JPH0237285Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a bushing assembly that is interposed between a pivot shaft and a cylindrical member constituting a vibration transmission system and connects them in a vibration-proof manner. A spherical sliding bushing assembly with a built-in sliding mechanism that effectively absorbs torsional and twisting forces applied between the pivot shaft and the cylindrical member while connecting them in a vibration-proof manner. It is.

(Prior art) Conventionally, a predetermined vibration isolation bushing has been interposed between a pivot shaft and a cylindrical member that constitute a vibration transmission system.
The structure that connects these pivots and the cylindrical member with vibration isolation is
A variety of methods have been adopted. For example, in an automobile suspension, suspension members such as various arms, rods, and links are attached to be able to swing in various directions in order to suspend differential gears, wheels, etc. from the vehicle body. A suspension bushing made of rubber material is generally incorporated into the pivot joint of a suspension member, that is, the pivot connection to the vehicle body, axle, or vehicle body, for the purpose of mitigating vibrations. There is.

By the way, in a vibration-proof bushing such as such a suspension bushing, conventionally, there is an inner cylindrical metal fitting into which a predetermined pivot shaft is inserted, and an inner cylinder metal fitting disposed on the outside of the inner cylindrical metal fitting.
Generally, a structure in which a cylindrical elastic member is interposed between an outer cylindrical metal fitting fitted into a predetermined cylindrical member has been adopted, but in such a conventional bushing structure, If the rigidity in the direction perpendicular to the axis is increased with emphasis on anti-vibration performance, the torsional rigidity around the axis will also increase, impairing the rotational performance between the pivot and the cylindrical member, and conversely, increasing the rigidity in the direction perpendicular to the axis. It has been said that if the torsional rigidity around the axis is lowered in order to improve the rotational performance between the cylinder and the cylindrical member, the rigidity in the direction perpendicular to the axis will also be lowered, making it impossible to obtain good vibration isolation performance. There was a problem.

Therefore, in recent years, with the aim of solving such problems with conventional bushings, a predetermined sliding sleeve is fitted inside or outside the elastic member, and the elastic member is attached to the pivot or cylindrical member. Bush assemblies that can be easily rotated around an axis have been proposed. According to such a bushing assembly, it is possible to reduce the torsional rigidity between the pivot and the cylindrical member, regardless of the rigidity in the direction perpendicular to the axis of the elastic member, thereby improving vibration isolation performance and rotation performance. Both can be obtained in good condition.

(Problem) However, even with this improved bushing assembly, if a force is applied in a direction oblique to the bush axis, a so-called twisting force, the sliding movement of the sliding sleeve may be affected. There was a problem that the function was not fully expressed and the rotational performance between the pivot and the cylindrical member deteriorated.

On the other hand, in contrast to this, a so-called spherical sliding type bushing assembly has been considered in which a spherical sliding mechanism is built inside the elastic member. By incorporating a spherical sliding function inside the elastic member, the spherical sliding mechanism can absorb forces in the torsional and twisting directions, resulting in good rotational performance even when forces in the twisting direction are applied. Therefore, it is possible to stably obtain both good vibration damping performance and vibration damping performance.

However, in this type of spherical sliding bush assembly, if foreign matter such as dirt, dust, or muddy water enters the spherical sliding part, the spherical sliding performance will be impaired, and the spherical sliding performance will be damaged. It is necessary to prevent these foreign substances from entering the spherical sliding part, since this would impair rotational performance, and for this purpose, it is necessary to seal the spherical sliding part from the outside space. If such a sealing function is to be provided, the structure of the bushing assembly will become complicated, the number of parts will increase, and the assembly work efficiency will be reduced. As a mass-produced product, its productivity was far from satisfactory.

(Solution Means) Against this background, the present invention has been developed to provide a sealing function to a spherical sliding part, which has excellent assembly workability and can reduce the number of parts as much as possible. In addition, it was designed to provide a spherical sliding bushing assembly suitable for use in areas where the amount of relative displacement between the pivot and the cylindrical member is small, and its features are as follows:
As mentioned above, in the bushing assembly that is interposed between the pivot shaft and the cylindrical member constituting the vibration transmission system and connects them in a vibration-proof manner, (a) a spherical convex surface is provided on the outer peripheral surface of the intermediate portion in the axial direction; (b) a cylindrical race fitting arranged concentrically at a predetermined distance on the outside of the inner cylinder fitting; (c) an inner cylinder fitting through which the pivot shaft is inserted; It has a spherical concave surface corresponding to the spherical convex surface of the inner cylindrical metal fitting, and is slidably fitted to the spherical convex surface of the inner cylindrical metal fitting on the spherical concave surface, and the inner periphery of the axially intermediate portion of the race fitting on the outer peripheral surface. (d) a cylindrical sliding member fitted into the surface; and (d) fitted into the inner circumferential surfaces of both ends of the race fitting in the axial direction, and firmly clamping the sliding member in the axial direction of the bush. (e) between the pair of presser sleeves and the inner cylindrical metal fitting, one end side of each is fluid-tightly attached to the inner circumferential surface of each corresponding presser sleeve, and the other end A pair of generally cylindrical or annular shaped plates whose sides are attached to the outer circumferential surface of the inner cylindrical fitting corresponding to each of the presser sleeves and seal the annular gaps between the corresponding presser sleeves and the inner cylindrical fitting. (f) is press-fitted into the outer peripheral surface of the inner cylindrical metal fitting corresponding to each presser sleeve, and the other end side of the sealing member is held in the direction of the bush axis, and the inner cylindrical metal fitting is each pair of rigid rings fluid-tightly fixed to the outer peripheral surface;
(g) a cylindrical elastic member disposed on the outside of the race metal fitting to elastically hold the race metal fitting to the cylindrical member;

(Function/Effect) In such a spherical sliding bushing assembly, the inner cylinder fitting is slidably fitted and held on the spherical convex surface to the spherical concave surface of the sliding member. The torsional and twisting forces input between the cylindrical member and the cylindrical member are well absorbed by the spherical sliding between the spherical convex surface and the spherical concave surface. Since the elastic member is attached to the cylindrical member, good vibration damping performance can be obtained based on the elastic deformation action of the elastic member, regardless of the presence or absence of forces in the torsion and twisting directions.

Further, according to the spherical sliding bushing assembly according to the present invention, the annular gaps between the inner cylindrical metal fitting and each presser sleeve that clamps the sliding member in the axial direction are each closed by the sealing member. Since it is sealed, foreign matter such as dirt, dust, and muddy water can be effectively prevented from entering the spherical sliding area between the spherical convex surface and the spherical concave surface, thereby improving the spherical sliding performance and, ultimately, the shaft and cylinder. This prevents the rotary performance between the sealing member and the sealing member from being impaired due to the intrusion of such foreign matter. Directly against the circumferential surface, and the other end side is held against the outer circumferential surface of the inner cylindrical fitting by a pair of rigid rings that are press-fitted into the outer periphery of the inner cylindrical fitting. Since it can be attached to a wall, it has the advantage that the reliability of the sealing function is extremely high.

Moreover, in the present invention, as described above, one end side of each seal member is attached to the presser sleeve for fixedly holding the sliding member. It has the advantage of being able to reduce the number of parts, and by extension the number of parts of the bushing assembly, as much as possible, and due to its structure, the sealing member can be held against the presser sleeve by lacing the presser sleeve. It can be attached before fitting into the metal fitting, and it can be easily fixed to the inner cylinder metal fitting by press-fitting the rigid sleeve into the inner cylinder metal fitting, so it has excellent assembly workability. It is. Therefore, good productivity can be obtained in addition to the effect of reducing the number of parts.

As mentioned above, in the spherical sliding bushing assembly according to the present invention, since the seal members are fixedly attached to the race metal fitting and the inner cylinder metal fitting, the seal member is fixedly attached to the race metal fitting and the inner cylinder metal fitting. However, as long as the amount of relative displacement thereof is within the permissible displacement range of the sealing member, it can be used effectively.

(Example) Hereinafter, in order to clarify the present invention more specifically, one example thereof will be described in detail based on the drawings.

First, FIG. 1 shows an example of a suspension bushing for an automobile suspension, which is a spherical sliding bushing assembly according to the present invention.
As shown therein, the suspension bush of the present embodiment includes a cylindrical inner metal fitting 10 and a cylindrical metal fitting 10 that is concentrically arranged at a predetermined distance on the outside of the inner metal fitting 10. a lace fitting 12, a rubber sleeve 14 as an elastic member press-fitted to the outer peripheral surface of the race fitting 12, a cylindrical outer tube fitting 15 press-fitted to the outer periphery of the rubber sleeve 14, and the lace fitting 12. a sliding sleeve 16 as a sliding member disposed between the metal fitting 12 and the inner cylinder metal fitting 10 and holding the inner cylinder metal fitting 10 in a spherical slidable manner;
The sliding sleeves 16 are attached to the inner circumferential surfaces of both ends of the race fitting 12 in the axial direction.
A pair of metal presser sleeves 18, 18 fixedly clamped in the axial direction, and a sealing member that seals the annular gap between the presser sleeves 18, 18 and the inner cylindrical fitting 10, respectively. A pair of substantially cylindrical seal rubbers 20, 20, and one end side of these seal rubbers 20, 20 are attached to the inner cylinder fitting 1.
0 in cooperation with each other and fixed to the outer circumferential surface. Each pair of metal rings 23 and 24 serve as rigid rings. In the inner hole 26 of the inner cylindrical fitting 10, it is fitted onto a pivot (not shown) constituting a vibration transmission system, and at the same time, on the outer circumferential surface of the outer cylindrical fitting 15, it is shown as a cylindrical member constituting the vibration transmission system. The pivot shaft is inserted into the arm eye of the suspension arm that is not connected to the suspension arm, and is attached to the arm eye of the suspension arm to provide a vibration-proof connection between the pivot shaft and the arm eye of the suspension arm.

Here, as shown in FIG. 2, the inner cylindrical metal fitting 10 is provided with a spherical convex surface 30 on the outer circumferential surface of the central portion in the axial direction, and on both sides of the spherical convex surface 30 in the axial direction. The outer circumferential surfaces of both ends thereof are cylindrical surfaces 32, 32.

The race fitting 12 also has thin caulked portions 34, 34 at both ends in the axial direction, as shown in FIG. 3 in its shape before the bushing is assembled.
At the axial center of the inner periphery thereof, over a length portion approximately corresponding to the width of the spherical convex surface 30 of the inner cylindrical fitting 10, the inner diameter thereof is greater than that of the axially opposite side portions. The small diameter part 3 is also made smaller.
6 (see Fig. 1), and has stepped surfaces 40 facing outward in the axial direction between the small diameter portion 36 and the large diameter portions 38, 38 on both sides in the axial direction. ing. The rubber sleeve 14 is press-fitted onto the outer peripheral surface of the race fitting 12, and the outer cylindrical fitting 15 is fitted into the band-shaped groove 41 formed on the outer periphery of the rubber sleeve 14. Press-fitted and fixed. Note that the rubber sleeve 14 is attached to the race fitting 12 and the outer cylinder fitting 1.
It is also possible to integrally fix one or both of the parts 5 by integral vulcanization molding, post-adhesion, or the like.

On the other hand, as shown in FIGS. 4 and 5, the sliding sleeve 16 has a spherical concave surface 42 corresponding to the spherical convex surface 30 of the inner cylindrical fitting 10 on the inner circumferential surface of the central portion in the axial direction. The spherical concave surface 42 is slidably fitted into the spherical convex surface 30 of the inner cylinder fitting 10, and the outer peripheral surface thereof is press-fitted into the small diameter portion 36 of the race fitting 12. There is. Due to the slidable fitting between the spherical convex surface 30 and the spherical concave surface 42, the inner cylindrical fitting 10 and the sliding sleeve 16, and eventually the inner cylindrical fitting 10.
The pivot shaft inserted through the outer cylinder fitting 15 and the arm eye of the suspension arm fitted on the outer circumferential surface of the outer cylinder metal fitting 15 are configured to be able to slide on a spherical surface. In this embodiment, this sliding sleeve 1
6 in the axial direction is the small diameter portion 3 of the race fitting 12
6, and as shown in FIG. It is arranged to be flush with the stepped surfaces 40, 40.

Further, as shown in FIGS. 4 and 5, a plurality of grooves 44 extending in the axial direction are formed on the inner peripheral surface of the sliding sleeve 16 at predetermined intervals in the circumferential direction. The presence of these grooves 44 allows the sliding sleeve 16 to be easily fitted into the inner cylinder fitting 10. Further, grease is normally applied to the spherical convex surface 30 and the spherical concave surface 42, and the groove 44 also functions as a grease reservoir.

Note that such a sliding sleeve 16 includes:
Generally, a resin material with a small coefficient of friction, such as nylon resin, polyacetal resin, or oil-impregnated polyacetal resin, is used.

Further, as shown in FIG. 6, each of the presser sleeves 18, 18 has a protrusion 4 located at one end in the axial direction and protrudes inward in the radial direction.
6, as shown in Figure 1,
They are press-fitted into the large diameter portions 38, 38 of the race fitting 12 with their end surfaces on the side of the protrusions 46, 46 abutting the stepped surfaces 40, 40 of the race fitting 12 and the end surface of the sliding sleeve 16, respectively. ing.
The lace fitting 12 is fixed to the race fitting 12 by roll caulking of the caulking portions 34, 34 provided at both ends of the race fitting 12. By being fixed to the race fitting 12 in this manner, the sliding sleeve 16 is fixedly clamped in the axial direction, and the sliding sleeve 16 is fixed to the race fitting 12.

Furthermore, as shown in FIG. 7, the seal rubbers 20, 20 each have a substantially S-shaped cross section with slack in the center in the axial direction, and the ends facing outward in the radial direction. The presser sleeves 18, The annular gap between 18 and the cylindrical metal fitting 10, that is, the spherical sliding portion between the spherical convex surface 30 and the spherical concave surface 42, is fluid-tightly sealed from the external space.

As shown in FIG. 6, an annular groove 48 that opens on the inner peripheral surface is formed in the protrusion 46 of each presser sleeve 18, and as shown in FIG. Each seal rubber 20 has its radially outward end side accommodated in its annular groove 48, and the axial direction (of the presser sleeve 18) sandwiching the annular groove 48.
By caulking the thin wall 50 on the center side, it is fixed in the annular groove 48 in a fluid-tight manner. Further, the radially inward end side of each seal rubber 20 is attached to a pair of metal rings 22 and 24 that are press-fitted and fixed to the cylindrical surface 32 of the inner cylindrical fitting 10, respectively, as shown in FIG. Therefore, it is clamped and fixed in the axial direction. By fixing the seal rubbers 20, 20 at their respective cylindrical ends in a fluid-tight manner, dust and dirt are removed from the spherical sliding portion.
The intrusion of foreign substances such as muddy water is reliably and stably prevented over a long period of time.

The radially outward end of each seal rubber 20 is fixed to the corresponding presser sleeve 18 by caulking before the presser sleeve 18 is attached to the race fitting 12. Also,
Each pair of metal rings 22 and 24 that fix the radially inward end side of each seal rubber 20 to each corresponding cylindrical surface 32 of the inner cylindrical fitting 10 is normally provided on the axially inner side of the inner cylindrical fitting 10. The lace fittings 12 of each presser sleeve 18 are
are press-fitted into the inner cylindrical fittings 10 before being attached to the
After the presser sleeve 18 is attached, the axially outer part 24 is press-fitted into the inner cylindrical fitting 10.

As explained above, according to the suspension bushing of this embodiment, the inner tube fitting 10 is slidably held on the spherical concave surface 42 of the sliding sleeve 16 at the spherical convex surface 30 on its outer circumference, so that vibrations The force in the torsional direction and the twisting direction applied between the pivot shaft that constitutes the transmission system and the arm eye of the suspension arm is effectively absorbed by their spherical sliding, and therefore the force in the twisting direction and the twisting direction is effectively absorbed. Regardless of the presence or absence of a directional force, a good vibration damping effect can be obtained based on the elastic deformation action of the rubber sleeve 14 against vibrations input between the pivot shaft and the arm eye.

Further, according to the suspension bushing of this embodiment, as described above, the spherical convex surface 30 and the spherical concave surface 4
Seal rubbers 20, 20 for sealing the spherical sliding parts between the two from the external space are attached to the inner circumferential surface of the corresponding presser sleeve 18 on one end side, and on the inner cylindrical metal fitting on the other end side. The spherical convex surface 3 is fixedly fixed in a fluid-tight manner to the outer circumferential surface (cylindrical surface 32) of each corresponding axial end of the
Dust on the spherical sliding part between 0 and the spherical concave surface 42,
It is designed to reliably and stably prevent the intrusion of foreign substances such as dust and muddy water over a long period of time, thereby improving the rotation performance between the pivot and the arm eye of the suspension arm over a long period of time. Another advantage is that it can be held well.

Furthermore, in this embodiment, as described above, one end side of each seal rubber 20 is directly attached to the presser sleeve 18 for fixedly holding the sliding sleeve 16.
0 and 20, and by extension, the number of parts for the suspension bushing.In addition, each seal rubber 20 is attached to each presser sleeve 18, and the presser sleeve 18 is attached to the race fitting 12. In addition to being able to be attached to the front, it can be fixed to the inner cylinder fitting 10 with a simple operation of press-fitting each pair of metal rings 22 and 24 into the inner cylinder fitting 10, so the assembly workability is excellent. There is. Therefore, it is possible to obtain good productivity in addition to the above-mentioned effect of reducing the number of parts.

Moreover, in this embodiment, as described above, each seal rubber 20 has a cylindrical shape with a substantially S-shaped cross section that is easily deformed, and its radially outward end side is located at the bush axis of each presser sleeve 18. Since the deformation amount of each seal rubber 20 due to the relative displacement between the inner cylinder fitting 10 and the race fitting 12 is fixed to the end on the center side in the direction, the amount of deformation of each seal rubber 20 due to the relative displacement between the inner cylinder fitting 10 and the race fitting 12 is made as small as possible. 20, and by extension, the life of the suspension bushing.As is clear from FIG. metal ring 2
2 and 24 have the same shape and are compatible with each other, which also has the advantage of being excellent in mass production.

In addition, the suspension bushing of this example is as follows:
It can be particularly suitably used for parts where the relative displacement between the arm eye and the pivot is small, but the seal rubber 20, 20
Any part that is within the allowable displacement range can be used effectively.

Although one embodiment of the present invention has been described above, this is a literal illustration, and it goes without saying that the present invention should not be interpreted as being limited to this specific example.

For example, in the embodiment described above, the seal rubber 20 as a sealing member has a substantially cylindrical shape, but the sealing member does not necessarily have to have a substantially cylindrical shape, but may have a substantially annular shape. It is okay to do so.

Further, in the embodiment described above, the seal rubber 20 is fixed to each presser sleeve 18 by caulking one end thereof, but the seal rubber 20 has one end secured to the presser sleeve 18 by vulcanization adhesion.
It may be integrally fixed to the.

Further, in the embodiment described above, each presser sleeve 18, 18 is fixed to the race fitting 12 by roll caulking of the caulking portions 34, 34 provided at the ends of the race fitting 12. However, the presser sleeves 18, 18 can also be simply press-fitted and fixed to the race fitting 12.

Further, in the embodiment described above, an outer cylindrical metal fitting 15 is further provided on the outside of the rubber sleeve 14 as an elastic member, and the suspension bushing is attached to the outer cylindrical metal fitting 15.
However, the present invention is not limited to this, and the present invention is not limited to this type of bushing in which the bushing is directly attached to the cylindrical member on the outer peripheral surface of the elastic member. It can also be applied.

Furthermore, in the above embodiment, an example was explained in which the present invention was applied to a suspension bush for an automobile suspension, but the present invention is not limited to this. It can be widely applied to bush assemblies that connect members with each other in a vibration-proof manner.

Although not listed in detail, it goes without saying that the present invention can be implemented with various changes, modifications, improvements, etc. without departing from the spirit thereof.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view (a sectional view parallel to the axis) showing an example of a suspension bushing for an automobile suspension according to the present invention, and Fig. 2 shows an inner cylindrical metal fitting of the bushing shown in Fig. 1. FIG. FIG. 3 is a cross-sectional view showing the race fitting of the bush of FIG. 1 before the bush is assembled. FIG. 4 is a cross-sectional view showing the sliding sleeve of the bush in FIG.
Fig. 5 is a cross-sectional view of the figure.
FIG. 6 and 7 are cross-sectional views showing the holding sleeve and seal rubber of the bush of FIG. 1, respectively. 10: Inner cylinder metal fitting, 12: Race metal fitting, 14: Rubber sleeve (elastic member), 15: Outer cylinder metal fitting, 1
6: Sliding sleeve (sliding member), 18: Presser sleeve, 20: Seal rubber (sealing member), 22,
24: metal ring (rigid ring), 30: spherical convex surface, 32: cylindrical surface, 34: caulked portion, 42: spherical concave surface, 46: protruding portion, 48: annular groove, 50: thin wall.

Claims (1)

[Claims for Utility Model Registration] A bushing assembly that is interposed between a pivot shaft and a cylindrical member constituting a vibration transmission system and connects them in a vibration-proof manner, and has a spherical shape on the outer peripheral surface of the intermediate part in the axial direction. having a convex surface;
an inner cylindrical metal fitting through which the pivot shaft is inserted; a cylindrical race metal fitting concentrically arranged at a predetermined distance on the outside of the inner cylindrical metal fitting; and an inner peripheral surface corresponding to the spherical convex surface of the inner cylindrical metal fitting. a spherical concave surface, which is slidably fitted onto the spherical convex surface of the inner cylinder fitting;
a cylindrical sliding member fitted into the inner circumferential surface of an axially intermediate portion of the race fitting on its outer circumferential surface; and a cylindrical sliding member fitted into the inner circumferential surface of both ends of the race fitting in the axial direction; a pair of presser sleeves that fixedly sandwich the bushing in the axial direction of the bush; one end of each of the presser sleeves is fluid-tightly attached to the inner peripheral surface of the corresponding presser sleeve between the pair of presser sleeves and the inner cylindrical metal fitting; At the same time,
A substantially cylindrical or annular shape whose other end side is attached to the outer circumferential surface of the inner cylindrical fitting corresponding to each of the presser sleeves and seals the annular gap between each of the corresponding presser sleeves and the inner cylindrical fitting. A pair of sealing members are press-fitted into the outer circumferential surfaces of the inner cylindrical metal fittings corresponding to the respective presser sleeves, and the other end side of the sealing members is held in the direction of the axis of the bushing, and the inner cylindrical metal fittings are a pair of rigid rings fluid-tightly fixed to the outer peripheral surface; and a cylindrical elastic member disposed outside the race fitting to elastically hold the race fitting against the cylindrical member. A spherical sliding bushing assembly comprising: