JPH021560Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a bushing used in bearings such as torque rods used in automobiles, railway vehicles, etc.

BACKGROUND OF THE INVENTION Torque rods are used to attach suspension leaf springs, arms, etc. of automobiles and railway vehicles to the vehicle body. This torque rod uses a bushing as a bearing to absorb vibrations.

In conventional bushings, as shown in Figure 4, a buffer member B is fixed to the outer periphery of the inner cylinder A and fitted into the outer cylinder C, so that vibrations, etc. can be damped between the inner cylinder and the outer cylinder. There is something. In this case, the buffer member B has a concave portion formed on the outer periphery of the central portion in the axial direction, so that when a load in the radial direction is applied to the bushing, the concave portion of the buffer member B also comes into contact with the outer cylinder C when the load exceeds a certain level. It's getting old. Therefore, the relationship between the load acting on the bush and the deflection is non-linear as shown in FIG. 3, which prevents excessive deformation of the bush and prevents the bush from becoming fatigued.

Problems to be Solved by the Invention Some conventional bushings have a concave portion formed in the axial center of the cushioning member to make the strain characteristics non-linear with respect to loads in the radial direction. but,
In this case, when a load is applied in the thrust direction, the strain in the thrust direction increases, and when the thrust load is large, there is a problem in that the inner cylinder comes off from the outer cylinder. In addition, in order to prevent this slippage, it has been considered to fix both ends of the buffer member in the axial direction to the inner circumferential surface of the outer cylinder with vulcanization adhesive, etc., but the manufacturing process is complicated and the effectiveness varies. It was stable.

Therefore, the object of the present invention is to make the strain characteristics non-linear with respect to the load in the radial direction acting on the bush, and to prevent the inner cylinder of the bush from slipping out from the outer cylinder in response to the load in the thrust direction.

Means for Solving the Problems In the bearing bush of the present invention, a first buffer member 2 having an annular protrusion 2a at the center in the axial direction is fixed to the inner circumferential surface of an outer cylinder 1 by vulcanization adhesive or the like. . Inner cylinder 3
A second buffer member 4 having annular protrusions 4a at both ends in the axial direction is fixed to the outer circumferential surface of the second buffer member 4 by vulcanization adhesive or the like. A small interval is provided in the radial and thrust directions between the central annular protrusion 2a of the first buffer member 2 and the central recess of the second buffer member 4, so that when a large radial load is applied to the bushing, The central portions of the first and second buffer members are in contact with each other.

The outer cylinder 1 is formed to be slightly larger than the completed size of the bushing, and after fitting onto the outer periphery of the inner cylinder 3, the bushing is assembled by squeezing the outer cylinder 1. Also,
The first buffer member may be provided with annular protrusions at both ends in the axial direction, and the center portion thereof may be formed into a recess, and the second buffer member may be provided with an annular protrusion only in the center portion thereof in the axial direction.

Function When a load in the radial direction is applied to the bush, the annular protrusions 4 at both ends of the second buffer member 4 on the inner cylinder 3 side
a is pressed against the outer cylinder 1 and deformed to provide a buffering effect, and when a large load is further applied in the radial direction, the annular protrusion 2a of the first buffer member 2 on the outer cylinder 1 side becomes the first buffer member 2 on the inner cylinder 3 side. 2. The bushing contacts the central concave portion of the buffer member 4, and a load larger than that will cause a small strain, so the bushing will not be damaged or fatigued over a long period of time even with a large load.

That is, it has nonlinear characteristics with respect to the load in the radial direction, as shown in the graph of load and strain shown in FIG.

When a load in the thrust direction is applied to the bush, the annular protrusions 4 at both ends of the second buffer member 4 on the inner cylinder 3 side
a becomes strained and acts as a buffer, and when a larger load is applied, the two buffer members deform as one,
Two buffer members act in two stages. Moreover, even if a large load in the thrust direction is applied, the annular protrusion 2a of the first buffer member 2 on the outer cylinder 1 side
Since it hits the annular protrusion 4a at both ends, there is no chance of it slipping out.

Example An embodiment of the present invention will be explained with reference to FIG.

A first buffer member 2 made of rubber, synthetic resin, or the like is fixed to the inner peripheral surface of the cylindrical outer cylinder 1 by vulcanization adhesive or the like. The buffer member 2 has an axially central portion formed into an annular protrusion 2a that protrudes inward. In addition,
The outer cylinder 1 and the buffer member 2 are formed to have a slightly larger diameter than the finished size of the bushing, and after fitting into the inner cylinder described later, the outer cylinder is squeezed to the finished size.

A second buffer member 4 made of rubber, synthetic resin, or the like is fixed to the outer peripheral surface of the cylindrical inner tube 3 by vulcanization adhesive or the like. The buffer member 4 is formed into an annular protrusion 4a that protrudes outward at both ends in the axial direction. The outer circumferential surface of this annular protrusion 4a is in contact with the inner circumferential surface of the buffer member 2 on the outer cylinder side, but the central recess of the buffer member 4 on the inner cylinder side is in contact with the annular protrusion 2a of the buffer member on the outer cylinder side. A small interval is left in the radial direction between the inner tube and the inner tube, and only the annular protrusion 5 provided at the center of the buffer member 4 on the inner cylinder side comes into contact with the annular protrusion 2a. The annular protrusion 5 prevents the two buffer members 2 and 4 from suddenly coming into contact with each other, so that the buffer state does not change suddenly. Further, the annular protrusion 2 of the buffer member 2
A small interval is also provided in the thrust direction between the annular members 4a at both ends of the buffer member 4, so that when a large load is applied in the thrust direction, the two buffer members act as buffers.

A guide 6 is provided at the center in the axial direction of the inner circumference of the inner cylinder 3, and a bearing 7 made of strong synthetic resin, an oil-impregnated fabric 8, and a ring 9 are provided in order on both sides of the guide 6. A pin 10 is inserted into the inner periphery of the pin 10 so that the pin 10 can rotate. The ring 9 is fixed by protrusions 11 such as caulking, and dust covers 12 made of rubber or the like are provided on the inner periphery of both ends of the inner cylinder 3.

Although a bush having a rotation mechanism is formed with the above configuration, the same method can be applied to a bush without a rotation mechanism as shown in FIG.

In addition, in the above embodiment, since the buffer member on the outer cylinder side and the buffer member on the inner cylinder side are manufactured separately, by making their rubber hardness different,
The relationship between load and strain on the bushing can be arbitrarily selected, and nonlinear characteristics can be increased.

Further, the first buffer member may be provided with an annular protrusion at both ends in the axial direction, and the center portion may be formed into a recess, and the second buffer member may be provided with an annular protrusion only in the center portion in the axial direction. .

Effects of the invention As described above, this invention has two
Since one of the two shock absorbing members has its axially central portion protruding, and the other has its axially opposite end portions protruding, the bush has a non-linear relationship between strain and load in the radial direction. Therefore, the buffer member is prevented from being excessively deformed under a load exceeding a predetermined value, and its fatigue characteristics can be improved. In addition, when a small load in the thrust direction is applied to the bushing, it is sufficiently buffered by the deformation of the buffer member having a central recess and the frictional force acting between both buffer members, and when an excessive load is applied to the bushing, the outer cylinder side Since each annular protrusion of the buffer member on the inner cylinder side provides a buffer, a large load is not applied to the buffer member immediately after a load is applied, and the inner cylinder does not slip out of the outer cylinder. Further, by appropriately selecting different hardnesses of the buffer members fixed to the inner tube and the outer tube, arbitrary nonlinear characteristics can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a bushing with a rotating mechanism of the present invention, Fig. 2 is a half sectional view of a bushing without a rotating mechanism, Fig. 3 is a graph showing the nonlinear characteristics of the bushing, and Fig. 4 is a conventional bushing. FIG. 1; Outer cylinder, 2; Buffer member, 2a; Annular protrusion,
3: Inner cylinder, 4: Buffer member, 4a: Annular protrusion.

Claims (1)

[Claims for Utility Model Registration] (1) In a bush that is used as a shock absorbing bearing such as a torque rod by providing a buffer member between the inner cylinder and the outer cylinder, the inner peripheral surface of the outer cylinder and the outer peripheral surface of the inner cylinder are On one side, a first buffer member having an annular protrusion at the center in the axial direction is fixed by vulcanization adhesive, etc., and on the other side, a second buffer member having annular protrusions at both ends in the axial direction is fixed by vulcanization adhesive, etc. A bushing for a bearing that is fixedly fixed to the bearing bushing, and has a central annular protrusion of a first shock absorbing member and a central recess of a second shock absorbing member facing each other with a small interval in the radial direction and the thrust direction. (2) The bushing for a bearing according to claim 1, wherein the hardness of the first buffer member and the hardness of the second buffer member are different. (3) The bushing for a bearing according to claim 1 or 2 of the utility model registration claim, in which a small annular protrusion is provided in the center of the second buffer member and is in contact with the annular protrusion of the first buffer member.