JP2012026518A - Wave-shaped retainer for ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the performance of preventing wear, burning and damage of the wave-shaped retainer assembled into a ball bearing used with grease lubrication.SOLUTION: A wave-shaped retainer 5 for ball bearing includes a pair of annular retaining pieces 6, 6 and is configured to retain a ball 4 of the ball bearing 1 with a pocket 8 formed by curved parts 6a, 6a opposed to each other in both retaining pieces 6, 6. In the wave-shaped retainer 5 for ball bearing, extension parts 9, extended in an axis direction on the inner circumferential side of the connection parts 6b that connect the curved parts 6a of the respective retaining pieces 6, are provided. Thereby, a decrease of grease accompanied by rotation of the ball bearing 1 that assembles the retainer 5 is suppressed, the lubrication state between the inner surface of the pocket 8 and the ball 4 is satisfactorily maintained for a long period, and the wear of the inner surface of the pocket 8 and the damage of the bearing can be made to hardly occurs.

Description

  The present invention relates to a corrugated cage incorporated in a ball bearing used in grease lubrication.

  In a general deep groove ball bearing, a corrugated cage composed of a pair of annular retaining pieces formed by press forming of a steel plate is often used as a cage for holding a plurality of balls arranged between inner and outer rings. In this corrugated cage, a plurality of bending portions and connecting portions that connect the bending portions are alternately formed in the circumferential direction of each annular holding piece, and the connecting portions are connected in a state where the bending portions of both holding pieces face each other. The balls are held in pockets formed by curved portions facing each other. The inner surface of the pocket is formed in a concave spherical shape having a radius of curvature substantially the same as the radius of the ball.

  By the way, when a corrugated cage as described above is incorporated in a ball bearing used for grease lubrication, the grease filled in the bearing gradually decreases as the bearing rotates, and the cage pocket However, it is difficult for grease to enter between the inner surface and the ball, so the lubrication between the pocket inner surface of the cage and the ball deteriorates during use, causing wear, seizure, and damage to the pocket inner surface. There is a problem of doing.

  On the other hand, it has been proposed that the outer diameter side or inner diameter side of the holding piece bending portion of the corrugated cage is formed substantially parallel to the radial direction so that the lubricant can easily enter the pocket ( (See Patent Document 1).

JP 2002-227844 A (FIG. 5B)

  However, the corrugated cage described in Patent Document 1 cannot cope with a decrease in the amount of grease entering the pocket as the bearing rotates. It is not always satisfactory.

  Therefore, an object of the present invention is to improve the performance of preventing wear, seizure, and damage of a corrugated cage incorporated in a ball bearing used in grease lubrication.

  In order to solve the above problems, the present invention comprises a pair of annular holding pieces, and each holding piece is provided along a plurality of balls arranged between inner and outer rings of a ball bearing used in grease lubrication. The curved portions that are curved and the coupling portions that connect these curved portions are alternately formed in the circumferential direction, and the coupling portions are coupled to each other so that the curved portions of the two holding pieces face each other. In the ball bearing corrugated cage that holds the ball in the pocket formed by the curved portion, at any one of the pair of annular holding pieces, at least one of the inner circumferential side and the outer circumferential side has a shaft A configuration with an overhanging part protruding in the direction was adopted.

  In other words, by providing an axial extension at any position of each holding piece of the corrugated cage to prevent grease flow during rotation of the bearing and make it easier for the grease to remain, the reduction in grease due to rotation of the bearing is suppressed. Thus, the lubrication state between the pocket inner surface and the ball is kept good over a long period of time. The arbitrary positions where the axially extending portions of the holding pieces are provided can be the respective connecting portions or bending portions.

  Here, when providing the said overhang | projection part in the connection part of each holding piece, it makes the overhang | projection part of the connection part incline with respect to an axial direction so that a V-shaped groove may be formed by what mutually opposes. As a result, it is possible to more effectively suppress the decrease in grease accompanying the rotation of the bearing.

  On the other hand, when the protruding portion is provided in the curved portion of each holding piece, by bending the inner peripheral edge of the curved portion in a direction away from the ball as it approaches the axial center, the protruding portion is formed. It becomes easy for grease to enter between the pocket inner surface and the ball, and the lubricity between the cage and the ball can be further improved.

  Moreover, if the circumferential cross-sectional shape of the curved portion of each holding piece is a Gothic arch shape, the grease can be held in the gap between the pocket inner surface and the ball formed at the apex portion of the Gothic arch shape. The lubricity between the vessel and the ball is further improved.

  As the holding piece, one formed by press molding of a metal plate can be used.

  The corrugated cage for ball bearings of the present invention can be applied particularly effectively to a cage incorporated in a ball bearing for an electric vehicle motor.

  As described above, the corrugated cage for a ball bearing according to the present invention is provided with a protruding portion at the connecting portion or the curved portion of the annular retaining piece to reduce the grease as the ball bearing incorporating the cage is rotated. As a result, the lubrication state between the pocket inner surface and the ball is maintained well over a long period of time, and the pocket inner surface is less likely to be worn, seized, or damaged. Therefore, the life of the ball bearing incorporating this cage can be extended.

Longitudinal sectional view of a ball bearing incorporating the cage of the first embodiment (cross section of the retaining piece connecting portion) Front view of the cage of FIG. The arrow view of the principal part seen from the arrow A direction of FIG. FIG. 1 is a cross-sectional view in the circumferential direction of a main part when a modified example of the holding piece bending portion of FIG. Longitudinal sectional view of a ball bearing incorporating the cage of the second embodiment (cross section of the retaining piece connecting portion) Longitudinal sectional view of a ball bearing incorporating the cage of the third embodiment (cross section of the holding piece curved portion) Longitudinal sectional view of a ball bearing incorporating the cage of the fourth embodiment (cross section of the holding piece curved portion)

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a deep groove ball bearing 1 incorporating a corrugated cage 5 for ball bearings according to a first embodiment. This deep groove ball bearing 1 has a plurality of balls 4 arranged between a raceway groove 2a of an inner ring 2 and a raceway groove 3a of an outer ring 3 by a waveform holder 5, and is grease lubricated for an electric vehicle motor. used.

  As shown in FIGS. 1 to 3, the waveform holder 5 is formed by alternately forming curved portions 6 a that are curved along the balls 4 and connecting portions 6 b that connect these curved portions 6 a in the circumferential direction. The pair of annular holding pieces 6 and 6 are connected to each other by a rivet 7 in a state in which the curved portions 6a face each other, and the balls 4 in the pockets 8 formed by the curved portions 6a and 6a facing each other. Is to hold. The inner surface of the pocket 8 is formed in a concave spherical shape having the same radius of curvature as the radius of the ball 4.

  Each holding piece 6 is formed by press forming of a steel plate, and an overhanging portion 9 that projects in the axial direction is provided on the inner peripheral side of the connecting portion 6b. These overhanging portions 9 are inclined with respect to the axial direction so as to form a V-shaped groove between the opposing portions, and the grease flows during rotation of the ball bearing 1 incorporating the cage 5. As a result, the grease can easily remain, so that the reduction of the grease accompanying the rotation of the ball bearing 1 can be effectively suppressed. Moreover, the circumferential direction edge part of each overhang | projection part 9 has extended to the curved part 6a, and it becomes easy to flow in into the pocket 8 from the said V-shaped groove. In addition, as a raw material of each holding piece 6, metal plates other than a steel plate can also be used.

  As described above, the corrugated cage 5 is provided with the axial protruding portion 9 in the connecting portion 6b of each holding piece 6 so that the decrease in grease due to the rotation of the ball bearing 1 can be suppressed. 8 The lubrication state between the inner surface and the ball 4 is maintained well over a long period of time, and wear, seizure, and damage are less likely to occur.

  FIG. 4 shows a modification in which the circumferential cross-sectional shape of the curved portion 6a of each holding piece 6 is a Gothic arch shape. In this modification, the grease is held in the gap between the inner surface of the pocket 8 formed at the apex portion of the gothic arch shape of the holding piece bending portion 6a and the ball 4, so that the lubricity between the cage 5 and the ball 4 is further increased. Can be improved.

  In the second embodiment shown in FIG. 5, an overhanging portion 10 protruding in the axial direction is provided on the outer peripheral side of the connecting portion 6 b of each holding piece 6 in place of the overhanging portion 9 on the inner peripheral side of the first embodiment. Provided. The configuration of the other parts and the point that the decrease in grease accompanying the rotation of the ball bearing 1 can be suppressed by the overhanging portion 10 of each holding piece 6 are the same as in the first embodiment. In addition, although the overhang | projection part 10 of each holding piece 6 is extended substantially parallel to the axial direction, you may make it incline with respect to an axial direction similarly to the overhang | projection part 9 of 1st Embodiment.

  In 3rd Embodiment shown in FIG. 6, it replaces with the overhang | projection parts 9 and 10 of the connection part 6b of each holding piece 6 of 1st, 2nd embodiment, and the outer peripheral side of the curved part 6a of each holding piece 6 is carried out. An overhang portion 11 is provided to project in the axial direction. Even in this case, as in the first and second embodiments, the overhanging portion 11 of each holding piece 6 prevents the grease from flowing during rotation of the ball bearing 1 so that the grease easily remains. Reduction of grease due to rotation can be suppressed.

  In the fourth embodiment shown in FIG. 7, the inner peripheral edge of the bending portion 6a of each holding piece 6 is bent in a direction away from the ball 4 as it approaches the axial center, and the overhanging portion on the outer peripheral side of the third embodiment. An overhanging portion 12 is formed instead of 11. Further, the projecting portion 11 projects so that the gap with the outer peripheral surface of the inner ring 2 is narrower than in the first to third embodiments. As a result, in the same way as in the first to third embodiments, not only the reduction of grease due to rotation of the ball bearing 1 can be suppressed, but also the grease can easily enter between the inner surface of the pocket 8 and the ball 4 and be retained. The lubricity between the vessel 5 and the balls 4 can be further improved.

  The corrugated cage of the present invention is not limited to a ball bearing without a seal structure as in each of the embodiments described above, but can be effectively applied to a ball bearing with a seal structure using a rubber seal, a shield plate, or the like. it can. This is because even a ball bearing having a seal structure cannot completely prevent a decrease in grease during rotation of the bearing, and the suppression of the decrease in grease contributes to a longer life.

DESCRIPTION OF SYMBOLS 1 Ball bearing 2 Inner ring 3 Outer ring 4 Ball 5 Waveform holder 6 Holding piece 6a Curved part 6b Connection part 7 Rivet 8 Pocket 9, 10, 11, 12 Overhang part

Claims (8)

  It consists of a pair of annular holding pieces, and each of these holding pieces connects these curved portions with curved portions that are curved along a plurality of balls arranged between inner and outer rings of a ball bearing used in grease lubrication. The connecting portions are alternately formed in the circumferential direction, the connecting portions are coupled in a state where the curved portions of the two holding pieces face each other, and the balls are held in the pockets formed by the curved portions facing each other. In the ball bearing corrugated cage as described above, at any position of the pair of annular holding pieces, at least one of the inner peripheral side and the outer peripheral side is provided with an overhanging portion protruding in the axial direction. Corrugated cage for ball bearings.   The ball bearing corrugated cage according to claim 1, wherein an arbitrary position of the pair of annular holding pieces is a connecting portion of the holding pieces.   The corrugated ball bearing according to claim 2, wherein the protruding portion of the connecting portion of each holding piece is inclined with respect to the axial direction so as to form a V-shaped groove between the opposing portions. Cage.   The ball bearing corrugated cage according to claim 1, wherein an arbitrary position of the pair of annular holding pieces is a curved portion of each holding piece.   5. The ball bearing waveform holding device according to claim 4, wherein the protruding portion is formed by bending an inner peripheral edge of the curved portion of each holding piece in a direction away from the ball as it approaches the axial center. vessel.   The corrugated cage for ball bearings according to any one of claims 1 to 5, wherein a circumferential cross-sectional shape of the curved portion of each holding piece is a Gothic arch shape.   The corrugated cage for ball bearings according to any one of claims 1 to 6, wherein the holding piece is formed by press forming a metal plate.   8. The ball bearing corrugated cage according to claim 1, which is incorporated in a ball bearing for an electric vehicle motor.

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