JPH0552443U - Dust cover - Google Patents

Abstract

(57) [Summary] (Corrected) [Construction] Dust cover 2 is made of urethane, and a reinforcing ring is formed in advance on the dust cover and fitted into a circumferential mounting groove that does not communicate the inside and outside of the dust cover. cover. [Effect] Even if water or the like tries to enter the inside of the dust cover from the outside, the holes that connect the inside and outside of the dust cover are not formed, so the water does not enter and the durability of the product with the dust cover is improved. ..

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a dust cover of a joint member used in, for example, a suspension system and a steering system of an automobile, and more particularly to a dust cover in which a reinforcing ring is installed in an opening.

[0002]

[Prior Art]

 Conventionally, as shown in the left half of FIG. 1, as a dust cover in which an annular reinforcing ring 114 that reinforces the pressure contact force to a mating member is embedded in a cylindrical opening 103 with both ends open, it is actually used. Many are known, such as those disclosed in Japanese Utility Model Publication No. 62-149616, Japanese Utility Model Publication No. 2-36973, and Japanese Utility Model Publication No. 3-19612.

[0003]

[Problems to be solved by the device]

 The dust cover 102 as described above is often molded from synthetic rubber which is generally high in elasticity and inexpensive. The manufacturing process of the dust cover 102 made of synthetic rubber will be described with reference to FIG. 5. Reference numeral 151 is an upper mold of a mold 150 which is divided into upper and lower halves, and a plurality of reinforcements are provided from a lower end surface 153 of the upper mold 151. The upper fixing members 152 for fixing the ring 114 project at equal intervals. Further, 161 is a lower mold of a mold 150 which is divided into upper and lower halves, and a plurality of lower fixing members 162 for fixing the reinforcing rings 114 project from the upper end surface 163 of the lower mold 161 at equal intervals. In this mold 150, a reinforcing ring 114 having an adhesive applied on its surface is placed on the lower fixture 162 of the lower mold 161 in a state where the upper mold 151 is preliminarily positioned above, and the upper mold is continuously raised. As shown in FIG. 5A, the mold 151 is lowered to close the mold 150 to form a mold engraving space 156 and to fix the reinforcing ring 114 in the mold 150. Next, as shown in FIG. 5A, synthetic rubber is injected into the mold engraving space 156 in the mold 150, and after a certain period of time, the upper mold 151 is lifted and the dust cover 102 is moved to the lower mold 161. After further separating, the dust cover 102 as shown in FIG. 5C and FIG. 4 is formed.

However, when the dust cover 102 made of synthetic rubber is used for a long period of time with a product equipped with the dust cover 102, for example, a ball joint 101 as shown in the left half of FIG. 1, ozone contained in the air is included. There is a problem in that the dust cover 102 is cracked due to deterioration due to the above. In particular, the opening 103 has an upper hole 154 and a lower hole 164 formed by an upper fixing member 152 and a lower fixing member 162 for fixing the reinforcing ring 114 when the dust cover 102 is molded, and the upper hole 154 and the lower hole 164 are Cracks are likely to occur along.

Therefore, in recent years, a urethane dust cover may be used together with the synthetic rubber. This urethane is a general term for rubber-like elastic materials obtained by the reaction of polyester or polyether and isocyanate, and generally has excellent wear resistance and resistance to ozone deterioration, and is used in almost all fields of rubber industrial products. Has a wide range of uses. By forming the dust cover with this urethane, it becomes possible to improve durability as compared with the dust cover made of synthetic rubber. Further, the deformation resistance when the dust cover is deformed is extremely low, which is effective for reducing the operating torque of the ball stud of the ball joint, for example.

However, when a urethane dust cover is injection-molded in the same manner as the synthetic rubber dust cover as described above, the adhesive force between the reinforcing ring having the adhesive applied to the surface and the urethane material is low. As shown in, the reinforcing ring 214 is peeled off from the urethane material, and a gap 271 is generated therebetween. Therefore, in the assembled ball joint, when water or the like enters from between the lip 206 of the dust cover 202 and the connecting rod, the water passes from the upper hole 254 of the dust cover 202 through the gap 271 and the lower hole 264 of the ball joint. There is a problem that iron-based members such as ball studs get rusted inside and the durability of the ball joint is reduced.

An object of the present invention is to solve the above problems and to provide a dust cover which is less deteriorated even when it is used for a long period of time and which prevents intrusion of water and the like.

[0008]

[Means for Solving the Problems]

 The present invention has the following configuration.

The dust cover is made of urethane, and a reinforcing ring is fitted into a circumferential mounting groove that is formed in the dust cover and does not communicate with the inside and outside of the dust cover.

[0010]

【Example】

 The configuration of the embodiment of the present invention will be described below with reference to FIGS.

FIG. 2 shows a urethane dust cover 2 according to an embodiment of the present invention. In the figure, the dust cover 2 has a cylindrical shape with both ends open, and one end is a large-diameter opening 4 and the other end is a small-diameter opening 3. A reinforcing ring 14 is installed inside the opening 3, and a lip 6 is formed on the outer peripheral surface.

The right half of FIG. 1 shows a ball joint 1 equipped with a dust cover 2 according to an embodiment of the present invention. In the figure, 8 is a ball stud composed of a handle portion 9 and a ball head 10, and 11 is a bearing made of synthetic resin, which encloses the ball head 10 of the ball stud 8 so as to be swingable and rotatable. Reference numeral 12 denotes a housing, which contains a bearing 11 that encloses the ball head 10 of the ball stud 8 and has an opening 13 through which the handle 9 of the ball stud 8 projects. An inner peripheral shoulder portion 15 for seating the retaining ring 5 for preventing the ball stud 8 from coming off is formed on the inner periphery of the end portion of the housing 12 on the opening 13 side, and a peripheral flange portion 17 is formed on the outer periphery. A peripheral cover mounting portion 16 is formed adjacent to the flange portion 17.

The dust cover 2 has an opening 3 at one end on the small diameter side mounted on the outer periphery of the handle 9 of the ball stud 8, and an opening 4 on the other end at the large diameter side mounted in the cover mounting portion 16 of the housing 12. It is pressed and fixed to the housing 12 by the circlip 7. The lip 6 formed on the outer peripheral surface of the opening 3 of the dust cover 2 seals between the shank 9 of the ball stud 8 and the connecting rod 18 fitted therein.

Next, a method of manufacturing the dust cover of the present invention will be described with reference to FIG.

In the figure, reference numeral 50 designates a mold which is divided into upper and lower halves and is composed of an upper mold 51 and a lower mold 61. .. From the upper end surface 63 of the lower mold 61, a lower fixture 62 having the same shape is circumferentially projected at the same position as the reinforcing ring 14 of the dust cover 2. In the lower fixture 62, the radial width of the tip portion 62a, which is the end portion, is formed to be wider than the radial width of the root portion 62b near the upper end surface 63 of the lower die 61.

When molding the dust cover 2 using the mold 50, first, the upper mold 51 is lowered to close the mold 50 as shown in FIG. Next, as shown in (a) of FIG. 3, the urethane heated to about 80 degrees is projected into the mold engraving space 56 of the mold 50, and the upper mold 51 is lifted after a lapse of a certain time, for example, about 1 minute. At the same time, the dust cover 2 is forcibly removed from the lower mold 61, and as shown in FIG. 3C, the dust cover 2 has a circumferential mounting groove 19 on the inner peripheral side near the opening 3 of the dust cover 2. ′ Is molded. Finally, the annular reinforcing ring 14 is fitted into the mounting groove 19 to manufacture the dust cover 2 as shown in FIG. Here, the tip end portion 62a of the lower fixture 62 is formed to be slightly wider in the radial direction than the root portion 62b in order to prevent separation after the dust cover 2 is fitted.

In the ball joint 1 using such a dust cover 2, even if water or the like enters from between the lip 6 of the dust cover 2 and the connecting rod 18, the upper and lower holes are formed in the dust cover 2. Since it has not been formed, no more water will enter.

[0018]

[Effect of the device]

 As described above, according to the present invention, since the dust cover is made of urethane and the reinforcing ring is fitted into the circumferential mounting groove which is formed in advance on the dust cover and does not communicate the inside and the outside of the dust cover, it is possible to prevent water from the outside. When the dust cover and the like try to enter the inside of the dust cover, the holes that connect the inside and the outside of the dust cover are not formed, so that water and the like do not enter and the durability of the product equipped with the dust cover is improved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional plan view showing a ball joint equipped with a conventional dust cover in a left half portion and a right half portion in which a dust cover is mounted according to an embodiment of the present invention.

FIG. 2 is a sectional plan view showing a dust cover according to an embodiment of the present invention.

FIG. 3 is a cross-sectional plan view showing a process of manufacturing a dust cover according to an embodiment of the present invention.

FIG. 4 is a sectional plan view showing a conventional dust cover.

FIG. 5 is a cross-sectional plan view showing a process of manufacturing a conventional dust cover.

FIG. 6 is a cross-sectional plan view showing another embodiment of the conventional dust cover.

[Explanation of symbols]

 2 Dust cover 3 Opening 14 Reinforcing ring 19 Mounting groove

Claims (1)

[Scope of utility model registration request] 1. A dust cover in which an annular reinforcing ring (14) for reinforcing the pressure contact force to a mating member is installed in at least one opening (3) of the substantially cylindrical shape having both ends open, The dust cover (2) is made of urethane, and the reinforcing ring (14) is further formed in the circumferential mounting groove (19) which is preformed on the dust cover (2) and does not communicate the inside and outside of the dust cover (2). Dust cover characterized by being fitted.