JPH0517485Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a differential device with a differential limiting mechanism.

(Prior Art) When a vehicle changes its direction of travel or makes a turn, a differential device applies differential motion to the left and right wheels to ensure smooth running. However, if one of the left and right wheels slips while the vehicle is on a muddy road surface with a low coefficient of road friction, the driving force is not transmitted to the other wheel due to its structure, making it impossible to escape from the mud. For this reason, when one wheel slips in mud and a differential is created between the left and right wheels, some differential gears are equipped with a differential limiting mechanism that limits this differential and allows you to escape from the mud. .

An example of a differential device equipped with such a differential limiting mechanism is the one shown in FIG. 5.

In Fig. 5, 1 is a differential case of a differential device, and a ring gear (not shown) is attached to this differential case 1, and the rotational driving force from the internal combustion engine is transmitted to this ring gear. A drive pinion gear (not shown) is engaged. Further, a fitting groove 2 is formed in the differential case 1, and a protruding end portion of a pinion shaft 3 is fitted into this fitting groove 2. A pinion gear 4 is rotatably attached to the pinion shaft 3, and a pair of side gears 5 and 6 mesh with the pinion gear 4. A viscous coupling ring 7 is disposed between the differential case 1 and the side gears 6 as a differential limiting mechanism that limits relative rotation thereof.

This viscous cut spring 7 is the differential case 1
It has a viscous coupling chamber 9 defined by a side gear 6, a side wall member 8 interposed between the differential case 1 and the side gear 6.
The viscous coupling chamber 9 accommodates a rotary plate 10a that is spline-fitted to the differential case 1, and a rotary plate 10b that is spline-fitted to the side gear 6, and is also filled with viscous fluid. Seal members 11 and 12 are interposed between the side wall member 8, the differential case 1, and the side gear 6, respectively.

By the way, the relative rotational speed of the side wall member 8 and the side gear 6 when the differential case 1 and the side wall member 8 are rotated integrally is
The relative rotation speed of the side wall member 8 and the differential case 1 is slower than that when the side wall member 8 and the differential case 1 are rotated together. That is,
The seal member 12 interposed between the side gear 6 and the side wall member 8 is more secure than the differential case 1 and the side wall member 8.
The sealing member 11 interposed between the sealing member 11 and the sealing member 11 does not wear out. Therefore, in order to improve the durability of the seal members 11 and 12, it is better to rotate the differential case 1 and the side wall member 8 together. Therefore, the side wall member 8
is press-fitted into the differential case 1, and the locking pin 13 is fitted into the fitting groove 2 and the side wall member 8,
The side wall member 8 is configured to rotate together with the differential case 1.

(Problems to be Solved by the Invention) However, in such a differential device with a differential limiting mechanism, the side wall member 8 is fixed so that the differential case 1 and the side wall member 8 rotate together.
Since the entire outer circumferential surface of the side wall member 8 is press-fitted into the differential case 1, the side wall member 8 is strained due to the pressing force of the entire outer circumferential surface.
There is also a risk that it may become deformed. Therefore, if the side wall member 8 is deformed, the clearance or interference between the seal 12 and the side gear 6 may become inaccurate, or the side wall member 8 and the side gear 6 may slide in close contact with each other. Also, insert the locking pin 13 into the fitting groove 2.
However, since the contact area of this detent pin 13 with the differential case 1 is small, the reliability of integral rotation of the differential case 1 and the side wall member 8 is low, and if something happens, the side wall member 8 may There is a risk that it will wobble relative to the differential case 1.

As a result, due to the sliding contact between the side wall member 8 and the side gear 6, and due to the wobbling of the side wall member 8, the durability of this differential device with a differential limiting mechanism may decrease, and the sealing performance may deteriorate. There was a problem that the quality was inferior.

(Means for Solving the Problems) In order to solve these problems, this invention includes a differential case that receives rotational driving force,
A side gear that meshes with a pinion gear rotatably attached to the differential case via a pinion shaft, and a side wall that is interposed between the side gear and the differential case and defines a differential limiting mechanism chamber filled with viscous fluid. a seal member provided between the side wall member and the differential case and between the side wall member and the side gear to seal the differential limiting mechanism chamber, and a sealing member provided within the differential limiting mechanism chamber and integrated with the differential case. A differential limiting mechanism with a differential limiting mechanism includes a plurality of rotating rotary plates and a differential limiting mechanism in which a plurality of rotating plates rotating integrally with the side gear are alternately arranged, wherein the differential case and the differential limiting mechanism are provided with The side wall member is interposed between the side gear and the side gear through a gap, and the seal member is interposed in the gap, and the side wall member is formed with a fitting portion that fits with the differential case, and the shaft of the side wall member It is characterized by providing an axial movement restriction means for restricting movement in the direction.

(Function) Since the side wall member is connected to the differential case by fitting, and the axial movement restricting means is provided,
The portion where the side wall member presses the differential case is small. Therefore, it is possible to prevent the differential case or the side wall member from being strained and deformed due to the press-fitting of the side wall member. Furthermore, since the side wall member is fitted into the differential case, the area of the fitting portion between the side wall member and the differential case is increased, and the reliability of integral rotation of the side wall member and the differential case is improved. Furthermore, since the axial movement of the side wall member with respect to the differential case is restricted, play does not occur between the side wall member and the differential case during integral rotation.

(Example) This invention will be explained below based on the drawings. 1 to 3 are diagrams showing an embodiment of a differential device with a differential limiting mechanism according to this invention.

First, the configuration will be explained.

1 and 2, 21 is a differential case of a differential device, and a ring gear (not shown) is attached to this differential case 21, and this ring gear receives rotational driving force from an internal combustion engine. is rotated by a drive pinion gear (not shown) transmitted thereto. The differential case 21 houses a side gear 23 that is spline-fitted to a drive shaft 22 that rotationally drives one of the left and right wheels, and a fitting groove 24 is formed in the inner wall of the differential case 21 in parallel with the axial direction of the drive shaft 22. They are formed at four equal intervals around this axis. A protruding end of a pinion shaft 25 having a substantially cross shape is fitted into the fitting groove 24 . A pinion gear 26 is rotatably attached to the pinion shaft 25, and this pinion gear 26 meshes with the side gear 23, and also meshes with a side gear 28 that is spline-fitted to a drive shaft 27 that rotationally drives the other of the left and right wheels. are doing. A substantially annular side wall member 30 is fitted between the differential case 21 and the side gear 28. Also,
A viscous coupling spring 29 is disposed between the differential case 21 and the side gears 28 as a differential limiting mechanism that limits their relative rotation.

The viscous coupling spring 29 has an operating chamber 31 defined by the differential case 21, the side gear 28, and a side wall member 30 interposed between the differential case 21 and the side gear 28. The operating chamber 31 has a rotary plate 3 that is spline-fitted with a spline 32 carved on the inner circumferential surface of the differential case 21.
3 and a plurality of rotary plates 35 that are spline-fitted with splines 34 carved on the outer circumferential surface of the side gear 28 are alternately housed. As shown in FIG. 3, the spline 3 carved in the differential case 21
The tooth tip of the end 32a (the right end of the spline 32 in FIG. 1) on the side wall member side of No. 2 is formed to protrude radially inward from the spline 32 other than this end 32a. That is, the height of the teeth of the spline at the end 32a is higher (has a smaller diameter) than the height of the teeth of the spline 32 other than this end 32a.

The side wall member 30 has a differential chamber 31 on its outer peripheral surface.
A spline 36 as a fitting portion is formed on the side portion to protrude from the outer circumferential surface, and this spline 3
6 is the end 32 of the spline 32 of the differential case 21
This end portion 32a is spline-fitted with
The bottom of the spline 36 is press-fitted and fixed to the tooth tip of the spline 36. Therefore, the side wall member 30 rotates integrally with the differential case 21 rather than with the side gear 28.

The viscous coupling spring chamber 31 is filled with silicone oil as a viscous fluid. It is sealed.

Next, the effect will be explained.

Since the spline 36 is formed on the outer peripheral surface of the side wall member 30 on the side of the viscous coupling chamber 31, the side wall member 30 can be spline-fitted and press-fitted into the end 32a of the spline 32 of the differential case 21. It rotates integrally with the differential case 21. Therefore, in order to rotate the side wall member 30 integrally with the differential case 21, it is no longer necessary to press fit the entire outer circumferential surface of the side wall member 30 into the differential case 21, and the outer circumferential surface of the side wall member 30 other than the splines 36 has a gap with respect to the differential case 21. It can be used as a reference. Therefore, it is possible to prevent the side wall member 30 from being distorted and even deformed due to the pressing force of the entire outer circumferential surface of the side wall member 30. Therefore, when the side wall member 30 and the side gear 28 are in close contact with each other, Sliding is inhibited. Also, the gap in the seal part,
The sealing becomes accurate and the sealing performance can be improved.

Here, in this invention as well, the side wall member 30 is press-fitted into the differential case 21.
The spline 36, which is a part of the entire outer peripheral surface of the side wall member 30, is simply press-fitted into the spline 2a. Therefore, simply pressing the differential case 21 with a portion of the entire outer circumferential surface of the side wall member 30 does not result in strain occurring in the side wall member 30.

Furthermore, since the side wall member 30 and the differential case 21 are spline-fitted, the area of the fitting area between the side wall member 30 and the differential case 21 is larger compared to the conventional case in which a detent pin is fitted into the differential case. The reliability of integral rotation with 21 is improved. Therefore, the side wall member 30 does not wobble with respect to the differential case 21, thereby suppressing a decrease in the durability of the seal member and improving the durability of this differential device with a differential limiting mechanism.

On the other hand, in order to rotate the side wall member 30 integrally without press-fitting the side wall member 30 into the differential case 21, a method can be considered in which the splines 32 of the differential case 21 and the splines 36 of the side wall member 30 are simply fitted without being press-fitted. However, in this method, play is provided between the tooth surfaces of the spline 32 and the tooth surface of the spline 36 in order to achieve spline fitting. Therefore, due to this play, play occurs between the side wall member 30 and the differential case 21 when the side wall member 36 and the differential case 21 are rotated together. Therefore, due to this backlash, the side wall member 30 moves in the axial direction, and the seal member 37 interposed between the side wall member 30 and the differential case 21
There is a possibility that the durability of this differential device with a differential limiting mechanism may be reduced due to wear of the outer circumferential wall of the side wall member 30 and the inner circumferential wall of the differential case 21.

However, in this invention, the differential case 21
Since the spline 36 of the side wall member 30 is spline-fitted and press-fitted to the end portion 32a of the spline 32, the side wall member 30 does not move in the axial direction. Therefore, a seal member 37 interposed between the side wall member 30 and the differential case 21
The outer circumferential wall of the side wall member 30 and the inner circumferential wall of the differential case 21 will not be worn out.

In addition, when assembling this differential device with a differential limiting mechanism, when assembling the side wall member 30 by inserting it between the differential case 21 and the side gear 28, the spline 32 of the differential case 21
The spline 36 of the side wall member 30 is fitted from the left end side, the side wall member 30 is moved to the right in FIG. 2, and the spline 36 is press-fitted into the end 32a of the spline 32. Spline 36 at end 32a
Since there is a gap between the tips of the splines 32 and the bottoms of the splines 36 until they are press-fitted, the side wall member 30 can be slid to the right and the assembly is easy.

Next, another embodiment of the differential device with a differential limiting mechanism according to this invention is shown in FIG. Incidentally, the same members as in the above embodiment are given the same reference numerals. In this embodiment, the tooth tips of the splines 32 are not made to protrude to form an end portion 32a, but the tooth tips of the splines 41 of the side wall member 30 are made to protrude toward the outer peripheral side in the radial direction. Therefore, the spline 32 and the spline 41 fit together, and the spline 41 is press-fitted into the spline 32. In this embodiment as well, the side wall member 30 and the differential case 21 can be rotated together without any play, as in the previous embodiment.

In the above embodiment, the splines of the side wall member and the splines of the differential case were fitted together, and the splines of the side wall member were press-fitted into the splines of the differential case. A convex portion may be formed on the outer circumferential surface of the side wall member or the inner circumferential surface of the differential case and press-fitted therein. Even in this case, the operation is substantially the same as in the above embodiment. FIG. 5 shows another embodiment in which a snap spring 50 is used as the axial regulating means, and FIG. 6 shows yet another embodiment in which a spring pin is used as the axial regulating means. 52 is shown. In Figures 5 and 6, since the integral rotation is performed at the spline part, sufficient strength can be obtained;
Effects similar to those shown in the embodiment can be obtained.

(Effects of the invention) As explained above, according to this invention, since the side wall member is connected to the differential case by fitting and the axial direction regulating means is provided, the side wall member is pressed radially inward by the differential case. This prevents the side wall member from deforming, and also prevents the side wall member from wobbling relative to the differential case, and from causing looseness between the side wall member and the differential case. do not have. Furthermore, there is no possibility that the sealing member interposed between the side wall member and the differential case will be worn out, and the side wall member and the differential case will not be worn out. Therefore, the durability of this differential device with a differential limiting mechanism can be improved.

[Brief explanation of drawings]

1 to 3 are diagrams showing a differential device with a differential limiting mechanism according to this invention, FIG. 1 is an overall perspective view of this differential device, and FIG. 2 is a diagram of this differential device. A sectional view of the allencial device, FIG. 3 is an enlarged sectional view of a portion of FIG. 2. 4 to 6 are views showing other embodiments of the differential device with a differential limiting mechanism according to this invention, and in detail are enlarged sectional views of the main parts thereof. FIG. 7 is a sectional view showing a conventional differential device with a differential limiting mechanism. 21...Differential case, 28...Side gear, 2
5... Pinion shaft, 26... Pinion gear, 30... Side wall member, 36, 41... Fitting portion,
32, 32a... Fitting portion.

Claims (1)

[Scope of utility model registration request] A differential case that receives rotational driving force, a side gear that meshes with a pinion gear that is rotatably attached to the differential case via a pinion shaft, and a differential that is interposed between the side gear and the differential case and has viscous fluid sealed in it. a side wall member defining a limiting mechanism chamber; a sealing member provided between the side wall member and the differential case and between the side wall member and the side gear to seal the differential limiting mechanism chamber; and the differential limiting mechanism. A differential limiting mechanism with a differential limiting mechanism, which is provided indoors and includes a plurality of rotating plates that rotate integrally with the differential case, and a differential limiting mechanism in which a plurality of rotating plates that rotate integrally with the side gear are arranged alternately. In the seal device, the side wall member is interposed between the differential case and the side gear via a gap, and the seal member is interposed between the differential case and the differential case is fitted to the side wall member. What is claimed is: 1. A differential device with a differential limiting mechanism, comprising: an axial movement regulating means for regulating axial movement of the side wall member;