JP2590378Y2 - Dust seal for joint structures capable of swinging or spherical motion - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust seal mounted between a shaft capable of swinging or spherical movement and a cylindrical housing surrounding the shaft. More specifically,
In the present invention, a bellows part is attached to a joint structure, which is called a pillow ball bush or a suspension link bush, and includes a shaft capable of swinging or spherical movement and a cylindrical housing surrounding the shaft. The present invention relates to a dust seal that is used after being inverted.

[0002]

2. Description of the Related Art In some cases, a joint structure called a pillow ball bush or a suspension ring bush capable of swinging or spherical motion is used for a connection portion of a suspension that connects a tire of an automobile to a vehicle body.
A dust seal is provided between the shaft of the bush and the housing to prevent intrusion of muddy water and the like. This dust seal is basically a mounting part that fits into the housing, a seal lip that slides into contact with the shaft, and a bellows part that connects the mounting part and the seal lip and deforms in response to the spherical motion of the bush, etc. And

[0003] As such a dust seal, conventionally,
As shown in FIG. 5, the mounting portion 201 and the seal lip 20
The bellows portion 203 connecting to the shaft 2 is formed in a U-shape in advance to provide a bent portion b so that the seal lip 202 can follow the inclination and reciprocation of the shaft of the assembly partner.

FIG. 3 shows a conventional dust seal.
As shown in (A) of FIG.
01, a straight conical bellows portion 103 is projected in the insertion direction (the direction indicated by the arrow in the drawing), and a seal lip portion 102 that comes into sliding contact with the shaft is provided at the tip thereof. The bellows portion 103 is previously inverted by hand or the like as shown in FIG. 3B, and then assembled between the housing 110 and the shaft 111 as shown in FIG.

[0005]

However, the dust seal structure shown in FIG. 5 has a drawback that the life is short because the deformation stress due to the bending of the bellows portion 203 is always concentrated near the bellows bending point b. .

The dust seal structure shown in FIG. 3 in which the bellows portion 103 is inverted is used to prevent the stress concentration point from being fixed. However, after the bellows portion 103 is inverted, the mating parts (housing 110, shaft In the case of assembling in step (111), it is necessary to invert the bellows part 103 manually, which involves a troublesome work.
In addition, there is an individual difference in the amount of return of the bellows portion 103 with respect to the reverse deformation and, in turn, the position of the seal lip portion 102 from a certain reference position. Further, depending on the size of the dust seal, it may be difficult for a manufacturer or a user to invert the bellows portion 103 in advance before assembling the dust seal.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a dust seal having a structure in which a bellows part can be automatically inverted at the same time as being assembled to a mating part.

[0008]

In order to achieve the above object, the present invention is provided between a shaft capable of swinging or spherical movement and a cylindrical housing surrounding the shaft, and fitted to the housing. In a dust seal in which a conical bellow portion extending toward the shaft side from the mounting portion to be turned is turned over and a seal lip portion provided at the tip thereof is brought into contact with the shaft, the seal lip portion is further radially inward than the seal lip portion. A support portion having an inner diameter smaller than that of the shaft extending toward is provided.

[0009]

When the dust seal is inserted into the housing, the support portion first comes into contact with the end face of the shaft and is caught. In this state, if the user tries to insert the mounting portion into the housing by press fitting or the like, the bellows portion is relatively pulled in the direction opposite to the insertion direction, and is eventually inverted. Further, as the mounting portion is pushed into the housing, the seal lip at the tip of the inverted bellows portion comes into sliding contact with the shaft. Then, when the mounting portion is set at a predetermined position of the housing, the seal lip portion is fitted to the shaft while the bellows portion is inverted and deformed into a V shape.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of the present invention will be described below in detail with reference to the embodiments shown in the drawings.

FIG. 1 shows an example in which the present invention is applied to a dust seal of a suspension pillow ball bush for an automobile. This dust seal has a mounting portion 1 fitted to a housing 10 of a pillow ball bush, a seal lip portion 2 slidably in contact with a shaft 11 of the bush, and a spherical motion by connecting and reversing the mounting portion 1 and the seal lip portion 2. And a support portion 4 and a reinforcing ring 5 formed further inward in the radial direction than the seal lip portion 2.

At the boundary between the seal lip portion 2 and the support portion 4, a cut 6 is formed on a surface on the opposite side to the seal lip portion 2 being formed, that is, on a surface on which the dust seal is pushed into the shaft 11 of the bush. The support portion 4 is provided so that the support portion 4 can be easily separated from the seal lip portion 2 after the dust seal is inserted and mounted between the housing 10 and the shaft 11 of the pillow ball bush.

The bellows portion 3 has a conical shape protruding from the mounting portion 1 in the direction (arrow direction) of inserting the dust seal into the pillow ball bush, and has a seal lip portion 2 at its tip. The bellows portion 3 has such a rigidity and elasticity that the dust seal can be inverted to maintain a V-shape when the dust seal is inserted into the pillow ball bush.

With the above configuration, the mounting portion 1
When the support lip is mounted on the housing 10 side, the support portion 4 inside the seal lip portion 2 comes into contact with the shaft 11 on the other side, and this becomes an obstacle to deform the bellows portion 3 so that the seal lip portion is turned. 2 is inserted in a state of being in contact with the shaft 11 while being inverted. For this reason, the bellows part 3 is in a state where the mounting part 1 is completely inserted into the housing 10.
It bends in the middle and the cross-sectional shape is inverted into a V-shape. Then, due to the shape change due to the inversion of the bellows portion 3, an elastic force is applied to the seal lip portion 2 so as to be constantly pressed against the shaft 11. Here, the support portion 4 has a swinging rotation between the housing 10 and the shaft 11 within a small range, for example, 5 °.
If the angle is only 10 ° to 10 °, there is no problem even if it is used while being attached to the seal lip portion 2 as it is. However, when the swing rotation is performed to some extent, the support portion 4 may be separated after the mounting. In this case, the support portion 4 is automatically separated by swinging rotation between the housing 10 and the shaft 11, or is separated by an operator removing the support portion 4.

The above-described embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited thereto, and various modifications can be made without departing from the gist of the present invention. For example, by forming the bellows portion 3 formed at the tip of the seal lip portion 2 into a right cone having an inner diameter smaller than the diameter of the shaft 11, the seal lip portion 2 also serves as a support portion in contact with the end portion of the shaft 11. You may do it. Further, in this embodiment, the present invention is applied to a dust seal used for a suspension pillow ball for an automobile. However, the present invention is not limited to this, and is mounted between two members capable of swinging or spherical motion, reciprocating motion, and the like. Of course, it can be applied to all dust seals.

[0016]

As is apparent from the above description, in the dust seal of the present invention, the seal lip is provided with the support portion having an inner diameter smaller than the axis extending further inward in the radial direction than the seal lip. In addition, the support portion inside the seal lip portion comes into contact with the mating shaft at the time of assembling to the mating component, thereby causing an obstruction.

Therefore, the work of mounting the dust seal becomes extremely easy. Further, even if the dust seal has a small diameter, it is possible to mount the bellows portion by inverting the bellows portion.

[Brief description of the drawings]

FIG. 1 is an axial plan sectional view showing one embodiment of a dust seal of the present invention.

FIG. 2 is an axial plan sectional view illustrating a state where the dust seal of FIG. 1 is mounted on a mating component.

FIG. 3 is a drawing showing an example of a conventional dust seal.
(A) is an axial plan sectional view of the dust seal, and (B) is an axial plan sectional view in a state where a bellows portion of the dust seal is inverted.

4 is an axial plan sectional view illustrating a state where the dust seal of FIG. 3 is mounted on a mating component.

FIG. 5 is an axial plan sectional view showing another example of the conventional dust seal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Attachment part 2 Seal lip 3 Bellows part 4 Support part 10 Housing 11 axis

Claims (1)

(57) [Scope of request for utility model registration] 1. A conical shape which is mounted between a shaft capable of swinging or spherical motion and a cylindrical housing surrounding the shaft and extends from a mounting portion fitted to the housing toward the shaft. In a dust seal in which the bellows portion is inverted and a seal lip portion provided at the tip thereof is brought into contact with the shaft, the seal lip portion has an inner diameter smaller than the shaft extending further inward in the radial direction than the seal lip portion. A dust seal characterized by having a support section.