JP2001027229A - Sliding bearing made of synthetic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sliding bearing made of synthetic resin, capable of maintaining smooth steering during steering operation over a long period of time without lowering a sliding characteristic caused by the entry of dust or the like by positively preventing the entry of dust or the like to a sliding surface by a sealing means, and mounting the sealing means so as not to easily fall due to vibration or the like. SOLUTION: This sliding bearing 1 made of synthetic resin is provided with a lower case 2 made of synthetic resin, an upper case 3 made of synthetic resin and placed over the lower case 2, a sliding bearing means 4 made of synthetic resin and disposed in a space 8 between the upper and lower cases 3, 2, and an elastic sealing means 11 disposed covering an outer surface 5 of the lower case 2 and closing the outside of the space 8 and inner annular openings 9, 10 between the upper and lower cases 3, 2 at both annular end parts 6, 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding bearing made of a synthetic resin, and more particularly to a sliding bearing made of a synthetic resin suitable for being incorporated in a strut type suspension (MacPherso type) of a four-wheeled vehicle.

[0002]

A strut type suspension used for a front wheel of a four-wheeled vehicle generally includes a coil spring combined with a strut assembly having a hydraulic shock absorber built in an outer cylinder integrated with a main shaft. It has a structure. In such a suspension, when the strut assembly rotates together with the coil spring in the steering operation, there are a type in which the piston rod of the strut assembly rotates, and a type in which the piston rod does not rotate. In order to smoothly allow the rotation, between the mounting member of the vehicle body and the upper spring seat of the coil spring, a sliding bearing made of synthetic resin may be used instead of the rolling ball bearing.

A plain bearing made of a synthetic resin usually has a lower case made of a synthetic resin and an upper case made of a synthetic resin superposed on the lower case, and a space between the lower case and the upper case. Is provided with a sliding bearing member or a sliding bearing projection, but when dust, muddy water, etc. enter this space,
There is a possibility that a desired bearing function cannot be obtained. On the other hand, since the strut type suspension is mounted on the part where dust, muddy water, etc. act directly while the vehicle is running, the usage environment of the sliding bearing mounted between the mounting member of the vehicle body and the upper spring seat of the coil spring is also limited. It will be extremely harsh. Therefore, if the outer peripheral side and the inner peripheral side of the space in which the sliding bearing member or the sliding bearing protrusion is arranged are directly opened to the outside, the danger of dust and muddy water from entering the space becomes extremely high, Here, the sealing performance becomes extremely important.
In particular, the above danger is further increased with synthetic resin plain bearings in which the lower and upper cases are formed by opening the inner peripheral side of the space downward to prevent the accumulation of moisture and the like in the space. .

In addition, since the sliding bearing made of a synthetic resin is mounted on an extremely vibrating part such as the front wheel of an automobile as described above, it is necessary to prevent dust and muddy water from entering the space. The sealing means for closing the opening of the space is required to be firmly attached to the opening of the space so as not to easily fall off due to vibration or the like.

The present invention has been made in view of the above-mentioned points, and it is possible to reliably prevent dust and the like from entering a sliding surface by a sealing means, and to provide a sliding characteristic caused by the entry of dust and the like. Of a synthetic resin sliding bearing that does not cause a drop in the bearing and that can be attached so that it does not easily fall off due to vibration or the like, and that can maintain smooth steering during the steering operation for a long period of time. The purpose is to obtain.

[0006]

According to a first aspect of the present invention, there is provided a sliding bearing made of synthetic resin, comprising: a lower case made of synthetic resin; an upper case made of synthetic resin stacked on the lower case;
A sliding bearing means made of a synthetic resin disposed between the upper and lower cases, and disposed to cover an outer surface of the lower case, and outer and inner annular openings of a space between the lower and upper cases at both annular ends. Closed elastic sealing means.

According to the sliding bearing of the first aspect, the elastic sealing means for closing the outer and inner annular openings of the space between the upper and lower cases at both annular ends is provided so as to cover the outer peripheral surface of the lower case. Therefore, when the slide bearing is mounted between the mounting member of the vehicle body and the upper spring seat of the coil spring, the elastic sealing means is firmly fixed to the upper spring seat or the washer installed on the upper spring seat. As a result, the elastic sealing means can be reliably prevented from falling off, and
By the elastic sealing means, it is possible to reliably prevent dust or the like from entering the sliding surface, so that the sliding characteristics do not deteriorate due to the dust or the like from entering. Smooth steering can be maintained for a long time.

[0008] In the sliding bearing made of synthetic resin according to the second aspect of the present invention, in the sliding bearing according to the first aspect, the lower case includes a cylindrical portion having a cylindrical inner peripheral surface, and one end of the cylindrical portion. A first annular plate part integrally formed with the part,
The upper case has an inner peripheral surface and an outer peripheral surface that are concentric with the inner peripheral surface of the cylindrical portion of the lower case, and is integrated with an inner cylindrical portion disposed inside the cylindrical portion of the lower case and one end of the inner cylindrical portion. The second annular plate portion formed integrally and the annular outer peripheral end portion of the second annular plate portion are integrally formed, and the inner peripheral surface concentric with the inner peripheral surface of the cylindrical portion of the lower case is formed. An outer cylindrical portion having an outer peripheral surface of the cylindrical portion of the lower case, an annular end surface connected to the outer peripheral surface, an annular outer surface of the first annular plate portion, and the annular outer surface. A main body portion covering an annular end surface connected to the main body portion, an outer elastic lip portion formed integrally with an outer end portion of the main body portion to close the outer annular opening, and an inner end portion of the main body portion integrally formed. Is formed,
And an inner elastic lip for closing the inner annular opening.

According to the sliding bearing of the second aspect, the inner and outer ends of the main body covering the outer peripheral surface and the annular end surface of the cylindrical portion of the lower case and the annular outer surface and the annular end surface of the first annular plate portion. Since the inner and outer elastic lip portions are formed on the inner and outer cylindrical portions of the upper case, the inner and outer elastic lip portions substantially seal the outer and inner annular openings. I can do it completely.

In the sliding bearing made of synthetic resin according to the third aspect of the present invention, in the sliding bearing according to the second aspect, the sliding bearing means comprises a first annular plate portion of the lower case and a second annular plate of the upper case. A thrust slide bearing disposed between the plate portion and a radial slide bearing disposed between a cylindrical portion of the lower case and an inner cylindrical portion of the upper case.

In the sliding bearing according to the third aspect, the thrust sliding bearing may be formed integrally with at least one of the first annular plate portion and the second annular plate portion. May be formed separately with respect to at least one of them, and the radial sliding bearing may also be formed integrally with at least one of the cylindrical portion and the inner cylindrical portion,
Alternatively, at least one of them may be formed separately.

In the sliding bearing made of a synthetic resin according to a fourth aspect of the present invention, in the sliding bearing according to the second or third aspect, the outer elastic lip portion has an annular outer end at an outer cylindrical end of the upper case. The inner elastic lip portion is elastically in contact with the inner cylindrical portion of the upper case at its annular inner end.

According to a fifth aspect of the present invention, in the sliding bearing made of a synthetic resin, in the sliding bearing according to any one of the second to fourth aspects, the main body of the elastic sealing means includes a cored member. Each of the outer and inner elastic lips of the elastic sealing means is made of an elastic material.

According to a sixth aspect of the present invention, there is provided the sliding bearing of the fifth aspect, wherein the core metal member comprises:
Each of the outer and inner elastic lip portions extends over the outer peripheral surface and the annular end surface of the cylindrical portion of the lower case and the annular outer surface and the annular end surface of the first annular plate portion and is covered with an elastic material. Extends from the elastic material covering the core member and is integrated with the elastic material.

In the sliding bearing according to a fifth aspect of the present invention, the elastic sealing means includes a core metal member, and the outer and inner elastic lips are made of an elastic material. Since the core metal member covering the outer surface is covered with an elastic material, and each of the outer and inner elastic lip portions is made of an elastic material integrally extended from the elastic material covering the core metal member, the elastic sealing means is required. It can be arranged without hanging on the outer surface of the lower case, and the outer and inner elastic lips made of elastic material can almost completely seal the outer and inner annular openings. As the elastic material, a rubber elastic body such as natural rubber or synthetic rubber or a plastic elastomer such as polyester or polyurethane is used.

In the present invention, even if the sliding bearing means is integrally formed and provided on at least one of the lower case and the upper case as in the sliding bearing of the seventh aspect, the sliding bearing means of the eighth aspect is provided. As described above, it may be provided separately from the lower case and the upper case. Here, when the slide bearing means is composed of a thrust slide bearing and a radial slide bearing, the third embodiment As described above, these may also be provided integrally with or formed separately from at least one of the lower case and the upper case. Further, the sliding bearing means includes:
As in the slide bearing of the ninth aspect, a grease reservoir may be formed. If grease is disposed in the grease reservoir and used, further smooth steering during steering operation can be obtained over a long period of time. .

The synthetic resin constituting the upper and lower cases according to the present invention preferably has excellent sliding and mechanical properties such as wear resistance, impact resistance and creep resistance. The synthetic resin constituting the sliding bearing means disposed therebetween preferably has a self-lubricating property, for example, a polyacetal resin, a polyamide resin,
Polyester resins such as polybutylene terephthalate (PBT) and polyolefin resins such as polyethylene and polypropylene are preferably used, and polycarbonate resins and the like can also be used.

For the upper and lower cases, the same synthetic resin as the synthetic resin constituting the sliding bearing means can be used.
In particular, it is desirable that the synthetic resin used in the sliding bearing means be a combination of a synthetic resin having a good friction characteristic and a relatively high rigidity. To illustrate the preferred combination, for the plain bearing means and the upper and lower cases, a combination of polyacetal and polyamide,
There are combinations of polyethylene and polyacetal, combinations of polyacetal and PBT, and combinations of polyacetal and polyacetal.

In addition, at least one of the outer and inner annular openings is further provided with a labyrinth sealing means, and the labyrinth sealing means and the elastic sealing means cooperate to further improve the sealing performance of at least one of the outer peripheral side and the inner peripheral side. May be improved.

Next, the present invention will be described in more detail based on an example of a preferred embodiment shown in the drawings. The present invention is not limited to these examples.

[0021]

1 to 4, a sliding bearing 1 made of synthetic resin of this embodiment comprises a lower case 2 made of synthetic resin, an upper case 3 made of synthetic resin stacked on the lower case 2, and an upper case 3 made of synthetic resin. And a sliding bearing means 4 made of synthetic resin disposed in a space 8 between the lower cases 2 and 3, and disposed so as to cover the outer surface 5 of the lower case 2. Elastic seal means 11 which closes the outer and inner annular openings 9 and 10 of the space 8 between the cases 2 and 3.

The lower case 2 includes a cylindrical portion 16 having a cylindrical inner peripheral surface 15 and an annular plate portion 17 integrally formed at one end of the cylindrical portion 16.

The upper case 3 is provided with a cylindrical portion 16 of the lower case 2.
The inner cylindrical portion 2 having an inner peripheral surface 22 and an outer peripheral surface 23 concentric with the inner peripheral surface 15 of the lower case 2 and disposed in the cylindrical portion 16 of the lower case 2.
4, an annular plate portion 25 integrally formed at one end of the inner cylindrical portion 24, and an inner peripheral portion of the cylindrical portion 16 of the lower case 2 integrally formed at an annular outer peripheral portion of the annular plate portion 25. An outer cylindrical portion 27 having an inner peripheral surface 26 concentric with the surface 15, and an annular protrusion 28 integrally formed so as to protrude radially inward on the inner peripheral surface 26 of the outer cylindrical portion 27. .

The inner cylindrical portion 24 includes a thick cylindrical portion 31 and a thin cylindrical portion 32, and the outer peripheral surface 23 has a thick cylindrical portion 31.
And the outer peripheral surface 34 of the thin cylindrical portion 32. The inner peripheral surface 22 of the inner cylindrical portion 24 defines an insertion hole 37 into which the piston rod 36 of the strut assembly shown in FIG. 5 is inserted.

The sliding bearing means 4 is disposed between the annular plate portion 17 of the lower case 2 and the annular plate portion 25 of the upper case 3 and protrudes axially on the annular inner surface 41 of the annular plate portion 17. An annular thrust slide bearing 42 formed integrally,
The cylindrical portion 16 of the lower case 2 and the inner cylindrical portion 2 of the upper case 3
4 and a cylindrical radial slide bearing 44 integrally formed so as to protrude inward in the radial direction on the inner peripheral surface 15 of the cylindrical portion 16. The projecting annular surface 45 slidably contacts one annular side surface (annular inner surface) 46 of the annular plate portion 25, and the cylindrical projecting cylindrical surface 47 of the radial sliding bearing 44.
Is slidably in contact with the cylindrical outer peripheral surface 33 of the thick cylindrical portion 31.

In the sliding bearing means 4, the projecting annular surface 45
A plurality of grooves 48 as grease reservoirs extending in the radial direction are formed on the protruding cylindrical surface 47, and a plurality of grooves 49 as grease reservoirs extending in the axial direction are formed at equal intervals in the angular direction. I have.

The elastic sealing means 11 is connected to the cylindrical outer peripheral surface 51 of the cylindrical portion 16 of the lower case 2 and the annular end surface 52 connected to the outer peripheral surface 51 and the annular outer surface 53 and the annular outer surface 53 of the annular plate portion 17. A main body 55 covering the annular end face 54 and the main body 55 so as to close the outer annular opening 9.
The outer end 56 is bent back from the annular outer end 56 to gradually expand and extend, and a tip 57 which is an annular outer end is elastically in contact with the inner peripheral surface 26 of the outer cylindrical portion 27. 5
5 so as to close the annular outer elastic lip 58 and the inner annular opening 10 which are formed integrally with the outer end 56 of the main body 55 and constitute the annular end 6.
The distal end 60 which is folded back from the annular inner one end 59 of the main body 55 and gradually reduces in diameter and extends, is an annular inner one end.
Is elastically in contact with the outer peripheral surface 34 of the thin cylindrical portion 32, is coaxial with the main body 55, and is formed integrally with the inner one end 59 of the main body 55 to form the annular end 7. And an annular inner elastic lip portion 61.

In the elastic sealing means 11, the main body 55
Has a core member 65 and an elastic member 66 made of rubber or plastic elastomer. The outer and inner elastic lip portions 58 and 61 are made of an elastic member made of rubber or plastic elastomer.
5 is the outer surface 5 of the cylindrical portion 16 which is the outer surface 5 of the lower case 2
1 and the annular end surface 52 and the annular outer surface 5 of the annular plate portion 17
3 and is extended over and in contact with the annular end surface 54 and is covered with an elastic material 66. The elastic material of the outer and inner elastic lips 58 and 61 is the elastic material 66 covering the core metal member 66. And is integrated with the elastic member 66. Each of the outer and inner elastic lip portions 58 and 61 is formed so as to become thicker toward the tip.

As shown in FIG. 5, the sliding bearing 1 made of a synthetic resin allows the piston rod 36 of the shock absorber in the strut assembly to pass through the insertion hole 37, and the upper surface 71 of the upper case 3 One end of the elastic seal means 11 is brought into close contact with a mounting member 72 on the vehicle body side to which one end is mounted, and the cylindrical outer surface 73 and the annular outer surface 74 of the elastic sealing means 11 are fitted to the upper spring seat 76 of the coil spring 75 in the strut assembly via the washer 77. And is used by being mounted between the mounting member 72 and the upper spring seat 76.

When the strut assembly is rotated by the steering operation, the lower case 2 is rotated with respect to the upper case 3, and this rotation of the lower case 2 is caused by a thrust slide disposed between the upper and lower cases 3 and 2. Bearing 42
And the radial sliding bearings 44 make the steering operation smoother, so that the steering operation is also performed without any resistance. Further, dust and the like enter the space 8 between the upper and lower cases 3 and 2 through the outer and inner annular openings 9 and 10 by the outer elastic lip 58 on the outer peripheral side and the inner elastic lip 61 on the inner peripheral side. And the thrust sliding bearing 4
Intrusion of dust or the like between the projecting annular surface 45 and the side surface 46 and between the projecting cylindrical surface 47 and the outer peripheral surface 33 between the sliding surfaces of the radial sliding bearing 44 and the sliding bearing 44 is reliably prevented.

That is, according to the sliding bearing 1 made of synthetic resin, the elastic seals for closing the outer and inner annular openings 9 and 10 of the space 8 between the upper and lower cases 3 and 2 at both annular ends 6 and 7. Since the means 11 is disposed so as to cover the outer peripheral surface 51, the annular end surface 52, the annular outer surface 53, and the annular end surface 54, which are the outer surfaces 5 of the lower case 2, the sliding bearing 1 is provided between the mounting member 72 of the vehicle body and the coil spring 75. Upper spring seat 7
6, the elastic seal means 11 is firmly fixed to the upper spring seat 76 or the washer 77 provided on the upper spring seat 76, so that the elastic seal means 11 is securely prevented from falling off. In addition, the sealing means 11 ensures that dust and the like enter between the projecting annular surface 45 and the side surface 46 and between the projecting cylindrical surface 47 and the outer peripheral surface 33 of the thrust slide bearing 42 and the radial slide bearing 44. Therefore, it is possible to prevent the sliding characteristics from being degraded due to the intrusion of dust and the like, and to maintain smooth steering during the steering operation for a long time.

According to the slide bearing 1, the inner and outer ends 59 and 59 of the main body 55 covering the outer peripheral surface 51 and the annular end surface 52 of the cylindrical portion 16 and the annular outer surface 53 and the annular end surface 54 of the annular plate portion 17 are provided. Due to the formation of the annular inner and outer elastic lips 61 and 58 in 56, the inner and outer elastic lips 61 and 58 are elastically contacted with the inner and outer cylindrical portions 24 and 27 of the upper case 3. , The inner and outer annular openings 10 and 9 can be almost completely sealed.

In addition, in the sliding bearing 1, the elastic sealing means 1
1 includes a core member 65, outer and inner elastic lips 58 and 61 are made of an elastic material, and an outer surface 5 of the lower case 2 is provided.
Is covered with an elastic material 66, and the outer and inner elastic lips 58 and 61 are made of an elastic material integrally extended from the elastic material 66 covering the core metal member 65. The elastic sealing means 11 is attached to the outer surface 5 of the lower case 2.
The seal can be almost completely achieved with the outer and inner elastic lips 58 and 61 made of elastic material. Further, in the slide bearing 1, since the grooves 48 and 49 as the grease reservoir are formed, if grease is arranged in the grooves 48 and 49, further smooth steering at the time of steering operation can be obtained for a long time. be able to.

By the way, in the above-described sliding bearing 1, the sliding bearing means 4 is formed integrally with the lower case 2, but instead of this, the sliding bearing means 4 is formed as shown in FIGS. It may be formed separately from the upper case 3. That is, the sliding bearing 1 shown in FIGS. 6 and 7 includes the sliding bearing means 4 formed separately from the lower case 2 and the upper case 3, and the bearing means 4 made of synthetic resin.
Is an annular thrust slide bearing 81 serving as a thrust slide bearing, and a cylindrical radial slide bearing 8 serving as a radial slide bearing formed integrally with the thrust slide bearing 81.
2, a plurality of grooves 84 similar to the grooves 46 are formed on one annular side surface 83 of the thrust slide bearing portion 81.
An annular groove 85 communicating with one end of the groove 84 is formed, and the other annular side surface 8 of the thrust slide bearing portion 81 is formed.
6, a similar groove 84 and an annular groove 85 communicating one end of the groove 84 with each other are formed. On the inner and outer peripheral surfaces 87 and 88 of the radial sliding bearing portion 82, a plurality of grooves similar to the groove 49 are formed. Grooves 89 and 90 are formed, and the sliding bearing means 4
Is that the side surface 83 of the thrust slide bearing portion 81 is
The side surface 86 of the thrust slide bearing portion 81 comes into contact with the annular inner side surface 41 of the annular plate portion 17 so as to be slidable, respectively, and the inner peripheral surface 87 of the radial slide bearing portion 82 has a thick cylindrical portion. A space between the lower case 2 and the upper case 3 is brought into contact with the outer peripheral surface 33 of the lower case 2 so that the outer peripheral surface 88 of the radial sliding bearing portion 82 is slidable on the inner peripheral surface 15 of the cylindrical portion 16. 8 are arranged.

Slide bearing means 4 as shown in FIGS. 6 and 7
The same effects as those of the sliding bearing 1 shown in FIGS.

[0036]

According to the present invention, the sealing means
It is possible to reliably prevent dust and the like from entering the sliding surface, so that the sliding characteristics are not deteriorated due to the dust and the like, and that the sealing means is not easily dropped due to vibration or the like. It is possible to provide a sliding bearing made of synthetic resin that can be mounted and that can maintain smooth steering during steering operation for a long period of time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a preferred embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of the example shown in FIG.

FIG. 3 is an enlarged sectional view of the elastic sealing means of the example shown in FIG.

FIG. 4 is a perspective view of the lower case and the sliding bearing means of the example shown in FIG. 1;

FIG. 5 is a sectional view of an example in which the example shown in FIG. 1 is used for a strut assembly.

FIG. 6 is a sectional view of another example of the preferred embodiment of the present invention.

FIG. 7 is a perspective view of the sliding bearing means shown in FIG. 6;

[Explanation of symbols]

 Reference Signs List 1 sliding bearing made of synthetic resin 2 lower case 3 upper case 4 sliding bearing means 8 space 9 outer annular opening 10 inner annular opening 11 elastic sealing means

Claims (9)

[Claims] 1. A synthetic resin lower case, a synthetic resin upper case stacked on the lower case, a synthetic resin sliding bearing means disposed between the upper and lower cases,
A sliding bearing made of synthetic resin, comprising: an elastic sealing means disposed over an outer surface of the lower case and closing outer and inner annular openings of a space between the lower and upper cases at both annular ends. The lower case includes a cylindrical portion having a cylindrical inner peripheral surface, and a first annular plate integrally formed at one end of the cylindrical portion. Having an inner peripheral surface and an outer peripheral surface concentric with the inner peripheral surface of the cylindrical portion of the lower case, and integrally formed on an inner cylindrical portion disposed in the cylindrical portion of the lower case and one end of the inner cylindrical portion. A second annular plate portion, and an outer surface having an inner peripheral surface formed integrally with the annular outer peripheral end portion of the second annular plate portion and concentric with the inner peripheral surface of the cylindrical portion of the lower case. A cylindrical portion, and the elastic sealing means is connected to the outer peripheral surface of the cylindrical portion of the lower case, the annular end surface connected to the outer peripheral surface, the annular outer surface of the first annular plate portion, and the annular outer surface. A main body covering the annular end face, and an outer elastic body formed integrally with the outer end of the main body to close the outer annular opening; The sliding bearing made of synthetic resin according to claim 1, comprising: a lip portion; and an inner elastic lip portion integrally formed at one inner end portion of the main body portion and closing the inner annular opening. 3. The sliding bearing means comprises: a thrust sliding bearing disposed between the first annular plate of the lower case and the second annular plate of the upper case; The sliding bearing made of a synthetic resin according to claim 2, further comprising: a radial sliding bearing disposed between the sliding bearing and the inner cylindrical portion. 4. The outer elastic lip portion elastically contacts the outer cylindrical portion of the upper case at one of its annular outer ends, and the inner elastic lip portion of the upper case at its annular inner one end. The synthetic resin sliding bearing according to claim 2 or 3, wherein the sliding bearing is elastically in contact with the inner cylindrical portion. 5. The elastic sealing means according to claim 2, wherein the main body portion includes a core metal member, and each of the outer and inner elastic lip portions is made of an elastic material. Plain bearing made of synthetic resin. 6. The mandrel member extends over the outer peripheral surface and the annular end surface of the cylindrical portion of the lower case and the annular outer surface and the annular end surface of the first annular plate portion, and is covered with an elastic material. The synthetic resin sliding bearing according to claim 5, wherein each of the elastic members of the inner elastic lip portion extends from the elastic member covering the core metal member and is integrated with the elastic member. 7. The synthetic resin sliding bearing according to claim 1, wherein the sliding bearing means is formed integrally with at least one of the lower case and the upper case. 8. The synthetic resin sliding bearing according to claim 1, wherein the sliding bearing means is formed separately from the lower case and the upper case. 9. The synthetic resin sliding bearing according to claim 1, wherein a grease reservoir is formed in the sliding bearing means.