JPH05164199A - Differential limiting device - Google Patents

Abstract

PURPOSE:To realize a stable high speed travel of a vehicle by increasing differential limiting torque at the time of high speed travel by means of a simple mechanism. CONSTITUTION:In the case of a pressurization type differentiation limit device, a clutch chamber 28a is provided among a side gear 21, a differential case 18 and a clutch case 28, and spline fitting is made to the side gear 21, and friction disks 33 are provided at the clutch chamber 28a, and spline insertion is made into the clutch case 28, and friction plates 34 are provided at the chamber 28a. Disks 33 and plates 34 are mutually joined by means of a bellevile spring 36, and a ringlike pressure member 37 is provided at the clutch chamber 28a. One side surface of the pressure member 37 butts against a disk 33 or a plate 34, and plural recessed grooves 37a is radially formed on the other side surface of the pressure member 37. The bottom portion of a recessed groove 37a is formed so that the thickness of the pressure member 37 may become larger from the inner periphery toward the outer periphery, and ball bodies 38 that are movable in the radial direction of the pressure member 37, are respectively fitted to recessed grooves 37a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for limiting the differential between the left and right drive wheels of a vehicle. More specifically, the present invention relates to a preload type differential limiting device capable of increasing the differential limiting torque during high speed traveling.

[0002]

2. Description of the Related Art In this type of preload type differential limiting device, a clutch chamber is formed between one side gear, a differential case and a clutch case, and a plurality of friction discs provided in the clutch chamber are spline fitted to the side gear. Then, the plurality of friction plates inserted between the discs in the clutch chamber are spline-inserted into the differential case. The disc and the plate are pressed against each other by the elastic force of the disc spring. This device uses a disc spring to join the disc and the plate by the elastic force of a disc spring when a vehicle 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. The differential between the left and right drive wheels is limited to prevent the wheels from slipping. The differential limiting torque of the above device cannot be made too strong so that the differential operates on the left and right drive wheels when the vehicle travels on a normal curved road.

On the other hand, when the vehicle travels at a high speed on a straight road, it is desired to rotate the left and right drive wheels at the same speed with a high differential limiting torque for stable travel. Therefore, a device is known in which the actuator is operated in response to the vehicle speed to adjust the differential limiting torque.

[0004]

However, the conventional device for changing the differential limiting torque in response to the vehicle speed has a problem that the mechanism is complicated and the number of parts and assembling steps are increased.

An object of the present invention is to provide a differential limiting device which has a simple mechanism and which increases the differential limiting torque during high-speed traveling to enable stable high-speed traveling of a vehicle.

[0006]

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 is directed to a pair of side gears 21 and 22 spline-fitted to the left and right drive shafts 23 and 24 of the vehicle located in the differential cases 18 and 19, one of the side gears 21, one of the differential cases 18, and the rear surface of the differential case 18. Clutch chamber 28a provided between the clutch chamber 28 and the bowl-shaped clutch case 28 fixed to the clutch chamber 28, a friction disc 33 provided in the clutch chamber and spline fitted to one side gear 21, and a clutch case provided in the clutch chamber 28a. It is an improvement of the differential limiting device including a friction plate 34 spline-inserted in 28 and a joining means 36 for joining the disk 33 and the plate 34 to each other. The characteristic configuration is that the clutch chamber 28a is provided with a pressure member 37 formed in a ring shape, one side surface of the pressure member 37 abuts on the plate 34, and the other side surface of the pressure member 37 has a plurality of concave grooves 37a. Are formed radially, the bottom of the concave groove 37a is formed such that the thickness of the pressure member 37 increases from the inner circumference to the outer circumference, and a spherical body 38 movable in the radial direction of the pressure member 37 is formed in the concave groove 37a. They are in the places where they are installed.
Further, the plate 34 may be spline-inserted into the differential case 18 instead of the clutch case 28. Further, one side surface of the pressure member 37 may abut the disk 33 instead of the plate 34.

[0007]

When the vehicle travels at a high speed, the centrifugal force acting on the sphere 38 increases, and the sphere 38 causes the concave groove 3 of the pressure member 37 to move.
By moving from the inner circumference to the outer circumference of 7a, the spherical body 38 increases the joining force between the friction disk 33 and the friction plate 34 via the pressure member 37.

[0008]

An embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 and 2, the drive pinion 11 is inserted into the carrier case 12, and the bearing 13,
It is rotatably supported via 14 and the cage 16. A ring gear 17 meshes with the drive pinion 11, and the ring gear 17 is fixed to the differential cases 18 and 19. A pair of left and right side gears 21, 2 are provided in the differential cases 18, 19.
2 are spline-fitted to one ends of the drive shafts 23 and 24, respectively, and the other ends of the drive shafts 23 and 24 are connected to the left and right rear wheels, respectively. Further, in the differential cases 18 and 19, four differential pinions 26 and 26 (two differential pinions are not shown) mesh with the side gears 21 and 22. These diff pinions 26, 26 are rotatably fitted into respective arms of a spider 27 formed in a cross shape, and the spider 27 is fixed to the diff cases 18, 19. A clutch case 28, which will be described later, fixed to the differential case 19 and the differential case 18 is provided with a carrier case 1 via bearings 31 and 29.
2 is rotatably supported.

A boss 21a is formed integrally with the side gear 21, and a clutch chamber 28a is formed by the boss 21a, the rear surface of the differential case 18, and a bowl-shaped clutch case 28 fixed to the rear surface of the differential case 18. A plurality of disc-shaped friction discs 33 are spline-fitted to the boss 21a in the clutch chamber 28a so as to be slidable in the axial direction of the drive shaft 23. Also, the clutch chamber 28a
The plurality of disc-shaped friction plates 3
4 is inserted between the disks 33, and is splined in the clutch case 28 so as to be slidable in the axial direction of the drive shaft 23. The joining means 36 for joining the disc 33 and the plate 34 to each other is, in this example, two disc springs arranged on the right side surface of the plate at the right end, and depending on the elastic force of the disc spring 36, the disc 33 and the plate 34 are joined together. Are joined together.

The characteristic structure of this embodiment is that one side surface of the pressure member 37 formed in a ring shape abuts the plate 34 at the left end, and a plurality of radial concave portions formed on the other side surface of the pressure member 37. The spheres 38 are mounted in the grooves 37a so as to be movable in the radial direction of the pressure member 37. The bottom of the groove 37a is formed so that the thickness of the pressure member 37 increases from the inner circumference toward the outer circumference.
That is, the cross section is formed in a wedge shape, and the spherical body 38 has the concave groove 37a.
And a ring-shaped recess 28 formed in the clutch case 28
It is held in a state of being sandwiched between b.

The operation of the differential limiting device thus configured will be described. When the vehicle gradually shifts from low-speed traveling to high-speed traveling, the rotational speeds of the clutch case 28 and the pressure member 37 increase, and the spherical body 3 rotating with them increases.
The rotation speed of 8 also increases. At this time, the sphere 38 shown in FIG.
The centrifugal force acting in the direction indicated by the solid arrow increases, and the spherical body 38 moves from the inner circumference to the outer circumference of the concave groove 37a of the pressure member 37. As a result, the force (indicated by the one-dot chain line arrow) perpendicular to the bottom surface of the concave groove 37a acting on the pressure member 37 increases, and the component of this force parallel to the drive shaft 23 (indicated by the broken line arrow) increases. Therefore, this component force is added to the joint force of the disc spring 36 between the friction disc 33 and the friction plate 34, the differential limiting torque is increased, and the stability of the vehicle at high speed is improved. When the vehicle starts on a low friction road, the disc 33 and the plate 34 are joined by the elastic force of the disc spring 36.
The differential between the left and right drive wheels is limited, and the drive wheels can start without slipping.

Although the disc spring is used as the joining means in the embodiment, this is merely an example, and a compression coil spring or another spring member may be used. Further, in the embodiment, a plurality of friction discs and a plurality of friction plates inserted between these discs are mentioned, but the present invention is not limited to this, and a single friction disc and a single friction plate may be used.

[0013]

As described above, according to the present invention, the clutch chamber is provided between one of the side gears, one of the differential cases, and the bowl-shaped clutch case fixed to the rear surface of the differential case. The friction disc is spline-fitted into the clutch chamber, the spline is inserted into the clutch case, the friction plate is provided in the clutch chamber, and the disc and the plate are joined together by the joining means to form a ring-shaped clutch chamber. A pressure member is provided, one side surface of the pressure member contacts the disk or the plate, a plurality of concave grooves are radially formed on the other side surface of the pressure member, and the bottom portion of the concave groove is directed from the inner circumference to the outer circumference. Of the pressure member is mounted in the groove so that it can be moved in the radial direction. Because, without slippage between the friction disk and the friction plate differential limiting torque is increased at the time of high speed running is generated, thereby enabling stable high speed running. Further, since the mechanism is simple as described above, the number of parts and the number of assembling steps can be slightly increased, and the cost hardly increases.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of a portion A of FIG. 2 of a differential limiting device according to an embodiment of the present invention.

FIG. 2 is a sectional view of a rear axle including the device.

[Explanation of symbols]

 18, 19 Differential case 21, 22 Side gear 23, 24 Drive shaft 28 Clutch case 28a Clutch chamber 33 Friction disc 34 Friction plate 36 Disc spring (joining means) 37 Pressure member 37a Recessed groove 38 Sphere

Claims (1)

[Claims] 1. A pair of side gears (21, 22) spline-fitted to left and right drive shafts (23, 24) of a vehicle located in a differential case (18, 19), and one of the side gears (21) A clutch chamber (28a) provided between one of the differential case (18) and a bowl-shaped clutch case (28) fixed to the back surface of the differential case (18), and one of the one provided in the clutch chamber. A friction disc (33) spline-fitted to the side gear (21), a friction plate (34) provided in the clutch chamber (28a) and spline-inserted into the clutch case (28) or the differential case (18), and disk
Joining means for joining the (33) and the plate (34) to each other
(36) in the differential limiting device, wherein the clutch chamber (28a) is provided with a ring-shaped pressure member (37), one side surface of the pressure member (37) is the plate (3).
4) or the disk (33), and a plurality of grooves (37) on the other side surface of the pressure member (37).
a) is formed radially, the bottom of the groove (37a) is formed such that the thickness of the pressure member (37) increases from the inner circumference to the outer circumference, and the pressure groove is formed in the groove (37a). A differential limiting device characterized in that a spherical body (38) movable in a radial direction of a member (37) is attached to each member.