JPH0448350Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field] This invention relates to a differential device.

[Prior Art] In general, differential devices for vehicles, etc., ensure smooth running by absorbing the rotational difference, that is, the differential, that occurs between the drive shafts of the wheels when the vehicle changes direction or turns. ing. However, if a vehicle slips on a muddy road surface with a small road friction coefficient, for example, if one of the left or right wheels slips, the driving force is not transmitted to the other wheel due to the structure, making it impossible to escape from the muddy surface.

For this reason, some vehicles are equipped with a differential limiting mechanism to limit the differential rotation and escape from the mud when one wheel slips and a differential occurs between the left and right wheels.

As a differential device provided with such a differential limiting mechanism, for example, the one described in Japanese Patent Publication No. 57-4536 is known. The main structure is to rotatably support the left and right output sides of the differential case containing pinion gears, side gears, etc. on the fixed differential carrier, and to provide a friction plate between the boss of one side gear and the inner peripheral surface of the differential case. A pressure plate for pressing the friction plate is provided on the differential case boss portion, and the friction plate is clamped and integrated by pressing the pressure plate with a cylinder. By adjusting the degree of engagement of the friction plates, that is, the frictional force, the differential limiting load can be adjusted to enable locking, unlocking, etc.

[Problems to be solved by the invention] By the way, in such a structure, when the wheel on the side gear side where the friction plate is not provided slips, a corresponding torque is applied to the friction plate side due to the fastening force of the friction plate. The information is transmitted to the side gear on the same side, allowing for a smooth escape using the wheels on the same side. On the other hand, when the wheel on the opposite side slips, torque is transmitted from the side gear on the same side to the side gear on the opposite side via the pinion gear due to the fastening force of the friction plate, allowing a smooth escape.

However, in the former case, in which torque is transmitted to the side gear on the side where the friction plate is provided, torque is transmitted according to the fastening force of the friction plate, but in the latter case, in which torque is transmitted to the side gear on the opposite side. Thrust force is generated by the meshing between the side gear and pinion gear, and frictional force is generated between the opposite side gear and the differential case, so torque corresponding to this frictional force is added from the differential case to the same side gear, and the torque is applied to the left and right sides. There was a problem that the differential limiting torque transmission characteristics of the two types would be different.

Therefore, this invention has been devised in view of the above-mentioned problems, and provides a differential device that can make the differential limiting torque characteristics substantially equal on the left and right sides.

[Means for solving the problem] This invention has the following configuration in order to solve the above problem.

That is, the differential device according to this invention includes a differential case capable of receiving rotational input, a pinion shaft supported by the differential case, a pinion gear rotatably supported by the pinion shaft, and a gear meshing with the pinion gear. A differential device comprising a pair of side gears, a differential limiting means provided between one of the side gears and the differential case to limit the differential movement between the two, and an actuating means for switching on and off the operation of the differential limiting means. The side gear on the side where the differential limiting means is provided is configured to interlock with the axle side member via a cam on a surface facing the rotating shaft direction, and the side gear on the side gear on the side where the differential limiting means is provided is interlocked with the axle side member via a cam on a surface facing the rotational axis direction, and the side gear is connected to the differential case side by the action of the cam on the axle side member. The structure is such that a friction surface to be fastened is provided.

(Function) According to the above configuration, when the wheel on the side gear side where the friction plate is not provided slips, the fastening force of the friction plate and the action of the cam are applied between the opposing surfaces of the wheel side member and the differential case in the rotational axis direction. Due to the fastening force, a corresponding torque is transmitted to the side gear on the friction plate side, and the wheel on the same side can smoothly escape. On the other hand, when the wheel on the opposite side slips, torque is transmitted from the side gear on the same side to the side gear on the opposite side via the pinion gear due to the fastening force of the friction plate, and the fastening force of the friction plate and the fastening force between the side gear and the differential case are This also allows for a smooth escape.

[Example] Hereinafter, an example of this invention will be described in detail based on the drawings.

In FIG. 1, 1 generally indicates a differential device disposed, for example, between the left and right axles on the rear wheel side, 3 a differential control means, 5 a pressure member, and 7
indicates a driving means, and the pressure member 5 and the driving means 7 constitute an actuating means for turning on and off the operation of the differential limiting means 3.

A ring gear 11 is integrally attached to the differential case 9 of the differential device 1, and the ring gear 11 is rotated by a drive pinion gear 13 (partially not shown) to which rotational driving force from an internal combustion engine is transmitted. Inside the differential case 9, side gears 15 and 17 arranged on the left and right sides are rotatably supported, and the side gears 15 and 17 mesh with each other via a pinion gear 21 rotatably supported on a pinion shaft 19 supported on the differential case 9. However, the rotation is transmitted to left and right axles 23 and 25 (partially not shown) that are engaged with the side gears 15 and 17. However, the side gear 15 is a member 75 on the axle side.
are interlocked via a cam mechanism 71. Details will be described later. In addition, the differential case 9
is rotatably supported by a differential carrier 29 via bearings 27 provided on the left and right sides.

As the differential limiting means 3, a multi-plate friction latch 31 is incorporated between the differential case 9 and one of the side gears 15 to limit differential differential by using frictional force. This multi-plate friction clutch 31 includes a plurality of first friction plates 3 that are engaged in the circumferential direction with spline grooves 33 provided on the inner peripheral surface of the differential case 9 and are movable in the axial direction.
5 and this first friction plate 35 are alternately combined,
It is comprised of a plurality of second friction plates 39 that engage in the circumferential direction with a spline groove 37 provided on the outer peripheral surface of the side gear 15 and are movable in the axial direction.

These friction plates 35 and 39 are pressed and moved so that they come into contact with each other and the friction clutch 31 is fastened.
In other words, the pressure member 5 is provided as a member that presses and moves in the direction of increasing frictional force.

This pressure member 5 is a pressure ring 4
1 is fitted onto the outer circumferential surface of the differential case 9 on the side gear 17 side so as to be movable in the axial direction of the axle 25. The pressure ring 41 and the friction clutch 31 are connected by a pressure rod 45 that is slidably inserted into a plurality of holes 43 formed in the differential case 9 along the axial direction of the axle 25.

On the other hand, in the drive means 7, an annular hydraulic cylinder 47 is interposed between the differential carrier 29 and the pressure ring 41. The rear end protrusion 51 of the cylinder portion 49 of the hydraulic cylinder 47 is fitted and fixed into the bearing fitting hole 53 of the differential carrier 29. In addition, the hydraulic cylinder 4
A ring-shaped piston 55 facing the pressure ring 41 is fitted into the cylinder portion 49 of No. 7 through a sealing member (such as an O-ring) 57 so as to slide in a liquid-tight manner.

On the other hand, a thrust bearing 59 is interposed between the front end surface of the piston 55 and the abutting surface of the pressure ring 41, and the retainer on the inner peripheral side of the thrust bearing 59 engages with the rear step portion 61 of the pressure ring 41. It has been stopped. The hydraulic oil chamber 63 of the hydraulic cylinder 47 is connected to the outside through a hydraulic oil supply hole provided on one side of a differential carrier cover 67 for maintenance, which is attached to the lower side of the differential carrier 29 in the figure, through a hydraulic oil pipe 65. It's communicating.

When the piston 55 slides due to the pressure of this hydraulic oil and presses the pressure ring 41 and pushes the friction clutch 31 in the direction of increasing friction, the side gear 15
The relative rotation between the side gears 15 and 17 is restricted and differential control is performed.
A cam mechanism 71 is provided between one side gear 15 and the differential case 9 so that the differential limiting torque is equally applied to the left and right axles 23 and 25.

This cam mechanism 71 is shown in detail in FIG.
A cam 73a having an annular trapezoidal shape and facing the rotating shaft direction is provided on the side surface (left side in FIG. 1) of the side gear 15, and a cam 73b that meshes with the cam 73a is formed on the axle side member 75. The member 75 is provided with a friction surface 75a that is fastened to the differential case side via a thrust washer 77 by the action of the cam mechanism 71. The pressure angle of the cams 73a, 73b means that the thrust force generated by the cams 73a, 73b is applied to the pinion gear 21 and the side gears 15, 1.
It is configured to be equal to the thrust force generated by the meshing of No.7. Also, the other side gear 1
7 also has a thrust washer 7 between it and the differential case 9.
7 is interposed.

With the above configuration, the operation is such that when one of the left and right wheels, for example, the side gear 17 side where the differential limiting means 3 is not provided, slips in the mud and a differential occurs while the vehicle is running, this difference occurs. The movement is limited by differential limiting means 3. That is, hydraulic oil is supplied to the hydraulic oil supply hole 6 by a control system (not shown) consisting of a sensor, a control circuit, a regulator, etc., or by a manual.
9 is supplied to the hydraulic oil chamber 63 via a pipe 65.

The piston 55 presses the pressure ring 41 by the pressure of the hydraulic oil supplied to the hydraulic oil chamber 63, and presses the friction clutch 31 in the direction of increasing friction (leftward in FIG. 1) via the pressure rod 45. . When the friction clutch 31 is pressed, the relative rotation between the side gear 15 and the differential case 9 is restricted as the pressing force increases, and torque is transmitted to the side gear 15.

At this time, the torque transmitted to the side gear 15 is the fastening force between the first friction plate 35 and the second friction plate 39, and the fastening force via the thrust washer 77 on the friction surface 75a between the axle side member 75 and the differential case 9. It is adapted to the following. Cam mechanism 71
This action is based on the fact that the member 75 on the axle side with respect to the side gear 15 receives ground resistance during torque transmission.

On the other hand, when the wheel on the side gear 15 side slips, torque corresponding to the fastening force of the differential limiting means 3 is transmitted to the pinion gear 21 and the side gear 17, and the torque is transmitted to the pinion gear 21 and the side gear 17.
Side gear 1 is activated by the thrust force generated by meshing gears 5 and 17.
7 connects to the differential case 9 via the thrust washer 77
The torque is transmitted accordingly.
The torque transmission by this thrust force is substantially the same as the torque transmission by the action of the cam mechanism 71, and the differential limiting torque characteristics are substantially equal on the left and right sides. Therefore, it is possible to improve the steering stability.

[Effects of the invention] As is clear from the above explanation, according to the configuration of this invention, the characteristics of the differential limiting torque can be improved by interposing a cam in the side gear on the side where the differential limiting means is provided. The left and right sides can be made approximately equal, improving steering stability.

[Brief explanation of the drawing]

1 and 2 show a differential device according to an embodiment of this invention, with FIG. 1 being a sectional view and FIG. 2 being an enlarged sectional view taken along the line - in FIG. 1. Explanation of symbols indicating main parts of the drawings: 1...Differential device, 3...Differential limiting means, 5...Press member, 7...Driving means, 9...Differential case, 15...Side gear, 17... ...side gear,
19... Pinion shaft, 21... Pinion gear, 73a, 73b... Cam, 75... Axle side member, 75a... Friction surface.

Claims (1)

[Scope of utility model registration request] A differential case that can receive rotation input,
A pinion shaft supported by the differential case, a pinion gear rotatably supported by the pinion shaft, a pair of side gears meshing with the pinion gear, and a pair of side gears provided between one side gear and the differential case to control differential movement between the two. A differential device comprising a differential limiting means for limiting the differential, and a differential means for switching on and off the operation of the differential limiting means, the differential limiting means is arranged so that the side gear on the side where the differential limiting means is provided is connected to the member on the axle side. What is claimed is: 1. A differential differential device that is interlocked with each other via a cam on an opposing surface in the direction of a rotating shaft, and is provided with a friction surface that is fastened to a differential case side by the action of the cam on a member on the axle side.