JPH0736831Y2 - Anti-vibration support structure for differential gear - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a differential device mounted on a vehicle such as an automobile. More specifically, the present invention relates to an anti-vibration support structure for a differential device in which a differential carrier is attached to an axle tube by bolting.

(Prior Art) In vehicles such as automobiles, it has been generally known that vibrations and noises of a drive system are transmitted through a body part to the inside of the vehicle, which causes an abnormal noise in the vehicle to give a driver discomfort. Has been. In order to solve this problem, various measures are taken in the vibration transmission path of the drive system.
The most common and widely used measure is to interrupt vibration transmission by interposing an elastic body such as rubber in the transmission path.

For example, there is a method disclosed in Japanese Utility Model Publication No. 57-40761.
This publication discloses a structure in which an extension housing of a transmission and a shift lever retainer are fastened and fixed with bolts. Also, a configuration in which an elastic body is interposed between the both and the bolt is shown. The elastic body interposed near the bolt has a U-shaped cross section.

FIG. 5 shows an overall view of a conventional structure of a differential device targeted by the present invention. Differential carrier 1 and axle tube 2
Are rigidly connected by bolts 3. As well known, components such as a drive pinion and a differential case (not shown) are built in the differential carrier 1. In the case of this structure, since the differential carrier 1 and the axle tube 2 are rigidly coupled to each other, uneven rotation occurs due to a meshing error of the internal gears, which causes vibrations in the gears, and the vibrations cause the vibrations of the differential carrier 1 and the axle tube 2. Is transmitted to the body through each member and is radiated as an abnormal noise in the vehicle compartment. This abnormal sound is an unpleasant sound generally called differential gear noise. As a general means for solving this problem, it is conceivable to apply the vibration isolating structure between the extension housing of the transmission and the shift lever retainer to the differential device targeted by the present invention. FIG. 6 shows the configuration when applied. The axle tube 2 is rigidly connected to the bolt 3. An elastic body 4 having a U-shaped cross section is interposed between the differential carrier 1 and the bolt 3. Therefore, the diff carrier 1 and the axle tube 2 are not rigidly coupled but have an anti-vibration structure that is coupled by the elastic body 4.

(Problems to be Solved by the Invention) However, in the differential device to which the above-described known vibration damping structure is applied, the elastic body 4 has a U-shaped cross section having a corner portion 4a as shown in FIG. ing. Therefore, the arrow c, shown in FIG.
When a moment in the d direction acts, stress is applied to the elastic body 4 in the directions of arrows a and b shown in FIG. 6, and due to the biting action of the flange portion 1a of the differential carrier 1, etc.
There is a problem that stress concentration occurs in 4a, the elastic body is fatigued at an early stage, and durability is poor.

It is also possible to divide the above-mentioned stresses a and b in the two directions into elastic bodies so that the respective elastic bodies receive the stresses to avoid stress concentration, but this method increases the number of elastic body points, and It will take time to assemble.

Further, in the case of the differential device targeted by the present invention, unlike the case of the configuration of the connecting portion between the extension housing of the transmission and the shift lever retainer, which is different from the case of the above-mentioned configuration, the transmission path for transmitting the power from the engine to the drive wheels is provided. Since the device is arranged, the differential carrier 1 receives a moment in the vertical direction of the vehicle, the rotational direction, or the like from the bound and rebound of the vehicle, so that the load applied to the elastic body 4 becomes extremely large.

An arrow c shown in FIG. 5 is a moment as a reaction force of the drive torque (rotational torque of the propeller shaft) from the engine, and an arrow d is a torque reaction force from the rear axle shaft (not shown), or The vehicle is bound
This is a moment in the direction in which the differential carrier 1 tilts when rebounding.

A technical problem of the present invention is to suppress the stress concentration on the elastic body in only one direction from two directions and to improve the durability of the elastic body.

(Means for Solving the Problems) Therefore, the present invention takes the following means in order to solve the above-mentioned problems.

That is, in a state in which a diff carrier, to which a propeller shaft is connected and which has a central axis line substantially parallel to the propeller shaft, is kept liquid-tight by an elastic seal material in an axle tube having a central axis line orthogonal to the central axis line. A vibration-isolating support structure for a differential device coupled so as to be relatively displaceable, wherein a plurality of bolts connecting the differential carrier and the axle tube to an outer peripheral portion of the differential carrier,
The bottles are arranged radially around the central axis of the differential carrier, and these bottles are integrally connected to either one of the differential carrier and the axle tube, and the other is connected to the outer peripheral side of the bottle. They are connected via an elastic body fitted so as to be relatively movable in the axial direction.

(Operation) Therefore, in the present invention, a load acts on the differential carrier in a direction along the central axis thereof, in a direction orthogonal to the central axis, in a twisting direction, and in a direction of rotating about the central axis. The bolt connecting the differential carrier and the axle tube is connected to either one of the differential carrier and the axle tube via an elastic body fitted so as to be relatively movable in the axial direction. Only the stress in the compression or shear direction is generated in the elastic body, and the durability thereof is improved.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings. The following embodiment is a case of a banjo type differential device.

FIG. 1 is a front view of a differential device according to an embodiment of the present invention.

In the diff carrier 1, mounting portions 5 integrally formed at four positions on the circumference at the end of the diff carrier 1 are fastened to the stays 6 welded to the axle tube 2 with the bolts 3 via the elastic bodies 8. It is connected to the axle tube 2. The arrangement direction of the bolts 3 is radial from the center of the differential carrier 1.

FIG. 2 shows the first embodiment of the present invention, and is a sectional view taken along the line II-II of FIG. 1 showing a connecting portion between the differential carrier 1 and the axle tube 2.

A thick mounting portion 5 is integrally formed on the differential carrier 1. The mounting portion 5 has an L-shaped flange portion 5a having a hole into which the bolt 3 is inserted when it is assembled to the axle tube 2.
And a spigot portion 5b for positioning is integrally formed. The mounting portion 5 is a screw hole for the bolt 3.
Have 5c.

A stay 6 and a spacer 22 are welded to the axle tube 2. The spacer 22 may be integrally formed with the axle tube 2, and faces the inlay portion 5b of the differential carrier 1 with a clearance. Further, oil seals 11, 11 having a vibration damping effect are interposed between the differential carrier 1 and the mounting portion 5. Although the spigot portion 5b and the spacer 22 interfere with each other when the differential carrier 1 and the axle tube 2 are assembled, they are opposed to each other with a clearance as shown after the assembly.

The stay 6 is provided with a hole 6a, and the bolt 3 and the elastic body 8 are inserted and held in the hole 6a. The elastic body 8 has a cylindrical shape, and is vulcanized and adhered to the outer cylindrical collar 10a and the cylindrical collar 10b, which are also cylindrical. The outer cylinder collar 10a is bonded to the hole 6a of the stay 6, and the inner cylinder collar 10b is attached to the bolt 3
Slidably touches. Both the inner cylinder collar 10b and the outer cylinder collar 10a are made of resin.

In the present invention, as shown in FIG. 4, before the differential carrier 1 and the axle tube 2 are assembled (in a state where the elastic seal material 11 is in contact with the spacer 22 welded to the end of the axle tube 2). The relationship between the distance from the spacer 22 to the center of the bolt hole 5c of the differential carrier 1 (L) and the distance from the center of the hole 6a of the stay 6 on the axle tube 2 side (L1) is L> L1. Then, from the state shown in the drawing, the differential carrier 1 is moved to the right in the drawing while the elastic seal members 11, 11 are contracted, and the bolt hole 5c
The bolt 3 is inserted at a position where the holes of the inner cylinder collar 10b coincide with each other, and the differential carrier 1 and the axle tube 2 are fixed. The elastic force of the elastic body 8 and the elastic sealing materials 11, 11 maintains the fastening force between the differential carrier 1 and the axle tube 2.

Here, a reaction force of the drive torque (rotational torque of the propeller shaft) from the engine shown by the arrow c in FIG. 1, that is, a moment in the direction in which the differential carrier 1 is rotated with respect to the axis of the propeller shaft (not shown) is When applied, the moment acts on the elastic body 8 in the compression direction, and the stress applied to the elastic body 8 is only in one direction, so that stress concentration does not occur locally.

Further, the elastic body 8 receives in the compression direction and the torque reaction force from the rear axle shaft (not shown) from the unillustrated rear axle shaft, that is, the moment in the direction to move the companion flange 9 in the vertical direction. There is only one direction of stress applied to.

Generally, when the vehicle is bound or rebounded, the moment acting on the differential carrier 1 or the axle tube 2 is mainly indicated by the arrow cd. For this reason, the elastic body 8 in the above-described embodiment receives a moment in the compression direction in almost all the states, which facilitates the design of the elastic body 8 having the required strength and is excellent in durability.

If a moment acts to move the diff carrier 1 as a whole in the direction e indicated by an arrow e in FIG. 1, among the elastic bodies 8 at four positions, A and A'opposite each other with respect to the center of the diff carrier 1. A moment in the compression or shearing direction acts on the two elastic bodies 8. The elastic bodies 8 of B and B ′ are
Since the direction of the moment indicated by the arrow e and the axis of the bolt 3 are substantially coincident with each other, the inner cylinder collar 10b and the bolt 3 are slid and no load is applied. When a moment in a direction in which the bolt 3 and the inner cylinder collar 10b cannot slide is applied, the elastic body 8
A force in the shearing direction acts on. The vibration can be damped by sliding the bolt 3 and the inner cylinder collar 10b. Therefore, even when a moment in the direction of the arrow e is generated, only a compressive or shearing stress is generated in the elastic body 8 and a combined stress is not generated, so that the stress is locally concentrated in the elastic body 8. Nothing will happen.

FIG. 3 shows a second embodiment of the present invention. In FIG. 3, parts corresponding to those in FIG. 2 are designated by the same reference numerals as those in FIG. 2 and their description is omitted.

This embodiment is the same as the stay 6 in the first embodiment.
The hole 6a is provided with a protrusion 7 to form a stopper mechanism.

According to this embodiment, when excessive torque is applied to the differential carrier 1 or the axle tube 2, the inner cylinder collar 10b and the protrusion 7 are formed.
The interference between and prevents a large positional displacement between the two. As a result, it is possible to prevent excessive torque from being applied to the elastic body 8, and the durability is further improved. Since the inner cylinder collar 10b is made of resin, the protrusion 7
No interference sound with is generated. Further, the displacement amount of both is determined by adjusting the clearance F.

Further, according to the embodiment of the present invention, since the L-shaped flange portion 5a is formed on the mounting portion 5 of the differential carrier 1, the flange portion 5a can be hooked on the stay 6 and temporarily placed during assembly. This makes assembly work easier. Further, since the elastic body 8 is used only at four places and a small amount is required, the cost can be reduced.

(Effect of the Invention) As described above, according to the present invention, it is possible to suppress the occurrence of stress concentration by restricting the stress applied to the elastic body in only one direction without increasing the number of parts of the elastic body. The durability is improved.

[Brief description of drawings]

1 and 2 show a first embodiment of the present invention. FIG. 1 is an assembled front view of a differential device, FIG. 2 is a partial sectional view of a connecting portion between a differential carrier and an axle tube, and FIG. FIG. 4 is a partial sectional view of a connecting portion between a differential carrier and an axle tube before connecting the differential carrier and the axle tube, and FIG. 5 is an overall perspective view of a conventional differential device. FIG. 6 is a sectional view of a structure in which an elastic body for vibration isolation is interposed in a conventional differential device by a general-purpose method. 1 ... Differential carrier, 2 ... Axle tube, 3 ... Bolt, 4
...... Elastic body, 4a ...... Corner part, 5 ...... Mounting part, 5a ...... Flange part, 5b ...... Inlay part, 5c ...... Screw hole, 6 ...... Stay, 6a ...... hole, 7 ...... Projection part , 8 ... Elastic body, 9 ...
Companion flange, 10a …… Outer cylinder collar, 10b …… Inner cylinder collar, 11 …… Elastic seal material

Claims (1)

[Scope of utility model registration request] 1. A diff carrier, to which a propeller shaft is connected and which has a central axis substantially parallel to the propeller shaft, maintains liquid tightness by an elastic sealing material on an axle tube having a central axis orthogonal to the central axis. In the anti-vibration support structure of the differential device which is connected so as to be relatively displaceable in the above state, a plurality of bolts connecting the diff carrier and the axle tube are radially arranged around the central axis of the diff carrier on the outer peripheral portion of the diff carrier. And each of these bolts is integrally connected to either one of the differential carrier and the axle tube, and the other is fitted to the outer peripheral side of the bolt so as to be relatively movable in the axial direction. A vibration-isolating support structure for a differential device, wherein the vibration-isolating support structure is coupled via an elastic body.