JPS61127933A - Bush built-up body - Google Patents

Abstract

PURPOSE:To bring an intrinsic torsion spring acting reducing effect by a slide member into full play, by sealing a space between a large diametral cylinder part of a rigid sleeve and a cylindrical part of a retainer situated in an end part of an inner tube. CONSTITUTION:A rigid sleeve 16 is interposed between an elastic member 14 and slide members 18 and 20, while an end part of the rigid sleeve 16 is constituted of outer flange parts 40 and 42 extending outward in a radial direction and large diametral cylinder parts 44 and 46. And, cylindrical parts 74 and 76 are installed in retainers 22 and 24 being set up in an end part of an inner tube 12, while seal rubber devices 26 and 28 are installed in these large diametral cylinder parts 44 and 46 and either of cylindrical parts 74 and 76. With this constitution, since earth, sand, etc., are prevented from penetrating from these seal rubber devices 26 and 287, an intrinsic torsion spring action reducing effect by these slide members 18 and 20 can be brought into full play.

Description

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 of a vehicle suspension, such as a control arm bushing used in a connection between a control arm and a vehicle body or axle side member, is generally a concentric bushing assembly. A cylindrical elastic member made of a rubber material is interposed between two inner and outer cylindrical members that are arranged in a horizontal direction. designed to absorb vibrations. However, in such a bushing assembly, due to the torsional spring action of the elastic member, increasing the rigidity in the direction perpendicular to the axis also increases the torsional rigidity around the axis.

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 was impaired, and as a result, there was tremor that prevented the sliding member from fully exerting its effect of reducing the spring action.

(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 composed of an outer flange portion extending radially outward and a large diameter cylindrical portion extending axially from the outer peripheral edge of the outer flange portion to the other end side, while the inner cylinder A retainer member located at an end of the member includes a cylindrical portion located outside the large diameter cylindrical portion at a predetermined distance, and the outer peripheral surface of the large diameter cylindrical portion and the cylindrical portion A sealing rubber is provided on either side of the inner circumferential surface, and the sealing rubber is brought into contact with the other of the inner circumferential surfaces, thereby sealing between the large diameter cylindrical part and the cylindrical part. be.

(Function/Effect) In such a bushing assembly, a sealing rubber is provided between the large-diameter cylindrical portion of the rigid sleeve member and the cylindrical portion of the retainer member located at the end of the inner cylindrical member. The sliding member interposed between the rigid sleeve member and the inner cylindrical member, thereby effectively preventing soil, sand, muddy water, etc. from entering between them. The relative rotation between the rigid sleeve member and/or the inner cylinder member is not impaired, and therefore the sliding member's original effect of reducing the torsional spring action can be fully exhibited.

Moreover, the seal rubber provided between the outer circumferential surface of the large-diameter cylindrical portion of the rigid sleeve member and the inner circumferential surface of the cylindrical portion of the retainer member acts in the radial direction between the inner tube member and the outer tube member. Since it is not subjected to the load of Since there is no relative displacement in the radial direction, a constant sealing effect can always be obtained despite changes in the load applied in the radial direction.

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 the outside. Deformation (inner diameter change) and cracking of the sliding member due to vibration loads and the like are 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 sectional view showing an example of a bushing assembly according to the present invention. In this figure, reference numeral 10 denotes a cylindrical metal outer cylindrical member, and the innermost part of the bushing assembly is provided at a predetermined distance apart. 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 20 constituting sliding members are interposed between them. Retainer members 22 and 24 each having a substantially U-shaped cross section are attached to both ends of the inner cylindrical member 12, thereby assembling the bushing assembly and connecting the retainer members 22 and 24 to the sleeve 16. An annular seal rubber 26, 28 is provided between the ends.

Here, the outer cylinder member 10 is shown in FIGS. 2 and 3.
As clearly shown in the figure, it has a stepped cylindrical shape consisting of a small diameter part 30 and a large diameter part 32, and the end on the large diameter part 32 side has an outer surface extending radially outward. While a flange portion 34 is provided, a tapered surface 36 is formed at the end on the small diameter portion 30 side, and is press-fitted from the small diameter portion 30 side into a predetermined mounting hole of a control arm, etc. of a suspension arm (not shown). It is designed to be fixed.

Further, as clearly shown in FIGS. 4 and 5, the sleeve 16 includes a cylindrical portion 38 having a smaller diameter and longer axial length than the outer cylindrical member 10, and both ends of the cylindrical portion 38. outer flange portions 40. each extending radially outwardly from the outer flange portions 40.
42, and a large-diameter cylindrical portion 44.46 extending axially from the outer peripheral edge of the outer flange portion 40.42 toward the other end. The outer diameter of one outer flange portion 40 is larger than that of the other outer flange portion 42, and its assembly is located on the outer flange portion 34 side of the outer cylinder member 10, and The other outer flange portion 42
The outer diameter of the outer cylinder member 10 is smaller than the inner diameter of the small diameter portion 30 of the outer cylinder member 10.

The outer cylinder member 10 and the sleeve 16 are arranged concentrically, and the rubber block 14 is interposed between them. For example, as shown in FIG. 6, such a rubber pro 14 includes an outer cylinder member 10 and a sleeve 16 that are arranged concentrically, and a predetermined rubber material is applied within an annular space formed between them. Preferably, it is formed by sulfur molding. In this way, rubber block 1
Simultaneously with the formation of the outer cylinder member 10. The sleeve 16 and the rubber block 14 have an integral structure. Thereafter, the outer cylinder member 10 is subjected to a drawing process, and the rubber block 14 is pre-compressed, and the outer cylinder member 10, the rubber block 14, and the sleeve 16 are firmly fixed.

Here, in this embodiment, when the rubber block 14 is vulcanized, the sealing rubber 26, 28 is also
They are vulcanized and molded separately from the large diameter cylindrical portions 44 and 4, and are fixed and formed on the outer peripheral surfaces of the large diameter cylindrical portions 44 and 46, respectively. Further, a plurality of circumferential grooves 48.degree. 50 are formed on the outer peripheral surfaces of the seal rubbers 26.degree. 28, respectively, so that the sealing effect thereof can be fully exhibited. Note that the seal rubber 26, 28 can be integrally molded with the rubber block 14 by forming notches or the like in the large-diameter cylindrical portions 44 and 46, or they can be formed separately in advance and bonded. It may be fixed to the outer circumferential surface of the large-diameter cylindrical portion 44, 46 with an adhesive or the like.

On the other hand, as shown in FIGS. 7 to 10, each of the cylindrical bodies 18 and 20 has a cylindrical shape with an outer diameter that is approximately the same as the inner diameter of the sleeve 16, and one end thereof is provided with an outer flange portion 52.54 extending radially outward, and has an axial groove 56.58 on its inner peripheral surface.
are formed at equal angular intervals in the circumferential direction. These cylindrical bodies 18.20 are press-fitted into the cylinder of the sleeve 16 from the end portion 60.62 on the side where the outer flange portion 52.54 is not provided, and the outer flange portion 52.5
4 is fixed to the sleeve 16 in a state where it is in contact with the end of the sleeve 16;
A gap of a predetermined length is formed in the axial direction between the end portions 60 and 62 of 20. Further, the cylindrical body 18 is press-fitted into the end of the sleeve 16 on the outer flange portion 40 side, and its axial length is smaller than that of the cylindrical body 20, but the outer flange portion 52 is One outer flange portion 40 of 16 is larger than the other outer flange portion 42 and correspondingly larger than outer flange portion 54 of cylindrical body 20.

The inner cylindrical member 12, also clearly shown in FIGS. 11 and 12, has an outer diameter similar to that of the cylindrical body 18.20.
The inner diameter is the same as or slightly smaller, and the length in the axial direction is the same as or slightly larger than the length to both outer ends of the true cylindrical body 18.20 press-fitted into the sleeve 16. has been done. Therefore, the inner cylindrical member 12 has its outer circumferential surface in contact with or very close to the inner circumferential surfaces of the true cylindrical bodies 18 and 20.
．． 20, and relative rotation (swinging) between the inner cylinder member 12 and the cylindrical body 18, 20 is allowed. Although not shown, a suitable inner shaft is inserted into the inner cylinder member 12, 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 curved member 12 is a true cylindrical body 18.2.
0, an annular central space 64 surrounded by the inner cylinder member 12 and the sleeve 16 is formed between the two ends 60 and 62; A lubricating oil such as rubber grease is filled in prior to insertion of the inner cylinder member 12, or a place where lubricant oil applied to the sliding surfaces of the cylinder body 18, 20 and the inner cylinder member 12 accumulates. be. In short, this space 64 functions as an oil reservoir for lubricating oil that lubricates the sliding surface between the cylindrical body 18.20 and the inner cylinder member 1-2. 12 and the true cylindrical bodies 18 and 20, allowing them to rotate relative to each other smoothly and reducing wear on the sliding parts.

Additionally, a groove 5 formed on the inner circumferential surface of the cylindrical body 18.20
6 and 58 facilitate the movement of the lubricating oil especially in the axial direction, and as a result, a good lubrication effect can be obtained even at both ends in the axial direction separated from the space 64. . The space 64 has a size that can function as a lubricating oil reservoir, and the length of the cylindrical body 18.20 in the axial direction is determined based on the size of the space 64. Each is set.

Retainer members 22.24 are attached to both ends of the inner cylindrical member 12, and as clearly shown in FIGS. 13 to 16, the retainer members 22.24 are Donut-shaped disk portion 6
6.68, an inner cylindrical portion 70.72 that extends perpendicularly from the inner peripheral edge of the disk portion 66.68 and has an outer diameter approximately the same as the inner diameter of the inner cylinder member 12, and a disk portion. 66. From the outer peripheral edge of 68 to the inner cylindrical part To, ? 2 and outer cylindrical portions 74 and 76 extending in the same direction, and has a substantially U-shaped cross section. Note that the outer diameters of the disk portions 66 and 68 are the same as those of the outer flange portions 40 and 4 of the sleeve 16, respectively.
2, and the length of the outer cylindrical portion 74, 76 is large enough that the inner circumferential surface thereof can face the outer circumferential surface of the large diameter cylindrical portion 44, 46 of the sleeve 16 in the assembled state. It is said that

Such retainer member 22,24 has an inner cylindrical portion 70.
．． 72 are press-fitted into both ends of the inner cylinder member 12, thereby being fixed to the ends of the inner cylinder member 12, respectively. At this time, the outer circumferential surfaces of the seal rubbers 26 and 28 are brought into contact with the inner circumferential surfaces of the outer cylindrical portions 74 and 76, which are opposed to the outer circumferential surfaces of the large diameter cylindrical portions 44 and 46, respectively, and the seal rubber 26. 28 is compressively deformed between them. As a result, these outer cylindrical portions 74 and 76 and the large diameter cylindrical portion 44
．． An effective seal is formed between the sleeve 1
Dirt, sand, muddy water, etc. are prevented from entering between 6 and the inner cylinder member 12. The thickness of the seal rubber 26.28 is the same as that of the outer cylindrical portion 74.76 and the large diameter cylindrical portion 4, respectively, as described above.
The size is such that it can be compressed and deformed between 4.46 mm and a reliable sealing effect.

Further, the disc portions 66° 68 of the retainer members 22, 24 are
Since the length of the inner cylindrical member 12 is the same as or slightly larger than the length between the outer ends of the cylindrical body 18.20 press-fitted into the sleeve 16, the cylindrical body 18.2
The outer flange portions 52 and 54 of 0 are opposed to each other in contact with or in close proximity to each other, and their relative rotation is permitted. Furthermore, an annular end space 78.
80 is formed, and these end spaces 78.80 function as oil reservoirs for lubricating oil like the space 64, so that the space between the retainer member 22.24 and the cylindrical body 18.20 is well lubricated. At the same time, by filling the end space 78.80 with lubricating oil, the outer cylindrical portion 74.76 and the large diameter cylindrical portion 44.46 are more effectively sealed.

Note that the space 64 is provided at a position slightly closer to the retainer member 22 side, so that the retainer member 2
The outer flange portion 52 of the cylindrical body 18 and the retainer member 22, which has a larger sliding area than the fourth side, are also well lubricated.

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 is used to attach the control arm of the intended suspension, such as 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 seal rubber 26.28 seals between the large diameter cylindrical portion 44.46 and the outer cylindrical portion 74.76, and the sleeve 16.
Since the intrusion of soil, sand, muddy water, etc. between the inner cylinder member 12 and the inner cylinder member 12 is effectively prevented, the relative rotation between them by the cylindrical body 18, 20 prevents the intrusion of the soil, sand, muddy water, etc. There is no damage caused by this. In particular, the seal rubber 26.28 is provided on the outer peripheral surface of the large-diameter cylindrical portion 44.46 of the sleeve 16, so as to be brought into contact with and pressed against the inner peripheral surface of the outer cylindrical portion 74.76 of the retainer member 22.24. Because of this, a good sealing effect can be obtained even when the two rotate relative to each other, and even if the bushing assembly receives a load in the radial direction, the large diameter cylindrical portion 44.
6 and the outer cylindrical portions 74, 76 are not displaced relative to each other in the radial direction, a constant sealing effect can always be obtained, and wear of the seal rubber 26, 28 can be minimized. This can improve lifespan. Moreover, the seal rubbers 26, 28 are each provided with a plurality of grooves 48, 50, and the outer cylindrical portion 7
4.76, so that a reliable sealing effect can be obtained.

Further, since the cylinders 18, 20 are press-fitted into the sleeve 16, the sleeve 16 is inserted into the cylinders 18, 2.
It functions as a resistor against the deformation of Q, so that the cylindrical bodies 18 and 20 are not deformed or cracked due to external vibration loads, etc., and maintain a high roundness at all times. This not only ensures a good effect of reducing the torsion spring action, but also serves to enhance durability against heat and the like, thereby effectively increasing its lifespan.

Further, in this embodiment, spaces 64.78° 80 are formed at the ends 60, 62 of the cylindrical bodies 18, 20 and radially outward of the outer flange portions 52, 54, respectively, and these spaces 64, 78. 80 functions as an oil reservoir for lubricating oil such as rubber grease that is gradually supplied to the sliding surface, so that the entire sliding group between the cylindrical body 18.20, the inner cylinder member 12, and the retainer member 22.24 is The lubricating oil will be sufficiently distributed, their wear will be effectively reduced, and the effect of reducing the torsion spring action by the cylindrical body 18, 20 will be further improved. Moreover, in this embodiment, the inner peripheral surface of the cylindrical body 18.20 is provided with grooves 56.58 in the axial direction.
Since this is formed, sufficient lubrication can be obtained even in a portion remote from the space 64.

In the above embodiment, the axial groove 56 is formed only on the inner circumferential surface of the cylindrical body 18.
As shown in the figure, in addition to the groove 56, there are four holes on the axially outer surface of the outer flange portion 52 that correspond to the groove 56.
By forming concave grooves 82 at these locations, which communicate the grooves 56 with the end space 78, the sliding portion between the outer flange portion 52 and the retainer member 22 will be more effectively lubricated. Note that this groove 82 does not necessarily have to be formed in correspondence with the groove 56, and even if it is only communicated with the end space 78, the same lubricating effect can be obtained. Also,
Of course, by forming a similar groove in the outer flange portion 54 of the other cylindrical body 20, the sliding portion between the outer flange portion 54 and the retainer member 24 is well lubricated.

Although one embodiment of the present invention has been described above in detail based on the drawings, the present invention can be implemented in other embodiments as well.

For example, in the embodiment described above, the seal rubbers 26 and 28 are respectively provided on the outer peripheral surface of the large diameter cylindrical portion 44 and 46, but there is no problem if the seal rubbers 26 and 28 are provided on the inner peripheral surface of the outer cylindrical portion 74 and 76. .

Furthermore, in the embodiment described above, a plurality of grooves 48.50 are formed on the outer circumferential surface of the seal rubber 26.28 to enhance the sealing effect. can get.

Further, in the embodiment, the cylindrical body 18.20 and the inner cylindrical member 1
However, the cylindrical body 18.20 may be fixed to the inner cylindrical member 12 so that the sleeve 16 and the cylindrical body 18.20 can be rotated relative to each other. It is also possible to configure the body 18,20 not to be fixed to either, but to be able to rotate relative to both the sleeve 16 and the inner cylinder member 12.

Furthermore, in the embodiment, the sliding member is composed of two cylindrical bodies 18.
．． 20, and a predetermined lubricating oil storage space 64 is formed between the end portions 60 and 62, but it is not necessary to form the space 64, and the sliding member is integrally formed. It can also be constructed from a cylindrical member. Furthermore, the end spaces 78 and 80 do not necessarily need to be formed in the same way.

Furthermore, in the embodiment described above, the cylindrical bodies 18 and 20 are made of oil-impregnated polyacetal resin, but they can also be made of other oil-impregnated plastic materials or metals such as oil-impregnated bearing alloys.

Further, in the above embodiment, seal rubbers 26 and 28 are provided at both ends of the bushing assembly, but if muddy water or the like cannot enter from one end due to the mounting position of the bushing assembly, etc. Seal rubber 2 only on the other end
6 or 28 may be provided.

Furthermore, in the embodiment, the retainer members 22 and 24 are
Although the inner cylindrical portion 70.72 allows attachment to the inner cylindrical member 12, it is possible to attach the bushing assembly to a predetermined mounting shaft without such an inner cylindrical portion 70.72. The retainer member is tightened and fixed to the inner cylinder member 12 by screwing a nut or the like, or by press-fitting a collar having a flange into the inner cylinder member 12, the retainer member is attached to the flange. There is no problem even if it is fixed by being sandwiched between it and the inner cylinder member 12.

Although other examples will not be given, it goes without saying that the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit thereof.

[Brief explanation of the drawing]

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 sectional view showing the outer cylinder member of the bushing assembly in FIG. 1, and FIG.
This is a recovery from the right side in the figure. 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 side of 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. 7 is an axial sectional view showing one cylindrical body as a sliding member in the bushing assembly of FIG. 1, and FIG. 8 is a view taken from the right side in FIG. 7. 9 is an axial sectional view showing the other cylindrical body of the bushing assembly of FIG. 1, and FIG.
This is a recovery from the right side in the figure. FIG. 11 is an axial cross-sectional view showing the inner cylinder member of the bushing assembly of FIG. 1;
Figure 12 shows a recovery from the right side in Figure 11. 13 is an axial sectional view showing one retainer member of the bushing assembly of FIG. 1, and FIG. 14 is a view taken from the right side in FIG. 13. FIG. 15 is an axial sectional view showing the other retainer member of the bushing assembly of FIG. 1, and FIG. 16 is a view taken from the left in FIG. 15. FIG. 17 is a diagram illustrating the main parts of another embodiment of the present invention, and is a front view showing one cylindrical body as a sliding member from the outer flange side, and FIG. It is an enlarged cross-sectional view of ■-X■. 10: Outer cylinder member 12: Inner cylinder member 14: Rubber block (elastic member) 16: Sleeve (rigid sleeve member) 18.20: Cylindrical body (sliding member) 22.24: Retainer member 26.28: Seal rubber 40. 42: Outer flange part 44.46: Large diameter cylindrical part 52.54: Outer flange part 64: Space (center space) 74.76: Outer cylindrical part (cylindrical part) 78.80: End space FIG. Figure 14 Figure 17 Figure 18

Claims (6)

[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
A retainer, which is composed of an outer flange portion extending radially outward and a large diameter cylindrical portion extending axially from the outer periphery of the outer flange portion to the other end side, and located at an end portion of the inner cylindrical member. The member is configured to include a cylindrical part located outside the large diameter cylindrical part at a predetermined distance, and on either the outer circumferential surface of the large diameter cylindrical part or the inner circumferential surface of the cylindrical part. 1. A bushing assembly characterized in that a sealing rubber is provided and the sealing rubber is brought into contact with the other of the two to achieve sealing between the large diameter cylindrical part and the cylindrical part. (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. A predetermined central space is formed between the ends of the two cylindrical bodies where the outer flange portion is not provided when the inner cylinder member and the rigid sleeve member are positioned so as to A bushing assembly according to claim 1, wherein the bushing assembly has the following features. (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) An end space sandwiched between the retainer member and the rigid sleeve member is formed between the seal rubber and the outer flange portion of the cylindrical body constituting the sliding member. Bush assembly according to item 2. (6) A sealing mechanism between the large-diameter cylindrical portion of the rigid sleeve member and the cylindrical portion of the retainer member using the seal rubber is provided at both ends of the bushing assembly in the axial direction. The bushing assembly according to any one of items 1 to 5.