JPH0139934Y2 - - Google Patents

Description

[Detailed description of the invention] [Purpose of the invention] "Field of industrial application" This invention relates to thrust ball bearings, particularly thrust ball bearings used in suspension systems of automobiles.

``Prior art'' When thrust ball bearings are used in automobile McPherson strut-type suspension systems, most of the members that come into contact with the thrust ball bearings are made of sheet metal, which results in poor dimensional accuracy such as flatness. This caused problems such as the contact surface with the contact surface being in partial contact (contact), causing fretting corrosion due to minute slippage, and generating noise. In addition, the environment inside the tire house where such thrust ball bearings are used is extremely poor, with muddy water splashing around, and the steel seal plates rusting, causing problems such as rust or dust entering the rolling surfaces and causing damage. It was hot.

Therefore, a unit has been proposed in which such a metal thrust ball bearing is housed in a synthetic resin case. An example of this is shown in the longitudinal sectional view of FIG. A thrust ball bearing 7 is a rolling element 4 held between bearing rings 1 and 2.
A lower case 13 made of synthetic resin containing the bearing ring 2 is sealed and covered by an upper case 12 made of synthetic resin containing the bearing ring 1.

Figure 12 is a vertical sectional view of a separate input suspension type suspension, showing an example of a McPherson strut type suspension system for an automobile, which uses a thrust ball bearing unit in which a thrust ball bearing is housed in a synthetic resin case. Only shown. 1st
In Figure 2, the upper mount 3 is fixed to the body 33 with a mounting bolt nut 47.
A shock absorber rod 37 is attached to a nut 38 screwed into the rod end plate 32 which is fixed to the rod end plate 32 via a rubber mount 35 on the rod 4.
Fixed by The upper mount 34 also serves as a bearing holder, and the upper case 12 is fitted into a cylindrical portion 45 of the upper mount 34. The cylindrical portion 41 of the spring seat 39 is fitted into the inner diameter of the lower case 13 of the thrust ball bearing unit.
One end of a coil spring 42 of the suspension device is fitted into 9 via an elastic sheet 40 made of rubber or the like. The other end of the coil spring 42 is the shock absorber body 43
It is supported by a spring seat 44 provided at.

Thrust ball bearings require strict dimensional accuracy, especially flatness and flatness, of the mating member that houses them, but in the above suspension system, the upper mount 34 is usually press-formed from sheet metal, so the above accuracy can be satisfied. There are few parts, and there is damage due to uniform stress concentration that causes partial impressions on the bearing rings 1 and 2 due to uneven contact. For this reason, some require a separate member with sufficient flatness and flatness to attach the upper mount 34.
Alternatively, there is also a structure arranged on a spring seat 39. In addition, in the case of the above-described structure, since there is a bolt head of the bolt nut 47 that fastens the upper mount 38 and the body 33, the upper case 12 has an uneven wall thickness, which has the disadvantage that it is likely to warp due to manufacturing.

Therefore, as shown in FIG. 10, an annular groove 49 was provided in the upper case 12, and a number of radial protrusions 51 were provided around the center of the bearing, which were expanded along the circumference along the cross-sectional line A-A in FIG. As shown in FIG. 11, which is a sectional view, there is one in which the bearing ring 1 is brought into contact with the protrusion 51. In this case, the protrusion 51 is eliminated from the portion where the bolt head for fastening the body 33 and the upper mount 34 is located, so that the wall thickness can be made uniform.

``Problem to be solved by the invention'' In the thrust ball bearing unit shown in FIG. 10, the surface of the upper case 12 in contact with the upper mount is a flat surface,
The uneven load due to the unevenness of the seat surface is caused by upper case 1.
2 is made of synthetic resin, it is recognized that it is applied to the thrust ball bearing 7 regardless. This is inside the upper case 12, the outer cylindrical hanging part 16, 2
The protrusions 51 are continuous on the upper case 1, and if there are few protrusions 51, the bearing ring 1 receives a concentrated load due to the protrusions 51 themselves even if the bearing ring 1 is uniform. This is thought to be due to the fact that 12 adapts to the unevenness of the upper mount and is less likely to deform.

Furthermore, if a thrust ball bearing unit such as this, which is housed in a synthetic resin case, is used in an input-separated suspension in which the bearing is placed directly on the body, rolling vibrations will occur due to the deformation of the bearing ring. Small rolling vibrations may be transmitted directly to the body. or,
Since the case of the thrust ball bearing unit shown in FIG. 10 is rigid, it has the disadvantage that impact loads are easily transmitted to the thrust ball bearing.

The present invention solves the above-mentioned problems with thrust ball bearing units housed in synthetic resin cases, so that the bearing ring does not deform, and even if bearing vibration noise is generated, the rolling vibration noise will not be transmitted to the mating mounting member. It is an object of the present invention to provide a thrust ball bearing unit that is difficult to transmit and has good shock absorption properties.

[Structure of the idea]

``Means for solving the problem'' This idea consists of a synthetic resin upper and lower case, a metal upper and lower bearing ring held in the upper and lower case, and a metal bearing ring placed between the raceway surfaces of the bearing ring. The upper case is a thrust ball bearing unit consisting of a rolling element, and the upper case includes a ring plate-shaped base, an inner and outer cylindrical hanging part formed on the outer periphery of the ring plate-shaped base, and an inner and outer cylindrical hanging part. The lower case has a lip portion formed at the lower end, and the lower case includes a ring plate-shaped base, an inner and outer cylindrical protrusion formed on the inner and outer periphery of the ring plate-shaped base, and a cylindrical protrusion on the inner and outer circumference of the ring plate-like base. The upper case has a lip portion formed at the upper end, and the upper case elastically attaches the lower lip portion of the inner and outer circumferential cylindrical hanging portion to the upper lip portion of the inner and outer circumferential cylindrical projection of the lower case. is combined with the lower case so as to cover the outer circumferential surface of the lower case, and a sealing part by a labyrinth effect is formed in the elastic mounting part, and a rolling element is held between the raceway surfaces in the upper and lower cases, and A lower bearing ring is arranged between the upper case and/or the lower case via a cushioning material, and a large number of protrusions are provided on the upper surface of the ring plate-shaped base of the upper case and/or the lower surface of the ring plate-shaped base of the lower case. This is a thrust ball bearing unit characterized in that a part is formed.

"Operation" A large number of protrusions formed on the upper surface of the ring plate-shaped base of the synthetic resin upper case and/or the lower surface of the ring plate-shaped base of the synthetic resin lower case deform to adapt to the mating member, and the upper and lower parts This prevents deformation of the ring-shaped base of the case and prevents deformation of the bearing ring due to load. The impact load is alleviated by the numerous protrusions formed on the upper surface of the annular base of the synthetic resin upper case and/or the lower surface of the annular plate base of the synthetic resin lower case, and is completely absorbed by the cushioning material. No impact load is applied to the thrust ball bearing.

Even if rolling vibration occurs in the thrust ball bearing, the vibration is absorbed by the buffer material.

"Embodiments" Hereinafter, the present invention will be described in detail with reference to the accompanying drawings showing embodiments thereof.

FIG. 1 is a longitudinal sectional view of the thrust ball bearing unit, and FIG. 2 is a plan view of FIG. 1.

The metal upper bearing ring 1 has its outer diameter D ₁ and inner diameter
d ₁ is slightly larger than the outer diameter D 2 and inner diameter d ₂ of the metal lower bearing ring ₂ facing the upper bearing ring 1, and the outer diameter D ₁ of the upper bearing ring 1 is The raceway surface 8 of the raceway 1 and the inner diameter d ₂ of the lower raceway 2 are formed to be exactly concentric with the raceway surface 9 of the raceway 2. The end surface 5 of the upper bearing ring 1 and the end surface 11 of the lower bearing ring 2, in other words, the surfaces opposite to the surfaces on which the raceway surfaces 8 and 9 are formed, each form a plane perpendicular to the axis, and the end surface 5 , 11 and the inner and outer diameter surfaces continuous to the end surfaces 5 and 11 are chamfered. Raceway surfaces 8 and 9 formed on the upper and lower raceway rings 1 and 2
each has an arcuate cross section with a radius slightly larger than the radius of the sphere forming the rolling element 4. The rolling elements 4 are rotatably held between the raceway surfaces 8 and 9 of the upper and lower bearing rings 1 and 2. The upper case 12 is made of synthetic resin, such as polyacetal resin, polyamide resin, etc.
2 includes an annular plate-shaped base 19 having a large number of radial protrusions 26 on the upper surface, an inner part formed on the outer peripheral edge of the annular plate-shaped base 19, an outer cylindrical hanging part 16, 21, and an inner part of the annular plate-shaped base 19;
The inwardly narrowing lip portions 17, 22 formed at the lower ends of the outer circumferential cylindrical hanging portions 16, 21 and the lower surfaces of the annular plate-shaped base 19, that is, the inner and outer circumferential cylindrical hanging portions 16,
It has a downward circumferential groove 6 formed on the lower surface of the ring-shaped base 19 surrounded by 21.

The large number of radial protrusions 26 formed on the upper surface of the annular plate-shaped base 19 have different sizes and shapes, so that if a load is applied unevenly to that part, only the protrusions 26 will be distorted unevenly and the load will be equalized. and the annular base 19
It is designed to ensure that a uniform load is transmitted.

The upper bearing ring 1 has an end face 5 connected to the upper case 12.
It is held in the upper case 12 by being fitted into a circumferential groove 6 formed on the lower surface of the annular plate-shaped base 19 via an annular buffer material 25 disposed within the circumferential groove 6.

The annular buffer material 25 arranged in the circumferential groove 6 is
The material used is selected from elastic materials such as rubber, soft synthetic resins, gasket materials (including gasket materials impregnated with viscous material), steel mesh, etc.

The lower case 13 is similar to the upper case 12,
The lower case 13 is made of synthetic resin.
, an annular plate-shaped base 36 and an inner cylindrical protrusion 14 formed with a step 18 on the inner peripheral edge of the annular plate-shaped base 36;
An outer cylindrical protrusion 23 is formed on the outer periphery of the annular plate-shaped base 36, and lip parts 15 and 20 are formed on the upper ends of the inner and outer cylindrical protrusions, respectively.

The lower bearing ring 2 has an end face 11 connected to the lower case 1.
3, the lower case 1 is brought into contact with the upper surface of the annular plate-shaped base 36 surrounded by the outer circumferential cylindrical protrusions 14 and 23.
It is fitted into the cylindrical portion 10 of No. 3.

In the above-described configuration, the inner diameter d ₄ of the inner cylindrical projecting portion 14 of the lower case 13 is slightly smaller than the inner diameter d ₃ of the inner cylindrical hanging portion 16 of the upper case 12 .

The upper and lower cases 12 and 13 holding the upper and lower bearing rings 1 and 2 respectively hold the rolling elements 4 between the raceway surfaces 8 and 9 of the upper and lower bearing rings 1 and 2,
Inside the upper case 12, the outer peripheral cylindrical hanging portions 16, 2
1 to the lower end lip portions 17 and 22 of the lower case 13.
Among these, elastic devices (snap fittings) are attached to the upper end lip portions 15 and 20 of the outer circumferential cylindrical protruding portions 14 and 23, respectively, for assembly.

In the thrust ball bearing unit assembled in this manner, a sealing portion by a labyrinth effect is formed in each of the elastic mounting portions on the outer circumferential surface of the thrust ball bearing unit, thereby preventing dust and the like from entering the sliding surface of the bearing unit.

Note that reference numeral 46 in the figure is a recess formed on the upper surface of the annular plate-shaped base 19 of the upper case 12 so as to face each other in the radial direction. This is to prevent the bolt head of the bolt nut 47 shown from hitting the bolt. Depending on the structure of the strut, the bolt head may not protrude from the bearing surface of the thrust ball bearing, and in such cases there is no need to provide this recess 46.

FIG. 3 is a longitudinal sectional view showing another embodiment of this invention. This embodiment differs from the previous embodiment in that the cushioning material 25
The only difference is the shape of the mounting groove, and the other features are the same.

A cylindrical surface portion 24 larger than the diameter of the outer periphery of the circumferential groove 6 is formed on the outer cylindrical hanging portion 21 side of the circumferential groove 6 formed on the lower surface of the ring-shaped base 19 of the upper case 12, A cushioning material 25 is inserted into the circumferential groove 6, a part of the cushioning material 25 is made to protrude from the circumferential groove 6, and the upper bearing ring 1 is disposed on the protruding cushioning material 25, and the bearing ring is The outer circumferential surface of the cylindrical surface portion 24 is fitted into the cylindrical surface portion 24.
In this configuration, the circumferential groove 6 of the buffer material 25
A space is formed at the periphery of the more protruding portion.

FIG. 4 is a longitudinal sectional view showing still another embodiment of this invention, which includes a cushioning material 25 and a cushioning material 25.
The circumferential groove 6 for holding the ring 5 is different from the embodiment shown in FIG. 1, but the rest is the same as the embodiment shown in FIG.

The buffer material 25 is disposed in contact with the lower surface of the annular plate-shaped base 19 of the upper case 12 surrounded by the outer peripheral cylindrical hanging parts 16 and 21. The width of the cushioning material 25 is equal to or larger than the width of the upper bearing ring 1, and the cushioning material 25 is made of a material with excellent creep resistance.

FIG. 5 is a longitudinal cross-sectional view showing an embodiment in which the shape of a large number of protrusions formed on the upper surface of the annular base 19 of the upper case 12 is changed, and FIG. 6 is a plan view of FIG. 5.

On the upper surface of the annular plate-shaped base 19 of the upper case 12, there are many points on the inner and outer circumferential sides thereof, and between the inner and outer annular protrusions 27 and 28, respectively. A protrusion 29 that protrudes in the shape of
is formed.

The thrust ball bearing unit consisting of the embodiment shown in FIGS. 1 to 6 described above is
A case where the device is installed in the suspension system of an automobile shown in the figure will be explained.

Assuming that the upper mount 34 constituting the suspension system has irregularities, there are many protrusions (radial protrusions 26 in the embodiment shown in FIGS. 1 to 4) formed on the upper surface of the annular base 19 of the upper case 12. , in the embodiment shown in FIGS. 5 and 6, the inner and outer annular protrusions 2
7, 28 and a large number of dot-shaped protrusions 29) are strongly pressed and easily deformed at the convex portions of the upper mount 34, so that the annular plate-shaped base 19 can be imitated without being deformed. Therefore, even if a load is applied, the bearing ring 1 will not be deformed. Even if the annular plate-shaped base 19 is deformed, the cushioning material 25 absorbs the deformation, so that the raceway ring 1 will not be deformed. Therefore, rolling vibration noise is not generated, and even if rolling vibration noise is generated, the vibration is absorbed by the buffer material 25 and is prevented from being transmitted to the body 33.

Ring-shaped base 1 for sudden loads during bumps
The upper surface protrusion of 9 cushions the impact, and the buffer material 25 absorbs the impact.
Also, an excessive load is not applied to the rolling elements 4 held between the raceway surfaces 8 and 9 of the bearing ring.

In the embodiment described above, the cushioning material 25 is arranged between the upper case 12 and the upper bearing ring 1, and a large number of protrusions 26 are formed on the upper surface of the ring-shaped base 19 of the upper case 12. However, the cushioning material 25 may be arranged between the lower case 13 and the lower raceway ring 2, or at both positions. Further, a large number of protrusions 26 formed on the upper surface of the annular plate-shaped base 19 of the upper case 12 are connected to the annular plate-shaped base 3 of the lower case 13.
6, or on both the upper and lower surfaces of the annular plate-shaped bases 19, 36 of the upper and lower cases 12, 13. That is, the upper and lower cases 12, 13
cushioning material 25 and upper and lower cases 12,
The large number of protrusions formed on the 13 annular plate bases can be freely combined.

The shapes of the radial protrusions 26 formed on the annular bases of the upper and lower cases 12 and 13 are shown in FIG.
It may be arranged as shown in FIG.

In FIG. 7, protrusions 31, 31 are formed in the circumferential direction on the inner and outer peripheral edges of the upper surface of the annular plate-shaped base 19, and the tips of the radial protrusions 26 are projected outside of the protrusions 31, 31. be.

In this way, the upper and lower cases 12, 13
The rigidity of the protrusion 26 is increased, and the tip of the protrusion 26 conforms to the mating seating surface. In FIG. 8, the shape of the radial protrusion 26 is set as a trapezoid, and the width W of the upper side is set as above.
The width is approximately that of the lower bearing rings 1 and 2. In this way, the protruding portion 26 is easily bent, easily adapts to the mating seating surface, and has a great ability to reduce impact.

[Effect of the invention] Since the cushioning material is arranged between the upper case and the upper bearing ring or between the lower case and the lower bearing ring, even if the ring plate-shaped base of the case is deformed, The deformation is absorbed by the cushioning material, and the deformation does not extend to the raceway.

When an impact load is applied, the synthetic resin case cushions it, and the cushioning material absorbs the impact, preventing excessive load from being applied to the bearing ring.

Even if rolling vibration noise occurs, the cushioning material absorbs this vibration and does not transmit it to the mating mounting member.

A large number of protrusions are formed on the upper surface of the ring plate-shaped base of the upper case and/or the lower surface of the ring plate-shaped base of the lower case, so that even if the mating mounting member has unevenness, it will fit in and prevent the ring plate-shaped base from deforming. Therefore, the deformation does not affect the bearing ring.

The upper and lower cases are assembled together by being elastically mounted on the outer circumference side, and a labyrinth sealed portion is formed in the elastic mounting portion to prevent dust and the like from entering the sliding surface.

Since the upper and lower cases are assembled together by being elastically attached on their outer peripheral surfaces, the assembly work is improved and the workability of assembling them into the suspension system is also improved.

[Brief explanation of the drawing]

1 to 8 respectively show embodiments of the present invention, FIGS. 1 and 3 to 5 are longitudinal sectional views, FIG. 2 is a plan view of FIG. 1, and FIG. 7 and 8 are longitudinal sectional views showing the shape of the protrusion, and FIGS. 9 and 10 are longitudinal sectional views of the conventional example,
Figure 11 is a cross-sectional development view taken along line A-A in Figure 10;
The figure is a longitudinal sectional view of an automobile suspension system equipped with thrust ball bearings. 1... Upper bearing ring, 2... Lower bearing ring, 4... Rolling element, 8, 9... Raceway surface, 12... Upper case,
13... lower case, 14... inner cylindrical protrusion,
15...Rip part, 16...Inner cylindrical hanging part, 1
7... Lip portion, 19... Annular plate base, 21...
Outer circumference cylindrical hanging part, 22... lip part, 23... outer periphery cylindrical protrusion part, 25... cushioning material, 26... protrusion part, 36... ring plate-shaped base.

Claims (1)

[Scope of utility model registration request] synthetic resin upper and lower cases 12 and 13;
A metal top held in the lower case 12, 13,
This is a thrust ball bearing unit consisting of lower bearing rings 1 and 2 and rolling elements 4 arranged between raceway surfaces 9 and 8 of the bearing rings. The lower case 13 includes inner and outer cylindrical hanging parts 16 and 21 formed on the outer periphery of the base and lip parts 17 and 22 formed at the lower ends of the inner and outer cylindrical hanging parts 16 and 21, respectively. The annular plate-shaped base 36 and the inner part of the annular plate-shaped base, the inner part formed on the outer peripheral edge, the outer cylindrical protrusion part 14, 23 and the inner part,
Lip portion 1 formed at the upper end of the outer cylindrical protrusion
5, 20, and the upper case 12 has lower lip portions 1 of the inner and outer cylindrical hanging portions 16, 21.
7 and 22 are elastically attached to the upper lip portions 15 and 20 of the outer cylindrical projections 14 and 23 of the lower case 13, and are combined with the lower case 13 so as to cover the outer peripheral surfaces of the upper lip portions 15 and 20. At the same time, a sealing part is formed in the elastic mounting part by a labyrinth effect, and in the upper and lower cases 12 and 13, the rolling elements 4 are held between the raceway surfaces 8 and 9, and the lower raceway rings 1 and 2 are held. are arranged between the upper case 12 and/or the lower case 13 via a cushioning material 25, and are arranged on the upper surface of the annular plate-shaped base 19 of the upper case 12 and/or the lower surface of the annular plate-shaped base 36 of the lower case 13. is a large number of protrusions 26, 27,
A thrust ball bearing unit characterized in that 28 and 29 are formed.