JP2005147307A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing 1 with a seal 6, keeping the sealing ability performance with the seal 6 and hardly wearing away even if external pressure is applied thereto. <P>SOLUTION: The outer peripheral edge part of the seal 6 is fitted to the shoulder part of a raceway surface 2 of an outer ring 2 to rock taking the outer peripheral edge part as a fulcrum. The shoulder part of the raceway surface in an inner ring 3 is provided with a sealing groove 8. The inner peripheral edge part of the seal 6 is opposite to the inclined peripheral surface 8b of the sealing groove 8 through a very small gap to form a non-contact sealing part. The axial inside of the inner peripheral edge part of the seal 6 is provided with a radial lip 10 coming into contact with the inclined peripheral surface 8b of the sealing groove 8 in the radial direction. On receiving the external pressure, the sealing 6 is inclined toward the inside of the bearing, but the radial lip 10 smoothly slides on the inclined peripheral surface 8b of the sealing groove 8 to make the contact state steady. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rolling bearing provided with a seal.

A seal used for a rolling bearing is attached so as not to change its posture when pressure is applied from the outside (see, for example, Patent Document 1). The lip of the seal is difficult to bend by increasing the mass as a mass having a substantially trapezoidal cross section. This lip is an axial lip that is brought into contact with the step wall surface along the radial direction in the annular step portion of the inner ring from the axial direction.
No. 6-19859

  In the above conventional example, since the seal lip is an axial lip, if the external pressure is high, the axial lip is strongly pressed against the stepped wall surface of the inner ring and the sealing performance is improved, but it is easily worn when used at high speed rotation. Become.

  The present invention is a rolling bearing in which an annular space between both inner and outer wheels is sealed with a seal attached to opposite shaft ends, and one peripheral edge of the seal is fixed to the shaft end of one wheel, and the other wheel A radial lip that is provided with a seal groove having a shape in which the opposing clearance between the seal and the other peripheral edge of the seal is constant in the swinging direction at the end of the shaft, and is in contact with the seal groove in the radial direction on the inner side in the axial direction of the other peripheral edge. It is characterized by providing.

  In this case, for example, the seal can be tilted inward by receiving external pressure. When the seal is tilted, the radial lip smoothly slides on the seal groove, and the radial lip is in contact with the non-contact sealing portion. The above-mentioned facing clearance that creates the same is almost the same as before the inclination of the seal. Therefore, the wear progress of the radial lip is suppressed while ensuring the sealing performance by the seal.

  The seal groove is constituted by a stepped wall surface along the radial direction and an inclined peripheral surface extending from the step wall surface side toward the edge side, and a cross-sectional shape along the axial direction of the inclined peripheral surface is defined from the one peripheral edge side of the seal. It can be made into the substantially same shape as the circular arc which makes the length to a radial lip side the curvature radius. In this case, even when the seal is tilted inward of the bearing, the contact state between the lip and the inclined circumferential surface having the arc-shaped cross section and the clearance of the non-contact sealing portion do not change from those before the tilt. Therefore, the sealing performance by the seal is stabilized and the progress of wear of the radial lip is suppressed.

  The radial lip may have a tapered shape inclined obliquely inward toward the inside of the bearing, and the inner peripheral portion of the distal end of the radial lip may be in contact with the seal groove.

  The rolling bearing of the present invention can contribute to the improvement of reliability because it maintains the sealing property of the seal and is less likely to wear even when used in an environment that receives external pressure.

  The best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing the main part of a rolling bearing with a seal, FIG. 2 is a diagram showing the movement of the seal in FIG. 1, and FIG. 3 is a diagram showing a usage situation of the rolling bearing in FIG.

  The illustrated rolling bearing 1 is a deep groove type ball bearing, and includes an outer ring 2, an inner ring 3, a rolling element 4, and a cage 5, and one axis of an opposing annular space between the outer ring 2 and the inner ring 3. A seal 6 is provided to seal the end.

  On one shoulder portion of the raceway surface of the outer ring 2, a seal fixing portion 7 having an annular stepped structure that expands in diameter is provided. The seal fixing portion 7 includes a stepped wall surface 7a along the radial direction and a groove-shaped peripheral surface 7b recessed outward in the radial direction.

  A seal groove 8 having an annular stepped structure having a reduced diameter is provided on one shoulder on the raceway surface of the inner ring 3. The seal groove 8 has a stepped wall surface 8a along the radial direction, and an inclined peripheral surface 8b that gradually decreases in diameter from the stepped wall surface 8a side toward the edge side.

  The seal 6 has a configuration in which a radial lip 10 is attached to the inner peripheral side of an annular cored bar 9 made of metal or the like. A portion from the outer peripheral edge of the annular core 9 to the inner peripheral edge through the outer surface is covered with an elastic material such as thin rubber. The annular metal core 9 is bent so that the outer peripheral side and the inner peripheral side thereof are stepped in the axial direction. The radial lip 10 extends in an obliquely inward direction from the inner side surface of the inner peripheral edge of the annular core 9 and has a tapered shape.

  The seal 6 is attached by engaging the outer peripheral edge portion of the annular core metal 9 with the groove-shaped peripheral surface 7 b of the seal fixing portion 7 of the outer ring 2, and the inner peripheral edge of the annular core metal 9 is the seal of the inner ring 3. The groove 8 is opposed to the inclined peripheral surface 8b through a minute gap so as to form a non-contact sealing portion 11. The radial lip 10 is in contact with the radial direction in the middle of the inclined circumferential surface 8b of the seal groove 8 of the inner ring 3 in the axial direction.

  The cross-sectional shape of the inclined peripheral surface 8 b in the seal groove 8 of the inner ring 3 is an arc shape having a curvature radius R as a length L from the outer peripheral edge side of the seal 6 to the radial lip side.

  With this configuration, the seal 6 can be tilted with the point X of the outer peripheral edge of the seal fixing portion 7 as a fulcrum, and when the seal 6 is tilted inward of the bearing, the radial lip 10 is 3 smoothly slides on the inclined peripheral surface 8b of the seal groove 8. As a result, as shown in FIG. 2, even when the seal 6 is inclined inward by receiving the external pressure P, the contact state between the radial lip 10 and the inclined peripheral surface 8b of the seal groove 8 and the non-contact sealing portion The clearance of 11 remains the same as before the tilt. Therefore, the sealing performance by the seal 6 is stabilized, and the progress of wear of the radial lip 10 can be suppressed. When the seal 6 is tilted inward of the bearing, the tilt fulcrum is not specified at the point X in the figure, and may deviate from the point X in the seal fixing portion 7.

  For these reasons, even under conditions where pressure acts on the seal 6 from the outside of the rolling bearing 1, the seal 6 can be sealed and the wear of the radial lip 10 can be suppressed, improving reliability. Can contribute.

  By the way, the rolling bearing 1 with the seal 6 described above is incorporated into a transmission such as a motorcycle, for example, as shown in FIG.

  In FIG. 3, 30 is a case, 31 is an axle drive shaft, and as indicated by an arrow, lubricating oil from an oil pump (not shown) is supplied to an oil supply path 32 formed in the case 30 and a side space 33 of the rolling bearing 1. The oil is supplied to the gear inner through an oil passage 34 and an oil passage 35 formed in the axle drive shaft 31.

  In such a structure, the pressure when supplying the lubricating oil acts on the seal 6 mounted on the rolling bearing 1, but the seal 6 is configured as described above. Even if it receives, the seal | sticker 6 will be hold | maintained substantially stationary, and durability can be improved after ensuring the sealing performance as designed.

  Further, the inclined peripheral surface 8b of the seal groove 8 of the inner ring 3 can be a linear inclined peripheral surface as shown in FIG. 4, for example. Also in this case, when the seal 6 is tilted inward of the bearing, the radial lip 10 slides smoothly on the inclined peripheral surface 8b in the seal groove 8 of the inner ring 3, and the contact state of the radial lip 10 and the non-contact sealing portion 11 The clearance is almost the same as that before the seal 6 is tilted. Therefore, almost the same as in the embodiment shown in FIG. 1, the sealing performance by the seal 6 can be secured and the progress of wear of the radial lip 10 can be suppressed.

  For example, as shown in FIG. 5, the seal 6 is provided with an annular portion 9a extending axially inward of the bearing on the outer peripheral portion of the annular core 9 and elastic such as rubber on the outer periphery and inner end face of the annular portion 9a. It may be a material coated. In this case, when the seal 6 is inclined inward of the bearing, for example, the position of the point X becomes a fulcrum. Also in this case, the position that becomes the fulcrum of the tilt of the seal 6 is not specified at the point X in the figure, and may deviate from the point X in the seal fixing portion 7.

  Further, although not shown, the seal 6 may be attached to the inner ring 3 side and the radial lip 10 may be brought into contact with the outer ring 2 side. In this case, the groove-like peripheral surface 7b of the seal fixing portion 7 of the outer ring 2 is shaped like the inclined peripheral surface 8b in the inner ring 3 of FIGS. 1 and 4, and the radial lip 10 of the seal 6 is formed on the inclined peripheral surface 7b. Make contact from the direction.

Sectional drawing which shows the principal part of the rolling bearing with a seal concerning one embodiment of the present invention. The figure which shows the motion of the seal | sticker of FIG. The figure which shows the use condition of the rolling bearing of FIG. Sectional drawing which shows the principal part of the rolling bearing with a seal which concerns on other embodiment of this invention. Sectional drawing which shows the principal part of the rolling bearing with a seal concerning other embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rolling bearing 2 Outer ring 3 Inner ring 6 Seal 7 Seal fixing | fixed part 8 Seal groove 8a Step wall surface 8b Inclined circumferential surface 9 Annular core 10 Radial lip

Claims (3)

A rolling bearing in which the annular space between the inner and outer wheels is sealed with a seal attached to the opposite shaft ends,
One seal peripheral edge is fixed to the shaft end of one wheel, and a seal groove having a shape that makes the clearance facing the other peripheral edge of the seal constant in the swinging direction is provided at the shaft end of the other wheel, A rolling bearing characterized in that a radial lip that comes into contact with the seal groove in the radial direction is provided on the inner side in the axial direction of the other peripheral edge.   The seal groove is constituted by a stepped wall surface along the radial direction and an inclined peripheral surface extending from the step wall surface side toward the edge side, and a cross-sectional shape along the axial direction of the inclined peripheral surface is defined from the one peripheral edge side of the seal. The rolling bearing according to claim 1, wherein the curved bearing is substantially the same curved surface as an arc having a radius of curvature up to the radial lip side.   The rolling bearing according to claim 1 or 2, wherein the radial lip is tapered inwardly toward the inside of the bearing, and an inner peripheral portion of the tip thereof is brought into contact with the seal groove.

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