JPH055290Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a dust cover for a ball joint, and particularly to a dust cover for a ball joint that has excellent sealing properties against moisture.

[Prior art and its problems]

Generally, a dust cover for a ball joint used in a suspension system or a steering system of an automobile is constructed as shown in FIG.

That is, inside the socket 23, there is a columnar part 2.
The spherical part 22b of the ball stud 22, in which the ball stud 2a and the spherical part 22b are integrally formed, is rotatably fitted through a ball seat 24 made of synthetic resin or the like, and the columnar part of the ball stud 22 A cylindrical dust cover 25 with both ends open is fitted around the socket 22a, and the opening at one end of the dust cover 25 is fitted with a fixing band in a recess formed in the outer peripheral portion of the socket 23. 29.

On the other hand, an annular reinforcing member 2 having an L-shaped cross section inside
The opening at the other end of the dust cover 25 has a seal lip 26 embedded therein and a seal lip 26 having an uneven cross section formed on the inner circumference.
It is attached in a state in which it is slidably abutted on the outer peripheral surface of the columnar portion 22a.

Further, the columnar portion 22a of the ball stud 22
A knuckle arm 28 is fixed by a bolt nut while pressing an annular protrusion formed on the outer periphery of the opening at the other end of the dust cover 25.

In the above-mentioned conventional device, when the ball stud 22 makes a complicated movement by combining rocking and rotation with respect to the socket 23, the dust cover 25 follows the movement of the ball stud 22. At the same time, the ball stud 2
A seal lip 26 formed at one opening on the second side slides on the outer peripheral surface of the columnar part of the ball stud 22 to seal between the ball stud 22 and the dust cover 25.

However, in the case of the conventional type mentioned above, the deterioration of the dust cover progresses as the usage period becomes longer.
In particular, it is known that the sealing performance of this part tends to deteriorate due to significant wear on the seal lip, but since factors such as handling and frequency of use have a complex influence, it is important to consider when it is time to replace parts. It is difficult to know in advance, and it is not obvious from the outside that the sealing performance has deteriorated, so people are currently using the product without noticing that the sealing performance has deteriorated.

For this reason, especially when used in situations where there is a risk of moisture intrusion, such as during rainy weather, there is a risk that moisture will infiltrate the inside of the dust cover, making it impossible to maintain the function of the ball joint and leading to a serious accident. It had the following problems.

This invention solves the problems of the above-mentioned devices, and even if the seal lip of the dust cover is worn out, the sealing performance between the dust cover and the ball joint can be maintained at all times, and the ball joint The purpose is to provide a dust cover for ball joints that can maintain the functionality and durability of the ball joint.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention is a dust cover that is fitted with a ball joint that is attached to a socket and has a ball stud that swings and rotates with respect to the socket. has a cylindrical shape with both ends open, and
means for attaching an opening at one end to the socket side, attaching an opening at the other end to the ball stud side, and arranging a seal ring made of highly absorbent rubber at a portion of the dust cover that comes into contact with the ball stud; This is what was adopted.

[Action]

By adopting the above-mentioned method, the seal ring made of highly absorbent rubber expands when moisture adheres to it, so even if the opening of the dust cover that contacts the ball stud is worn out, this part will not be damaged. It is possible to maintain sealing performance and prevent moisture from entering inside the ball joint. [Example] Hereinafter, an example of this invention shown in the drawings will be described.

1 and 2 show a first embodiment of the dust cover for a ball joint according to this invention, and inside the socket 3 there is a ball formed integrally with a columnar part 2a and a spherical part 2b. The ball upper part 2b of the stud 2 is rotatably fitted through a ball seat 4 made of synthetic resin or the like, and
A cylindrical dust cover 5 with both ends open is fitted around the columnar part 2a of the ball stud 2, and the opening at one end of the dust cover 5 is formed on the outer periphery of the socket 3. It is fixed to the recessed portion by a fixing band 9.

On the other hand, an annular reinforcing member 7 having an L-shaped cross section inside
The opening at the other end of the dust cover 5 has a seal lip part 6 buried therein and a seal lip part 6 having an uneven cross section formed on the inner circumference. 2
It is attached so as to be slidably in contact with the inner circumferential surface of a.

Further, the dust cover 5 of the seal lip portion 6
The end opposite to the inside is cut out in an annular shape,
This cutout portion and the columnar portion 2 of the ball stud 2
In the annular gap formed by a, there is a seal ring made of highly water-absorbent rubber in which a highly water-absorbent resin such as acrylic acid-vinyl alcohol copolymer is dispersed in the rubber, and whose cross section is rectangular. 10
is inserted, and on the other hand, the ball stud 2
A knuckle arm 8 is fixed to the columnar portion 2a by a bolt nut while pressing an annular protrusion formed on the outer periphery of the opening at the other end of the dust cover 5.

In the above case, when the ball stud 2 makes a complicated movement that combines rocking and rotation with respect to the socket 3, the dust cover 5 follows the movement of the ball stud 2. At the same time, the seal lip 6 formed in one opening and the seal ring 10 slide on the outer peripheral surface of the columnar part 2a of the ball stud 2 to seal between the ball stud 2 and the dust cover 5. There is.

With the above configuration, it can be used in situations where there is a risk of moisture intrusion, such as during rainy weather, without noticing that the sealing performance between the seal lip part and the columnar part of the ball stud has deteriorated. Even in such a case, the seal ring made of super absorbent rubber will expand due to moisture adhering to the seal part, and since the annular reinforcing member is located in the outer circumferential direction, the seal ring will expand in the inner circumferential direction. Therefore, the sealing performance between the seal lip portion and the columnar portion of the ball stud is improved, and the function and durability of the ball joint can be maintained.

Furthermore, the method of attaching the seal ring can be easily improved since it is only necessary to cut out a portion of the end of the seal lip of the conventional dust cover and fit it into this portion.

FIG. 3 shows a second embodiment of the ball joint dust cover according to this invention, and in this second embodiment, the seal lip portion 6 of the dust cover 5 according to the first embodiment is The shape of the attached seal ring 10 is improved,
The rest of the configuration is the same as that of the first embodiment, so a detailed explanation will be omitted.

That is, in the annular gap formed between the columnar portion 2a of the ball stud 2 and the cutout portion formed at the end of the seal lip portion that abuts the columnar portion 2a (not shown) of the ball stud 2, the acrylic A seal ring 20 is made of highly water-absorbent rubber in which a highly water-absorbent resin such as an acid-vinyl alcohol copolymer is dispersed in the rubber, and has a circular cross section.
is inserted.

In the above case, when the ball stud 2 makes a complicated movement with respect to the socket 3 by combining rocking and rotation, the dust cover 5 follows the movement of the ball stud 2 and The seal lip 6 formed in one opening and the seal ring 20 slide on the outer peripheral surface of the columnar part 2a of the ball stud 2 to seal between the ball stud 2 and the dust cover 5. .

With the above configuration, it can be used in situations where there is a risk of moisture intrusion, such as during rainy weather, without noticing that the sealing performance between the seal lip and the columnar part of the ball stud has deteriorated. Even in such a case, the seal ring made of highly water-absorbent rubber will expand due to moisture adhering to the seal part, and since the annular reinforcing member is located in the outer circumferential direction, the seal ring will expand in the inner circumferential direction. Therefore, the sealing performance between the seal lip portion and the columnar portion of the ball stud is improved, and the function and durability of the ball joint can be maintained.

In addition, the method for attaching the seal ring can be easily improved by simply cutting out a part of the end of the seal lip of the conventional dust cover and fitting it into this part. It also has the advantage of being easy to fit.

FIG. 4 shows a third embodiment of the ball joint dust cover according to this invention, and in this third embodiment, the seal lip portion 6 of the dust cover 5 according to the first and second embodiments is The seal ring 10 attached to the first embodiment and its attachment position are changed, and the other configurations except for the shapes of the reinforcing member and the dust cover are the same as those of the first embodiment, so a detailed explanation will be omitted.

That is, an annular reinforcing member 17 made of resin is embedded inside the opening located on the columnar part 2a (not shown) side of the ball stud 2, and a cross section is formed in the inner circumference of the opening. An uneven seal lip portion is formed, and the end portion of this portion facing the inside of the dust cover 5 is partially cut out into an annular shape.

In the cutout part, a seal ring 30 made of highly water-absorbent rubber in which a highly water-absorbent resin such as acrylic acid-vinyl alcohol copolymer is dispersed in the rubber and having a rectangular cross section is installed using cyanoacrylate. It is bonded with an instant adhesive such as a type of adhesive.

In the above case, when the ball stud 2 makes a complicated movement with respect to the socket 3 by combining rocking and rotation, the dust cover 5 follows the movement of the ball stud 2 and A seal lip formed in one opening and the seal ring 30 slide on the outer peripheral surface of the columnar part 2a of the ball stud 2 to seal between the ball stud 2 and the dust cover 5.

With the above configuration, it can be used in situations where there is a risk of moisture intrusion, such as during rainy weather, without noticing that the sealing performance between the seal lip part and the columnar part of the ball stud has deteriorated. Even in such a case, the seal ring made of super absorbent rubber will expand due to moisture adhering to the seal part, and since the annular reinforcing member is located in the outer circumferential direction, the seal ring will expand in the inner circumferential direction. Therefore, the sealing performance between the seal lip portion and the columnar portion of the ball stud is improved, and the function and durability of the ball joint can be maintained.

Furthermore, the method of attaching the seal ring can be easily improved since it is only necessary to cut out a portion of the end of the seal lip of the conventional dust cover and adhere to this portion.

FIG. 5 shows a fourth embodiment of this invention, in which a retainer 11 is provided inside the socket 3.
The spherical part 2b of the ball stud 2 is integrally formed with the columnar part 2a and the spherical part 2b, which are integrally attached, and the ball seat 4 is made of synthetic resin or the like.
A cylindrical dust cover 15 with both ends open is fitted around the columnar part 2a of the ball stud 2.

The opening at one end of the dust cover 15, in which the annular tightening ring 12 is embedded, is attached to a recess formed in the outer circumference of the socket 3. The opening at the other end of the dust cover 15 has an annular reinforcing member 7 embedded therein and has a seal lip 16 on its inner periphery. The retainer 2a is attached so as to be slidably in contact with the outer peripheral surface of the retainer 11 that is integrally attached to the retainer 2a.

The end portion of the seal lip portion 16 facing the inside of the dust cover 15 is cut out in an annular shape, and an annular shape formed by this cutout portion and a portion bent toward the outer circumferential direction of the retainer 11 is formed. A seal ring 40 made of highly water-absorbent rubber in which a highly water-absorbent resin such as an acrylic acid-vinyl alcohol copolymer is dispersed in the rubber and has a circular cross section is fitted into the gap. A knuckle arm 8 is fixed to the columnar portion 2a of the ball stud 2 by a bolt nut while pressing an annular protrusion formed on the outer periphery of the opening at the other end of the dust cover 15.

In the above case, when the ball stud 2 makes a complicated movement with respect to the socket 3 that combines rocking and rotation, the dust cover 15 follows the movement of the ball stud 2. At the same time, the seal lip portion 16 formed at one opening and the seal ring 40 slide on the outer peripheral surface of the retainer 11 that moves together with the columnar portion 2a of the ball stud 2, thereby connecting the ball stud 2 and the dust cover 15. There is a seal between the two.

By configuring as described above, there is no risk of moisture entering during rainy weather without noticing that the sealing performance between the seal lip and the retainer attached to the columnar part of the ball stud has deteriorated. Even if it is used under certain conditions, the seal ring made of highly absorbent rubber will expand due to moisture adhering to the seal part, and because there is an annular reinforcing member located in the outer circumferential direction. Since the ball expands only in the inner circumferential direction, it is possible to improve the sealing performance between the seal lip part and the retainer attached to the columnar part of the ball stud and maintain the function and durability of the ball joint. Become.

In addition, the method for attaching the seal ring can be easily improved by simply cutting out a portion of the end of the seal lip of the conventional dust cover and fitting it between the cutout and the retainer. can.

[Effect of idea]

By configuring the present invention as described above,
Made of highly water-absorbent rubber, it can be used in situations where moisture may enter, such as during rainy weather, without noticing that the seal between the dust cover and the ball stud of the ball joint has deteriorated. Since the seal ring absorbs moisture and expands, it can prevent moisture from entering the inside of the ball joint, resulting in superior effects such as maintaining the functionality and durability of the ball joint. It is something that you have.

[Brief explanation of the drawing]

Fig. 1 is an overall schematic cross-sectional view showing the first embodiment of the dust cover for ball joint according to this invention, Fig. 2 is an enlarged schematic cross-sectional view showing the main part of Fig. 1, and Fig. 3 is a ball joint dust cover. FIG. 4 is an enlarged schematic sectional view of the main parts showing the second embodiment of the dust cover for
The figure is an enlarged schematic sectional view of the main parts showing the third embodiment of the dust cover for a ball joint, FIG. 5 is an overall schematic sectional view showing the fourth embodiment of the dust cover for a ball joint, and FIG. 1 is an overall schematic sectional view showing a conventional dust cover for a ball joint. 1, 21... ball joint, 2, 22...
Ball stud, 2a, 22a... columnar part, 2
b, 22b...spherical part, 3, 23... socket,
4, 24... Ball seat, 5, 15, 25...
Dust cover, 6, 16, 26... Seal lip portion, 7, 17, 27... Reinforcement member, 8, 28...
Natsukuru arm, 9, 29...Fixing band, 1
0, 20, 30, 40... Seal ring, 11...
...Retainer, 12...Tightening ring.

Claims (1)

[Scope of utility model registration request] The dust cover 5 has a cylindrical shape with both ends open, and is fitted with a ball joint 1 having a ball stud 2 which is attached to a socket 3 and swings and rotates with respect to the socket 3. At the same time, the opening at one end is attached to the socket 3 side, and the opening at the other end is attached to the ball stud 2.
A dust cover for a ball joint, which is attached to the side of the ball joint, and seal rings 10, 20, 30, and 40 made of highly water-absorbent rubber are provided at a portion of the dust cover 5 that comes into contact with the ball stud 2.