JPH11101304A - Manufacture of bush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To expand the settable area of a spring constant set for each of the diameter direction, axial direction, twist direction and prizing direction of a bush, on the manufacture of the bush for connecting a cylindrical outer periphery side member with the outer periphery side of an inner periphery side member through an elastic body. SOLUTION: The diameter size of the axial direction center part 3a of an outer periphery side member 3 is set to larger than the diameter size at the manufacturing finish time and also the axial direction end part 3b of the outer periphery side member 3 is molded in a taper shape toward an oblique inside and then the outer periphery side member 3 is arranged to the outer periphery side of an elastic body 2 and then the axial direction center part 3a is drawn up to a prescribed diameter size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for manufacturing a bush.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, there is known a bush in which a cylindrical outer peripheral member 53 is connected to an outer peripheral side of an inner peripheral member 51 via an elastic body 52 made of a rubber-like elastic material. The bush serves as a vibration damping mechanism or a vibration damping mechanism that attenuates input vibration using the elasticity of the elastic body 52.
It is used for various purposes.

[0003] The above bush is conventionally manufactured by the following method.

That is, first, the inner peripheral member 51 and the outer peripheral member 53 are each formed into a final product shape, and then these two members 51 and 53 are vulcanized for forming the elastic body 52. Put into mold cavity. Next, the elastic body 52 is vulcanized and molded by the vulcanization mold, and the outer peripheral surface of the inner peripheral member 51 and the outer peripheral member 5 are simultaneously formed with the vulcanization molding.
3 is vulcanized and adhered to the inner peripheral surface to obtain a bush shown in FIG.

[0005] However, since no compression is applied to the vulcanized elastic body 52 in the bush manufactured by such a method, a radial direction of the bush is not increased.
There is a problem that the settable region (characteristic settable region) of the spring constant set in each of the axial direction, the torsional direction (x direction) and the twisting direction (y direction) is limited to a relatively narrow range.

[0006]

SUMMARY OF THE INVENTION In view of the above, the present invention relates to the manufacture of a bush for connecting a cylindrical outer peripheral member to an outer peripheral side of an inner peripheral member via an elastic body. It is an object to expand a settable region (characteristic settable region) of a spring constant which is set in each of a radial direction, an axial direction, a torsion direction, and a twisting direction of the bush by applying compression to a part of the bush.

[0007]

In order to achieve the above-mentioned object, a method of manufacturing a bush according to the present invention is directed to a method of manufacturing a bush, wherein an outer peripheral side of an inner peripheral side member is provided with an elastic member made of a rubber-like elastic material. In the method of manufacturing a bush, the axial dimension of the outer peripheral member is set to be larger than the diameter at the end of the production, and the axial end of the outer peripheral member is tapered obliquely inward. Then, the outer peripheral side member is arranged on the outer peripheral side of the elastic body, and then the central portion in the axial direction is subjected to drawing processing until a predetermined diameter is obtained.

When a part of the elastic body is compressed during the manufacturing process, the spring constant can be increased to reduce the hardness. However, in the present invention, in particular, the diameter of the axially central portion of the outer peripheral member is reduced. It is set to be larger than the diameter at the end of production, and the axial end of the outer peripheral member is formed into a tapered shape obliquely inward, and then the outer peripheral member is disposed on the outer peripheral side of the inner peripheral member and the elastic body. In addition, since only the former central portion in the axial direction is drawn until a predetermined diameter (diameter at the end of production) is obtained, the outer peripheral member is positioned on the inner peripheral side of the central portion in the axial direction. The radial compression is applied only to the axial center portion of the elastic body. Therefore, as a result, a characteristic is obtained in which the spring constant at the axial center portion of the elastic body increases, but the spring constant at the axial end portion of the same elastic body does not increase. A large damping effect can be expected.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 are half sectional views of a bush manufactured by the manufacturing method according to the embodiment. FIG. 1 shows a state in the middle of manufacture, and FIG. 2 shows a state in the end of manufacture. I have.

[0011] The bush manufactured by the method is as follows.
As shown in FIG. 2, a cylindrical elastic member (also referred to as rubber) made of a rubber-like elastic material is provided on the outer peripheral side of an inner peripheral member (also referred to as an inner sleeve) 1 made of a rigid material such as metal.
An outer peripheral side member (also referred to as an outer sleeve) 3 made of a rigid material such as a sheet metal having a cylindrical shape and connected concentrically via the center 2. It functions as a mechanism or an anti-vibration mechanism.

The bush shown in FIG. 2 is manufactured as follows.

First, as shown in FIG. 1, the dimensions are set such that the diameter φA of the axially central portion 3a of the outer peripheral member 3 is larger than the diameter φB (see FIG. 2) at the end of the production. The outer peripheral member 3 is formed into a cylindrical shape, and at the same time, the axial ends 3b of the outer peripheral member 3 are each formed into a tapered shape obliquely inward. Also, the inner peripheral member 1
Is formed into a final product shape.

Next, the outer peripheral member 3 and the inner peripheral member 1 are respectively put into cavities of a vulcanization mold (not shown) for molding the elastic body 2.

Next, the elastic body 2 is vulcanized and molded by the vulcanization mold, and is simultaneously vulcanized and bonded to the outer peripheral surface of the inner peripheral member 1 and the inner peripheral surface of the outer peripheral member 3 simultaneously with the vulcanization molding.
This results in the state of FIG. The inner peripheral surface of the outer peripheral side member 3 includes an inner peripheral surface of the axial central portion 3a and each axial end 3b.
Of the inner peripheral surface.

Next, the axially central portion 3a of the outer peripheral side member 3
Is drawn by a machine such as a roller or a jig (not shown) until a predetermined diameter (diameter φB at the end of the production) is obtained over the entire length L in the axial direction. The indicated bush is manufactured.

The axial end portions 3b of the outer peripheral member 3 formed into a tapered shape automatically return to a cylindrical shape due to a relative displacement with respect to the axial central portion 3a due to the drawing process. The reason for this is to apply radial compression only to the axial center portion 2a of the elastic body 2 by drawing and not to apply compression to the axial end 2b of the same elastic body 2. Also, when the axial end 3b is automatically returned in this way, the axial end 2b of the elastic body 2 is pulled radially outward, and the hardness difference from the axial center 2a is further promoted. There is also.

When a bush is manufactured by such a method, a part of the elastic body 2 is radially compressed during the manufacturing process.
The settable region (characteristic settable region) of the spring constant set in each of the axial direction, the torsional direction (x direction) and the twisting direction (y direction) can be expanded as compared with the case where the elastic body is not compressed. Therefore, it becomes easy to realize the characteristics required as product specifications.

In addition, according to this method, radial compression is applied only to the axial central portion 2a of the elastic body 2 located on the inner peripheral side of the axial central portion 3a of the outer peripheral member 3 to be drawn. As a result, since the axial end 2b of the same elastic body 2 is not compressed, the spring constant of the axial central portion 2a of the elastic body 2 increases, but the spring constant of the axial end 2b does not increase. Characteristics can be obtained, and thereby a large damping effect can be expected for vibration input in the twisting direction.

[0020]

The present invention has the following effects.

That is, in the method of manufacturing a bush according to the present invention, since a radial compression is applied to a part of the elastic body during the manufacturing process, each of the radial direction, the axial direction, the torsional direction and the twisting direction of the bush is different. The area in which the spring constant can be set (the area in which the characteristic can be set), which is set for, can be expanded as compared with the case where the elastic body is not compressed, and the characteristics required as product specifications can be easily realized.

In addition, according to the bush manufacturing method of the present invention, radial compression is applied only to the axial center portion of the elastic body located on the inner circumferential side of the axial center portion of the outer peripheral member to be drawn. In addition, since the axial end of the same elastic body is not compressed, the spring constant at the axial center of the elastic body increases, but the spring constant at the axial end does not increase. Thus, a large damping effect can be expected for vibration input in the twisting direction.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing a state in the middle of manufacturing a bush manufactured by a manufacturing method according to an embodiment of the present invention.

FIG. 2 is a half sectional view showing a state of the bush at the time of completion of manufacture.

FIG. 3 is a half sectional view of a bush manufactured by a conventional manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inner peripheral member 2 Elastic body 2a, 3a Axial center part 2b, 3b Axial end part 3 Outer peripheral member

Claims (1)

[Claims] 1. A method of manufacturing a bush in which a cylindrical outer peripheral member (3) is connected to an outer peripheral side of an inner peripheral member (1) via an elastic body (2) made of a rubber-like elastic material. The diameter of the central portion (3a) in the axial direction of the side member (3) is set to be larger than the diameter at the end of the production, and the axial end (3b) of the outer peripheral member (3) is directed obliquely inward. Forming into a taper shape, then disposing the outer peripheral side member (3) on the outer peripheral side of the elastic body (2), and then drawing the central portion (3a) in the axial direction until a predetermined diameter is obtained. A method for producing a bush, which is characterized by the following.