JP2934034B2 - Differential device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device used for a vehicle.

[0002]

2. Description of the Related Art JP-A-63-195449 discloses a "slip-restricted differential gear assembly". This is a differential device that performs differential limiting with an electromagnetic multi-plate clutch. This multi-plate clutch is arranged between the internal gear side and the sun gear side of the planetary gear type differential mechanism.

[0003]

However, in this arrangement of the multi-plate clutch, the torque generated by the friction clutch becomes the differential limiting force as it is. To obtain a large differential limiting force, increase the number of clutch plates or The size of the electromagnet needs to be increased, resulting in an increase in the size of the device.

Accordingly, an object of the present invention is to provide a differential device capable of obtaining a sufficient differential limiting force without increasing the size of the device.

[0005]

SUMMARY OF THE INVENTION A differential device according to the present invention comprises a differential mechanism and first and second differential members provided on the first and second differential members, respectively, having different numbers of teeth.
And a second gear and a third gear engaged with these gears, and a friction clutch for coupling a carrier supporting the third gear with the first or second differential member. And characterized in that:

[0006]

The differential torque of the differential mechanism is reduced to a low torque via the mysterious gear mechanism and is input to the friction clutch. Since the mysterious gear mechanism can obtain a very large gear ratio even if it is small,
The input torque to the clutch can be greatly reduced, so that a sufficiently large differential limiting force can be obtained while reducing the size and capacity of the friction clutch.

[0007]

An embodiment will be described with reference to FIGS.
FIG. 1 shows an apparatus of this embodiment, and FIG. 2 shows a power system of a vehicle using this embodiment. Hereinafter, the left and right directions are the left and right directions in this vehicle and FIG. 1, and the upper part of FIG. 1 corresponds to the front of this vehicle (the upper part of FIG. 2). Further, members and the like without reference numerals are not shown.

First, the configuration of this power system will be described with reference to FIG. This power system includes an engine 1, a transmission 3, a propeller shaft 5, a rear differential 7 (a differential device shown in FIG. 1 used for a rear wheel), rear axles 9 and 11, left and right rear wheels 13 and 15, left and right front wheels 17 and 19 and the like.

Next, the rear differential 7 will be described.

A differential case 21 (first differential member) is supported in a differential carrier 23 via a bearing.
As shown in FIG.
Are fixed, and the ring gear 25 is connected to the drive pinion gear 2.
7 is engaged. The drive pinion gear 27 is formed integrally with the rear end of the drive pinion shaft 29 connected to the propeller shaft 5 side. Thus, the rotation of the engine 1 drives the differential case 21 to rotate from the transmission 3 via the propeller shaft 5.

The left and right hubs 3 are provided inside the differential case 21.
The left hub 31 is spline-connected to the left rear axle 9, and the right hub 33 is spline-connected to the right rear axle 11.

A differential mechanism 35 of a planetary gear type is arranged inside the differential case 21. That is,
An outer pinion gear meshes with the internal gear 37, an inner pinion gear 39 meshes with the outer pinion gear, and the pinion gear 39 meshes with a sun gear 41. The outer pinion gear is rotatably supported on an outer pinion shaft, and this pinion shaft is supported at both ends by left and right pinion carriers 43 and 45 (second differential members). The inner pinion gear 39 is rotatably supported on an inner pinion shaft 47, and both ends of the pinion shaft 47 are supported by the carriers 43 and 45, respectively. Washers 48, 48 are arranged between each pinion gear and the carriers 43, 45.

The internal gear 37 is formed on the differential case 21, and the sun gear 41 is formed on the left hub 31. The left and right pinion carriers 43, 45 are integrally welded. The right carrier 45 is integral with the right hub 33. An oil hole 51 is provided in a left side wall 49 of the differential case 21, and a washer 53 is disposed between the side wall 49 and the left carrier 43. Lubricating oil is sealed in the differential carrier 23, and the lubricating oil flows in from the oil hole 51 with the rotation of the differential case 21 to lubricate the inside of the differential case 21.

Thus, the differential mechanism 35 is constituted, and the rotation of the differential case 21 (internal gear 37) is divided into the sun gear 41 (hub 31) and the carriers 43, 45 (hub 33) via each pinion gear. , Hub 3
The power is transmitted to the right and left rear wheels 13 and 15 via the first and third wheels 33, and is differentially distributed to the left and right sides by the rotation and revolution of each pinion gear according to the driving resistance difference between the rear wheels.

On the right side of the differential mechanism 35, the pinion carrier 45 and the differential case 21
5, 57 (first and second gears) are formed respectively. A pinion gear 59 (third gear) meshes with these gears 55 and 57. The gears 55, 57 have slightly different numbers of teeth.

The pinion gear 59 includes a pinion shaft 61
The pinion shaft 61 is rotatably supported on the upper side, and both ends of the pinion shaft 61 are supported by left and right pinion carriers 63 and 65 (carriers). Pinion gear 59 and each carrier 63,6
Washers 67, 67 are arranged between the carrier 5 and the carrier 5, and the carriers 63, 65 are integrally welded. The cylindrical portion 69 of the right carrier 65 is rotatably supported on the hub 33.

Thus, the mysterious gear mechanism 71 is constituted, and the differential case 21 (gear 57) and the carrier 45
When the differential rotation between the gear 55 and the
The pinion gear 59 revolves while rotating on the top 57, and the carriers 63 and 65 rotate. This rotation is performed by gears 55 and 57.
The speed is increased to about six times the differential rotation of the motor and the torque is reduced to about 1/6.

A multi-plate clutch 73 for connecting the differential case 21 having a low torque end and the cylindrical portion 69 to each other is provided.
(Friction clutch). Multi-plate clutch 73
The armature 75 is arranged on the left side of the
The contact with the carrier 65 is prevented by the retaining ring 77 on the side.

A ring-shaped electromagnet 79 is arranged on the right side of the differential case 21, and is supported on the cylindrical portion 83 of the differential case 21 by bearings 81, 81. The yoke 85 of the electromagnet 79 is provided with bolt holes 87 for fixing the electromagnet 79 to the differential carrier 23.

The right side wall 89 of the differential case 21 has an electromagnet 7
A non-magnetic ring 91 is embedded to prevent short-circuit of the magnetic force of No. 9 and guide it to the armature 75.

When the electromagnet 79 attracts the armature 75, the multi-plate clutch 73 is pressed and fastened between the right side wall 89 and the carriers 63, 65 with a strength corresponding to the fastening force.
(Pinion gear 59) is connected to the differential case 21 side and is rotationally braked. With this braking force, the differential rotation between the gear 55 (pinion carrier 45) and the gear 57 (diff case 21) is braked, and the differential of the differential mechanism 35 is limited.

Since the coupling force of the multi-plate clutch 73 is amplified six times by the mysterious gear mechanism 71 as described above, a sufficiently large differential limiting force can be obtained even if the multi-plate clutch 73 and the electromagnet 79 are miniaturized. Can be

When the engaging force (slip) of the multi-plate clutch 73 is adjusted by the electromagnet 79, the differential limiting force of the differential mechanism 35 can be controlled. When the fastening force is sufficiently increased, the differential mechanism 35 is locked and the differential between the rear wheels 13 and 15 is stopped. When the fastening force is moderately reduced, the differential between the rear wheels is allowed. When released, this differential is free.

The control of the differential limitation by the electromagnet 79 can be manually operated from the driver's seat, or can be automatically operated according to road surface conditions, vehicle steering conditions, and the like.

Thus, the rear differential 7 is formed.

In the vehicle shown in FIG.
Even if one of the wheels 3 and 15 slips, the running performance is maintained by the driving force sent to the other rear wheel via the rear differential 7 by the differential limiting force. If the differential limiting force of the rear differential 7 is increased, the straight running stability of the vehicle is improved by limiting the differential between the rear wheels, and if the differential limiting force is reduced, the differential between the rear wheels is allowed and smooth turning is possible. I can do it.

According to the mysterious gear mechanism, about 1/30
The torque can be reduced to a certain extent, and the friction clutch and its fastening means can be reduced in size accordingly.

[0028]

The differential device according to the present invention is configured such that the differential torque of the differential mechanism is reduced to a low torque via the mysterious gear mechanism and is input to the friction clutch. Since the mysterious gear mechanism can obtain a high gear ratio even with a small size, a sufficient differential limiting force can be obtained while reducing the size of the friction clutch.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment.

FIG. 2 is a skeleton mechanism diagram showing a power system of a vehicle using the embodiment.

[Explanation of symbols]

 21 differential case (first differential member) 35 differential mechanism 43, 45 pinion carrier (second differential member) 55, 57 internal gear (first and second gears) 59 pinion gear (third gear) 63, 65 Pinion carrier (carrier) 71 Wonder gear mechanism 73 Multi-plate clutch (friction clutch)

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16H 1/445 B60K 17 / 20,17 / 348

Claims (1)

(57) [Claims] 1. A differential mechanism and first and second differential mechanisms.
A mysterious gear mechanism having first and second gears, each having a different number of teeth, and a third gear meshing with these gears, respectively, are provided on the differential member side, and the third gear is supported. A differential device comprising: a friction clutch for connecting a carrier to the first or second differential member.