JP2017215020A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing which has high sealing performance with an inexpensive structure, and a long life, as compared with a conventional rolling bearing.SOLUTION: A rolling bearing has an outer ring 120; an inner ring 130; a plurality of rolling elements 140; a pair of seal members 150; and a pair of slingers 160. Each slinger is composed of a grease guiding surface 165 for guiding a grease, an annular portion 161 having a back surface of the grease guiding surface which is a sliding surface 164 sliding with a main lip of the seal member, and a cylinder portion 162 extending from an inner diameter side end of the annular portion to the sliding surface side, and formed with an elastic body layer on an inner peripheral surface. The slinger is fitted and fixed to an outer peripheral surface of the inner ring so as to turn the grease guiding surface 165 to the inside in an axial direction, while the elastic body layer is elastically deformed. On a sliding surface of the slinger, the main lip 155 of the seal member slides from the outside in the axial direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rolling bearing, and more particularly to an improvement of a rolling bearing in which grease is sealed with a seal member.

As a conventional grease lubricated rolling bearing, one having a seal member that seals between an outer ring and an inner ring is known (see, for example, Patent Documents 1 and 2). FIG. 2 shows a longitudinal sectional view of an essential part of an example of such a rolling bearing. The rolling bearing 10 includes an outer ring 20, an inner ring 30, a plurality of balls 40 that are rolling elements, a retainer 45, and a pair of seal members (only one is shown).

An outer ring raceway surface 21 that defines the outer ring raceway groove of the ball 40 is formed on the inner circumferential surface of the outer ring 20, and an inner ring raceway surface 31 that defines the inner ring raceway groove of the ball 40 is formed on the outer circumferential surface of the inner ring 30. ing. Between the outer ring raceway surface 21 and the inner ring raceway surface 31, a plurality of balls 40 that are arranged at equal intervals in the circumferential direction by a cage 45 and that are rotatably held are arranged. A pair of seal members 50 disposed on both sides of the ball 40 between the outer ring 20 and the inner ring 30 seals the annular space between the inner peripheral surface of the outer ring 20 and the outer peripheral surface of the inner ring 30 and encloses the annular ring in the annular space. In addition to preventing leaked grease (not shown) from leaking to the outside, foreign substances (for example, water, muddy water, dust, etc.) are prevented from entering the annular space.

The outer peripheral surface of the inner ring 30 includes an inner ring raceway surface 31, a cylindrical surface 32 positioned on both sides in the axial direction of the inner ring raceway surface 31, and seal groove portions 33 at both ends on the axial direction outside of the cylindrical surface 32. The seal groove 33 includes a small-diameter cylindrical surface 34 having a smaller diameter than the cylindrical surface 32, and a wall surface 35 that connects the small-diameter cylindrical surface 34 and the cylindrical surface 32.

Each seal member 50 includes a cored bar 51 in which a metal plate such as a steel plate is formed in an annular shape, and an elastic member 52 fixed to the cored bar 51. The elastic member 52 covers an outer peripheral edge of the cored bar 51, and an outer peripheral part 53 formed to protrude slightly outward in the radial direction, and a neck part 54 extending radially inward from the inner peripheral edge of the cored bar 51. And a main lip 55 extending inward in the axial direction from the tip of the neck portion 54, and an auxiliary lip 56 protruding from the inner peripheral edge of the cored bar 51 inward in the radial direction and inward in the axial direction. The outer peripheral edge 53 of the elastic member 52 is locked by press-fitting or the like into a locking groove 22 formed at the axial end of the outer ring 20 to fix the seal member 50 to the outer ring 20.

The main lip 55 is in sliding contact with the wall surface 35 of the seal groove 33 formed at the axial end of the inner ring 30 to constitute a contact-type seal. Further, the auxiliary lip 56 constitutes a labyrinth seal by being close to the cylindrical surface 32 in the vicinity of the wall surface 35 of the seal groove portion 33 to prevent leakage of grease to the outside.

JP 2002-130305 A JP 2008-175312 A

However, since the wall surface 35 of the seal groove portion 33 with which the main lip 55 of the seal member 50 is slidably contacted is formed by machining such as lathe processing, it is difficult to increase the surface roughness at a low cost. Depending on the application, sufficient performance may not be obtained with respect to sealing performance and seal life. In order to increase the surface roughness, costly processing such as grinding the seal groove was required. Further, in the labyrinth seal by the auxiliary lip 56, it is difficult to prevent the grease leaking from the gap when the grease inside the bearing moves outward in the axial direction.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a rolling bearing that has a low-cost configuration, high sealing performance, and a long service life as compared with conventional rolling bearings.

The above object of the present invention can be achieved by the following constitution. An outer ring having an outer ring raceway surface on an inner peripheral surface, an inner ring having an inner ring raceway surface on an outer peripheral surface, a plurality of rolling elements arranged to be rollable between the outer ring raceway surface and the inner ring raceway surface, A rolling bearing comprising a pair of seal members fixed to an outer ring, further comprising a pair of slinger, each slinger having a grease guiding surface for guiding grease and a back surface of the grease guiding surface being the seal An annular part that is a sliding contact surface with which the main lip of the member is slidably contacted, and a cylindrical part that extends from the inner diameter side end of the annular part to the sliding contact surface side and has an elastic layer formed on the inner peripheral surface. The slinger is fitted and fixed to the outer peripheral surface of the inner ring so that the grease guiding surface faces inward in the axial direction in a state where the elastic layer is elastically deformed, and the sealer is attached to the sliding surface of the slinger. The lip of the member is in sliding contact from the outside in the axial direction Rolling bearing characterized by

According to the present invention, the lip of the sealing member is not slidably contacted with a cutting surface such as a lathe as in the prior art, but is slidably contacted with a sliding surface of a slinger that is a metal press surface having a high surface roughness. The performance can be improved, the wear of the main lip can be suppressed, and the durability life can be extended. This eliminates the need for costly grinding processes and eliminates the need for processing the previously required seal grooves, thereby improving the sealing performance at low cost and extending the durability of the main lip. . In addition, since the slinger is fitted and fixed to the inner ring through the elastically deformed elastic body layer, the press-fitting portion is in close contact, and the slinger and inner ring are fitted even on the outer peripheral surface of the inner ring having a rough surface. Grease does not leak from the joint gap, and foreign matter does not enter the bearing. Further, in the conventional configuration, there is a possibility that the grease inside the bearing leaks outside through the labyrinth gap between the auxiliary lip 56 and the cylindrical surface 32 of the inner ring 30. However, in this configuration, the grease inside the bearing is leaked outside the bearing inner ring. When moving to the outside in the axial direction, the grease is guided radially outward by the grease guiding surface of the ring portion of the slinger that is in close contact with the outer peripheral surface of the inner ring. And when the rolling bearing is operated, it is sent to the outer ring side by centrifugal force, so there is no risk of the grease leaking to the outside, and the grease circulates smoothly without stagnation, and the grease is efficiently circulated. The bearing life can be extended compared with the conventional case.

It is principal part sectional drawing explaining one Embodiment of the rolling bearing which concerns on this invention. It is a principal part longitudinal cross-sectional view explaining an example of the rolling bearing of a prior art.

Hereinafter, an embodiment of a rolling bearing according to the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the rolling bearing 110 of the present embodiment includes an outer ring 120, an inner ring 130, a plurality of balls 140 that are rolling elements, a cage 145, and a pair of seal members (only one is shown in the figure). .) 150 and a pair of slinger (only one is shown in the figure) 160.

An outer ring raceway surface 121 that defines an outer ring raceway groove of the ball 140 is formed on the inner peripheral surface of the outer ring 120, and an inner ring raceway surface 131 that defines an inner ring raceway groove of the ball 140 is formed on the outer peripheral surface of the inner ring 130. ing. Between the outer ring raceway surface 121 and the inner ring raceway surface 131, a plurality of balls 140 that are arranged at equal intervals in the circumferential direction by a cage 145 and are held so as to be able to roll are arranged. A pair of seal members 150 and a pair of slinger 160 disposed on both sides of the ball 140 between the outer ring 120 and the inner ring 130 seal an annular space between the inner peripheral surface of the outer ring 120 and the outer peripheral surface of the inner ring 130. Prevents grease (not shown) enclosed in the annular space from leaking to the outside and prevents foreign substances (eg, water, muddy water, dust, etc.) from entering the annular space. To do.

The outer circumferential surface of the inner ring 130 includes an inner ring raceway surface 131 and cylindrical surfaces 132 positioned on both sides in the axial direction of the inner ring raceway surface 131, and has a cylindrical shape with the same diameter except for the inner ring raceway surface 131.

Each slinger 160 is formed by pressing a metal plate such as a steel plate into a substantially L-shaped cross section including an annular portion 161 and a cylindrical portion 162 extending in the axial direction from the inner diameter side end of the annular portion 161. is there. A surface of the annular portion 161 on the cylindrical portion 162 side is a slidable contact surface 164 with which the main lip 155 of the seal member 150 is slidably contacted. Further, the back surface of the sliding contact surface 164 serves as a grease guiding surface 165 for efficiently circulating the grease inside the bearing. On the inner peripheral surface of the cylindrical portion 162 of the slinger 160, an elastic body layer 163 such as rubber is formed by a known technique such as coating or vulcanization without interruption in the circumferential direction. The inner diameter of the elastic body layer 163 is slightly smaller than the cylindrical surface 132 of the inner ring 130, and the slinger 160 elastically deforms the elastic body layer 163, and the annular portion 161 is axially inner than the cylindrical portion 162. In other words, the grease guide surface 165 is fitted and fixed to the cylindrical surface 132 of the inner ring 130 so that the sliding contact surface 164 faces the outside in the axial direction.

Each seal member 150 includes a metal core 151 in which a metal plate such as a steel plate is formed in an annular shape, and an elastic member 152 fixed to the metal core 151. The elastic member 152 includes an outer peripheral edge portion 153 that covers the outer peripheral edge of the core metal 151 and projects slightly outward in the radial direction, and a neck portion 154 that extends radially inward from the inner peripheral edge of the core metal 151. And a main lip 155 extending inward in the axial direction from the tip of the neck portion 154, and an auxiliary lip 156 protruding from the inner peripheral edge of the cored bar 151 in the radial direction and in the axial direction. The outer peripheral edge 153 of the elastic member 152 is locked by press-fitting or the like into a locking groove 122 formed at the axial end of the outer ring 120 to fix the seal member 150 to the outer ring 120.

The main lip 155 is in sliding contact with the sliding contact portion 164 of the annular portion 161 of the slinger 160 from the outside in the axial direction to constitute a contact type seal. Further, the auxiliary lip 156 constitutes a labyrinth seal by being close to the outer peripheral edge of the annular portion 161 of the slinger 160, thereby preventing leakage of grease to the outside.

By adopting the configuration as described above, the main lip 155 does not slide on the cutting surface of a lathe or the like as in the prior art, but slides on the sliding surface 164 of the slinger 160 which is a metal press surface with high surface roughness. By contacting, the sealing performance can be improved and the durable life of the main lip 155 can be extended. This eliminates the need for a costly grinding process and eliminates the need for machining the sealing groove that was required in the past, so that the sealing performance can be improved at low cost and the durability of the main lip 155 can be extended. it can. In addition, since the slinger 160 is fitted and fixed to the inner ring 130 via the elastically deformed elastic body layer 163, the press-fitting portion is in close contact with the cylindrical surface 132 of the inner ring 130 having a rough surface. Grease does not leak from the fitting gap between the slinger 160 and the inner ring 130, and foreign matter from the outside does not enter the bearing.

Further, in the conventional configuration, there is a possibility that the grease inside the bearing leaks outside through the labyrinth gap between the auxiliary lip 56 and the cylindrical surface 32 of the inner ring 30. However, in this configuration, the grease inside the bearing is leaked outside the bearing inner ring. When moving to the outside in the axial direction, the grease is guided radially outward by the grease guiding surface 165 of the annular portion 161 of the slinger 160 in close contact with the cylindrical surface 132. When the inner ring 130 of the rolling bearing 110 rotates, it is sent to the outer ring side by centrifugal force. Therefore, there is no possibility that the grease leaks to the outside, and the grease circulates smoothly without stagnation and efficiently grease. Can be supplied to the raceway surfaces 121 and 131, and the bearing life can be extended as compared with the prior art.

In addition, this invention is not limited to what was illustrated to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably. For example, in the above embodiment, the case where the present invention is applied to the ball bearing is illustrated, but the present invention is not limited to this, and the present invention is applied to other types of rolling bearings such as a tapered roller bearing, a cylindrical roller bearing, and a needle roller bearing. May be. In the above embodiment, the case where the present invention is applied to a single row rolling bearing is illustrated, but the present invention is not limited to this, and the present invention is applied to a double row rolling bearing or a multi-row rolling bearing having three or more rows. May be.

DESCRIPTION OF SYMBOLS 10 Rolling bearing 20 Outer ring 21 Outer ring raceway surface 22 Locking groove 30 Inner ring 31 Inner ring raceway surface 32 Cylindrical surface 33 Sealing groove part 34 Small diameter cylindrical surface 35 Wall surface 40 Ball 45 Cage 50 Seal member 51 Core metal 52 Elastic member 53 Outer peripheral edge part 54 Neck portion 55 Main lip 56 Auxiliary lip 110 Rolling bearing 120 Outer ring 121 Outer ring raceway surface 122 Locking groove 130 Inner ring 131 Inner ring raceway surface 132 Cylindrical surface 140 Ball 145 Cage 150 Seal member 151 Core metal 152 Elastic member 153 Outer peripheral edge portion 154 Neck portion 155 Main lip 156 Auxiliary lip 160 Slinger 161 Ring portion 162 Cylindrical portion 163 Elastic layer 164 Sliding surface 165 Grease guiding surface

Claims (1)

An outer ring having an outer ring raceway surface on an inner peripheral surface, an inner ring having an inner ring raceway surface on an outer peripheral surface, a plurality of rolling elements arranged to be rollable between the outer ring raceway surface and the inner ring raceway surface, A rolling bearing comprising a pair of seal members fixed to an outer ring, further comprising a pair of slinger, each slinger having a grease guiding surface for guiding grease and a back surface of the grease guiding surface being the seal An annular part that is a sliding contact surface with which the main lip of the member is slidably contacted, and a cylindrical part that extends from the inner diameter side end of the annular part to the sliding contact surface side and has an elastic layer formed on the inner peripheral surface. The slinger is fitted and fixed to the outer peripheral surface of the inner ring so that the grease guiding surface faces inward in the axial direction in a state where the elastic layer is elastically deformed, and the sealer is attached to the sliding surface of the slinger. The main lip of the member is in sliding contact from the outside in the axial direction Rolling bearing according to claim.

Images