JPH08338534A - Sealing device - Google Patents

Abstract

PURPOSE: To facilitate assembling of an outer lip and obtain stable sealability in a device which makes a lip of a seal body be in sliding contact with a slinger fixed to a rotational member for sealing between an unrotational member and the rotational member by so setting a measurement of an inner diameter of the outer lip as to be without contact or in linear contact with the slinger. CONSTITUTION: A sealing device of a water pump bearing for an automobile has a slinger 4 composed of a flange 5 and a cylindrical part 6 fitted and fixed to a pump shaft 1. The cylindrical part 6 is composed of a small diameter cylindrical part 6a closely fitted to the pump shaft 1, and a large diameter cylindrical part 6b arranged substantially parallely to the small diameter cylindrical part 6a without contact to the pump shaft 1, and a tapered stepped portion 6c therebetween. A seal body 7 is arranged between the slinger 4 and a bearing outer ring 2. An inner lip 7a tapered inward is in sliding contact with the small diameter cylindrical part 6a, while an outer lip 7b which is tapered outward without contact or in linear contact to the small diameter cylindrical part 6a is in sliding contact with the large diameter cylindrical part 6b, respectively with specified fastening margins.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device for a water pump bearing for an automobile, for example.

[0002]

2. Description of the Related Art In a conventional sealing device for a water pump bearing for an automobile, for example, as shown in FIG. 3, an outer peripheral part is fixed to an outer ring 101 and an inner peripheral part is obliquely inside a pump shaft 100 and a bearing outer ring 101. After assembling the seal body 102 having the inner lip 103 directed inward and the outer lip 104 directed obliquely inward, a slinger 107 having a substantially L-shaped cross section having a cylindrical portion 105 and a radial flange portion 106 is attached to the pump shaft 100. The inner and outer lips 103, 104 are slidably contacted with the cylindrical portion 105 by pressing and fitting from the outside.

[0003]

In the above-mentioned prior art, the outer lip 104 is generally inclined outward in the opposite direction to the inner lip 103 in order to prevent water outside the bearing from entering the bearing. It is better to point to, but if you do so, problems due to lip reversal at the time of press fitting of the slinger 107 are likely to occur, so you must be very careful in press fitting,
It is troublesome. Therefore, in order to prevent lip reversal, the outer lip 104 is often directed obliquely inward in the same direction as the inner lip 103 as shown in FIG. 3, but in this case, lip reversal can be prevented but external water or the like can be prevented. Problems with the sealing action against intrusion may remain.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems by sliding a lip of a seal member mounted on a non-rotating member to a slinger fixed on the rotating member,
In a sealing device that seals between a non-rotating member and a rotating member,
The slinger has a small-diameter cylindrical portion closely fitted to the rotating member, an inclined step portion that is inclined upward from the small-diameter cylindrical portion toward the non-sealing side and is not in contact with the rotating member, and an axis from the inclined step portion. Direction, a large-diameter cylindrical portion that is substantially parallel to the small-diameter cylindrical portion, and a flange portion that extends radially to the non-rotating member side from the large-diameter cylindrical portion, and the lip of the seal body is inclined toward the sealing side. An outer lip that slidably contacts the small-diameter cylindrical portion of the slinger with a predetermined interference, and an outer lip that inclines toward the non-sealing side and slidably contacts the large-diameter cylindrical portion of the slinger with the predetermined interference. It is characterized in that the inner diameter is formed so as to be in non-contact or light contact with the small-diameter cylindrical portion of the slinger.

[0005]

The seal body is fixed to the non-rotating member, the small-diameter cylindrical portion of the slinger is fitted to the rotating member, and is pressed inward in the axial direction. The inner lip of the seal body that faces inward is in sliding contact with the small diameter part of the slinger cylinder with a specified interference, and the outer lip that faces outward is pushed up along the inclined step and flipped over. Instead, slide it against the large-diameter cylindrical part of the slinger with a predetermined interference.

[0006]

EXAMPLE FIG. 1 shows a sealing device for a water pump bearing for an automobile. Reference numeral 1 is a pump shaft of a water pump for automobiles, and 2 is an outer ring of its bearing, which is fixed to a pump case 3. Reference numeral 4 is a slinger which is fitted and fixed to the pump shaft 1 and includes a flange portion 5 extending in the radial direction and a cylindrical portion 6. The cylindrical portion 6 is a small-diameter cylindrical portion 6a closely fitted to the pump shaft 1, and the small-diameter cylindrical portion 6a.
An inclined step portion 6c which is substantially non-contact with the pump shaft 1 and a large-diameter cylindrical portion 6b which is non-contact with the pump shaft 1 is formed. Reference numeral 7 denotes a seal body disposed between the slinger 4 and the bearing outer ring 2 and the outer peripheral edge thereof is fixed to the bearing outer ring 2. The inner branch is divided into two, and the inner lip 7a inclined inward is directed to the small-diameter cylindrical portion 6a of the cylindrical portion 6, and the outer lip 7b inclined outward is directed to the large-diameter cylindrical portion 6b of the cylindrical portion 6. Each of them is slidably contacted with a predetermined interference for achieving the sealing function.
The inner diameter of the outer lip 7b is set so as to be in non-contact or light contact with the small-diameter cylindrical portion 6a. In addition, the seal body 7
A side lip 7c extending obliquely outward is formed on the outer surface of the, and is slidably contacted with the flange portion 5 with a predetermined interference. Next, the assembly of the sealing device will be described. At the time of assembly, first, the seal body 7 is inserted between the pump shaft 1 and the bearing outer ring 2, and the outer peripheral edge of the seal body 7 is fixed to the groove 2a of the bearing outer ring 2. Then, the slinger 4 fitted to the pump shaft 1 is press-fitted into the seal body 7 side. At this time, since the inner lip 7a faces the inside of the bearing, that is, the assembling direction, there is no fear of reversal. Since the outer lip 7b is opposite to the bearing outer direction, that is, the assembling direction, there is a possibility that the outer lip 7b may be inverted in the conventional structure. The outer lip 7b, which has been inserted, is gradually pushed upward by the inclined step portion 6c and rises along the inclined step portion 6c, so that the outer lip 7b is smoothly pressed against the large-diameter cylindrical portion 6b without being inverted. Sealed. In the embodiment of FIG. 1, the slinger 4 may be press-formed from a plate material, and the large diameter cylindrical portion 6b is formed on a cylindrical surface substantially parallel to the small diameter cylindrical portion 6a, that is, substantially parallel to the axis. , The lip contact pressure can be kept constant regardless of the axial position of the outer lip 7b.

[0007]

As described above, according to the present invention, the outer lip can be assembled so as to surely come into sliding contact with the slinger without being inverted when the slinger is press-fitted, so that the sealing property is stable.

[Brief description of drawings]

FIG. 1 is a front sectional view of an essential part of an embodiment of the present invention.

FIG. 2 is a front cross-sectional view of a main part when a conventional device is assembled.

FIG. 3 is a front cross-sectional view of FIG. 2 when assembled.

[Explanation of symbols] 1 pump shaft 2 bearing outer ring 3 pump case 4 slinger 5 flange part 6 cylindrical part 6a small diameter cylindrical part 6b large diameter cylindrical part 6c inclined step part 7 seal body 7a inner lip 7b outer lip

Claims (1)

[Claims] 1. A sealing device for sealing between a non-rotating member and a rotating member by sliding a lip of a seal body mounted on the non-rotating member to a slinger fixed to the rotating member, wherein the slinger is in close contact with the rotating member. A small-diameter cylindrical portion to be fitted, an inclined step portion that is inclined upward from the small-diameter cylindrical portion toward the non-sealing side and is not in contact with the rotating member, and the small-diameter cylindrical portion that extends in the axial direction from the inclined step portion. It has a substantially parallel large-diameter cylindrical portion and a flange portion that extends in the radial direction from the large-diameter cylindrical portion to the non-rotating member side, and the lip of the seal body is inclined toward the sealing side and is attached to the small-diameter cylindrical portion of the slinger. An inner lip that slidably contacts with a predetermined interference, and an outer lip that is slanted toward the non-sealing side and slidably contacts the large-diameter cylindrical portion of the slinger with a predetermined interference.
A sealing device, characterized in that the inner diameter of the outer lip is formed so as to be in non-contact or light contact with the small-diameter cylindrical portion of the slinger.