JP2002364634A - Bush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bush 1 capable of suppressing the sliding resistance of both of the bush 1 and a shaft 11 even if foreign matter D1 and D2 intrude between them, and also capable of suppressing the production of noise due to an increase of the sliding resistance. SOLUTION: This bush 1 is provided with an inner peripheral surface 4 brought in contact with the peripheral surface 12 of the relatively rocking or rotating shaft 11 to be freely slid. This bush 1 is provided with a foreign matter eliminating part 5 for eliminating the foreign matter in the inner peripheral surface thereof, and this foreign matter eliminating part 5 is provided with a longitudinal lip 6 and a longitudinal groove 7 formed long in the axial direction. This foreign matter eliminating part 5 stops the foreign matter D1 and D2 with the longitudinal lip 6 and stores them in side of the longitudinal groove 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a bush,
More specifically, the present invention relates to a sliding bush that slides on a shaft.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, a sliding bush provided with a cylindrical inner peripheral surface 52 slidably in contact with a peripheral surface 54 of a shaft 53 which swings or rotates relatively. 5
1 is known, and this bush 51 is integrally formed of urethane rubber, for example, for use in a suspension system in an automobile.

However, in the urethane bush 51 used for swinging sliding, foreign matters (not shown) such as sliding abrasion powder of the bush 51 and the shaft 53, muddy water or earth and sand are used. When there is a gap between the two, the sliding resistance of the two members 51 and 53 increases, and as a result, there is an inconvenience that abnormal noise is likely to be generated during sliding.

[0004]

SUMMARY OF THE INVENTION In view of the above points, the present invention can reduce the sliding resistance between the bush and the shaft even if a foreign object enters between the two, and thus the sliding resistance is increased. An object of the present invention is to provide a bush capable of suppressing generation of abnormal noise.

[0005]

According to a first aspect of the present invention, there is provided a bush having an inner peripheral surface which slidably contacts a peripheral surface of a relatively swinging or rotating shaft. A bush, characterized in that a foreign matter removing portion for removing foreign matter is provided on the inner peripheral surface, and the foreign matter removing portion is provided with a vertical lip and a vertical groove which are long in the axial direction.

[0006] In the bush according to the first aspect of the present invention having the above structure, when foreign matter enters between the bush and the shaft, the foreign matter removing portion provided on the inner peripheral surface of the bush removes the foreign matter. Specifically, the vertical lip stops foreign matter and accumulates in the vertical groove. Therefore, it is possible to substantially remove foreign matter from the sliding portion formed by the combination of the inner peripheral surface of the bush and the outer peripheral surface of the shaft.

[0007] The present application includes the following technical matters.

[0008] That is, in order to achieve the above object, one bush proposed in the present application is provided with a vertical lip and a vertical groove on an inner peripheral surface of a bush used for a suspension of an automobile, etc. Foreign matter is removed from the inner peripheral function surface of the bush to reduce abnormal noise caused by the swinging of the bush. Foreign matter is removed from a shaft in contact with the inner peripheral function surface, and is accumulated in a vertical groove on the inner peripheral surface having no functional influence, thereby suppressing an increase in sliding resistance and reducing abnormal noise.

[0009] The shaft in the present invention includes all components that slide in combination with the bush regardless of the name.

[0010]

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

FIG. 1 shows a bush 1 according to an embodiment of the present invention.
FIG. 2 is a front view of FIG. FIG. 3 is a partially enlarged sectional view taken along line BB in FIG.

The bush 1 according to the present embodiment has a cylindrical inner peripheral surface 4 slidably in contact with the peripheral surface of a shaft that swings or rotates relatively, and is used for an automobile. Used in suspension systems. The bush 1 is integrally formed of urethane rubber, and has the following structure.

That is, first, a flange portion 3 is integrally molded outward at one axial end of a cylindrical portion 2 to specify the entire shape of the bush 1, and an inner peripheral portion of the bush 1 is provided with respect to the peripheral surface of the shaft. An inner peripheral surface 4 that comes into slidable contact is provided. The inner peripheral surface 4 is basically formed in a cylindrical shape that is straight in the axial direction. In the present invention, in particular, the inner peripheral surface 4 is provided with a foreign matter removing portion 5 for removing foreign matter, The foreign matter removing portion 5 includes a longitudinal lip 6 and a longitudinal groove 7 which are long in the axial direction. A portion of the inner peripheral surface 4 where the vertical lip 6 and the vertical groove 7 are not formed is an inner peripheral functional surface 8 that slides on the peripheral surface of the shaft when the bush 1 is operated.

In the foreign matter removing section 5, the vertical lip 6
Is formed as a bead projecting radially inward from the inner peripheral surface 4 of the bush 1.
Is provided over the entire length of the inner peripheral surface 4 along the axial direction. A plurality (twelve in the figure) of the vertical lips 6 are provided at regular intervals in the circumferential direction so as to be evenly arranged. The vertical lip 6 is formed higher than the inner peripheral function surface 8 so as to protrude radially inward from the inner peripheral function surface 8, and has a height from the inner peripheral function surface 8. Is formed to, for example, about 0.2 mm in actual size.

On the other hand, the vertical groove 7 is formed as a concave shape provided on the inner peripheral surface 4 of the bush 1, and like the vertical lip 6, extends along the axial direction of the bush 1. It is provided over the entire length. A plurality (24 in the figure) of the vertical grooves 7 are provided on both sides in the circumferential direction of each vertical lip 6, and the side surface of the vertical lip 6 and the inner side surface of the vertical groove 7 are flush with each other. It is formed continuously. Also,
The depth of the vertical groove 7 from the inner peripheral function surface 8 is, for example, about 0.5 mm in actual size, and the height of the vertical lip 6 (the height of the vertical lip 6 from the inner peripheral function surface 8) and The ratio of the depth of the vertical groove 7 (the depth of the vertical groove 7 from the inner peripheral functional surface 8) is set to about 1: 3.

As shown in FIG. 4 (A), with the shaft 11 passing through the inner periphery of the bush 1 having the above structure, sliding wear powder, muddy water, earth and sand, etc. are interposed between the bush 1 and the shaft 11. When the foreign substances D ₁ and D ₂ enter the bush 1 and the shaft 11 relative to each other (in the direction of arrow E), as shown in the order of FIGS. foreign substance _D 1, _{D 2} is removed, in particular vertical lip 6 into close contact with the peripheral surface 12 of the shaft 11 is blocked foreign matter _D 1, _{D 2,} the swinging direction of the foreign matter _D 1, _{D 2} It is stored in the vertical groove 7 on the front side. Therefore, it is possible to substantially remove the foreign substances D ₁ , D ₂ from the sliding portion formed by the combination of the inner peripheral function surface 8 of the bush 1 and the peripheral surface 11 of the shaft 1, whereby the foreign substances D ₁ , D ₂ It is possible to suppress an increase in the sliding resistance due to the interposition of. Therefore, generation of abnormal noise due to an increase in sliding resistance can be suppressed, or at least the magnitude of the generated abnormal noise can be reduced as compared with the related art.

According to a comparative test conducted by the inventors of the present application, when noise was generated after about 40,000 operations in the conventional product, 200,000 operations were performed according to the bush 1 provided with the foreign matter removing portion 5. The generation of abnormal noise could be suppressed until the time passed, and the effectiveness of the present invention could be confirmed.

In the bush 1 having the above structure,
Since the side surface of the vertical lip 6 is directly connected to the inner surface of the vertical groove 7 and the vertical groove 7 is disposed immediately adjacent to the vertical lip 6,
There is an advantage that foreign matter that the vertical lip 6 blocks is easily stored in the vertical groove 7, and that the vertical lip 6 is easily elastically deformed by such a configuration, so that the vertical lip 6 does not easily increase the sliding resistance. is there.

The structure of the bush 1 can be changed as follows.

In the above embodiment, the vertical lip 6 and the vertical groove 7 are provided along the axial direction of the bush 1 in parallel with the central axis of the bush 1. However, due to their functions, they are formed in a spiral shape. may be, in this case, depending on the setting of such the forming angle, the action of scraping the foreign matters D _1, D ₂ to the outside from the sliding portion can be expected.

In the above-described embodiment, the vertical lip 6 and the vertical groove 7 are provided over the entire length of the bush 1 in the axial direction. These need not be provided at the axial end of the inner peripheral surface 4.

When the vertical groove 7 is provided over the entire length of the bush 1 in the axial direction, a through space formed by the vertical groove 7 is formed between the bush 1 and the shaft 11. When it is desired to eliminate the vertical groove 7, it is preferable to provide a weir portion in the axial direction of the vertical groove 7 by partially not providing the vertical groove 7. In this case, if the formation position of the weir portion is shifted in the axial direction by the plurality of vertical grooves 7 arranged in the circumferential direction, the foreign matter removing action can be secured over the entire length in the axial direction.

In the above embodiment, the vertical groove 7 is
However, when the relative rotation direction of the bush 1 and the shaft 11 is fixed in one direction,
The vertical groove 7 may be provided on only one side of the vertical lip 6. In this case, the vertical groove 7 is provided on the front side of the vertical lip 6 in the direction of relative rotation of the bush 1 with respect to the shaft 11.

The cross-sectional shape of each of the vertical lip 6 and the vertical groove 7 is not particularly limited, but the cross-sectional shape of the vertical lip 6 is set so that the close contact of the vertical lip 6 with the shaft 11 does not significantly increase the sliding resistance. It is desirable that the material be easily elastically deformed when contacting the shaft 11. Therefore, it is preferable that the cross-sectional shape of the vertical lip 6 is a triangle or the like in which the width of the tip is narrowed.

[0025]

The present invention has the following effects.

That is, in the bush according to the first aspect of the present invention having the above-described structure, a foreign matter removing portion for removing foreign matter is provided on an inner peripheral surface thereof, and the foreign matter removing portion has a longitudinal lip and a long longitudinal lip. Since the vertical groove is provided, when foreign matter enters between the bush and the shaft, the foreign matter removing portion removes the foreign matter, and more specifically, the vertical lip blocks the foreign matter and collects the foreign matter in the vertical groove. Become. Therefore, it is possible to substantially remove foreign matter from the sliding portion formed by the combination of the inner peripheral surface of the bush and the outer peripheral surface of the shaft, thereby suppressing an increase in sliding resistance due to the presence of foreign matter. . Therefore, generation of abnormal noise due to an increase in sliding resistance can be effectively suppressed.

[Brief description of the drawings]

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

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a partially enlarged sectional view taken along line BB in FIG. 2;

FIGS. 4A, 4B and 4C are cross-sectional views showing the operation of the bush.

FIG. 5 is a perspective view showing a general combination example of a bush and a shaft.

[Explanation of symbols]

1 bush 2 tubular portion 3 flange 12 peripheral surface inner peripheral surface 5 foreign matter removing portion 6 vertical lip 7 within the longitudinal groove 8 peripheral functional surface 11 the shaft 4 D _{1, D 2} foreign matter

Claims (1)

[Claims] A shaft (11) that relatively swings or rotates.
A bush (1) having an inner peripheral surface (4) slidably in contact with a peripheral surface (12) of the bush, and a foreign matter removing portion (5) for removing foreign matter on the inner peripheral surface (4).
And a longitudinal lip (6) and a longitudinal groove (7) that are long in the axial direction in the foreign matter removing portion (5).