JPS62278331A - Bush assembly - Google Patents

Abstract

PURPOSE:To improve durability by inserting an elastic member between an inner tube member and an outer tube member, inserting a sliding member between the elastic member and the inner tube member, inserting a rigid sleeve member between the elastic member and the sliding member, and fitting a seal member with metal to its end section. CONSTITUTION:In this bush assembly suitable to be used at the pivotable connection section of the suspension of a vehicle, a cylindrical rubber block 14 is inserted between a cylindrical inner tube member 10 and an outer tube member 12 made of metal and located concentrically. A metal sleeve 16 with relatively high rigidity and a pair of oil-bearing polyacetal resin cylinders 18, 18 which are sliding members are inserted between the rubber block 14 and the inner tube member 12. A cylindrical extension section 42 is formed at the end section of the sleeve 16, and a stop ring 20 is press-fitted inside this extension section 42 and outside the end section of the inner member 10. A ring-shaped seal member 24 with metal is inserted between this stop ring 20 and the sleeve 16 for sealing.

Description

DETAILED DESCRIPTION OF THE INVENTION 3. Detailed Description of the Invention (Technical Field) The present invention relates to a bushing assembly, and more particularly to a bushing assembly suitable for use in a pivot joint of a vehicle suspension.

(Prior Art) A bushing assembly used in a pivot connection part of a vehicle suspension, for example, a control arm bushing used in a connection part between a control arm and a vehicle body side or axle side member, is as follows: -a. , a cylindrical elastic member made of a rubber material is interposed between two concentrically arranged inner and outer cylindrical members, and due to the spring characteristics of the elastic member, it is mainly perpendicular to its axis. It is designed to absorb vibrations in different directions. However, in such a bushing assembly, due to the spring action of the elastic member, if the rigidity in the direction perpendicular to the axis is increased, the torsional rigidity around the axis also increases.

Therefore, a sliding member (friction reducing means) is provided between the cylindrical member and the elastic member to reduce the torsional spring action by the elastic member.
For example, US Patent No. 333164
This method has been proposed in the specification of No. 2 and Japanese Utility Model Application Publication No. 59-153736. According to such a bushing assembly, since the frictional resistance between the cylindrical member and the elastic member is reduced by the sliding member, the cylindrical member and the elastic member are The elastic member can be rotated relative to the elastic member relatively easily around the axis, and therefore, the rigidity around the axis can be lowered while maintaining the rigidity in the direction perpendicular to the axis.

(Problems to be Solved by the Invention) However, in a bushing assembly including such a sliding member, solids such as soil and sand are present in the sliding part between the sliding member and the cylindrical member. When particles, muddy water, etc. enter, the sliding surfaces of these components become scratched, or rust occurs on the sliding surfaces of cylindrical members, which are usually made of metal materials, causing damage to the cylindrical members and their elasticity. Relative rotation (sliding) between the sliding member and the sliding member may be impaired, and as a result, there is a risk that the sliding member may not be able to fully exhibit its tear spring effect reduction effect.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned problems, and the gist of the invention is to solve the problems described above. In the bushing assembly, a predetermined elastic member is interposed in the bushing assembly, and a sliding member is interposed between the elastic member and the inner cylindrical member to reduce the tear spring action of the elastic member. further interposing a rigid sleeve member between the sliding member and the sliding member;
The end portion of the rigid sleeve member is constituted by an outer flange portion extending radially outward and a cylindrical extension portion extending axially outward from the outer periphery of the outer flange portion, while the outer periphery of the end portion of the inner cylindrical member A retaining ring for preventing the sliding member from coming off is press-fitted into the surface.

Furthermore, a ring-shaped sealing member with a fitting is interposed between the retaining ring and the cylindrical extension at the end of the rigid sleeve member to form a seal therebetween.

(Operation/Effect) In such a bushing assembly, there is a gap between the cylindrical extension at the end of the rigid sleeve member and the outer peripheral surface of the retaining ring member located at the end of the inner cylinder member. Sealed by the sealing member, soil, sand, etc.
Since the intrusion of muddy water etc. is effectively prevented,
The relative rotation between the sliding member interposed between the rigid sleeve member and the inner cylinder member and the rigid sleeve member and/or the inner cylinder member is not impaired, and therefore This allows the sliding member to fully exhibit its inherent effect of reducing the tear spring action.

Moreover, the sealing member with a fitting, which is usually press-fitted into the inner circumferential surface of the cylindrical extension of the rigid sleeve member and is brought into contact with the outer circumferential surface of the retaining ring member, is able to withstand loads input in the axial direction of the bushing, Since there is virtually no radial load acting between the inner and outer metal fittings, it is possible to minimize their wear and tear, thereby extending the life of the sealing member. , the sealing effect can be made permanent, and since there is no relative displacement in the radial direction between the rigid sleeve member and the retaining ring member, despite changes in the load applied in the radial direction,
A constant sealing effect can always be obtained.

In particular, according to the configuration of the present invention, since the elastic member of the bushing main body and the sealing member with a metal fitting of the sealing part are different, there is an advantage that the spring characteristics of the bushing can be freely selected. Durability is advantageously improved because there is no input load to the seal part, and since it uses a shaft seal structure that holds the seal member on the circumference of the shaft, play in the direction perpendicular to the shaft is effectively eliminated. It became possible to prevent or suppress it.

In addition, the sliding member is interposed between a rigid sleeve member and an inner cylinder member that have relatively high rigidity, and is protected by the rigid sleeve member and the inner cylinder member, so that it is protected from external forces. Deformation (inner diameter deformation) and cracking of the sliding member due to vibration loads and the like can be effectively prevented, thereby ensuring a good rotational resistance reduction effect and extending its life.

(Example) Next, in order to clarify the present invention more specifically, an example of the present invention will be described in detail based on the drawings.

First, FIG. 1 is a longitudinal cross-sectional view showing an example of a bushing assembly according to the present invention. In this figure, 10 is a cylindrical metal outer cylinder member, and a predetermined distance is provided on the innermost side of the outer cylinder member. A cylindrical metal inner cylinder member 12 is arranged concentrically. A cylindrical rubber block 14 as an elastic member is interposed between the outer cylinder member 10 and the inner cylinder member 12.
A relatively rigid metal sleeve 16 serving as a rigid sleeve member and a pair of oil-impregnated polyacetal resin cylinders 18 and 18 constituting sliding members are interposed between them. Annular retaining rings 20 and 20 are press-fitted and fixedly assembled into the outer periphery of both ends of the inner cylindrical member 12, and between the retaining rings 20, 20 and the ends of the sleeve 16. An annular metal fitting sealing member 24.24 is press-fitted and interposed therein.

Here, the outer cylinder member 10 is shown in FIGS. 2 and 3.
As shown, a small diameter section 28 and a large diameter section 30
It has a stepped cylindrical shape, and its large diameter part 3
At the end on the 0 side, an outer flange portion 3 extending radially outward is provided.
On the other hand, a tapered surface 34 is formed at the end on the small diameter part 28 side, and from the small diameter part 28 side, a predetermined mounting hole for a suspension control arm, etc. (not shown) is formed. It is press-fitted and fixed.

Further, as is clear from FIGS. 4 and 5, the sleeve 16 includes a cylindrical portion 36 having a smaller diameter and slightly longer axial length than the outer cylindrical member 10, and a cylindrical portion 36 from both ends of the cylindrical portion 36. radially outwardly extending outer flange portion 38.38
and a cylindrical extension 42.42 extending axially outward from the outer periphery of the outer flange portion 38.38.

The outer cylinder member 10 and the sleeve 16 are arranged concentrically, and the rubber block 14 is interposed between them. Such a rubber block 14 includes, for example, as shown in FIG. 6, an outer cylinder member 10 and a sleeve 16 are arranged concentrically, and a predetermined rubber material is vulcanized in an annular space formed between them. Preferably, it is formed by molding. In this way, the rubber block 14
At the same time as the rubber block 14 is formed, the outer cylinder member 10
The outer cylindrical member 1o, the sleeve 16, and the rubber block 14 are vulcanized and bonded to the inner peripheral surface of the sleeve 16 and the outer peripheral surface of the sleeve 16, thereby forming an integral structure. Thereafter, the outer cylinder member 10 of the vulcanized molded body as shown in FIG. is firmly fixed. In addition, during this vulcanization molding, the outer cylinder member 10 is arranged so as to be located outside the cylindrical part 36 of the sleeve 16, and the rubber block 14 is arranged between them and between the outer flange part 32 and one of the cylindrical parts. It will be formed between the extension portion 42 and the extension portion 42 .

Further, the sealing member 24 with an annular metal fitting is vulcanized and molded separately from the rubber block 14, and as shown in FIGS. A sealing rubber 46 is fixed to the surface in a ring shape. And, on the inner peripheral surface of this seal rubber 46,
One circumferential groove is provided and two lip portions 48 are provided.
．． 48 is formed to fully exhibit its sealing effect. As shown in FIG.
The sealing rubbers 46 and 46 are brought into contact with the outer circumferential surfaces of the retaining rings 20 press-fitted into the retaining rings 20, respectively, and are compressively deformed between the inner circumferential surfaces of these cylindrical extensions 42 and 42 and the outer circumferential surfaces of the retaining rings 20. It is now possible to

This creates an effective seal between the cylindrical extension 42, 42 and the retaining ring 20, preventing dirt, sand, muddy water, etc. from entering between the inner cylindrical member 12 and the cylindrical body 12. be done.

On the other hand, the cylindrical bodies 18, 18 constituting the sliding member each have a cylindrical shape having an outer diameter approximately the same as the inner diameter of the sleeve 16, as shown in FIGS. 9 and 10. An outer flange portion 50 extending radially outward is provided at one end thereof, and four axial grooves 52 are formed on the inner peripheral surface at equal angular intervals in the circumferential direction.

As shown in FIG. (outer flange part 38), and at this time, a gap of a predetermined length is formed in the axial direction between the ends 54, 54 of the cylindrical body 18°18. It is now possible to do so.

The inner cylindrical member 12 is also clearly shown in FIGS. 11 and 12, and the outer diameter of the inner cylindrical member 12 is
The inner diameter of the sleeve 16 is the same as or slightly smaller, and the length in the axial direction is slightly larger than the sleeve 16.

Therefore, the inner cylindrical member 12 is inserted into the cylindrical body 18.18 with its outer circumferential surface in contact with or very close to the inner circumferential surface of the cylindrical body 18.18. Relative rotation (sliding) between and the cylindrical bodies 18, 18 is allowed. Further, at both ends of the inner cylindrical member 12, as is clear from FIG.
Metal retaining rings 20.20 having a thickness that is approximately the same as the height of the cylindrical body 18 are press-fitted and fixed.
．． 18 is prevented from being pulled out to the outside in the axial direction. Although not shown, such an inner cylinder member 12
A suitable inner shaft is inserted into the inner shaft, and the inner shaft is attached to the vehicle body via a suitable support member such as a bracket.

By the way, in this way, the inner cylindrical member 12 is a hundred cylindrical body 18.1.
8, an annular space 56 surrounded by the inner cylinder member 12 and the sleeve 16 is formed between both ends 54 and 54, as shown in FIG. However, this space 56 may be filled with lubricating oil such as rubber grease or the like before insertion of the inner cylindrical member 12, or may be filled with lubricating oil applied to the sliding surface between the cylindrical body 18 and the inner cylindrical member 12. It is a place where things accumulate. In short, the space 56 functions as an oil reservoir for lubricating oil that lubricates the sliding surface between the cylindrical body 18 and the inner cylindrical member 12. body '18
．． 18, allowing them to smoothly rotate relative to each other and reducing wear on the sliding parts.

Furthermore, the groove 52 formed on the inner circumferential surface of the cylindrical body 18 is
In particular, it facilitates the movement of lubricating oil in the axial direction, and as a result, a good lubrication effect can be obtained even at both end portions in the axial direction separated from the space 56.

The space 56 has a size that can function as a lubricating oil reservoir, and the length of the cylindrical body 18 in the axial direction is determined as appropriate based on the size of the space 56. It is set.

As described above, a predetermined mounting shaft (inner shaft) is inserted into the inner cylindrical member 12 of the bushing assembly assembled in this way, and the control arm of the suspension to be tossed, for example, the A-arm, It will be attached to the vehicle body side as the front bush and lower bush of the arm.

In the bushing assembly configured as described above, the cylindrical extension portion 42.4 is connected to the metal fitting sealing member 24.24.
2 and the end of the inner cylindrical member 12, more specifically the retaining ring 20.20 press-fitted therein, to prevent soil, sand, muddy water, etc. from entering between the sleeve 16 and the inner cylindrical member 12. Since the intrusion of dirt, sand, muddy water, etc. is effectively prevented, there is no risk that the relative rotation between them by the cylinders 18, 18 will be impaired due to the intrusion of dirt, sand, muddy water, etc.

In particular, such a sealing member 24 is press-fitted into the inner circumferential surface of the cylindrical extension 42, and the retaining ring 24 at the end of the inner cylindrical member 12
Since it is designed to abut and press against the outer peripheral surface of 0, a good sealing effect can be obtained even when the two rotate relative to each other.In addition, since there is no input load on the sealing part, it is possible to Since the influence of axial loads is eliminated as much as possible, and even if the bushing assembly is subjected to radial loads, the cylindrical extension 42 and the retaining ring 20 will be displaced relative to each other in the radial direction. As a result, a constant sealing effect can always be obtained, and the sealing rubber 24
It is possible to minimize damage and wear of the product, thereby increasing its lifespan (durability). Moreover, the seal member 24 is provided with a plurality of lip portions 48, and abuts against the retaining ring 20 in a state of surface contact.
Since it is designed to be pressed, a reliable sealing effect can be obtained.

And, the seal member 2 with metal fittings exhibits these characteristics.
4 is constructed separately from the rubber block 14 of the bushing main body, so that the spring characteristics of the bushing can be freely selected, significantly increasing the degree of freedom.

In addition, since the cylindrical bodies 18.18 are press-fitted into the sleeve 16, the sleeve 16 functions as a resistor against deformation of the cylindrical bodies 18, thereby causing the cylindrical bodies 18.18 to be subjected to external vibration loads, etc. It does not deform or crack due to heat, always maintains a high roundness, ensures a good effect of reducing torsion spring action, and also plays a role in increasing durability against heat etc. , its lifespan can be effectively improved.

Furthermore, in this embodiment, a space 56 is formed between the ends 54, 54 of the cylindrical body 18.18, and this space 56 is filled with lubricating oil such as rubber grease that is gradually supplied to the sliding surface. Since it functions as a reservoir, the lubricating oil is sufficiently distributed over the entire sliding area between the cylindrical body 18.18 and the inner cylinder member 12, effectively reducing wear thereon, and the cylindrical body 18.18 The effect of reducing the torsional spring action is further improved. Moreover, in this embodiment, since the axial grooves 52 are formed on the inner circumferential surface of the cylindrical body 18.18, sufficient lubrication can be obtained even in the portions separated from the space 56. be.

In the above embodiment, the axial groove 52 is formed only on the inner circumferential surface of the cylindrical body 18.18, but as shown in FIGS. 13 and 14, in addition to the groove 52, hand,
By forming grooves 66 at four locations corresponding to the grooves 52 on the axially outer surface of the outer flange portion 50, the sliding portion between the outer flange portion 50 and the retaining ring 20, 20 can also be well lubricated. It will be done. Note that this groove 66 does not necessarily have to be formed in correspondence with the groove 52, and may be formed only as a groove 66.
Even if it is installed on the side, there is no problem.

Although the embodiments of the present invention have been described above in detail based on the drawings, the present invention may be implemented in other embodiments as well.

For example, in the embodiment described above, the fitting-equipped sealing member 24 is connected to the cylindrical extension portion 44 of the sleeve 16 at the fitting 44 portion thereof.
However, on the contrary, it is also possible to press fit into the outer peripheral surface of the retaining ring 20 so that the seal rubber 46 comes into contact with the inner peripheral surface of the cylindrical extension 42. .

Further, in the embodiment described above, a plurality of lip portions 48 are formed on the inner circumferential surface of the sealing member 24 to enhance the sealing effect. can be obtained.

Further, in the embodiment described above, the cylindrical body 18.18 and the inner cylinder member 12 are allowed to rotate relative to each other, but the cylindrical body 18.18 is fixed to the inner cylinder member 12, and the sleeve 16 is fixed to the inner cylinder member 12.
and the cylindrical body 18.18 can be rotated relative to each other, or the cylindrical body 18.18 is not fixed to either but can be rotated relative to both the sleeve 16 and the inner cylinder member 12. It is also possible to configure

Further, in the embodiment described above, the sliding members are two cylindrical bodies 18.
18, and a predetermined lubricant storage space 56 is formed between the ends 54 and 54, but it is not necessary to form the space 56, and the sliding member is formed into an integral cylinder. It can also be constructed from a shaped member.

Furthermore, in the embodiment described above, the cylindrical body 18.18 is made of oil-impregnated polyacetal resin, but it is of course also possible to use other oil-impregnated plastic materials or metal such as oil-impregnated bearing alloy.

In addition, in the above embodiment, seal members 24 and 24 are provided at both ends of the bushing assembly, but depending on the mounting position of the bushing assembly, etc., it is necessary to prevent muddy water etc. from entering from one end. In such a case, the sealing member 24 may be provided only at the other end.

In addition, although not illustrated, the present invention can be modified without departing from its spirit and based on the knowledge of those skilled in the art.
It goes without saying that the present invention can be implemented with modifications.

[Brief explanation of drawings]

FIG. 1 is an axial (longitudinal) cross-sectional view of a bushing assembly that is an embodiment of the present invention. FIG. 2 is an axial cross-sectional view showing the outer cylinder member of the bushing assembly of FIG. 1, and FIG. 3 is a view from the left in FIG. 4 is an axial cross-sectional view of the rigid sleeve member of the bushing assembly of FIG. 1, and FIG. 5 is a view taken from the right in FIG. 4; FIG. 6 is an axial cross-sectional view showing the bushing assembly of FIG. 1 in which an elastic member is vulcanized between the outer cylinder member and the rigid sleeve member. FIG. 7 is an axial sectional view of the sealing member with a fitting, and FIG. 8 is a right side view thereof. FIG. 9 is an axial sectional view showing the cylindrical body as a sliding member in the bushing assembly of FIG. 1, and FIG. 10 is a view from the right in FIG. 11 is an axial sectional view showing the inner cylinder member of the bushing assembly of FIG. 1, and FIG. 12 is a view from the right side in FIG. 11. FIG. 13 is a diagram illustrating a main part of another embodiment of the present invention, and is a front view showing a cylindrical body as a sliding member from the outer flange side, and FIG. 14 is a diagram showing XIV-X in FIG.
It is an enlarged view of IV cross section. 14: Rubber block (elastic member) 16: Sleeve (rigid sleeve member) 18 Two cylindrical bodies (sliding member)

Claims (5)

[Claims] (1) A predetermined elastic member is interposed between an inner cylinder member and an outer cylinder member that are positioned concentrically, and a torsion spring action by the elastic member is created between the elastic member and the inner cylinder member. A bushing assembly including a sliding member interposed therebetween, further comprising a rigid sleeve member interposed between the elastic member and the sliding member, and an end portion of the rigid sleeve member
It is composed of an outer flange extending radially outward and a cylindrical extension extending axially outward from the outer periphery of the outer flange, while the inner cylindrical member has an outer circumferential surface at the end thereof to allow the sliding member to come out. A retaining ring for blocking is press-fitted, and a ring-shaped sealing member with a fitting is interposed between the retaining ring and the cylindrical extension at the end of the rigid sleeve member to provide a seal therebetween. A bushing assembly comprising: (2) The sliding member is composed of two cylindrical bodies each having an outer flange portion extending radially outward at one end, and the outer flange portion of the two cylindrical bodies is located on the end side of the bushing assembly. When placed between the inner cylindrical member and the rigid sleeve member so that the outer flange portion of the two cylindrical bodies is located at A bushing assembly according to claim 1. (3) The elastic member is vulcanized and bonded to the inner circumferential surface of the outer cylinder member and the outer circumferential surface of the rigid sleeve member, respectively, to form an integral structure. Bushing assembly according to paragraph 2. (4) The bush assembly according to any one of claims 1 to 3, wherein the sliding member is made of an oil-impregnated plastic material. (5) The sealing mechanism between the end of the rigid sleeve member and the retaining ring by the sealing member with a metal fitting is provided at both ends of the bushing assembly in the axial direction, as claimed in claim 1. The bushing assembly according to any one of items 4 to 4.