JPH048671A - Wheel gear of tractor - Google Patents

Abstract

PURPOSE:To turn a tractor with safety by providing a transfer clutch, a normal gear and a reversing gear between a differential axle by means of which a driving force is transmitted from a differential gear to both right and left wheels and a wheel axle. CONSTITUTION:While a tractor makes turns, the claw clutch 27 side of a turning side transfer clutch 8 is off and the friction clutch 26 side of the clutch 8 is on. The clutch 26 is gradually let in and switches to transmission on the side of a reversing gear 12 or 13: when e.g. a left turning side rear wheel 2 is rotated reversely, a sudden turn of the tractor is achieved by the reverse rotation and also by the normal rotation of an outside rear wheel 3. But the reverse rotation by the gear 12 is transmitted at remarkably reduced speed as an absolute value compared to the transmission ratio of a normal gear 11 opposite to the gear 12 and so reverse transmission can be set to slow speed. Since transmission by the gear 12 is permitted when a differential gear locking device 28 is locked, the left rear wheel 2 is rotated in the reverse direction and the right rear wheel 3 opposite to the wheel 2 are rotated in the normal direction with accuracy whereby the tractor can make a smooth turn.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a wheel transmission device for a tractor.

When turning, the inside wheels are driven in the reverse direction to allow the vehicle to turn quickly.

(Prior art and problem to be solved by the invention) When turning when turning around at the edge of a field or at the end of a working line, it is necessary to disengage the steering clutch on the turning side, apply the brake, or The vehicle is rotated in the opposite direction to make a turn in accordance with the driving conditions, but when the vehicle is turned in the reverse direction, the inner wheel is rotated slowly to ensure a safe turn. be.

(Means for Solving the Problems) The present invention provides differential axles 4 and 5 for transmitting power from a differential device 1 to left and right axles 2.3, and a wheel axle 6 having the axles 2 and 3.
, 7, there are switching clutches 8, 9 for switching the axle 2.3 on the left and right turning side between normal rotation and reverse rotation, and a forward rotation gear 10.11 and a reverse rotation gear 12.13 that transmit transmission to the axle by this switching.
The structure of an axle transmission device for a tractor is provided with:

(Function) Travel transmission is performed by switching the switching clutches 8 and 9 from the differential device 1 to the differential axle 4.5, and when the switching clutches 8 and 9 are in the normal forward rotation side, the forward and reverse gears 10.11 are Then, the wheel axles 6 and 7 are rotated, and the axle 2.degree. 3 is rotated in the normal direction. Further, when the switching clutches 8 and 9 are switched to the reverse rotation side, the wheels 2.3 are reversely rotated through the reverse rotation gear 12.13.

In this traveling transmission, when performing a turning steering operation, for example, when turning to the left, the left switching clutch 8 is moved from the forward gear 10 to the reverse gear 12 by operating the steering wheel by a predetermined angle to the left. was switched to
Reverse transmission is transmitted to the wheels 2 from this left differential axle 4 via a reverse gear 12, a wheel shaft 6, etc.

(Effect of the invention) In this way, between the differential axles 4, 5 and the wheel axles 6, 7, the forward/reverse gears 10, 11 and the reverse gears 12, 13, which switch the rotational transmission direction by the switching clutches 8, 9, are provided. By setting these gear ratios, it is possible to reduce the transmission rotation during reverse turning, and the turning can be performed at a safe speed.

(Example) When turning, the left and right front axles 14 are moved from the pitman arm 17 of the power steering 16 to the rotor 18 at the front of the vehicle body by operating the steering handle 15.
The knuckle arms 19 of each front axle 14 are steered in conjunction with each other via the front axle. A rear axle housing 21 protrudes to the left and right sides on the rear side of a mission case 20 housing a transmission that transmits power from the engine, and a final case part 22 having a vertical height difference is formed on both left and right sides. There is.

The left and right rear axles 2 and 3 are mounted on the lower part of the final case 22 by wheel axles 6 and 7.

A differential device 1 rotated by a drive shaft 23 in a mission case 20 is located in the center of the rear axle housing 21, and differential axles 5 and 6 are mounted on both left and right sides of the differential device 1. The final case 22 is provided with a switching clutch 8.9, forward rotation gears 10, 11, reverse rotation gears 12.13, and the like.

The switching clutches 8, 9 in each differential axle 4, 5 consist of a friction plate clutch 26 and a pawl clutch 27 operated by a controller having a microcomputer CPU via a hydraulic system 24, 25, and transmit the reverse gear 12, 13 side. The friction plate clutch 26 is used to operate the forward rotation gear 10.11.
A claw clutch 27 is used to transmit power on the side. The meshing gear ratio of the reverse rotation gears 12 and 13 is made smaller than the meshing gear ratio of the forward rotation gear 10.11 interlocking between each differential axle 4.5 and the wheel axles 6 and 7, thereby transmitting deceleration. .

26.27 is an intermediate gear of the reverse gear 12.13.

The differential gear 1 has a differential lock l [2
8 is provided, and the differential lock or unlock operation can be performed by operating the differential lock petal 29. Also, a differential lock sensor 30 detects the differential lock of the differential lock device 28, an auxiliary shift sensor 32 detects a deceleration position suitable for cornering by the auxiliary shift lever 31, and a steering direction and a shift of the front axle 14 by the pitman arm 17. Steering sensors 33, 34 for detecting angles are provided, and each of these sensors 30, 32, 33 . or 34, the hydraulic device 24 or 25 causes the claw clutch 27 on the normal rotation gears 10, 11 to be in the engaged state, and the friction clutch 26 in the switching clutch 8 or 9 to be engaged. 6. That is, a switching clutch 8. or 9
is switched to the reverse gear 12 or 13 on the turning side only when the differential is locked during a turning stroke with a large steering angle.

During normal forward running, the differential gear 1 moves the left and right differential axles 4
, 5, claw clutch 27 of switching clutches 8 and 9, forward rotation gear 10.11. and the left and right rear axles 2 via the wheel axles 6, 7, etc.
, 3 is transmitted. The differential locking of the differential gear 1 is performed by operating the differential locking pedal 29.

During a turn, when the pitman arm 17 reaches a turning angle of a certain angle or more due to the operation of the steering handle 15, this turning angle is detected by the turning angle sensors 33 and 34. At this time, the sub-shift sensor 32 detects the deceleration position and the differential lock pedal is activated. 29 is detected, and the pawl clutch 27 side of the switching clutch 8 or 9 on the turning side is disengaged and the friction clutch 26 side is engaged. This friction clutch 2
6 is gradually turned on and the transmission is switched to the reverse gear 12 or 13 side. In this way, for example, when the rear wheel 2 on the left turning side is rotated in the reverse direction, the outer rear wheel 3 is rotated in the normal direction, resulting in a sharp turn. However, since the reverse rotation by the reverse rotation gear 12 is transmitted at a significantly reduced absolute value with respect to the transmission ratio of the forward rotation gear 11 on the opposite side, the reverse rotation transmission can be set to a slow speed. Furthermore, since the transmission by the reverse gear 12 is performed when the differential lock device 28 is locked, the reverse rotation of the left rear wheel 2 and the forward rotation of the right rear axle 3 on the opposite side can be accurately controlled. You can move around and make smooth turns.

In Fig. 3, the difference from the upper part is that in conjunction with the brake operation of the left and right brake pedals 35 and 36, the brakes 37 or 38 that brake the rotation of the differential axles 4 and 5 on both the left and right sides are braked. When activated, the switching clutch 8 or 9 is controlled to be switched to the reverse direction.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is a plan view showing the transmission mechanism, Fig. 2 is a partial control block diagram, and Fig. 3 is a plan view showing the transmission mechanism.
The figure is a plan view of a transmission mechanism showing a partially different embodiment. (Explanation of symbols) 1 Differential device 2, 3 Wheels 4.5 Differential axle 6, 7 Wheel axle 8.9 Switching clutch 10.11 Forward gear 1.2.13 Reverse gear

Claims (1)

[Claims] The wheels 2 and 3 on the left and right turning side are rotated in the normal direction between the differential axles 4 and 5 that transmit power from the differential device 1 to the wheels 2 and 3 on both the left and right sides, and the wheel axles 6 and 7 that have the wheels 2 and 3. , switching clutches 8 and 9 that switch to reverse rotation, and forward rotation gears 10 and 11 and reverse rotation gears 12 and 13 that transmit wheel transmission by the switching.