JPH0710543U - Dust cover for ball joint - Google Patents

Abstract

(57) [Abstract] [Purpose] A dust cover for a ball joint in which a seal portion 3 to be fitted to a ball stud 12 is provided at one end of the membrane portion 1 and a dust seal 4 for contacting the knuckle arm 13 is provided in the seal portion 3. With respect to the above, it is prevented that the dust seal 4 is pulled by the film portion 1 when the ball stud 12 swings and is separated from the knuckle arm 13 at a part of the circumference, and the sealing performance is deteriorated. Further, the wear due to the sliding of the dust seal 4 is reduced. [Structure] A first notch 5 is provided on the outer peripheral surface of the seal portion 3,
Even if the ball stud 12 swings and a tensile force F is generated on the extension side of the film portion 1, the tensile force F is prevented from directly acting on the dust seal 4. Further, the second notch 6 is provided in the vicinity of the base end of the dust seal 4 so that the contact of the dust seal 4 with the knuckle arm 13 is weak.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement in a dust cover for a ball joint. The ball joint equipped with the dust cover of the present invention is widely used in automobiles or industrial machines.

[0002]

[Prior art]

 Conventionally, as shown in FIG. 4, a membrane part 1 having a substantially lantern shape is provided, and a fitting part 2 to be fitted to the outer periphery of a socket 11 of a ball joint is provided at the lower end of the film part 1 and the membrane part 1 is provided. A seal portion 3 slidably fitted to the outer periphery of the ball stud 12 is provided at the upper end of the portion 1, and a dust seal 4 that comes into sliding contact with the lower surface of the knuckle arm 13 is provided on the outer peripheral edge of the upper end of the seal portion 3. A provided dust cover for a ball joint is known (see, for example, Japanese Patent Laid-Open No. 3-89016). The film portion 1 is formed of a rubber-like elastic material, and thus has the flexibility of being freely deformed as the ball stud 12 swings. The seal portion 3 slidably comes in close contact with the outer peripheral surface of the ball stud 12, and seals the grease enclosed in the dust cover so as not to leak outside. The dust seal 4 slidably contacts the lower surface of the knuckle arm 13 and seals them so that external dust or water does not enter the inside of the dust cover.

[0003]

[Problems to be solved by the device]

 However, in the above-mentioned conventional dust cover, as shown in FIG. 5, when the ball stud 12 swings largely and a large pulling force F is generated on the extension side of the film portion 1, the dust seal 4 causes the film portion 1 to move. It may be pulled away by the knuckle arm 13 at a part of the circumference, and external dust or water may enter the inside of the dust seal 4 and adversely affect the sliding of the seal portion 3 and the ball stud 12. There is. Further, since the dust seal 4 originally has high rigidity, the contact (contact strength) of the dust seal 4 with the knuckle arm 13 is too strong, and there is a problem that the dust seal 4 is greatly worn due to sliding.

[0004]

[Means for Solving the Problems]

 In view of the above points, the present invention has been devised to solve the above-mentioned problems in the prior art, and in order to achieve this object, a seal portion fitted to a ball stud is attached to one end of the membrane portion. In a dust cover for a ball joint in which a dust seal that comes into contact with a knuckle arm is provided in the seal portion, a first notch is provided on the outer peripheral surface of the seal portion, and a second notch is provided near the base end of the dust seal. It was to be .

[0005]

[Action]

 If a notch (first notch) is provided on the outer peripheral surface of the seal part, the tensile force generated on the stretch side of the membrane part does not directly act on the dust seal, and thus prevents the dust seal from separating from the knuckle arm. You can Further, if the notch (second notch) is provided near the base end of the dust seal, the contact of the dust seal with the knuckle arm becomes weaker than in the past.

[0006]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the dust cover for a ball joint has a substantially lantern-shaped membrane portion 1 at the lower end of the membrane portion 1. The fitting portion 2 fitted to the outer periphery of the socket 11 is provided, and the seal portion 3 slidably fitted to the outer periphery of the ball stud 12 is provided at the upper end of the film portion 1, and the upper end of the seal portion 3 is provided. A dust seal 4 which slidably contacts the lower surface of the knuckle arm 13 is provided on the outer peripheral edge, and further has the following configuration.

That is, as shown in an enlarged manner in FIG. 2, a first notch 5 having an annular shape is provided on the outer peripheral surface of the seal portion 3, and a base end of the dust seal 4 is provided above the first notch 5. The second notch 6 is provided in the vicinity. The widths a and the depths b of the first notches are 0.5 to 3.0 mm in actual size, respectively, and are appropriately determined according to the volume of the dust seal 4.

In the dust cover having the above structure, since the ring-shaped first notch 5 is provided on the outer peripheral surface of the seal portion 3, as shown in FIG. Even if the tensile force F is generated on the extension side of the portion 1, the tensile force F does not directly act on the dust seal 4. Therefore, the dust seal 4 can be prevented from being pulled by the membrane portion 1 and separated from the knuckle arm 13 at a part of the circumference, and external dust or water can be prevented from entering the inside of the dust seal 4. be able to. Further, since the second notch 6 having an annular shape is provided in the vicinity of the base end of the dust seal 4, the contact of the dust seal 4 with the knuckle arm 13 is weaker than before, and the wear caused by sliding of the dust seal 4 is reduced. It can be further reduced. This effect is considerably large because the first notch 5 is provided below the second notch 6 and the elastic force of the dust seal 4 is further weakened. Moreover, the first and second notches 5 and 6 do not necessarily have to be annular, and may be, for example, dotted lines along the circumference.

[0009]

[Effect of device]

 The present invention has the following effects. That is, even if a first notch is provided on the outer peripheral surface of the seal portion so that the ball stud oscillates and a tensile force is generated on the extension side of the film portion, this tensile force does not directly act on the dust seal. Therefore, it is possible to prevent the dust seal from being pulled by the membrane part and separating from the knuckle arm at a part of the circumference, and prevent outside dust or water from entering the inside of the dust seal. be able to. Therefore, the sealing performance of the dust seal is improved. Further, since the second notch is provided in the vicinity of the base end of the dust seal to make the contact of the dust seal with the knuckle arm weaker than before, it is possible to reduce the wear caused by sliding of the dust seal more than before. Therefore, the durability of the dust seal is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a mounted state of a ball joint dust cover according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part of the ball joint dust cover.

FIG. 3 is a sectional view showing an operating state of the ball joint dust cover.

FIG. 4 is a cross-sectional view showing a mounted state of a ball joint dust cover according to a conventional example.

FIG. 5 is a sectional view showing an operating state of the ball joint dust cover.

[Explanation of symbols]

 1 Membrane Part 2 Fitting Part 3 Seal Part 4 Dust Seal 5 First Notch 6 Second Notch 11 Socket 12 Ball Stud 13 Knuckle Arm

Claims (1)

[Scope of utility model registration request] 1. A ball stud (1) is provided at one end of the film portion (1).
In a dust cover for a ball joint, a seal part (3) fitted to the second part (2) is provided, and a dust seal (4) contacting the knuckle arm (13) is provided on the seal part (3). First notch (5) on the outer peripheral surface of
And a second notch (6) near the base end of the dust seal (4).