JP2529036Y2 - Dust cover - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention relates to a dust cover used for sealing a ball joint portion of a steering device of an automobile, for example.

(Prior Art) FIG. 4 shows a dust cover 100 for a ball joint of a conventional automobile steering apparatus. A dust cover 100 made of a rubber-like elastic body has an annular first mounting portion 102 mounted on a stud 101 as one of two members assembled so as to be relatively movable, and a socket as the other member. It has an annular second mounting portion 104 mounted on the 103, and a flexible film portion (tubular portion) 105 connecting the first and second mounting portions 102, 104. Further, metal rings 106 and 107 integrated by vulcanization molding are embedded in the first and second mounting portions 102 and 104. Further, the stud 101 includes a shaft portion 108 and a ball portion 109, and the upper end side of the shaft portion 108 is connected to a knuckle arm (not shown).

In the above configuration, when the stud 101 moves relative to the socket 103 as shown by an arrow, that is, swings with the ball 109 as a fulcrum, the film portion 105 bends to ensure the followability. Then, the sliding surface between the socket 103 and the ball portion 109 is lubricated by grease (not shown) sealed in the dust cover 100.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional example, the film portion 105 is thinner than a predetermined thickness in order to ensure followability. For this reason, a stepping stone may collide with the membrane portion 105 while the vehicle is running, or a sharp portion of ice on a substantially surface in a cold region may be pierced, causing cracks and breakage, resulting in reduced sealing performance. . Therefore, in order to increase the strength of the film portion 105, it is possible to increase the wall thickness so as to absorb impacts such as flying stones.

This invention is intended to solve the above-mentioned problem, and an object of the invention is to provide a dust cover which can prevent cracking and breakage of a cylindrical portion without impairing the ability to follow relative movement of two members.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a stud mounting portion mounted on a stud, a socket mounting portion mounted on a socket to which the stud is relatively movably connected,
In a dust cover having a flexible film portion connecting the stud mounting portion and the socket mounting portion, a protective sheet for reinforcement covering from the socket mounting portion to the film portion is integrally provided.

(Operation) In the present invention, the protective sheet is provided integrally so as to cover from the socket mounting portion to the film portion, and is not provided on the stud mounting portion, so that the space between the stud mounting portion and the film portion is freely deformed. As a result, followability to the movement of the stud can be secured. On the other hand, since the protective sheet covers from the socket mounting portion to the film portion, the film portion can be protected from stepping stones and ice in cold regions.

(Example) Next, the Example of this invention is described based on drawing.

FIGS. 1 and 2 show a dust cover 1 for a ball joint of an automobile steering system according to a first embodiment.
That is, an annular first attachment portion 3 as a stud attachment portion attached to the stud (one member) 2, an annular second attachment portion 5 as a socket attachment portion attached to the socket (the other member) 4, It is made of a rubber-like elastic body having a flexible membrane (cylindrical portion) 6 to which the first and second mounting portions 3, 5 are connected. 7, 8 are integrally embedded by vulcanization molding.

A canvas (thin plain woven fabric) 9 as a protective sheet is embedded in the outer periphery (surface) of the film portion 6. The canvas 9 is designed to protect the vicinity of the upper end of the socket 4 where cracks are most likely to occur due to stepping stones or the like from the ground.
The upper end is located substantially at the center of the film portion 6 in the height direction, and the lower end is sandwiched between the bent portions of the metal ring 8. The reason why the lower end of the canvas 9 is sandwiched between the metal rings 8 is as follows.
This is because the workability of placing in the cavity during vulcanization molding is improved by integrating the components in advance. The canvas 9 is provided over the entire periphery of the film section 6 as shown in FIG.

The stud 2 includes a shaft portion 10 and a ball portion 11, and the shaft portion 10 is connected to a knuckle arm (not shown).

 Next, the operation of the above embodiment will be described.

When the stud 2 moves relative to the socket 4 as shown by an arrow, that is, swings around the ball 11 as a fulcrum, the ball 11
The sliding surface between the socket 4 and the socket 4 is lubricated by grease (not shown) sealed in the dust cover 1, and the followability is ensured by bending the film portion 6. Here, canvas 9
Is flexed integrally with the film portion 6 and does not affect the followability.

On the other hand, while the vehicle is running, even if the stones flipped by the wheels fly toward the dust cover 1 or there is sharp ice on the road surface in a cold region, the stones and ice come into contact with the canvas 9. Since the film 6 does not come into contact with the film 6, the film 6 can be prevented from being cracked or damaged, and the sealing performance of the dust cover 1 can be ensured.

 FIG. 3 shows a second embodiment.

In the second embodiment, the upper end of the canvas 9 is located near the first mounting portion 3 in the height direction. With this configuration, even if a small crack is formed downward from a portion where the canvas 9 is not embedded, the progress of the crack in the circumferential direction of the film portion 6 is prevented by the presence of the canvas 9. Thus, the durability is further improved. Other configurations, operations, and effects are the same as those in the first embodiment, and thus description thereof is omitted.

In this embodiment, the case where the present invention is applied to a dust cover for a ball joint of a steering apparatus of an automobile has been described. However, the present invention can also be applied to a construction machine, a cultivator, and the like. Further, the shape of the dust cover itself is not limited to the illustrated one, and can be applied to various shapes.

(Effects of the Invention) Since the invention is configured as described above, the protection sheet is provided integrally from the socket mounting portion to the film portion, and is not provided on the stud mounting portion. The space between the parts can be freely deformed to ensure the followability to the movement of the stud. On the other hand, since the portion from the socket mounting portion to the film portion is covered with the protective sheet, the film portion can be protected from stepping stones and ice in a cold region, and an excellent sealing property can be ensured.

[Brief description of the drawings]

FIG. 1 is a front half sectional view showing a first embodiment in which the present invention is applied to a dust cover for a ball joint, and FIG.
FIG. 3 is a front cross-sectional view of the dust cover taken along the line AA of FIG. 3, FIG. 3 is a front half cross-sectional view of the second embodiment, and FIG. DESCRIPTION OF SYMBOLS 1 ... Dust cover 2 ... Stud (one member) 3 ... First mounting part 4 ... Socket (the other member) 5 ... Second mounting part 6, 6 ... Film part (cylindrical part) 7,8 Metal ring 9 Canvas (protective sheet) 10 Shaft, 11 Ball

Claims (1)

(57) [Scope of request for utility model registration] A stud mounting portion mounted on the stud;
In a dust cover having a socket mounting portion to be mounted on a socket to which the stud is relatively movably connected, and a flexible film portion connecting between the stud mounting portion and the socket mounting portion, A dust cover, wherein a protective sheet for reinforcement covering the film portion is provided integrally.