JPS6136827Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a strut thrust bearing incorporated in a strut type suspension (McPherson type) in an automobile.

In general, strut-type suspensions are mainly used for the front wheels of automobiles, and are suspensions that combine coil springs with a strut assembly that has a hydraulic shock absorber built into an outer cylinder that is integrated with the axle.

When the strut assembly rotates with the coil spring due to steering operation, there are two types of suspensions: one in which the piston rod of the assembly rotates, and another in which the piston rod does not rotate. Radial and/or thrust bearings are required between the mounting member and the upper spring seat of the coil spring to allow smooth rotation of the assembly.

Conventionally, rolling bearings using balls or needles have been used for bearings in this area, but with rolling bearings, there is a risk of fatigue failure in the balls or needles due to minute vibrations, vibration loads, etc. There is a problem that it is difficult to maintain steering operation.

In addition, these bearings are equipped with dust seals to prevent foreign matter such as dust from entering the sliding surfaces, but this is far from perfect and galling may occur due to foreign matter that has entered. There are also problems such as high steering force due to the high frictional force of the elastic body.

The present invention relates to a strut thrust bearing which is used in a strut type suspension in which the piston rod of the strut thrust assembly described above does not rotate due to steering operation, and which solves the above-mentioned problems. In a strut thrust bearing, which is arranged between a mounting member of a vehicle body that fixes a piston rod of an assembly and an upper spring seat of a coil spring loosely inserted into the piston rod, a strut thrust bearing is formed integrally with a cylindrical part and an end of the cylindrical part. The end face of the flange has an annular groove, an annular groove surrounding the annular groove, and a plurality of radial grooves communicating with the annular groove and opening into the central insertion hole. A thin elastic lip portion is formed on the outer circumferential edge of the flange connected to the annular groove, the end of which protrudes from the end surface of the flange, and the cylindrical portion is fitted onto the outer circumferential surface of the piston rod, and a synthetic resin strut that is fitted and held in the upper spring seat sheet, the thin elastic lip portion being compressed toward the mounting member and elastically deformed radially outward, and in close sliding contact with the mounting member. It provides a thrust bearing.

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 is a shock absorber constituting the strut assembly A, and 2 is its piston rod.
One end of the piston rod 2 is inserted into the shock absorber 1, and the other end is screwed and fixed by a nut 4 to a mounting member 3 which projects from the shock absorber 1 and is supported by the vehicle body via an elastic body.

5 is a lower spring seat fixed to the outer cylinder of the shock absorber 1.

Reference numeral 6 denotes an upper spring seat sheet disposed opposite to the lower spring seat sheet 5, and the upper spring seat sheet 6 has a flat portion 61 formed therein.

7 is a circular hole provided in the center of the flat portion 61, and 71 is a small hole provided in the flat portion 61 at a position apart from the circular hole 7.

The upper spring seat seat 6 is loosely inserted into the outer peripheral surface of the piston rod 2 in a circular hole 7.

8 is a coil spring disposed between the lower spring seat sheet 5 and the upper spring seat sheet 6.

Reference numeral 9 denotes a synthetic resin thrust bearing disposed between the upper spring seat 6 and the lower surface of the mounting member 3.

The thrust bearing 9 consists of a cylindrical portion 92 having a through hole 91 on its inner surface, and a flange portion 93 integrally formed at the end of the cylindrical portion 92. An end surface 94 of the flange portion 93 forms a sliding surface. Form.

Reference numeral 95 denotes an annular groove formed at the peripheral edge of the end surface 94 of the flange portion 93.

Reference numeral 96 indicates a plurality of radial grooves formed on the end surface 94 of the flange portion 93. One end of the radial groove 96 communicates with the annular groove 95, and the other end communicates with the central insertion hole 9.
It opens at 1.

The depth of the radial groove 96 is shallower than the depth of the annular groove 95 with which one end of the groove 96 communicates. The annular groove 95 serves to accommodate dust and the like that enter from the outside and prevent the dust from entering the sliding surface, and the radial groove 96 serves as a reservoir for lubricant such as grease.

Reference numeral 97 denotes an annular groove formed around an annular groove 95 formed at the peripheral edge of the flange end face 94.

Reference numeral 98 denotes a thin elastic lip portion formed on the outer periphery of the flange continuous with the annular groove 97, and the thin elastic lip portion 98 is formed to protrude from the end surface 94 of the flange portion.

FIG. 4 shows another embodiment of the thin elastic lip portion 98 formed on the outer periphery of the collar, in which an annular groove 95
The depth of the annular groove 97 formed surrounding the annular groove 97 is formed to be deeper than the depth of the annular groove 95.
The thin elastic lip portion 98 connected to the lip portion 7 has an elastic effect on the outer side in the radial direction.

5 and 6, a thin elastic lip portion 98 connected to the annular groove 97 is formed into a truncated cone shape whose diameter expands in the direction of the flange end surface 94, and the thin elastic lip portion 98 is provided with a radial direction. It has an elastic effect on the outside.

The thin elastic lip portion 98 described above can be elastically deformed outward in the radial direction, and when placed between the upper spring seat sheet 6 and the lower surface of the mounting member 3, the lip portion 98 deforms on the lower surface of the mounting member 3. By elastically deforming outward in the radial direction and coming into close sliding contact with the lower surface of the mounting member, it serves to prevent dust and the like from entering into the flange end surface 94, that is, the sliding surface.

Reference numeral 99 denotes a protrusion integrally formed on the back surface of the flange end face 94, and the protrusion 99 fits into the small hole 71 provided in the upper spring seat sheet 6 to serve as a rotation stopper for the bearing. . Note that this rotation stopper can also be achieved by forming a protrusion on the outer peripheral surface of the cylindrical portion 92 and fitting the protrusion into a notch formed in the circular hole 7 of the upper spring seat sheet 6.

The material constituting the above-mentioned thrust bearing 9 is a synthetic resin, especially a polyacetal resin, a polyamide resin, or one of these resins containing a lubricant, which has excellent friction and wear characteristics, self-lubricating properties, and impact resistance. Oil-containing synthetic resins are preferably used.

In the thrust bearing 9 having the above-described configuration, the piston rod 2 is fitted into the central insertion hole 91, and the outer peripheral surface of the cylindrical portion 92 is inserted into the upper spring seat 6.
The upper spring seat sheet 6 is fitted into the circular hole 7 provided in the flat part 61 of the upper spring seat sheet 6, and the protrusion 99 is fitted into the small hole 71.
It is arranged on the plane part 61 of.

The thrust bearing 9 is connected to the upper spring seat seat 6.
and the coil spring 8 arranged between the lower spring seat 5 and the lower spring seat 5.
Due to the elastic force, the thin elastic lip portion 98 is compressed toward the lower surface of the mounting member 3, and is elastically deformed radially outward until the flange end surface 94, that is, the sliding surface comes into sliding contact with the lower surface of the mounting member 3, and the mounting member 3 is attached. It is brought into close sliding contact with the member 3. This thin elastic lip portion 98 comes into close sliding contact with the lower surface of the mounting member 3, thereby preventing dust and the like from entering the sliding surface from the outside.

Furthermore, even if dust or the like enters beyond the thin elastic lip portion 98, it will be contained in the annular groove 97 connected to the lip portion 98 and the annular groove 95 formed inside the annular groove 97. This prevents dust, etc., from entering the sliding surface.

As described above, in the strut thrust bearing of the present invention, a thin elastic lip portion is integrally formed surrounding the sliding surface, and the thin elastic lip portion is formed to be elastically deformable outward in the radial direction. Therefore, when placed between the mounting member supported by the vehicle body via an elastic body and the upper spring seat sheet, its elastic deformation makes close sliding contact with the lower surface of the mounting member, preventing dust from entering the sliding surface. Furthermore, even if dust or the like enters beyond the elastic lip part, it will be contained in the annular groove connected to the elastic lip part and furthermore in the annular groove formed inside the annular groove. The intrusion prevention means completely prevents dust and the like from entering the sliding surface, allowing smooth steering operation over a long period of time.

In addition, since this type of bearing does not require a dust seal, which is indispensable, it not only simplifies installation during assembly, but also reduces the number of parts and, ultimately, costs. It is.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing how the strut thrust bearing is used, Fig. 2 is a plan view of the strut thrust bearing of the present invention, and Fig. 3 is a sectional view taken along the line X--X of Fig. 2. 4 is a sectional view showing another embodiment, FIG. 5 is a plan view showing another embodiment, and FIG. 6 is a sectional view taken along the line Y--Y in FIG. 5. 1: Shock absorber, 2: Piston rod,
3: Mounting member, 6: Upper spring seat sheet, 8: Coil spring, 9: Thrust bearing, 92: Cylindrical part, 9
3: Flange, 95: Annular groove, 96: Radial groove, 9
7: Annular groove, 98: Thin elastic lip portion.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a strut thrust bearing disposed between a mounting member of a vehicle body to which a piston rod of a strut assembly is fixed and an upper spring seat of a coil spring loosely inserted into the piston rod,
Consisting of a cylindrical part and a flange integrally formed at the end of the cylindrical part, the end face of the flange has an annular groove on its peripheral edge, an annular groove surrounding the annular groove, and a groove communicating with the annular groove. A plurality of radial grooves opening into the central insertion hole are formed, and a thin elastic lip portion is formed on the outer peripheral edge of the flange connected to the annular recess with its end protruding from the end surface of the flange. The cylindrical portion is fitted onto the outer circumferential surface of the piston rod, and is also fitted onto and held by the upper spring seat, and the thin elastic lip portion is compressed toward the mounting member and elastically deforms outward in the radial direction, so that it is connected to the mounting member. A synthetic resin strut thrust bearing with close sliding contact. (2) The synthetic resin strut thrust bearing according to claim 1, wherein the thin elastic lip portion on the outer periphery of the collar is formed in the shape of a truncated cone whose diameter increases in the direction of the end face of the collar.