JPH0121213Y2 - - 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" FIG. 4 is a longitudinal sectional view of a conventional thrust ball bearing with a sealing function. Raceway ring 1,
A rolling element 4 of a ball is in contact with the ball 2 with a distance maintained by a separator 30, and the end face 5 of the bearing ring 1 and the cylindrical outer periphery of a seal plate 6 held on the outer periphery cover the outside of the bearing rings 1 and 2 and provide a seal. plate 6
The cylindrical outer circumferential end of the bearing ring 2 is deformed inwardly so that in the installed state, the bearing ring 2 hugs the vicinity of the outer circumference of the seat surface of the bearing ring 2 at a distance.

An example in which such a thrust ball bearing 7 is used in a McPherson strut type suspension system for an automobile is shown in FIG. In FIG. 5, a bearing holder 43 is integrally molded and held on an upper mount 41 fixed to a body 39 via a rubber mount 42 vulcanized and bonded.
The end of a shock absorber rod 44 is fitted into the bearing holder 43 and fixed to the rod 44 side of the shock absorber by a nut 45 screwed into the rod 44. Bearing holder 43
A spring seat 46 is attached to the inner diameter of the bearing ring 2 of the thrust ball bearing 7 shown in FIG.
A cylindrical portion 52 is fitted into the spring seat 46, and one end of a coil spring 47 of the suspension device is fitted into the spring seat 46. The other end of the coil spring 47 is supported by a spring seat 49 provided on the shock absorber body 48. The shock absorber main body 48 is provided with a mounting flange 51 that is attached to a knuckle supported by the body 39 via a link.

``Problem that the invention is trying to solve'' According to an example in which the thrust ball bearing 7 shown in Fig. 4 is used in the suspension system of a car as shown in Fig. 5, the thrust ball bearing 7 shown in Fig. 5 is placed above the tire house. This is because dust, etc. enters around the rolling elements 4 from between the seal plate 6 and the bearing ring 2 on the shaft side and between the spring seat 46 and the shock absorber rod 44, causing the rolling elements to rotate at an early stage. Disabling problems may occur.

The purpose of this invention is to provide a thrust ball bearing with excellent sealing performance.

[Structure of the idea]

``Means for solving the problem'' This idea is based on an upper and lower annular synthetic resin case with a roughly U-shaped cross section, in which raceway rings are fitted and housed with their raceway surfaces facing each other. Between the raceway rings, there is a separator part and a sharp lip part on the inner periphery of the separator part, the tip of which faces diagonally toward the axis, and the outer periphery of the separator part, the tip of which faces diagonally to the outside in the radial direction. A seal separator provided with the seal separator is disposed with the sharp lip portion slidingly in contact with the raceway ring, and spherical rolling elements are disposed on the separator portion in contact with the raceway surface to maintain a spacing. This is a thrust ball bearing characterized in that the upper and lower cases made of synthetic resin are fitted with seals that act as a ravine on the inner and outer peripheries, respectively.

"Function" Because the sharp lip of the seal separator is in sliding contact with both bearing rings, the rolling elements move in a sealed space, and the seal has a labyrinth effect on the inner and outer periphery of the synthetic resin upper and lower cases, respectively. Since the contact area between the raceway ring and the rolling element is double sealed, dust and the like are prevented from entering the area.

"Example" Hereinafter, an example of this invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view. Metal bearing ring 1,
2 are fitted into upper and lower cases 29 and 31 made of synthetic resin, such as polyacetal resin or polyamide resin, each having a roughly U-shaped cross section, with their raceway surfaces facing each other. Outer diameter of the upper case 29 that is normally attached to the casing side
D ₁ is slightly larger than the outer diameter 2 of the lower case 31 that is normally fitted on the shaft side, and is the outer diameter D ₁ of the upper case 29.
is the bearing ring 1 fitted and housed in the upper case 29.
It is made to be exactly concentric with the orbital surface 8 of. The inner diameter d ₂ of the lower case 31 is slightly smaller than the inner diameter d ₁ of the upper case 29 and is made to be exactly concentric with the raceway surface 9 of the raceway ring 2 fitted and housed in the lower case 31 .

The end surface 5 of the upper case 29 and the mounting surface 11 of the lower case 31 form a plane perpendicular to the axis.
5 and the inner and outer diameters that follow the surfaces 11 and 5 are chamfered.

The raceway surfaces 8 and 9 have an inner arcuate cross section with a radius slightly larger than the radius of the ball of the rolling element 4, and both sides of the raceway surfaces 8 and 9 are opposite planes 12 and 1 perpendicular to the axis.
3, 14, and 15 have a smooth finish. The rolling elements 4 are held by a seal separator 3.

The upper cases 29 and 31 have an annular shape centered on the shaft, and the ends of the upper case 29 and the lower case 31 face each other on the inner diameter side, and a circumferential groove 3 is formed in the end of the upper case 29.
2 is provided on the lower case 31, and an annular protrusion 33 that fits into the circumferential groove 32 with a short distance is provided on the lower case 31. And the lower case 31 where the protrusion 33 is provided
The end face 34 of the upper case 29 faces the end face 35 of the upper case 29 with a small distance. The outer circumferential end of the upper case 29 is snap-fitted to the outer circumferential side of the lower case 31, and is connected to the opposing cylindrical spaces 36, 3.
7 is a conical gap 38, which communicates the inside and outside of the bearing with a minute gap.

In FIG. 1, when the upper and lower cases 29 and 31 rotate relative to each other, the bearing inner diameter side
31 between the end surfaces 35 and 34 and the protrusion 33,
In the space between the circumferential grooves 32, the outer diameter side of the bearing is sealed by a labyrinth action between the cylindrical space 36, the conical space 38, and the space between the cylindrical gaps 37, respectively. Furthermore, when an impactful thrust load is applied, the bearing is protected by the buffering action of the upper and lower cases 29 and 31.

FIG. 2 is a longitudinal sectional view of the seal separator 3. The seal separator 3 is located between the opposing planes 12, 13 and 14, 15 of the bearing rings 1, 2 (first
The total thickness _t1 is slightly larger than that in Figure). The thickness t ₂ of the separator portion 21 which is integrated with the sharp lip portions 16, 17, 18, and 19 is formed into a flat annular shape with an axial center that is slightly smaller than the above-mentioned distance to.

The sharp lip portion 16 has a base side on the outer periphery of the separator portion 21, and a tip thereof faces the opposing plane 12 on the outer diameter side of the bearing ring 1 and is provided obliquely toward the outside in the radial direction of the thrust ball bearing. The base is thick and the tip has a sharp, almost triangular cross-sectional shape that rubs against the opposing plane 12 of the bearing ring 1.

The sharp lip part 17 has a base side on the outer periphery of the separator part 21, a tip facing the facing plane 13 on the outer diameter side of the bearing ring 2, and is provided obliquely toward the outside in the radial direction of the thrust ball bearing. The tip is thick and has a sharp, almost triangular cross-sectional shape that rubs against the opposing plane 13 of the raceway ring 2.

The sharp lip portion 18 has a base side on the inner periphery of the separator portion 21, and a tip thereof faces the opposing plane 14 on the inner diameter side of the bearing ring 1, and is obliquely provided toward the axis of the thrust ball bearing. The base is thick and the tip has a sharp, almost triangular cross-sectional shape that rubs against the opposing plane 14 of the bearing ring 1.

The sharp lip portion 19 has a base side on the inner periphery of the separator portion 21, and a tip thereof faces the opposing plane 15 on the inner diameter side of the bearing ring 2, and is obliquely provided toward the axis of the thrust ball bearing. The base is thick and the tip has a sharp, almost triangular cross-sectional shape that rubs against the opposing plane 15 of the bearing ring 2.

Adjacent surfaces of the sharp lip portions 16 and 17 and 18 and 19 have a V-shaped cross section. In such a cross section, the sharp lip portions 16, 17, 18, and 19 form an annular shape centered on the axis.

The tips of the sharp lip portions 16, 17, 18, 19 are connected to the opposing planes 12, 13, 14, 15 of the bearing rings 1, 2.
, and the opposing planes 12, 13, 1
4 and 15 and the inner and outer circumferences of bearing rings 1 and 2.

The separator part 21 has rolling elements 4 arranged at equal circumferences.
A holding hole 22 into which the holder is inserted is provided. Holding hole 22
The rolling elements 4 are allowed to rotate freely, and the rolling elements 4
The wall surface of the seal separator 3 has a spherical shape to prevent it from escaping from the seal separator 3.

The seal separator 3 prevents friction between the rolling elements 4, distributes the rolling elements 4 evenly to receive the load evenly, and protects against dust. It is made of a flexible synthetic resin material (for example, polyacetal resin, Polyamide resin, etc.).

In FIG. 1, when the upper and lower cases 29 and 31 rotate relative to each other, the bearing rings 1 and 2 also rotate relative to each other.
The rolling elements 4 rotate and revolve while carrying a load between the raceway surfaces 8 and 9 and the rolling elements 4. The seal separator 3 rotates at this revolution speed, and its sharp lip portion 1
6 and 17 compress and rub the opposing flat surfaces 12 and 14 of the bearing ring 1, and the sharp lip portions 17 and 19 compress and rub the opposing flat surfaces 13 and 15 of the bearing ring 2.
In addition to the labyrinth effect on the inner and outer diameter sides of the upper and lower cases 29 and 31 mentioned above, extremely fine dust also acts on the contact seal between the sharp lips 16, 17 and 18, 19 of the seal separator 3 and the bearing rings 1 and 2. It is dust-proof due to its action.

FIG. 3 is a longitudinal sectional view showing another embodiment of the seal separator 3. The outer shape is the same as that of the seal separator 3 shown in FIG. 2, and its explanation will be omitted. In this embodiment, a separator portion 21 is required to have relatively high rigidity and low friction against rolling elements, an outer lip ring 25 including sharp lip portions 16 and 17 on the outer circumferential side, and a sharp lip portion 18 on the inner circumferential side. 19, an annular groove is formed on the inner and outer peripheries of the separator portion 21, and an annular protrusion on the inner circumference of the outer lip ring 25 and an annular protrusion on the outer circumference of the inner lip ring 26 are provided. Inner and outer lip rings 25, 26 and the separator part 21 are integrally molded or assembled, and are provided with fitting parts 27 and 28 that engage with grooves on the inner and outer peripheries of the separator part 21. This separator portion 21 is made of the same material as the seal separator 3 of the embodiment shown in FIG.
26 is rubber or polyester elastomer,
Polyurethane or the like is used.

[Effect of idea]

This device has sharp lip portions on the inner and outer peripheries of the seal separator that holds the spherical rolling elements, and the sharp lip portions are placed in sliding contact with the raceway ring, so that the contact sealing action allows the raceway ring and the spherical rolling element to be separated. The contact portion is isolated from the outside, and it is possible to seal the contact portion with grease. Since both raceway rings are fitted and housed in synthetic resin upper and lower cases that have seals that act as a labyrinth on the inner and outer peripheries, respectively, the contact area between the raceway ring and the rolling elements has the aforementioned contact sealing effect and labyrinth. It is double sealed by the operative sealing means, and dust and the like are completely prevented from entering the contact area. Since the sharp lip part is assembled under bending action, the spring constant can be made small, and even if it wears out, there will be very little change in the sliding contact pressure with the bearing ring, and the sealing performance will be durable.

In the embodiment shown in Fig. 3, the separate part and the inner and outer lip rings can be made of different materials, so the material that is most suitable for holding the rolling elements can be selected for the separate part, and the material that is most suitable for the inner and outer rip rings as a contact seal. can be selected.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view of an embodiment of this invention;
3 are longitudinal sectional views of an embodiment of the seal separator portion, FIG. 4 is a longitudinal sectional view of a conventional example, and FIG. 5 is a longitudinal sectional view of an automobile suspension system. 1, 2... Raceway ring, 3... Seal separator,
4...Rolling element, 5...End face, 6...Seal plate, 7...Thrust ball bearing, 8, 9...
... Raceway surface, 11 ... Mounting surface, 12, 13, 14,
15... Opposing plane, 16, 17, 18, 19...
Sharp lip part, 21... Separator part, 22...
Holding hole, 25... Outer lip ring, 26... Inner lip ring, 27, 28... Fitting part, 29... Upper case,
30...Separator, 31...Lower case, 32...
... Circumferential groove, 33 ... Projection, 34, 35 ... End surface,
36, 37...Cylindrical shape, 38...Conical shape
39...Body, 41...Upper mount, 42...Rubber mount, 43...Bearing holder, 44...Shock absorber rod,
45...Natsuto, 46...Spring seat, 4
7...Coil spring, 48...Shock absorber body, 49...Spring seat, 51...Mounting flange,
52...Cylindrical part.

Claims (1)

[Scope of utility model registration request] Raceway rings are fitted and housed in the annular synthetic resin upper and lower cases, each having a roughly U-shaped cross section, with their raceway surfaces facing each other. A seal separator is provided with a sharp lip part on the inner periphery of which the tip faces diagonally toward the axis, and a sharp lip part on the outer periphery with the tip facing diagonally radially outward. The separator portion is arranged in sliding contact with the raceway surface, and spherical rolling elements are arranged in contact with the raceway surface to maintain a distance therebetween.
A thrust ball bearing characterized by the fact that the lower case is fitted with seals that act as labyrinths on the inner and outer sides, respectively.