JP2525865Y2 - Rolling bearing sealing device - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is a sealing device for a rolling bearing provided with an axial groove for ventilation to cope with fluctuations in the internal pressure of the bearing caused by a temperature change inside the bearing. About.

(Prior art) In a rolling bearing, a change in internal pressure occurs due to an increase or decrease in temperature inside the bearing during rotation, and as a result, the seal lip swells and comes off or curves inward, thereby causing an external bearing to rotate. Dust may intrude from there, and the sealing performance may be degraded. In order to solve such a problem, various devices have been devised which enable a respiratory action with the outside.

Among them, for example, a sealing device for a rolling bearing shown in FIGS. 7 and 8 of Japanese Utility Model Application Laid-Open No. 1-158824 discloses an annular groove provided at an inner peripheral end of an outer ring. Is mounted, an annular passage is formed between the outer peripheral edge of the seal plate and the annular groove, and the lip formed on the inner peripheral edge of the seal plate is brought into sliding contact with the outer peripheral edge of the inner ring, and the seal is formed. The annular groove is communicated with the outside of the bearing through the axial groove provided on the outer peripheral edge of the plate, and further, the inside of the bearing and the annular groove are communicated inside the outer peripheral edge of the seal plate. It is provided with a radial groove, and is adapted to a pressure change generated inside the bearing.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional product, the radial groove provided inside the seal plate is in close contact with the wall surface of the annular groove of the outer ring. (The linear expansion coefficient is equivalent to 10 times that of iron.)

(Means for Solving the Problems) The present invention has been made to solve such a problem, and an outer peripheral edge of a seal plate is attached to an annular groove provided at an inner peripheral end of an outer ring. An annular passage is formed between the outer peripheral edge of the seal plate and the annular groove, and a lip formed on the inner peripheral edge of the seal plate is slidably contacted with the outer peripheral edge of the inner ring; A radial groove for communicating the outside of the bearing with the annular groove through the axial groove, and further communicating the inside of the bearing with the annular groove on the inner side of the outer peripheral edge of the seal plate. The present invention relates to a sealing device for a rolling bearing, characterized in that an inclined groove whose extension line does not pass through the center of the bearing is provided instead of the radial groove.

(Operation) The inner oblique groove of the seal plate is formed so that its extension line is oblique so that it does not pass through the center of the bearing, so the oblique groove is longer than the force that crushes the radial groove of the seal. As a result, stress concentration is reduced, and the degree of oblique grooves is reduced.

(Example) Next, an example of this invention is described based on a drawing. FIG. 1 shows a main part of a ball bearing incorporating a sealing device according to the present invention. The ball bearing has an outer ring 1 provided with an annular groove 6 at an inner peripheral end, and a V-shape at an outer peripheral end. A steel ball 4 rotatably incorporated between an inner race provided with an annular groove having a cross-sectional shape of a circle and a raceway 8 formed on an inner peripheral surface of the outer race and a raceway 9 formed on an outer peripheral surface of the inner race. And a seal plate 3 having an outer peripheral edge mounted in an annular groove of the outer ring. Reference numeral 5 denotes a retainer for disposing the steel balls 4 at predetermined intervals.

The seal plate 3 is made of rubber in which a metal core 10 is embedded, and an outer peripheral edge 11 is mounted in the annular groove 6 of the outer race 1, and an annular passage 14 is formed between the annular groove and the outer peripheral edge of the seal plate. . Further, an axial groove 12 is provided on an outer peripheral edge portion 11 of the seal plate,
As shown in FIG. 2, at a position 180 degrees in the circumferential direction from the axial groove 12, the inside of the bearing and the annular passage 14 communicate with the inside of the outer peripheral edge, and an extension of An oblique groove 13 that does not pass through the center is provided. A lip 15 is provided on the inner peripheral edge of the seal plate 3, and the lip is in sliding contact with the wall surface 16 of the annular groove 7 of the inner ring 2.

As shown in FIG. 1, the inclined groove 13 is in close contact with the wall surface 17 forming the annular groove 6 of the outer ring, and tends to crush the radial groove due to the thermal expansion coefficient of the rubber of the seal. Since the oblique grooves 13 communicating with the inside are formed longer than conventional products, stress concentration is reduced, and the oblique grooves 13 are less likely to be compressed and crushed. Further, since the oblique groove 13 is located at a position 180 degrees in the circumferential direction with respect to the axial groove 12, foreign matter such as dust invading from the outside passes through the annular passage 14 when passing through the annular passage 14. And entering the bearing through the oblique groove 13 is reduced.

Further, the sealing device according to the present invention can be used for a bearing for an automobile transmission. These types of bearings have recently been required not only to withstand high loads and high temperatures with the increase in engine output, but also to have a long life in oil containing abrasion powder from peripheral parts. It goes without saying that the above requirements can be satisfied by using the invented sealing device for the above-mentioned bearing for automobiles.

(Effect) In the present invention, as described above, the oblique groove is formed with respect to the axial groove, and the inside of the bearing and the annular passage are communicated with each other. Oblique grooves are rarely crushed. For this reason, the inside and outside of the bearing always communicate with each other, and the respiratory action is not impaired.

In addition, since the oblique grooves and the axial grooves are located 180 degrees apart in the circumferential direction, even if dust or the like enters, they pass through the annular passage connecting them, and they are stopped in the annular passage. , Thereby preventing intrusion into the bearing.
In addition, stable sealing performance can be maintained even when used in oil containing dust and the like.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of a ball bearing to which the sealing device of the present invention is attached, and FIG. 2 is a front view of the sealing device as viewed from the direction of arrow A in FIG. 1 ... Outer ring, 2 ... Inner ring, 3 ... Seal plate, 4 ... Steel ball, 6 ... Outer ring annular groove, 7 ... Inner ring annular groove, 8 ...
Track of outer ring 9 Track of inner ring 11 Peripheral edge of seal plate 12 Axial groove 13 Oblique groove 14 Ring path 16 Inner wall wall 17 ... the outer ring wall.

Claims (2)

(57) [Scope of request for utility model registration] An outer peripheral edge of a seal plate is mounted in an annular groove provided at an inner peripheral end of an outer ring, an annular passage is provided between the outer peripheral edge of the seal plate and the annular groove, and the seal is provided. The lip formed on the inner peripheral edge of the plate is brought into sliding contact with the outer peripheral edge of the inner ring, and an axial groove is provided on the outer peripheral edge of the seal plate to communicate the outside of the bearing with the annular groove via the axial groove. Further, in a rolling bearing sealing device provided with a radial groove communicating the inside of the bearing and the annular groove on the inner side of the outer peripheral edge of the seal plate, an extension line of the groove instead of the radial groove. A sealing device for a rolling bearing, characterized in that an inclined groove that does not pass through the center of the bearing is provided. 2. The rolling bearing sealing device according to claim 1, wherein said oblique groove is located at a position of about 180 ° in a circumferential direction with respect to said axial groove.