JPH0745890B2 - Bush assembly - Google Patents

Description

TECHNICAL FIELD The present invention relates to a bush assembly used for mounting a suspension arm and the like.

(Prior Art) A bush assembly of this type has hitherto been disclosed in JP-A-61-127934.
As described in Japanese Patent Laid-Open Publication No. 2004-242242, an inner cylinder and an outer cylinder surrounding the inner cylinder are provided, and a support cylinder is inserted between the inner and outer cylinders to form an annular elastic body between the support cylinder and the outer cylinder, and a support cylinder. There is known a type in which a sliding member for reducing the torsion spring action of the annular elastic body due to the relative rotation of the inner and outer cylinders is filled between the inner cylinder and the inner cylinder.

In such a bush assembly, when water or the like enters around the sliding member, the sliding member and the inner cylinder are corroded to prevent the sliding between the two and impair the original function.

Therefore, it is necessary to provide a seal for preventing the invasion of water and the like, but in the case of this seal, conventionally, as shown in the above-mentioned document, outer flanges are provided upright on both end edges of the inner cylinder, and the support cylinder surrounds them. It was usual to make both ends of each of them have a large diameter and to fill the seal rubber between the outer circumference of each outer flange and the inner circumference of the large diameter end of the support cylinder.

(Problems to be Solved by the Invention) However, in such a seal structure, the seal rubber is located on the outer peripheral side of the outer flange of the inner cylinder to have a large diameter, and the circumferential frictional resistance between the seal rubber and the inner cylinder increases. For this reason,
Under the use condition in which the relative rotation of the inner and outer cylinders becomes large, the movability of the Sunpension arm or the like attached by the bush assembly is adversely affected, and the durability of the bush assembly is significantly impaired.

In addition, if water or the like intrudes between the seal rubber and the outer peripheral surface of the flange due to a defective seal, it is no longer possible to prevent this water or the like from reaching the periphery of the sliding member, and the reliability is low, and flying stones, etc. Foreign matter is likely to directly collide with the seal rubber, and a situation in which sealing is impossible due to external damage is likely to occur.

The present invention seeks to provide an improved bushing assembly which overcomes all of these problems.

(Means for Solving the Problem) For this purpose, a bush assembly according to the first invention comprises an inner cylinder and an outer cylinder surrounding the inner cylinder, and a support cylinder is inserted between the inner and outer cylinders to form a support cylinder. A bushing assembly in which an annular elastic body is filled between the outer cylinder and the outer cylinder, and a sliding member for reducing the torsion spring action of the annular elastic body due to the relative rotation of the inner and outer cylinders is filled between the support cylinder and the inner cylinder. In a three-dimensional space, flanges that extend outward in the radial direction are provided near both ends of the inner cylinder, and large-diameter ends that surround the flange with a gap therebetween are formed at both ends of the support cylinder. Then, a sealing metal fitting is fitted in these large-diameter ends, and the remaining portion of the sealing metal fitting other than the fitting portion is extended radially inward along the outer surfaces of the flanges that are far from each other. Attach the seal lip that contacts the outer surface of the flange to the extension. It is an butterfly.

A bush assembly according to a second aspect of the present invention includes an inner cylinder and an outer cylinder surrounding the inner cylinder. A support cylinder is inserted into the inner and outer cylinders to form an annular elastic body between the support cylinder and the outer cylinder. In a bush assembly in which a sliding member for reducing the torsion spring action of the annular elastic body due to the relative rotation of the inner and outer cylinders is filled between the support cylinder and the inner cylinder, respectively, in a radial direction near both ends of the inner cylinder. A flange extending outward is provided, and large-diameter ends that surround the flange with a gap therebetween are formed at both ends of the support cylinder, and sealing metal fittings are fitted in these large-diameter ends. At the same time, the remaining portion of the seal fitting other than the fitting portion is made to extend radially inward along the outer surfaces of the both flanges that are distant from each other, and then axially extended along the outer peripheral surface of the corresponding end portion of the inner cylinder. , The outer periphery of the flange and the outer periphery of the corresponding end of the inner cylinder are extended to the seal fitting. Of, is characterized in that it has secured the sealing lip in contact with the corresponding end portion outer peripheral surface of at least the inner cylinder.

(Operation) When an external force is applied in the radial direction between the inner and outer cylinders, the annular elastic body is correspondingly compressed and deformed in the radial direction to perform a buffering action. On the other hand, when an external force that relatively rotates the inner and outer cylinders acts, the annular elastic body elastically deforms in the circumferential direction to perform a buffering action, but at this time, the sliding member has a certain sliding resistance on the inner cylinder. Since it rotates, the elastic deformation of the annular elastic body is reduced, durability is ensured, and the hardness of the elastic body can be made appropriate.

The water, etc. that is fogged during practical use is prevented from invading the periphery of the sliding member by the seal fitting and the seal lip, and the situation in which the sliding member and the inner cylinder are corroded and the sliding between them is obstructed is avoided. obtain.

By the way, in the first aspect of the present invention, flanges that project outward in the radial direction are provided near both ends of the inner cylinder, and the flanges are surrounded by both ends of the support cylinder between the inner and outer cylinders with a gap therebetween. Large-diameter ends are formed, and seal fittings are fitted in the large-diameter ends, and the remaining portions of the seal fittings other than the fitting portions extend radially inward along the outer surfaces of the flanges that are far from each other. The seal structure has the seal lip fixed to the extension of the seal fitting in contact with the outer surface of the flange. Further, in the second invention, flanges are provided near the both ends of the inner cylinder so as to project outward in the radial direction. Forming large-diameter ends at both ends of the support cylinder between the inner and outer cylinders so as to surround the flange with a gap between them, and fitting a seal fitting into the large-diameter ends and The rest of the seal fittings other than After extending inward in the radial direction along the outer surfaces of the flange that are distant from each other, they are extended in the axial direction along the outer peripheral surface of the corresponding end portion of the inner cylinder. Among the outer peripheral surfaces of the corresponding end portions of the cylinder, at least the seal lip that is in contact with the outer peripheral surface of the corresponding end portion of the inner cylinder is fixed, so that the above-mentioned seal for preventing water and the like from entering around the sliding member. The lip is located radially inward of the outer circumference of the inner cylinder flange and has a small diameter, so that the friction resistance between the lip and the inner cylinder can be reduced. Therefore, it is possible to prevent the movement performance of the suspension arm or the like attached by the bush assembly from being adversely affected and the durability of the bush assembly from being impaired.

In addition, even if water or the like passes through the seal lip due to a defective seal, the water or the like does not reach the periphery of the sliding member unless it gets over the inner cylinder flange. The reliability of corrosion resistance can be improved. Further, the reduction in diameter of the seal lip is covered by the mounting bracket, so that it is possible to prevent the situation where the seal lip is damaged by flying stones and cannot be sealed.

(Example) Hereinafter, the Example of this invention is described in detail based on drawing.

FIG. 1 shows an embodiment of the bush assembly of the present invention. The bush assembly is concentrically provided with an inner cylinder 1 and an outer cylinder 2 surrounding the inner cylinder 1. The inner cylinder 1 has terminal collars at both ends of an inner cylinder body 3. 4 and 5 are fitted to each other, and the ring plates 6 and 7 are sandwiched between the fitting portions to set inner cylinder flanges extending radially outward near both ends of the inner cylinder 1.

A support cylinder 8 is inserted between the inner and outer cylinders 1 and 2, and an annular elastic body 9 is filled between the support cylinder 8 and the outer cylinder 2 to integrate these three members. Both ends of the support tube 8 are expanded to form large-diameter ends 8a and 8b,
These large diameter ends are designed to surround the flanges 6 and 7 with a gap.

The sliding members 10 and 11 are filled between the support cylinder 8 and the inner cylinder 1,
These are set as one pair and fitted from both ends of the support cylinder 8.
The sliding members 10 and 11 are integrally provided with flanges 6 and 7 and flange portions 10a and 11a sandwiched between the support cylinder large diameter ends 8a and 8b.

The metal fittings 12 and 13 are press-fitted into the large diameter ends 8a and 8b of the support cylinder,
These seal fittings are extended radially inward along the flanges 6 and 7 on the side far from the sliding members 10 and 11, and the seal fitting 1
Seal lips 14 and 15 contacting the outer peripheral surfaces of the terminal collars 4 and 5 are fixed in the extended ends 12a and 13a of the terminals 2 and 13.

In practical use of such a bush assembly, sliding members are provided in both ends of the support cylinder 8 integrated with the outer cylinder 2 and the annular elastic body 9.
10 and 11 are fitted together, and then the inner cylinder body 3 is inserted into the sliding members 10 and 11. Next, the terminal collars 4 and 5 are fitted into both ends of the inner cylinder main body 3 with the ring plates 6 and 7 applied to both end surfaces of the inner cylinder main body 3, and sealing metal fittings are provided in the support cylinder large diameter end 8a. 12,13
Press fit.

In this state, a collar such as a suspension arm that should be supported by the bush assembly is fitted to the outer circumference of the outer cylinder 2, and the bolts 17 are attached to the bracket 16 while sliding the terminal collars 4 and 5 between both legs of the mounting bracket 16. By inserting the bush assembly into the inner cylinder 2, the bush assembly is ready for practical use.

During this practical use, the seal lips 14 and 15 are filled with water from the outside 1
Prevents intrusion into the inside of 8, 19 and thus around the sliding members 10, 11. In addition, due to defective seal lips 14 and 15, space 1
Even if water or the like enters the inside of 8,19, the water or the like cannot reach the sliding members 10,11 unless they get over the flanges 6,7. For this reason, it is possible to prevent the sliding members 10 and 11 and the inner cylinder 1 from being corroded and prevent the original sliding between them from being hindered by this corrosion.

On the other hand, since the seal lips 14 and 15 are located inside the outer peripheries of the inner cylinder flanges 6 and 7, the diameter is small, and the frictional resistance with the inner cylinder 1 can be reduced. Therefore, it is possible to prevent the movement performance of the suspension arm or the like attached to the outer circumference of the outer cylinder 2 from being adversely affected and the durability of the bush assembly from being impaired. Further, the reduction in the diameter of the seal lips 14 and 15 means that the seal lips 14 and 15 are covered with the bracket 16, so that the seal lips 14 and 15 can be prevented from being damaged by the collision of flying stones or the like.

FIG. 2 shows another example of the bush assembly of the present invention. In this example, the inner cylinder 1 is divided into two inner cylinder portions 20 and 21, which are provided in a coaxial butting relationship. The inner cylinder flanges 6 and 7 are integrally formed at the corresponding positions of the inner cylinder portions 20 and 21, respectively. Similarly, the support tube portion 8 and the annular elastic body 9 are also divided into two divided portions 22, 23 and 24, 25, respectively.

Further, the seal fitting extensions 12a and 113a are provided with seal lips 26 and 27 which are in contact with the flanges 6 and 7, and seal lips 14 and 15 and
A double seal is made up of 26 and 27 to achieve complete sealing. That is, the seal lips 14 and 15 do not lose their sealing function even when the seal fittings 12 and 13 are displaced relative to the inner cylinder 1 in the axial direction, and the seal lips 26 and 27 have the seal fittings 12 and 13 relative to the inner cylinder 1. The sealing function is not lost even when the relative displacement is made in the radial direction. The seal lips 14, 15, 26, 27 can prevent the inner cylinder portions 20, 21 from coming off due to friction during the assembly work of the bush assembly, and can improve the assembly workability.

FIG. 3 shows still another example of the present invention, which is a seal fitting.
Only the axial seal lip 26 (27) contacting the inside of the flange 6 (7) is used as the seal lip fixed to the 12 (13), and in this case as well, the same operational effects as the above-mentioned respective embodiments can be obtained.

(Effect of the invention) Thus, the bush assembly according to the first invention is provided with the flanges 6 and 7 that project outward in the radial direction, respectively, near both ends of the inner cylinder 1,
Large-diameter ends 8a, which surround the flanges 6 and 7 with a gap between them, at both ends of the support cylinder 8 between the inner and outer cylinders 1 and 2, respectively.
8b is formed, and the seal fittings 12 and 13 are fitted in the large-diameter ends 8a and 8b, and the remaining portion of the seal fittings other than the fitting portion is arranged along the outer surfaces of the flanges 6 and 7 that are far from each other. The bushing assembly according to the second aspect of the present invention has an inner cylinder because it has a seal structure in which the seal lips 26 and 27 that contact the outer surfaces of the flanges 6 and 7 are fixed to the extension of the seal fittings. 1. Flanges 6 and 7 projecting outward in the radial direction are provided near both ends of 1, respectively, and the above-mentioned flanges are provided at both ends of the support cylinder 8 between the inner and outer cylinders 1 and 2, respectively.
Large-diameter ends 8a and 8b are formed so as to surround 6, 7 with a gap therebetween, and seal fittings 12 and 13 are fitted in the large-diameter ends 8a and 8b, and other than the fitting portion. After the remaining portion of the seal fitting is extended inward in the radial direction along the outer surfaces of the flanges 6 and 7 that are far from each other, the seal is extended in the axial direction along the outer peripheral surface of the corresponding end portion of the inner cylinder 1. A seal structure in which seal lips 14 and 15 that are in contact with at least the corresponding outer peripheral surfaces of the inner cylinder 1 among the outer surfaces of the flanges 6 and 7 and the corresponding outer peripheral surfaces of the inner cylinder 1 are fixed to the extended portion of the metal fitting Therefore, the above seal lips 14, 15, 26, 27 for preventing water and the like from entering the periphery of the sliding members 10, 11 are provided with the inner cylinder flanges 6, 7
The diameter of the inner cylinder 1 is smaller than that of the outer periphery of the inner cylinder 1, and the frictional resistance with the inner cylinder 1 can be reduced. Therefore, it is possible to prevent the movement performance of the suspension arm or the like attached by the bush assembly from being adversely affected and the durability of the bush assembly from being impaired.

In addition, in the unlikely event of a defective seal, seal lips 14, 15 (2
Even if there is water or the like that has passed through 6,27), the water or the like does not reach the sliding members 10 and 11 unless it gets over the flanges 6 and 7, and the reliability of the seal can be improved. further,
The reduction in the diameter of the seal lip covers it with the mounting bracket 16 and protects it from flying stones and the like, so that a seal defect due to external damage to the seal lip can be eliminated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example configuration of the bush assembly of the present invention, FIG. 2 is a cross-sectional view similar to FIG. 1 showing another example of the present invention, and FIG. 3 is still another example of the present invention. It is a principal part sectional view shown. 1 …… inner cylinder, 2 …… outer cylinder 6,7 …… flange, 8 …… support cylinder 9 …… annular elastic body, 10,11 …… sliding member 12,13 …… seal fitting 12a, 13a …… Seal metal fitting extension 14,15,26,27 …… Seal lip

Claims (2)

[Claims] 1. An inner cylinder and an outer cylinder surrounding the inner cylinder. A support cylinder is inserted between the inner and outer cylinders to form an annular elastic body between the support cylinder and the outer cylinder, and between the support cylinder and the inner cylinder. In a bush assembly in which sliding members for reducing the torsion spring action of the annular elastic body due to the relative rotation of the inner and outer cylinders are respectively filled between the cylinder and the cylinder, the bush assemblies are radially extended near both ends of the inner cylinder. Providing flanges, large-diameter ends are formed at both ends of the support cylinder so as to surround the flanges with a gap therebetween, and seal fittings are fitted into the large-diameter ends and The remaining portion of the seal fitting other than the attachment portion extends inward in the radial direction along the outer surfaces of the flanges that are far from each other, and a seal lip that is in contact with the outer surface of the flange is fixed to the extension portion of the seal fitting. Bush assembly. 2. An inner cylinder and an outer cylinder surrounding the inner cylinder. A support cylinder is interposed between the inner cylinder and the outer cylinder to form an annular elastic body between the support cylinder and the outer cylinder, and between the support cylinder and the inner cylinder. In a bush assembly in which sliding members for reducing the torsion spring action of the annular elastic body due to the relative rotation of the inner and outer cylinders are respectively filled between the cylinder and the cylinder, the bush assemblies are radially extended near both ends of the inner cylinder. Providing flanges, large-diameter ends are formed at both ends of the support cylinder so as to surround the flanges with a gap therebetween, and seal fittings are fitted into the large-diameter ends and The remaining portion of the seal fitting other than the fitting portion extends radially inward along the outer surfaces of the flanges that are far from each other, and then extends in the axial direction along the outer peripheral surface of the corresponding end portion of the inner cylinder. Of the outer surface of the flange and the outer peripheral surface of the corresponding end portion of the inner cylinder, at least the inner cylinder A bush assembly having a seal lip fixed to the outer peripheral surface of the corresponding end of the above.