JPH05162560A - Control device for differential limiting device - Google Patents

Abstract

PURPOSE:To attain the stable high-speed travel of a vehicle by automatically locking a differential device at the time of a high-speed travel with a relatively simple structure. CONSTITUTION:A sleeve is spline-fitted slidably in the axial direction at one of the drive shafts of a rear axle 14, the sleeve is formed demountably with one side differential case, and a driving means 37 moves the sleeve in the axial direction of one drive shaft. A steering sensor 47 detects the steering angle of a steering wheel 46, and a vehicle speed sensor 48 detects the vehicle speed. When the vehicle speed sensor 48 detects the vehicle speed at a preset value or above and the steering sensor 47 detects the steering angle of the steering wheel 46 below a preset value, a controller 49 hooks the sleeve on one side differential case via the driving means 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a device for locking a differential between right and left driving wheels of a vehicle.

[0002]

2. Description of the Related Art Conventionally, as a left and right drive wheel differential limiting device, a sleeve that engages and disengages with one differential case has been spline-fitted to one drive shaft, and this sleeve has been connected to an air tank via a switching valve. There is known a structure in which a switching valve is switched by being driven by an air cylinder and operated by a manual switch provided in a driver's cab. When the vehicle is located on a road surface in which the left and right drive wheels are muddy, snowy or frozen, that is, a low friction road is started, when the manual switch is turned on, one of the differential cases is passed through the switching valve and the air cylinder. Since the sleeve is locked to lock the differential between the left and right drive wheels, the drive wheels do not slip. Also, if the switch is turned off after exiting the low friction road, the differential mechanism functions for the left and right drive wheels when the vehicle travels on a normal curved road.

However, in the above device, in order to improve the running stability during high speed running, the driver must operate the manual switch each time during high speed running to lock the sleeve in the differential case, which is troublesome to operate. There was a problem.

In order to solve this point, the engine power input from the drive pinion is distributed to the left and right drive wheels via a differential mechanism to generate a differential resistance force between the drive pinion and the drive wheels. A differential limiting device is provided in which a differential limiting mechanism is provided, and a controller controls the differential limiting mechanism based on a detection output of an acceleration state detection sensor that detects an acceleration state of a vehicle (Japanese Patent Laid-Open No. 59-102321). ).
The differential limiting mechanism of this device has a multi-plate clutch, and the multi-plate clutch is pressed against each other by hydraulic drive means, and the controller controls the hydraulic drive means to adjust the differential resistance force according to the acceleration state of the vehicle. It is like this.

[0005]

However, the above-mentioned device for changing the differential resistance force according to the acceleration state of the vehicle has a drawback that the mechanism is complicated and the number of parts and assembling steps are increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a differential limiting device which enables a stable high speed running of a vehicle by automatically locking the differential device during high speed running with a relatively simple mechanism. ..

[0007]

A configuration of the present invention for achieving the above object will be described with reference to FIGS. 1 and 2 corresponding to the embodiments. The present invention includes a pair of side gears 28 and 29 spline-fitted to the left and right drive shafts 31 and 32, diff pinions 33 and 33 meshed with the side gears and fitted into the spider 34, side gears 28 and 29, and diff pinions 33 and 33. And rotatably housing the differential case 26, 2
7 and one of the drive shafts 31, 32 is spline-fitted and slid in the axial direction of the drive shaft 32 so that the differential case 26,
A sleeve 36 that can be engaged with and disengaged from one of the two 27, and a drive means 37 that moves the sleeve in the axial direction of the one drive shaft 32.
It is an improvement of the differential limiting device having and. The characteristic configuration is that the steering sensor 47 that detects the steering angle of the steering wheel 46 and the vehicle speed sensor 4 that detects the vehicle speed.
8 and a controller 49 for controlling the drive means 37 based on the detection outputs of the steering sensor 47 and the vehicle speed sensor 48.

[0008]

Operation: The vehicle speed sensor 48 detects a vehicle speed above a predetermined value,
When the steering sensor 47 detects a steering angle of the steering wheel 46 that is less than a predetermined value, the controller 4
Reference numeral 9 locks the sleeve 36 to the one differential case 27 via the driving means 37. When the vehicle speed sensor 48 detects a vehicle speed lower than a predetermined value, the steering sensor 47 detects a steering angle of the steering wheel 46 which is a predetermined value or more, or both sensors 47 and 48 simultaneously detect the above state, the controller 49 Removes the sleeve 36 from the one differential case 27 via the drive means 37.

[0009]

An embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the engine 11 of the vehicle 10
The rotational force generated by the left and right rear wheels 16, 1 is transmitted through the transmission 12, the propeller shaft 13, and the rear axle 14.
7 is transmitted. As shown in FIGS. 2 and 3, the drive pinion 18 of the rear axle 14 is inserted into the housing 19 and is rotatably supported via the bearings 21 and 22 and the cage 23. Ring gear 2 for drive pinion 18
4 meshes, and the ring gear is fixed to one of the differential cases 26, 27. A pair of left and right side gears 28 and 29 are provided in the differential cases 26 and 27, respectively.
Is spline-fitted to one end of the drive shaft 31, and the other ends of the drive shafts 31 and 32 are connected to the left and right rear wheels 16 and 17, respectively (FIG. 1). Further, four diff pinions 33, 33 (of which two diff pinions are not shown) mesh with the side gears 28, 29 in the diff cases 26, 27. These diff pinions 33, 33 are spiders 34 formed in a cross shape.
The respective spiders are rotatably fitted in the respective arms and the spiders are fixed to the differential cases 26 and 27. Differential case 26, 2
7, the side gears 28 and 29, the diff pinions 33 and 33, and the spider 34 constitute a differential mechanism. Clutch teeth 27a are integrally formed on one of the differential cases 27, and a sleeve 36 is spline-fitted to one drive shaft 32 to the right of the clutch teeth so as to be slidable in the axial direction. The sleeve 36 is formed with a sleeve tooth 36a that can be engaged with and disengaged from the clutch tooth 27a.

The sleeve 36 is moved in the axial direction of the drive shaft 32 by the drive means 37, and the drive means 37 is moved by the air cylinder 3.
8 and a switching valve 39 and an air tank 41. The air cylinder 38 is attached to an axle housing 42, one end of a shift fork 43 is fixed to a piston rod 38a of the air cylinder 38, and the other end of the shift fork is locked to the outer peripheral surface of the sleeve 36. Piston rod 38
The piston 38b attached to the right end of a is a cylinder 38
It is provided in c and this piston is a compression coil spring 38d.
Is urged in the direction of the solid arrow in FIG. Switching valve 39
Is a spring return type three-way switching solenoid valve in this example, and the port 39a of the switching valve 39 is connected to the cylinder 38c. The port 39b of the switching valve 39 is connected to the air tank 41, and the port 39c is connected to the atmosphere. When the switching valve 39 is turned on, the ports 39a and 39c are communicated with each other to discharge the compressed air in the cylinder 38c to the atmosphere, and when the switching valve 39 is turned off, the ports 39b and 3 are connected.
The compressed air in the air tank 41 is supplied into the cylinder 38c by communicating with the cylinder 9a (FIG. 1).

The steering column 44 is provided with a steering sensor 47 for detecting a steering angle of a steering shaft, that is, a steering wheel 46.
Is a vehicle speed sensor 4 for detecting the rotation speed of the spindle, that is, the vehicle speed.
8 are provided. Each detection output of the steering sensor 47 and the vehicle speed sensor 48 is connected to the control input of the controller 49, and the control output of the controller 49 is connected to the switching valve 39 (FIG. 1). A predetermined value to be compared with the detection value of the steering sensor 47, 90 degrees in this example, and a predetermined value to be compared with the detection value of the vehicle speed sensor 48, 60 km / h in this example, are stored in the memory of the controller 49. Further, a manual switch (not shown) is provided in the driver's cab. When the manual switch is turned on regardless of the detection outputs of the steering sensor 47 and the vehicle speed sensor 48, the switching valve 39 is switched to lock the sleeve teeth 36a to the clutch teeth 27a. It is like this.

The operation of the control device for the differential limiting device thus configured will be described. The vehicle speed sensor 48 detects a vehicle speed of 60 km / h or more, and the steering sensor 47 detects 90
When the steering angle of the steering wheel 46 of less than 100 degrees is detected, the controller 49 switches the switching valve 39 so that the port 39a and the port 39c are in communication with each other. Cylinder 38
The compressed air in c is discharged to the atmosphere, and the compression coil spring 38
The elastic force of d causes the piston 38b and the piston rod 3 to
8a moves as shown in FIG. 2 and the sleeve teeth 36a are locked to the clutch teeth 27a. As a result, the differential between the left and right rear wheels 16 and 17 is locked, and the stability of the vehicle 10 during high speed traveling is improved. In addition, the vehicle speed sensor 48 is 60
When the vehicle speed less than km / h is detected, the steering sensor 47 detects the steering angle of the steering wheel 46 of 90 degrees or more, or both the sensors 47 and 48 simultaneously detect the above state, the controller 49 causes the switching valve 39 to operate. Is switched so that the ports 39b and 39a communicate with each other.
The compressed air in the air tank 41 is supplied into the cylinder 38c, the piston 38b and the piston rod 38a move as shown in FIG. 3 against the elastic force of the compression coil spring 38d, and the sleeve teeth 36a separate from the clutch teeth 27a. .. As a result, the differential mechanism causes the left and right rear wheels 16,1
7, the vehicle 10 can smoothly run on a curved road. Further, the vehicle 10 located on the low friction road
When a manual switch (not shown) is turned on when the vehicle starts, the sleeve teeth 36a are locked to the clutch teeth 27a via the switching valve 39 and the air cylinder 38 to lock the differential between the left and right rear wheels 16 and 17. , Rear wheels 16,1
The vehicle 10 can start smoothly without slipping of the vehicle 7.

Although the vehicle speed reference value of 60 km / h and the steering angle reference value of the steering sensor of 90 degrees are stored in the memory in the embodiment, the present invention is not limited to these values. Further, although the air cylinder, the solenoid valve and the air tank are used as the driving means in the embodiment, this is an example and a linear solenoid or other driving means may be used.

[0014]

As described above, according to the present invention, the sleeve is spline-fitted to one of the drive shafts so as to be slidable in the axial direction and is detachably attached to the differential case, and the drive means is the sleeve. Is moved in the axial direction of one of the drive shafts, the steering sensor detects the steering angle of the steering wheel, the vehicle speed sensor detects the vehicle speed, and the controller controls the drive means based on the detection outputs of the steering sensor and the vehicle speed sensor. As a result, the left and right differentials are automatically locked during high speed travel, and the stability of the vehicle during high speed travel can be improved. Further, since the mechanism is simpler than the differential limiting device using the multi-plate clutch, the cost is not increased significantly.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a truck including a control device for a differential limiting device according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a portion A of FIG. 1 showing a state in which sleeve teeth are engaged with clutch teeth.

FIG. 3 is a cross-sectional view corresponding to FIG. 2, showing a state in which the sleeve teeth are disengaged from the clutch teeth.

[Explanation of symbols]

 10 Vehicle 26, 27 Differential Case 28, 29 Side Gear 31, 32 Drive Shaft 33 Differential Pinion 34 Spider 36 Sleeve 37 Drive Means 46 Steering Wheel 47 Steering Sensor 48 Vehicle Speed Sensor 49 Controller

Claims (1)

[Claims] 1. A pair of side gears (28,29) spline-fitted to the left and right drive shafts (31,32), and a differential pinion (33,33) engaged with the side gears and fitted in a spider (34).
And the side gears (28,29) and the differential pinion (33,33)
And a diff case (26, 27) that rotatably accommodates, and the diff case (26) that is spline-fitted to one (32) of the drive shafts (31, 32) and slides in the axial direction of the drive shaft (32). 26, 27) a sleeve (36) that can be engaged with and disengaged from one (27), and drive means (37) for moving the sleeve in the axial direction of the one drive shaft (32).
In a limited slip differential device having a steering wheel (46) for detecting a steering angle of a steering wheel (46), a vehicle speed sensor (48) for detecting a vehicle speed, the steering sensor (47) and a vehicle speed sensor (48). ), And a controller (49) for controlling the drive means (37) based on each detection output of (1).