JPH07301226A - Synthetic resin thrust bearing - Google Patents

Abstract

PURPOSE:To provide such a synthetic resin thrust bearing, arranged between two relatively rotated objects, as being capable of permitting the smooth relative rotation of two objects without causing the variation of friction. CONSTITUTION:A synthetic resin thrust bearing consists of a synthetic resin upper bearing case 300, a synthetic resin lower bearing case 200 and a bearing body 400 formed of synthetic resin showing good friction property in combination with synthetic resin for the lower bearing case. The bearing body has the upper and lower faces put in slide contact with annularly recessed grooves 304, 205 in the upper and lower bearing cases, respectively. The upper bearing case has the labyrinth seal portions formed on the elastically mounting and folding portions with the lower bearing case, respectively, and the annularly tapered portion 309 combined with the lower bearing case to encircle the outer periphery of the lower bearing case.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin thrust bearing, which is disposed between two objects that rotate relative to each other and allows the rotation smoothly, more specifically, a strut type suspension (McFerson type) of a four-wheeled vehicle. The present invention relates to a synthetic resin thrust bearing suitable for being incorporated into

[0002]

2. Description of the Related Art Generally, strut suspensions are
This suspension is mainly used for the front wheels of four-wheeled vehicles, and is a suspension that combines a coil spring with a strut assembly that has a hydraulic shock absorber built into an outer cylinder that is integrated with the main shaft. In the suspension, when the strut assembly rotates together with the coil spring by steering operation, there are a type in which the piston rod of the assembly rotates and a type in which the piston rod does not rotate. A bearing is required between the mounting member of the vehicle body and the upper spring seat of the coil spring to allow for a smooth allowance. Conventionally, a rolling bearing using a ball or a needle or a sliding bearing made of synthetic resin has been used as a bearing at this location.

However, in a conventional synthetic resin slide bearing, a dust seal made of a rubber elastic body is attached to the outer peripheral surface of the slide bearing in order to prevent dust and the like from entering the sliding surface. However, since this dust seal is arranged in close contact with the rotating sliding surface, there is a drawback that the sliding frictional force is high during steering operation and the steering force is increased. In order to solve the above-mentioned drawbacks of the synthetic resin slide bearings in the prior art, the present applicant has previously filed Japanese Utility Model Application No. 61-196804 (Japanese Utility Model Publication No. 2-6263, hereinafter referred to as “Prior Art 1”) and Japanese Patent Application No. -16171 (Actual Kaihei No. 2-107823: hereinafter referred to as "Prior Art 2")
Proposed a synthetic resin thrust bearing capable of preventing dust and the like from entering the sliding surface without using a dust seal made of a rubber elastic body and preventing an increase in steering force during steering operation. FIG. 6 is a vertical sectional view showing a synthetic resin thrust bearing of Prior Art 1. The synthetic resin thrust bearing 1 of the prior art 1 includes an upper bearing case 3 made of synthetic resin, a lower bearing case 2 made of synthetic resin, and a synthetic resin bearing body 4 arranged in the upper and lower bearing cases. And the end portions of the inner annular hanging portion 33 and the outer annular hanging portion 34 formed on the lower surface of the upper bearing case are respectively connected to the first annular protruding portion 23 and the second annular protruding portion of the lower bearing case. 25 and the engaging hook portion 37 of the upper bearing case is elastically attached to the engaging portion 28 of the lower bearing case, and the labyrinth is attached to the elastic attaching portion and each engaging portion. They are combined by forming a sealed portion by action.

FIG. 7 is a vertical sectional view showing a synthetic resin thrust bearing of Prior Art 2. The synthetic resin thrust bearing 1 of the prior art 2 includes an upper bearing case 3 made of synthetic resin, a lower bearing case 2 made of synthetic resin, and a synthetic resin bearing body 4 arranged in the upper and lower bearing cases. And the end portions of the inner annular hanging portion 33, the annular protruding portion 38, and the outer annular hanging portion 34 formed on the lower surface of the upper bearing case are respectively connected to the first annular protruding portion 23 of the lower bearing case 2. And annular protrusion 29
And the upper bearing case 3 is elastically attached to the outer peripheral surface of the lower bearing case 2 while engaging with the end of the second annular projection 25, and the labyrinth is attached to the elastic attachment and the respective engaging portions. They are combined by forming a sealed portion by action.

[0005]

SUMMARY OF THE INVENTION The synthetic resin thrust bearing according to the prior art described above prevents an increase in steering force during steering operation, which is a drawback of conventional synthetic resin slide bearings, and seals by a labyrinth action. It was possible to prevent dust and the like from entering the sliding surface by means of the portion, and to maintain a smooth steering force for a long period of time. However, the strut-type suspension in which the thrust bearing is incorporated is a portion to which dust, muddy water and the like directly act while the vehicle is traveling, and it is a very severe condition as a usage environment of the thrust bearing incorporated in the portion. In the synthetic resin thrust bearing of the above-mentioned prior art, sealing means by a labyrinth action is formed on the inner and outer peripheral surfaces, respectively, and the sealing means prevents dust and the like from entering the bearing sliding surface.
When used under the harsh environmental conditions mentioned above, it cannot be said that it is a sufficient sealing means against the intrusion of dust, especially muddy water, into the sliding surface, and often infiltration of muddy water affects the sliding characteristics. The problem was newly raised. It is an object of the present invention to obtain a synthetic resin thrust bearing capable of preventing the intrusion of dust, muddy water, etc. even when used under harsh environmental conditions and maintaining a smooth steering force during steering operation for a long period of time. Is.

[0006]

According to the present invention, the above object is to provide a disc-shaped portion 202 having an insertion hole 201 in the center and an annular flat portion 203 connected to the insertion hole on the upper surface of the disc-shaped portion. The first annular projection 2 which is provided so as to project concentrically with the insertion hole.
04 and the first annular projection portion at a distance from each other outwardly in the radial direction to form a wide annular concave groove 205 between the outer peripheral surface of the first annular projection portion and the upper surface of the disk-shaped portion. Two annular protrusions 20
6 and an annular engaging protrusion 2 protruding from the outer peripheral edge of the disc-shaped portion
08 and the engaging portion 2 formed on the outer peripheral surface of the annular engaging protrusion.
09, a synthetic resin lower bearing case 200, a disk-shaped portion 302 having a through hole 301 having the same diameter as the through hole in the central portion, and a lower surface of the disk portion communicating with the through hole. The inner annular hanging portion 303 and the inner annular hanging portion are hung radially outward from the inner annular hanging portion with a space therebetween, and a wide annular concave groove 304 is formed by the outer peripheral surface of the inner annular hanging portion and the lower surface of the disk-shaped portion. Outer ring hanging part 3
05 and an annular engaging hanging portion 3 that hangs on the outer peripheral surface of the disk-shaped portion
07, the engaging hook portion 308 formed on the inner peripheral surface of the annular engaging hanging portion, and the outer peripheral surface of the disk-shaped portion. The outer peripheral surface of the annular engaging hanging portion extends downward from the upper end portion. A thin annular taper portion 309 which is vertically extended so as to surround the
An upper bearing case 300 made of synthetic resin, which is provided with: a synthetic resin bearing body 4 made of a disc having a circular hole 401 in the central portion.
00, and the lower surface of the bearing body 400 is slidably contacted with the bottom surface of the annular groove 205 of the lower bearing case 200, and the bearing body 400 is arranged in the annular groove. The bottom surface of the groove 304 is brought into sliding contact with the upper surface of the bearing body, and the ends of the inner annular hanging portion 303 and the outer annular hanging portion 305 are respectively provided with the first annular protruding portion 204 and the second annular protruding portion of the lower bearing case. The engaging hook portion 3 of the annular engaging hanging portion 307 is engaged with the end portion of the portion 206 so as to overlap with the end portion in the radial direction.
08 is elastically attached to the engaging portion 209 on the outer peripheral surface of the annular engaging protrusion of the lower bearing case, and the elastic attaching portion, the inner annular hanging portion 303, the first annular protruding portion 204, and the outer annular hanging portion 30.
5 and the second annular protruding portion 206 are formed with a sealing portion by a labyrinth action at the overlapping portion and the upper bearing case.
The annular taper portion of the shoe is achieved by a synthetic resin thrust bearing characterized in that the annular taper portion surrounds the outer peripheral surface of the lower bearing case and is combined with the lower bearing case.

In the synthetic resin thrust bearing having the above-mentioned structure, the wide annular concave groove of the lower bearing case has an annular groove 210 formed by the outer peripheral surface of the first annular protrusion and the bottom surface of the concave groove.
An annular projection portion 211 is formed so as to define and protrude. An annular groove 310 is defined in the wide annular concave groove of the upper bearing case by the outer peripheral surface of the inner annular hanging portion and the bottom surface of the concave groove. An annular hanging portion 311 is formed so as to hang down, and the annular hanging portion is combined with the end portion of the annular protruding portion in the radial direction so as to overlap with the end portion of the annular protruding portion. It is also possible to adopt a configuration in which the sealed portion is formed.

In the above-mentioned synthetic resin thrust bearing, the upper bearing case is brought into contact with the vehicle body side mounting member, and the lower bearing case is attached.
The upper spring seat seat, and the end of the annular taper portion of the upper bearing case is brought into close sliding contact with the upper surface of the upper spring seat seat to form a sliding contact portion. A seal portion is formed in the strut assembly and is used by being assembled between the upper spring seat of the strut of the strut assembly and the vehicle body side mounting member.

In the synthetic resin thrust bearing having the above-mentioned structure, the synthetic resin forming the upper and lower bearing cases has excellent mechanical properties such as wear resistance, impact resistance and creep resistance. The synthetic resin bearing body housed between the upper and lower bearing cases preferably has a self-lubricating property, such as polyacetal resin, polyamide resin, polybutylene terephthalate resin. A thermoplastic polyester resin such as the above, a polyolefin resin such as a polyethylene resin and a polypropylene resin, and the like are preferably used, and a polycarbonate resin and the like can also be used. Up,
The lower bearing case is made of the same synthetic resin as that used for the bearing body, but is a combination of the synthetic resin used for the bearing body and a good friction characteristic, and has a relatively high rigidity. A resin material is desirable.

[0010]

According to the synthetic resin thrust bearing having the above-mentioned structure, the sliding surface between the synthetic resin bearing body and the synthetic resin upper and lower bearing cases is formed between the upper and lower bearing cases. The end portion of the annular taper portion formed on the upper bearing case is protected by the sealing portion due to the action, and the end portion of the annular taper portion closely slides on the upper surface of the upper spring seat sheet, and the sealing portion is on the sliding contact portion. Since this is formed, invasion of dust, muddy water, etc. to the sliding surface is prevented. When relative rotation occurs in the upper and lower bearing cases, the rotation is a sliding contact surface between the bottom surface of the annular groove of the lower bearing case and the lower surface of the synthetic resin bearing body arranged in the annular groove. Alternatively, it is allowed on the side of the sliding contact between the upper surface of the bearing body and the bottom surface of the annular groove of the upper bearing case, whichever has the lower frictional resistance.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings showing its embodiments. 1 to 3 show a preferred embodiment of the present invention. In FIG. 1, synthetic resin thrust bearing 1
00 is composed of a synthetic resin lower bearing case 200, a synthetic resin upper bearing case 300, and a synthetic resin bearing body 400.

The lower bearing case 200 made of synthetic resin has a disc-shaped portion 202 having an insertion hole 201 in the center and an annular flat portion 203 connected to the insertion hole on the upper surface of the disc-shaped portion. A first annular protrusion 204 that is provided concentrically with the hole, and a first annular protrusion that is provided radially outward of the first annular protrusion 204 at a distance from the first annular protrusion;
A second annular protrusion 206 that forms a wide annular groove 205 between the outer peripheral surface of the first annular protrusion and the upper surface of the disc-shaped portion, and the second annular protrusion protruding from the outer peripheral edge of the disc-shaped portion. An annular engaging protrusion 208 that forms an annular engaging groove 207 between the outer peripheral surface of the protrusion and the upper surface of the disc-shaped portion, and an engaging portion 209 formed on the outer peripheral surface of the annular engaging protrusion. ing. A protrusion 212 is formed on the lower surface of the disk-shaped portion 202 so as to face each other in the radial direction, and the protrusion plays a role of positioning when the synthetic resin thrust bearing 100, which will be described later, is assembled and fixed to the strut assembly A. . An engaging portion 209 formed on the outer peripheral surface of the annular engaging protruding portion 208 is a taper surface portion that extends outward from the outer peripheral upper end portion of the annular engaging protruding portion 208, and the taper surface portion.
The disk-shaped portion 20 is continuous with the par surface portion and converges inward.
2 and a taper surface portion connected to the outer peripheral cylindrical surface.

The upper bearing case 300 made of synthetic resin has a disk-shaped portion 302 having an insertion hole 301 having the same diameter as the insertion hole at the center and an inner surface communicating with the insertion hole at the lower surface of the disk-shaped portion. An annular hanging portion 303 and an inner hanging portion that hang radially outwardly with a space therebetween, and an outer circumferential groove of the inner annular hanging portion and a lower surface of the disk-shaped portion form a wide annular groove 304. Circular hanging part 30
5 and the outer peripheral surface of the disk-shaped portion, and the outer annular hanging portion 30.
5, an annular engaging hanging portion 307 that forms an annular engaging groove 306 between the outer peripheral surface of 5 and the lower surface of the disk-shaped portion, an engaging hook portion 308 formed on the inner peripheral surface of the annular engaging hanging portion, and the disc. A thin annular taper portion 309 is provided on the upper end portion of the outer peripheral surface of the groove portion, the thin annular taper portion 309 extending downward from the upper end portion so as to surround the outer peripheral surface of the annular engaging hanging portion. I have it. An engaging hook portion 308 formed on the inner peripheral surface of the annular engaging hanging portion 307 is a taper extending outward from the outer upper end of the annular engaging groove 306.
It comprises a taper surface portion, a taper surface portion which is continuous with the taper surface portion and converges inward, and a cylindrical surface portion which is continuous with the taper surface portion. The end of the annular taper portion 309 slightly protrudes from the lower surface of the disc-shaped portion 202 of the lower bearing case 200 when the upper and lower bearing cases are combined. The circular tape
The amount of protrusion of the par portion from the lower surface of the disk-shaped portion serves as a bending allowance for making a close slidable contact with the upper surface of the upper spring seat sheet when assembled in a strut assembly A described later.

The bearing 400 made of synthetic resin has a circular hole 4 in the center.
01 has a larger inner diameter than the outer diameter of the first annular protrusion 204 of the lower bearing case 200 and an outer diameter smaller than the inner diameter of the second annular protrusion 206 of the lower bearing case 200. On the upper and lower surfaces of the synthetic resin bearing body 400, a plurality of grooves 402 penetrating from the peripheral edge of the circular hole 401 to the outer peripheral surface are formed at equal intervals in the circumferential direction. The groove 402 serves as a reservoir for lubricant such as grease. The groove 402 formed on the upper surface of the bearing body 400 and the groove 402 formed on the lower surface are formed with a phase difference in the circumferential direction.

The bearing body 400 having the above structure is disposed in the annular groove by sliding the lower surface thereof to the bottom surface of the annular groove 205 of the lower bearing case 200, and the upper bearing case 300 is arranged in the annular groove. The bottom surface of the groove 304 is brought into sliding contact with the upper surface of the bearing body 400, and the end portion of the inner annular hanging portion 303 and the outer annular hanging portion 30 are slid.
The end portion of 5 is the first annular protrusion 2 of the lower bearing case 200.
04 and the end of the second annular projection 206 are overlapped with each other in the radial direction and engaged, and the engaging hook portion 308 of the annular engaging hanging portion is engaged with the annular engaging protrusion of the lower bearing case. Elastically mounted on the engaging portion 209 on the outer peripheral surface of the portion, and the elastic mounting portion, the inner annular hanging portion 303 and the first annular protruding portion 204.
Further, a sealing portion is formed by a labyrinth action in the overlapping portion of each of the outer annular hanging portion 305 and the second annular protruding portion 206, and the annular taper portion 309 of the upper bearing case is an outer periphery of the lower bearing case. A synthetic resin thrust bearing 100 that surrounds a surface and is rotatably combined with the lower bearing case.
Is configured.

FIG. 3 shows a state in which the synthetic resin thrust bearing 100 having the above-described structure is incorporated in the strut assembly A. The synthetic resin lower bearing case 2
00 of the disk-shaped portion 202 and the insertion hole 30 of the inner annular hanging portion 303 of the synthetic resin upper bearing case 300.
1 and 2 are inserted into the outer peripheral surface of the piston rod 600 arranged through the through hole 702 formed in the center of the plane portion 701 of the upper spring seat 700 of the strut 500, and the lower bearing case 200 of the lower bearing case 200 is inserted. The protrusions 210 formed on the lower surface of the disk-shaped portion 202 so as to face each other are fitted into the holes 703 formed in the flat portion 701 of the upper spring seat 700. The lower surface of the disk-shaped portion 202 of the lower bearing case 200 is attached to the upper spring seat sheath.
Of the upper bearing case 300, the upper surface of the upper bearing case 300 is brought into contact with the vehicle body side mounting member 800, and the end of the annular taper portion 309 of the upper bearing case 300 is brought into contact with the flat portion 701. The synthetic resin thrust bearing 100 is arranged between the upper spring seat 700 and the vehicle body side mounting member 800 so as to be in close contact with the flat surface portion 701 of the upper spring seat 700. In the strut assembly A incorporating the synthetic resin thrust bearing 100 as described above, when relative rotation occurs between the vehicle body side mounting member 800 and the upper spring seat 700 by steering operation, the lower bearing case 200 and the upper bearing case 300, the lower bearing case 200 and the synthetic resin bearing body 400 via the synthetic resin bearing body 400.
The sliding contact surface of the upper bearing case 300 or the sliding contact surface of the synthetic resin bearing body 400, whichever has a smaller friction coefficient, rotates relatively to obtain a smooth steering force.

The upper bearing case 300 and the lower bearing case
The bearing sliding surface formed between the spaces 200 is composed of the sealing portion formed at the close contact portion between the annular taper portion 309 and the upper spring seat, the engaging hook portion 308, and the engaging portion 209. By the elastic mounting portion, the overlapping portion of the inner annular hanging portion 303 and the first annular protruding portion 204, and the sealing portion formed by the labyrinth action formed on the overlapping portion of the outer annular hanging portion 305 and the second annular protruding portion 206, respectively. Protected against ingress of dust and muddy water. Since the annular taper portion 309 is formed of synthetic resin having excellent friction characteristics in sliding contact with the upper spring seat, it does not deteriorate sliding characteristics and affects smooth steering operation. Never give.

FIG. 4 shows another embodiment of the synthetic resin thrust bearing of the present invention. The synthetic resin thrust bearing according to this embodiment is the thrust bearing according to the above-mentioned embodiment further having a sealed portion formed by a labyrinth action on the inner peripheral surface side. Other configurations in the figure are the same as those in the above-described embodiment, and are denoted by the same reference numerals. In this embodiment, the bearing sliding surface formed between the upper bearing case 300 and the lower bearing case 200 is elastically attached to the engaging hook portion 308 and the engaging portion 209 described in the above embodiment. In addition to the portion, the overlapping portion of the inner annular hanging portion 303 and the first annular protruding portion 204, the overlapping portion of the outer annular hanging portion 305 and the second annular protruding portion 206, the annular hanging portion 311 and the annular protruding portion 211. The labyrinth seals formed in each of the overlapping portions protect the dust and muddy water from entering. Similarly, the sliding surface of the bearing is sealed by a sealing portion formed in the close contact portion between the annular taper portion 309 and the upper spring seat, so that dust, muddy water, etc., particularly from the outer diameter surface of the bearing, are prevented. Since it is protected from intrusion, smooth steering operation is maintained for a long period of time without causing deterioration of sliding characteristics due to intrusion of dust, muddy water, or the like into the bearing sliding surface.

FIG. 5 shows still another embodiment of the synthetic resin thrust bearing of the present invention. In this embodiment, instead of the projection 212 for positioning to the mating mounting portion formed on the lower surface of the disk-shaped portion 202 of the synthetic resin lower bearing case 200 in the synthetic resin thrust bearing 100, the lower bearing case is replaced. A cylindrical protruding portion 212a is formed on the lower surface of the disc-shaped portion 202 of the sleeve 200 so as to communicate with the central insertion hole 201 of the disc-shaped portion, and other configurations are indicated by the same reference numerals as those in the above-described embodiment. In the synthetic resin thrust bearing 100 according to this embodiment, the cylindrical protrusion 212a is press-fitted and fixed in a hole 702 formed in the center of the flat surface 701 of the upper spring seat 700.

Also in the synthetic resin thrust bearing having the structure shown in FIG. 4, the lower bearing case 20 made of synthetic resin is used.
0 on the lower surface of the disk-shaped portion 202, the central insertion hole 20 of the disk-shaped portion
It is also possible to form a cylindrical protrusion 212a communicating with 1.

[0021]

EFFECTS OF THE INVENTION An annular taper formed of synthetic resin on the elastic mounting portion of the upper and lower bearing cases and a sealing portion formed by the labyrinth action formed on the inner and outer peripheral overlapping portions and the upper bearing case. The sealing part formed in the close contact part between the negative part and the upper spring seat prevents foreign matter such as dust and muddy water from entering the bearing sliding surface, especially from the bearing outer diameter surface. The smooth steering force is maintained for a long period of time without deteriorating the frictional wear characteristics due to the entry of foreign matter into the vehicle.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a preferred embodiment of a synthetic resin thrust bearing according to the present invention.

FIG. 2 is a plan view showing a synthetic resin lower bearing case and a synthetic resin bearing body in FIG.

FIG. 3 is a vertical cross-sectional view showing a state where the synthetic resin thrust bearing shown in FIG. 1 is incorporated in a strut assembly.

4 is a vertical sectional view showing another embodiment of the synthetic resin thrust bearing shown in FIG.

5 is a longitudinal sectional view showing still another embodiment of the synthetic resin thrust bearing shown in FIG.

FIG. 6 is a vertical sectional view showing a conventional synthetic resin thrust bearing.

FIG. 7 is a vertical sectional view showing another conventional synthetic resin thrust bearing.

[Explanation of symbols]

 100 synthetic resin thrust bearing 200 synthetic resin lower bearing case 202 disc-shaped portion 203 annular flat surface portion 204 first annular protrusion portion 205 annular recess groove 206 second annular protrusion portion 208 annular engagement protrusion portion 209 engagement portion 210 Annular groove 211 Annular protrusion 300 Synthetic resin upper bearing case 302 Disc-shaped portion 303 Inner annular hanging portion 304 Annular groove 305 Outer annular hanging portion 307 Annular engaging hanging portion 308 Engaging hook portion 309 Annular taper -Part 310 Annular groove 311 Annular hanging part 400 Synthetic resin bearing body

Claims (3)

[Claims] 1. A disk-shaped portion (202) having an insertion hole (201) in a central portion thereof, and an annular flat surface portion (203) connected to the insertion hole on the upper surface of the disk-shaped portion, concentric with the insertion hole. Of the first annular protrusion (204) and the first annular protrusion that are radially outwardly spaced apart from each other and are spaced apart from each other. Wide annular groove (20
5) forming a second annular protrusion (206), an annular engagement protrusion (208) protruding from the outer peripheral edge of the disc-shaped portion, and an engagement formed on the outer peripheral surface of the annular engagement protrusion. Lower bearing case (200) made of synthetic resin having a joint portion (209), a disc-shaped portion (302) having a through hole (301) of the same diameter as the through hole in the central portion, and the disc. An inner annular hanging portion (303) communicating with the insertion hole on the lower surface of the annular portion, and a radially outer portion of the inner annular hanging portion (303) that is distant from the inner annular hanging portion with a space therebetween, and a disc-shaped portion. An outer annular hanging portion (305) forming a wide annular concave groove (304) with the lower surface of the annular engaging hanging portion (307) hanging on the outer peripheral surface of the disc-shaped portion, and an annular engaging hanging portion of the annular engaging hanging portion. The engaging hook portion (308) formed on the inner peripheral surface and the upper end portion of the outer peripheral surface of the disk-shaped portion enclose the outer peripheral surface of the annular engaging hanging portion downward from the upper end portion. To so gradually diverging to vertically have been thin annular Te - Pa - section (309) and the synthetic resin-made upper bearing Ke equipped with - scan and (300), circular hole in a central portion (401)
A synthetic resin bearing body (400) made of a disc having
The bearing body (400) is disposed in the annular groove by sliding its lower surface into contact with the bottom surface of the annular groove (205) of the lower bearing case (200). (30
In 0), the bottom surface of the annular groove (304) is brought into sliding contact with the upper surface of the bearing body, and the end portions of the inner annular hanging portion (303) and the outer annular hanging portion (305) are respectively located at the first of the lower bearing case. The end portions of the one annular protrusion portion (204) and the second annular protrusion portion (206) are overlapped and engaged in the radial direction thereof, and the engagement hook portion (308) of the annular engagement hanging portion (307) is attached to the lower portion. Engagement portion (20) of the outer peripheral surface of the annular engagement protrusion of the bearing case
9) is elastically attached to the elastic attachment portion and the inner annular hanging portion (3
03) and the first annular protrusion (204) and the outer annular hanging portion (305) and the second annular protrusion (206) at the respective overlapping portions to form a sealing portion by a labyrinth action and an annular shape of the upper bearing case. A synthetic resin thrust bearing characterized in that a taper portion surrounds an outer peripheral surface of the lower bearing case and is combined with the lower bearing case. 2. The wide annular recessed groove of the lower bearing case includes an annular groove (2) formed by an outer peripheral surface of the first annular protrusion and a bottom surface of the recessed groove.
An annular projection (211) is formed to define and project 10), and the wide annular concave groove of the upper bearing case is formed by the outer peripheral surface of the inner annular hanging portion and the bottom surface of the concave groove. Groove (31
0) is defined to hang down, and an annular hanging portion (311) is formed, and the annular hanging portion is combined with its end portion overlapping with the end portion of the annular protruding portion in the radial direction thereof. The synthetic resin thrust bearing according to claim 1, wherein a sealing portion formed by a labyrinth action is formed in the overlapping portion. 3. The upper bearing case is brought into contact with the vehicle-body-side mounting member, the lower bearing case is brought into contact with the upper spring seat, and the upper bearing case has an annular shape. An end portion of the taper portion is closely slid on the upper surface of the upper spring seat and is disposed between the upper spring seat of the strut of the strut assembly and the vehicle body side mounting member. Item 1 or 2
The synthetic resin thrust bearing described in.