JPH0777220A - Closed type thrust ball bearing - Google Patents

Abstract

PURPOSE:To reduce the cost of production in dispensing with a sealing member at the side of a bearing fitting objective unit by installing an auxiliary seal lip, forming a contact sealing part in a gap with the constituent parts of this beating fitting objective unit, in the leasing member being provided in a closed type thrust ball bearing. CONSTITUTION:This closed type thrust ball bearing A consists of both first and second ring races 1 and 2, plural balls 3, and both first and second sealing members 4 and 5. The first sealing mar 4 is made up of attaching an elastic body 4b such as rubber or the like to the outer circumferential surface of a core bar 4a to be externally fitted in an inner cylindrical part 1b of the ring race 1. In this case, both outer and inner main seal lips 4a and 4d and an auxilairy seal lip 4e projecting over the more outside than an outer surface of the second ring races 2 and coming into contact with a bearing fitting objective unit both are installed in this elastic body 4b. In addition, the second sealing member 5 is also made up of installing an auxiliary seal lip 5e in an elastic body 5b with both outer and inner seal lips 5c and 5d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealed thrust ball bearing used in, for example, a strut suspension system for a vehicle, and more particularly to a sealed thrust ball bearing of a type using a bearing ring formed by press molding from a thin steel plate. Regarding the improvement of.

[0002]

2. Description of the Related Art In a strut suspension device for a vehicle, a sealed thrust ball bearing is mounted between an upper mount member and a lower mount member.

In this type of sealed thrust ball bearing, two orbital rings are usually arranged so as to be opposed to each other in the axial direction, and the orbital rings are provided with opposing walls in the radial direction. A space surrounding the balls is formed, and a seal member is provided in a gap between the opposing wall and the bearing ring, and a lubricant such as grease is sealed in the space.

The aforementioned seal member generally has a structure having a seal lip which is brought into contact with an appropriate position of a bearing ring different from the bearing ring to which it is attached. The contact mode is such that water and foreign matter are prevented from entering from the outside and leakage of the lubricant inside is allowed. An example of such a sealed thrust ball bearing is U.S. Pat. No. 4,120,543.

[0005]

By the way, the strut suspension device is used in an environment where muddy water is liable to splash, and muddy water is directly splashed also on the sealed thrust ball bearing mounted inside the device. With this, muddy water easily enters the inside of the bearing and the sealing performance is apt to become insufficient.

On the other hand, for example, Japanese Utility Model Laid-Open No. Sho 63-329.
As shown in Japanese Patent Publication No. 96, there is a strut type suspension device provided with a sealing member for protecting a hermetically sealed thrust ball bearing. In this case, considering the entire strut type suspension device, the number of parts used and This is a demerit because it increases the number of assembly steps and increases the cost.

In view of such circumstances, it is an object of the present invention to obtain the same effect as in the case where the seal member is not provided on the bearing mounting target device side.

[0008]

According to the present invention, a plurality of balls are interposed between a pair of two bearing rings formed by press forming from a thin steel plate, and the balls are obliquely contacted with both bearing rings. In addition, the sealed thrust ball bearing, which has a lubricant sealed inside, has the following structure.

The hermetically sealed thrust ball bearing of the present invention is provided with an inner cylindrical portion and an outer cylindrical portion, which extend axially toward the mating bearing ring side, at both inner and outer radial ends of both bearing rings. A seal having, on the inner cylindrical portion of one raceway ring and the outer cylindrical portion of the other raceway ring, a main seal lip that contacts the inner cylindrical portion of the other raceway wheel and the outer cylindrical portion of the one raceway ring, respectively, which are arranged to face them. Members are provided, and in addition to the main seal lip, these seal members project outward in the axial direction from the outer surface of the bearing ring that is the contact partner of the main seal lip, and are components of the bearing installation target device. There is an auxiliary sealing lip which is brought into contact with.

[0010]

According to the present invention, the seal member originally provided in the hermetically sealed thrust ball bearing is provided with the auxiliary seal lip which forms the contact hermetically sealed portion with the components of the bearing mounting target device. By thus improving the seal member mounted on the bearing itself, it becomes unnecessary to provide an extra seal member on the side of the device to which the bearing is attached, unlike the conventional case.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in FIGS. FIG. 1 is a schematic configuration diagram of a sealed thrust ball bearing, FIG. 2 is a sectional view showing a state in which the bearing is incorporated in a strut type suspension device, and FIG. 3 is a sectional view showing a state in which the bearings are stacked.

A in the figure shows the whole of a hermetically sealed thrust ball bearing, 1 is a first annular race, 2 is a second annular race, 3 is a plurality of balls, 4 is a first sealing member, 5 is the second
Is a seal member.

The first annular race 1 has a raceway portion 1a which is curved so as to extend along a portion of the ball 3 which is less than or equal to 1/4, and a raceway portion 1a.
Has an inner cylindrical portion 1b and an outer cylindrical portion 1c that extend in the axial direction from both ends in the radial direction.

The second annular race 2 has a structure which is symmetrical with the first annular race 1 in the radial direction inside and outside, and the ball 1
The track portion 2a is curved so as to follow a portion of / 4 or less, and the inner cylindrical portion 2b and the outer cylindrical portion 2c extend axially from both ends inside and outside of the radial portion of the track portion 2a.

First annular race 1 and second annular race 2
Are arranged so as to face each other in the axial direction, and the inner cylindrical portion 1b of the first annular race 1 and the inner cylindrical portion 2b of the second annular race 2 are radially inward of the group of balls 3 and The outer cylindrical portion 1c of the first annular race 1 and the outer cylindrical portion 2c of the second annular race 2 are located radially outward of the group of balls 3, and the inner cylindrical portion 1b of the first annular race 1 is Radially inward of the inner cylindrical portion 2b of the second annular race 2 and the first annular race 1
The outer cylindrical portion 1c of the outer cylindrical portion 2 of the second annular race 2
They are arranged on the inner side in the radial direction with respect to c. Further, recesses 1d and 2d are provided on the outer surface of the raceway portion 1a of the first annular race 1 near the inner cylindrical portion 1b and on the outer surface of the raceway portion 2a of the second annular race 2 near the outer cylindrical portion 2c. Has been. This recess 1d,
2d is formed by bending the first and second annular races 1 and 2, but may be formed by turning.

The first seal member 4 has a structure in which an elastic body 4b such as rubber is adhered to the outer peripheral surface of a cored bar 4a which is externally fitted and mounted on the inner cylindrical portion 1b of the first annular race 1. An outer main seal lip 4c, which is pressed against the outer surface of the track portion 2a of the second annular race 2, is attached to the body 4b.
The inner main seal lip 4d pressed against the inner peripheral surface of the inner cylindrical portion 2b of the annular race 2, and the bearing attachment target device (strut type suspension device) protruding further outward than the outer surface of the second annular race 2. ) And an auxiliary seal lip 4e which is brought into contact with the appropriate component (upper mount member 6 in FIG. 2) of FIG.

The second seal member 5 has a structure in which an elastic body 5b such as rubber is attached to the inner peripheral surface of a cored bar 5a which is fitted and mounted in the outer cylindrical portion 2c of the second annular race 2. An outer main seal lip 5c, which is brought into pressure contact with the outer surface of the track portion 2a of the first annular race 1, is attached to the elastic body 5b.
Inner seal lip 5d pressed against the outer peripheral surface of the outer cylindrical portion 1c of the annular race 1, and a device to be mounted with a bearing (strut type suspension device) protruding further outward than the outer surface of the first annular race 1. And an auxiliary seal lip 5e which is brought into contact with a suitable component (lower mount member 7 in FIG. 2) of the above.

Although not shown, both annular races 1,
A lubricant such as grease is filled and sealed in a space surrounded by the two raceways 1a, 2a, the outer cylindrical portion 1c of the first annular race 1 and the inner cylindrical portion 2b of the second annular race 2, and a first sealing member. 4 two main seal lips 4c, 4d and a second
The space surrounded by the inner cylindrical portion 2b of the annular race 2 and the second
The space surrounded by the two main seal lips 5c and 5d of the seal member 5 and the outer cylindrical portion 1c of the first annular race 1 is also filled with a lubricant such as grease.

As shown in FIG. 2, the hermetically sealed thrust ball bearing A is mounted between the upper mount member 6 and the lower mount member 7 of the strut type suspension device of the vehicle. In FIG. 2, 8 is a coil spring, and 9 is a piston rod of a shock absorber. In such a usage state, the auxiliary seal lip 4e of the first seal member 4
Is pressed against the inner peripheral surface of the upper mount member 6 and the auxiliary seal lip 5e of the second seal member 5 is pressed against the outer peripheral surface of the lower mount member 7, respectively. , 5 directly on the two main seal lips 4c, 4d, 5c, 5d. These auxiliary seal lips 4e,
5e has a contact form that prevents intrusion of water or foreign matter from the outside and allows leakage of the lubricant inside.

Further, in the sealed thrust ball bearing A, a plurality of sealed thrust ball bearings A can be axially stacked and arranged during transportation or storage as shown in FIG. When stacked in this manner, the auxiliary seal lips 4e and 5e of the first and second seal members 4 are made into the first and second annular races 1 and 2.
The first and second annular races 1 and 2 are set in such a relationship that they enter the concave portions 1d and 2d of the first and second annular races 1 and 2 in a non-contact state so as not to interfere with the. For that purpose, the recess dimensions X1 and X2 of the recesses 1d and 2d of the first and second annular races 1 and 2 are determined by the auxiliary seal lips 4e of the first and second seal members 4 and 5, respectively.
5e is set to be larger than the protruding dimensions Y1 and Y2 from the outer side surfaces of the first and second annular races 1 and 2 to the outside, and the inner diameter dimension Z1 of the auxiliary seal lip 4e of the first seal member 4 is the first. It is larger than the inner diameter Z2 of the annular race 1 and the auxiliary seal lip 5 of the second seal member 5
The outer diameter dimension Z3 of e is set smaller than the outer diameter dimension Z4 of the second annular race 2.

[0021]

According to the present invention, by improving the seal member provided on the bearing itself, it is possible to eliminate the need for providing an extra seal member on the bearing mounting target device side. Therefore, the cost of the entire bearing mounting target device can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of one half of an embodiment of a sealed thrust ball bearing according to the present invention.

FIG. 2 is a sectional view of one half showing a usage state of the bearing.

FIG. 3 is a sectional view of one half showing a stacked state of the bearing.

[Explanation of symbols]

 1 1st annular race 1b Inner cylinder part 1c Outer cylinder part 1d Recessed part 2 2nd annular race 2b Inner cylinder part 2c Outer cylindrical part 2d Recessed part 3 Ball 4 First seal member 4c Outer main seal lip 4d Inner main seal lip 4e auxiliary seal lip 5 second seal member 5c outer main seal lip 5d inner main seal lip 5e auxiliary seal lip

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takunori Shibahara 1 Toyota-cho, Toyota-shi, Aichi Toyota Automobile Co., Ltd.

Claims (1)

[Claims] 1. A plurality of balls are interposed between a pair of two bearing rings formed by press forming from a thin steel plate, the balls are obliquely contacted with both bearing rings, and a lubricant is provided inside. A sealed type thrust ball bearing having a sealed configuration, wherein inner and outer cylindrical portions extending axially toward each other are provided at both inner and outer ends in the radial direction of both bearing rings, respectively. A seal having, on the inner cylindrical portion of one raceway ring and the outer cylindrical portion of the other raceway ring, a main seal lip that contacts the inner cylindrical portion of the other raceway wheel and the outer cylindrical portion of the one raceway ring, respectively, which are arranged to face them. A member is provided, and in addition to the main seal lip, these seal members include
A hermetically sealed type, characterized in that an auxiliary seal lip is provided which projects axially outwardly from the outer surface of the bearing ring which is the contact partner of the main seal lip and is brought into contact with the component parts of the bearing installation target device. Thrust ball bearing.