by a revolution speed detection unit 1 for front wheels and a revolution speed detection unit 2 for rear wheels are fed into a comparator 5 through arithmetic units 3, 4 respectively. The comparator 5 is a unit to determine the magnitude of slips by comparing the revolutions of front and rear wheels, and the obtained results are fed into a decision unit 6, which is a unit to decide whether to operate a deceleration unit 7 or not based on the magnitude of slips obtained by the comparator 5, thus the decision unit 6 operates the deceleration unit 7 when the magnitude of slips has reached a preset value or above and stops the operation of the deceleration unit 7 when the amount of slips has been reduced below the preset value.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slip prevention device that effectively prevents the drive wheels of a two-wheel drive tractor from slipping.

The condition of the farmland where the tractor is used varies greatly from place to place, so if you try to drive at a constant speed, the drive wheels may slip and unduly roughen the ground, or the wheels may sink, making it impossible to escape. It often happened. Although such slips can be prevented by reducing the rotation speed of the drive wheels, it is extremely cumbersome and impractical for the operator to change the rotation speed in small increments in response to changes in soil conditions.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a sagging prevention device that can effectively reduce the rotational speed of a drive wheel depending on the occurrence of slip. This will be explained below.

The drive wheel sagging prevention device according to the present invention includes a rotation speed detection device that detects the rotation speed of both front and rear wheels in a two-wheel drive tractor, and a comparison that compares the rotation speeds of the front and rear wheels detected by the rotation speed detection device. A device and a speed reduction device linked to the comparison device are provided, and when a certain amount of shear occurs on the drive wheel side, the speed reduction device is activated to reduce the rotational speed of the drive wheels. It is said that below,
Embodiments will be specifically described with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an example of the drive wheel sagging prevention device according to the present invention, and shows the detection results of the front wheel rotation speed detection device 1 and the rear wheel rotation speed detection device 2. The signals are input to a comparator 5 via arithmetic units 3 and 4, respectively. The calculation units 3 and 4 are provided as necessary, and perform calculations such as multiplying and matching coefficients for compensating for the difference in diameter between the front wheels and the rear wheels. The comparison device 5 is a device that compares the rotational speeds of both the front and rear wheels to determine the amount of shear, and the obtained results are supplied to the determination device 6. The determination device 6 is a device that determines whether or not to operate the deceleration device 7 based on the size of the scoop obtained by the comparison device 5,
When the size of the slip exceeds a preset value, the deceleration device 7 is activated, and when the slip becomes less than the preset value, the deceleration device 7 is stopped.

The rotation speed detection device 2 is, for example, an axle.

A device is provided in which a projection serving as a reference point is provided on the axle in the housing and a photosensor is attached to the axle, and the number of times the projection passes in front of the photosensor is counted to detect the rotational speed of the axle. Can be used. A magnet may be used as a reference point, and this may be detected by a magnetic sensor.

FIG. 2 is a cross-sectional view of the main parts of the driving force transmission device.
An intermediate shaft 9 is connected through the intermediate shaft 9, and a drive pinion shaft 1o is connected to the rear end of the intermediate shaft 9. In the illustrated example, a planetary gear type transmission is used as the reduction gear 7, and an internal gear 71 is provided at the rear end of the main transmission shaft 8. A planetary gear 74 that is rotatably supported by a pin 73 on a pair of left and right carriers 72 provided at the tip of the intermediate shaft 9 meshes with this internal gear 71 . Further, a hollow shaft 11 having a sun gear 75 that meshes with the planetary gear 74 is provided on the outer circumference of the intermediate shaft 9, and is rotatably supported by bearings 12 and 12'. The hollow shaft 11 is provided with an outer cylindrical portion 11' projecting from its outer periphery, and a hydraulic operating device 13 for switching the quick-tooth heavy transmission described in L is provided in this portion. The front half of the hydraulic operating device 13 is an oil 11-clutch section 13a, and the rear half is a brake section 1:3b. The urashi 1 set operating device 13 is operated by the operating surface supplied from the operating valve (see the figure) via the oil feed pipe 14, 15 (7).
If the actuating surface is supplied through the piston, the piston moves forward (to the left in the figure) to the outer cylinder 11' side.
I! The friction plate 17 and the friction plate 18 on the carrier 72 side are joined, and the outer cylindrical portion 11' and the carrier 72 are combined.As a result, the intermediate shaft 9 is directly connected to the main transmission shaft 8. It will now rotate as one body. In addition, when the operating surface is supplied through the oil pipe 15, the piston 19 moves backward to join the friction plate 20 on the outer cylinder portion 11' side and the static friction plate 22 fixed on the end cover 21 side. Therefore, the sun gear 75 remains stationary, and the rotation of the main transmission shaft 8 meshes with the internal gear 71 and rotates.
A is decelerated by A and transmitted to the intermediate shaft 9, which is integrated with the carrier 72. The reduction ratio in this case is determined by the number of teeth of the internal gear 71 and the number of teeth of the sun gear 75, and usually a reduction ratio of about 25% is adopted. If a planetary gear type transmission equipped with such a hydraulic operation device 13 is adopted as the reduction gear device 7, the reduction device can be easily operated by simply switching the hydraulic operation valve using a solenoid or the like. It is convenient because it becomes

The drive wheel slip prevention device according to the present invention is configured as described above, and when the soil condition changes during work and a certain amount of slippage occurs on the drive wheel, the device automatically controls the rotation speed of the drive wheel. Since the pressure is lowered to suppress shearing, it is possible to effectively prevent accidents such as unnecessarily damaging the field or causing the wheels to sink and make it difficult to escape. It became.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a slip prevention device according to the present invention, and FIG. 2 is a sectional view of a main part of a power transmission section. All figures show examples. 1.2... Rotation speed detection device, 5... Comparison device, 6.
... Judgment device, 7... Reduction device, 8... Main transmission shaft, 9
...Intermediate shaft, 11...Hollow shaft, 11'...Outer cylinder part, 13...Hydraulic operating device, 71...Internal tooth gear, 7
2.Carry 4., 74...Planetary gear, 75...Sun gear. Patent applicant: Iseki Agricultural Machinery Co., Ltd. Agent: Patent attorney: Hiroshi Sugawara Figure 1

Claims (2)

[Claims] (1) In a two-wheel drive tractor, a rotation speed detection device for detecting the rotation speed of both front and rear wheels; a comparison device for comparing the rotation speeds of the first and front wheels detected by the rotation speed detection device;
and a speed reduction device linked to the comparison device, and when a certain amount of sagging occurs on the drive wheel side, the speed reduction device is activated to reduce the rotational speed of the drive wheels. Drive wheel sagging prevention device. (2) The driving wheel sagging prevention device according to claim 1, which uses a planetary southeast type transmission as a speed reduction device interlocked with the comparison device.