JP2012031914A - Retainer for ball bearing and the ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce torque caused by the shearing resistance of a lubricant easily.SOLUTION: A crown-shaped retainer 5 for a ball bearing includes a main part 5a which has a ring shape; and a plurality of pairs of claws 5b which are spaced from one another in a circumferential direction of axially one side of the main part 5a and axially projected. The retainer further includes a concave pocket 5c which is recessed between the respective pair of the claws 5b and opened at outer and inner diameter sides. The pocket 5c freely and rotatably holds a ball 4. Edges 5d and 5e of the pocket 5c are made to be scraping mechanisms for scraping the lubricant by line contact with the ball 4.

Description

  The present invention relates to a ball bearing cage made of synthetic resin that holds a ball so as to roll freely, and a ball bearing in which the cage is incorporated between an outer ring and an inner ring.

  As rolling bearings incorporated in automobile electrical parts and auxiliary parts such as fan coupling devices, alternators, idler pulleys, car air conditioner electromagnetic clutches, electric fan motors, etc., the rotating shaft that is driven to rotate by the engine output is used as a stationary member. Sealed ball bearings such as deep groove ball bearings and angular contact ball bearings are widely used to support them rotatably.

  This type of ball bearing includes an inner ring having an inner raceway formed on the outer peripheral surface, an outer ring disposed outside the inner ring and having an outer raceway formed on the inner peripheral surface, and an inner raceway surface of the inner ring. A plurality of balls interposed between the outer ring and the outer raceway surface of the outer ring, a cage disposed between the inner ring and the outer ring, and holding the balls at equal intervals in the circumferential direction, and the inner ring The main part is composed of an annular space formed between the outer rings and a seal portion that seals the annular space.

  In this ball bearing, either the outer ring or the inner ring is mounted on a stationary member such as a housing, and the other is mounted on a rotating shaft that is driven to rotate by engine output. In addition, a lubricant such as grease is sealed in an annular space between the inner and outer rings so that the balls roll smoothly in the pocket of the cage.

  Various cages whose shapes are symmetrical in the axial direction have been proposed as cages incorporated in the ball bearings (see, for example, Patent Documents 1 and 2). The cages disclosed in these Patent Documents 1 and 2 form hemispherical pockets for accommodating balls on the opposing surfaces of the two annular bodies facing in the axial direction at a plurality of locations in the circumferential direction, A structure in which two annular bodies are joined by rivets between adjacent pockets by abutting the opposing surfaces.

JP 9-317775 A JP 2003-13962 A

  In recent years, in ball bearings for automobiles, a reduction in torque has been demanded from environmental problems such as improved fuel consumption. Of the torque in this type of ball bearing, the torque generated between the cage and the ball is dominated by the shear resistance of a lubricant such as grease by the cage.

  Incidentally, the cages disclosed in Patent Documents 1 and 2 described above have a structure in which a recess is formed in the pocket and the recess functions as a lubricant reservoir. In this way, the concave portion functions as a lubricant reservoir, thereby improving the lubrication state between the cage and the ball, improving the bearing performance and extending the life of the bearing.

  However, in the cages disclosed in these Patent Documents 1 and 2, since the pocket recess functions as a lubricant reservoir as described above, if the amount of lubricant enclosed in the ball bearing increases, the pocket recess Lubricant tends to accumulate. As a result, the shearing resistance of the lubricant increases, and it becomes difficult to reduce the torque generated between the cage and the balls due to the shearing resistance of the lubricant.

  Therefore, the present invention has been proposed in view of the above-mentioned problems, and the object of the present invention is to provide a ball bearing retainer and a ball bearing that can easily reduce the torque caused by the shear resistance of the lubricant. It is to provide.

  As a technical means for achieving the above-mentioned object, the present invention includes a main part having an annular shape and a plurality of axially projecting projections spaced apart from each other in the circumferential direction of one axial surface of the main part. A crown-shaped ball consisting of a pair of claws, with a concave pocket that is recessed between each pair of claws and opens to the outer diameter side and the inner diameter side, and holds the ball in such a manner that it can roll freely. The bearing cage is characterized in that the edge portion of the pocket is a scraping mechanism for scraping the lubricant by line contact with the ball. In addition, it is effective that the main part and the claw part in the present invention are made of synthetic resin in that the weight of the cage can be reduced. Here, the “edge portion” of the pocket means a boundary portion between the outer diameter surface or inner diameter surface of the main portion and the claw portion and the inner surface of the pocket adjacent thereto.

  In the present invention, the scraping mechanism provided at the edge portion of the pocket exhibits a function of scraping the lubricant by line contact with the ball rolling in the pocket. Thereby, the excess lubricant existing between the pocket and the ball can be quickly removed. As a result, the shear resistance of the lubricant can be reduced, and the torque generated between the cage and the ball can be easily reduced by the shear resistance of the lubricant.

  The scraping mechanism in the present invention is preferably only the claw portion of the edge portion of the pocket. Thus, if only the claw portion at the edge portion of the pocket is used as the scraping mechanism, it is possible to prevent the lubricant from being scraped excessively and becoming insufficient. In the present invention, not only the claw portion at the edge portion of the pocket is used as the scraping mechanism, but the entire edge portion of the pocket may be used as the scraping mechanism.

  The scraping mechanism in the present invention preferably has a structure that is an outer diameter side edge portion of the pocket. In this way, surplus lubricant can be removed by scraping the lubricant at the outer edge of the pocket. This scraping mechanism can be an edge portion on the inner diameter side of the pocket. In this case, excess lubricant can be removed by scraping the lubricant at the inner diameter side edge portion of the pocket. Further, the scraping mechanism may be both an outer diameter side edge portion and an inner diameter side edge portion of the pocket. In this way, excess lubricant can be more effectively removed by scraping the lubricant at the outer diameter side edge portion and the inner diameter side edge portion of the pocket.

  In the present invention, a structure in which a main portion is provided with a reduced thickness portion that becomes a lubricant reservoir is desirable. In this way, the volume of the annular space formed between the inner and outer rings of the ball bearing can be increased, and lubricant leakage due to an increase in the internal pressure of the ball bearing can be suppressed. The thinned portion can be formed on either the outer diameter side or the inner diameter side of the main portion, and if formed on both the outer diameter side and the inner diameter side of the main portion, the lubricant leakage is further reduced. It can suppress more effectively.

  The cage having the above configuration is arranged in an outer ring and an inner ring that rotate relative to each other, a ball that is interposed between the outer ring and the inner ring, and an annular space formed between the outer ring and the inner ring, and the annular space is sealed. If a sealing part to be added is added, a sealed ball bearing can be configured.

  According to the present invention, the edge portion of the pocket as the scraping mechanism is present between the pocket and the ball by exhibiting a function of scraping the lubricant by line contact with the ball rolling in the pocket. Excess lubricant can be quickly removed. As a result, the shear resistance of the lubricant can be reduced, and the torque generated between the cage and the ball can be easily reduced by the shear resistance of the lubricant. As a result, it is possible to easily provide a ball bearing for automobiles that is suitable for environmental problems such as fuel efficiency improvement in recent years.

In embodiment of this invention, (A) is a top view which shows the crown shaped holder | retainer which accommodated the ball | bowl in the pocket, (B) is sectional drawing which follows the AA line of (A). In embodiment of this invention, it is a partial expansion perspective view which shows the holder | retainer which used both the outer diameter side edge part and inner diameter side edge part of the pocket as a scraping mechanism. In other embodiment of this invention, it is a partial expansion perspective view which shows the holder | retainer which used only the outer diameter side edge part of the pocket as the scraping mechanism. In other embodiment of this invention, it is a partial expansion perspective view which shows the holder | retainer which used only the inner diameter side edge part of the pocket as the scraping mechanism. In other embodiment of this invention, it is a partial expansion perspective view which shows the holder | retainer which used only the nail | claw part of both the outer diameter side edge part and inner diameter side edge part of a pocket as a scraping mechanism. In other embodiment of this invention, it is a partial expansion perspective view which shows the holder | retainer which provided the thinning part in both the outer-diameter side and inner-diameter side of the main part. In other embodiment of this invention, it is the elements on larger scale which show the holder | retainer which provided the thinning part only in the outer diameter side of the main part. In other embodiment of this invention, it is a partial expansion perspective view which shows the holder | retainer which provided the thinning part only in the internal diameter side of the main part. In each embodiment of the present invention, it is a partial sectional view showing a sealed ball bearing incorporating a cage.

  Embodiments of a ball bearing retainer and a ball bearing according to the present invention will be described in detail below. In the following embodiments, a rotating shaft that is incorporated in an electrical component or auxiliary component of an automobile, such as a fan coupling device, an alternator, an idler pulley, an electromagnetic clutch for a car air conditioner, an electric fan motor, and the like, and is driven to rotate by an engine output Sealed ball bearings such as deep groove ball bearings and angular contact ball bearings that are rotatably supported on a stationary member are illustrated.

  As shown in FIG. 9, the ball bearing 1 of this embodiment is arranged on the outer periphery of an inner ring 2 having an inner rolling surface 2 a formed on the outer peripheral surface, and on the outer peripheral surface 3 a on the inner peripheral surface. Between the inner ring 2 and the outer ring 3, between the inner ring 2 and the outer ring 3, between the inner ring 2 and the outer ring 3, the inner ring 2 and the outer ring 3. Is formed between the inner ring 2 and the outer ring 3, and is disposed on both sides in the axial direction between the inner ring 2 and the outer ring 3. The main part is composed of the seal part 6 that seals the annular space 7. By enclosing a lubricant such as grease in the annular space 7 sealed by the seal portion 6, the ball 4 rolls smoothly in the pocket of the cage 5.

  In this embodiment, the outer ring 3 is mounted on a stationary member such as a housing, and the inner ring 2 is mounted on a rotating shaft that is driven to rotate by engine output. The seal portion 6 includes a cored bar 6a attached to an inner diameter end of the outer ring 3 on the fixed side, and a seal member 6b integrally vulcanized and bonded to the cored bar 6a. The seal member 6b is a rubber member. It has a sealing lip 6c that contacts the outer diameter end of the inner ring 2 at its tip. In this embodiment, the inner ring rotating type is illustrated, but the present invention can also be applied to an outer ring rotating type in which the inner ring 2 is mounted on a stationary member such as a housing and the outer ring 3 is mounted on a rotating shaft.

  During the operation of the ball bearing 1, the inner ring 2 rotates while maintaining the state in which the seal lip 6 c at the tip of the seal member 6 b is in sliding contact with the outer peripheral end of the inner ring 2. This prevents foreign matters such as water and dust from entering the inside of the bearing or leakage of the lubricant from the inside of the bearing to the outside.

  The crown-shaped cage 5 disposed between the inner ring 2 and the outer ring 3 of the ball bearing 1 having the above-described configuration is a main ring having an annular shape as shown in FIGS. Each pair of claw portions, each of which is composed of a plurality of claw portions 5b that are integrally spaced in the axial direction and spaced apart from each other at equal intervals in the circumferential direction of one axial surface of the main portion 5a. A concave pocket 5c is provided between the outer diameter side and the inner diameter side. The ball 5 is rotatably held in the pocket 5c. In the cage 5 having the above-described configuration, the edge portions 5d and 5e of the pocket 5c, that is, the boundary portion between the outer diameter surface 5h or the inner diameter surface 5i of the main portion 5a and the claw portion 5b and the inner surface 5j of the pocket 5c adjacent thereto. Is a scraping mechanism for scraping the lubricant by line contact with the balls 4.

  In the embodiment shown in FIGS. 1A and 1B and FIG. 2, the case where both the outer diameter side edge portion 5d and the inner diameter side edge portion 5e of the pocket 5c are used as a scraping mechanism is illustrated. In this scraping mechanism, the outer radius side edge portion 5d and the inner radius side edge portion 5e are formed by making the curvature radius of the outer diameter side and inner diameter side of the inner surface 5j of the pocket 5c smaller than the curvature radius of the outer spherical surface of the ball 4. The ball 4 is brought into contact with the ball 4 by line contact.

  In this embodiment, the case where both the outer diameter side edge portion 5d and the inner diameter side edge portion 5e of the pocket 5c are scraped mechanisms is illustrated, but as shown in FIG. 3, the outer diameter of the pocket 5c is illustrated. Only the side edge portion 5d may be a scraping mechanism. In this case, by making the curvature radius on the outer diameter side of the inner surface 5j of the pocket 5c smaller than the curvature radius of the outer spherical surface of the ball 4, only the outer diameter side edge portion 5d is brought into contact with the ball 4 by line contact. The curvature radius other than the outer diameter side of the inner surface 5j of 5c may be equal to the curvature radius of the outer spherical surface of the ball 4.

  Moreover, as shown in FIG. 4, it is good also considering only the inner diameter side edge part 5e of the pocket 5c as a scraping mechanism. In this case, by making the curvature radius on the inner diameter side of the inner surface 5j of the pocket 5c smaller than the curvature radius of the outer spherical surface of the ball 4, only the inner diameter side edge portion 5e is brought into contact with the ball 4 by line contact, and the pocket 5c The radius of curvature other than the inner diameter side of the inner surface 5j may be made equal to the radius of curvature of the outer spherical surface of the ball 4.

  In the embodiments shown in FIGS. 2 to 4, the outer diameter side edge portion 5d or the inner diameter side edge portion 5e is exemplified as a scraping mechanism over the entire circumference of the outer diameter surface 5h or the inner diameter surface 5i. However, as shown in FIG. 5, only the outer diameter side edge portion 5d of the pocket 5c and the claw portion 5b of the inner diameter side edge portion 5e may function as a scraping mechanism. In this case, the outer radius side edge portion 5d and the inner diameter side edge portion 5e are formed by making the curvature radius of the outer diameter side and the inner diameter side of the claw portion 5b of the inner surface 5j of the pocket 5c smaller than the curvature radius of the outer spherical surface of the ball 4. If the nail | claw part 5b is contact | abutted to the ball 4 by line contact, and the curvature radius other than the outer-diameter side and inner-diameter side of the nail | claw part 5b of the inner surface 5j of the pocket 5c is made equivalent to the curvature radius of the outer spherical surface of the ball | bowl 4 Good.

  In the embodiment shown in FIG. 5, the case where both the claw portions 5b of the outer diameter side edge portion 5d and the inner diameter side edge portion 5e of the pocket 5c are functioned as a scraping mechanism is illustrated in FIG. Similarly to the illustrated embodiment, only the claw portion 5b of the outer diameter side edge portion 5d of the pocket 5c may function as a scraping mechanism. In this case, the radius of curvature on the outer diameter side of the claw portion 5b of the inner surface 5j of the pocket 5c is made smaller than the curvature radius of the outer spherical surface of the ball 4, so that the claw portion 5b of the outer diameter side edge portion 5d is lined with the ball 4. The radius of curvature other than the outer diameter side of the claw portion 5b of the inner surface 5j of the pocket 5c may be made equal to the radius of curvature of the outer spherical surface of the ball 4 by contact.

  Further, as in the embodiment shown in FIG. 4, only the claw portion 5b of the inner diameter side edge portion 5e of the pocket 5c may function as a scraping mechanism. In this case, by making the radius of curvature of the claw portion 5b of the inner surface 5j of the pocket 5c smaller than the radius of curvature of the outer spherical surface of the ball 4, the claw portion 5b of the inner diameter side edge portion 5e can be brought into line contact with the ball 4. The curvature radius other than the inner diameter side of the claw portion 5b of the inner surface 5j of the pocket 5c may be made equal to the curvature radius of the outer spherical surface of the ball 4.

  In each of the embodiments described above, the edge portions 5d and 5e of the pocket 5c serving as a scraping mechanism exhibit a function of scraping the lubricant by line contact with the balls 4 that roll in the pocket 5c. Thereby, the excess lubricant which exists between the pocket 5c and the ball | bowl 4 can be removed rapidly. As a result, the shear resistance of the lubricant can be reduced, and the torque generated between the cage 5 and the balls 4 can be easily reduced by the shear resistance of the lubricant.

  In particular, when both the outer diameter side edge portion 5d and the inner diameter side edge portion 5e of the pocket 5c are used as a scraping mechanism, the function of scraping the lubricant is sufficiently exhibited. Further, when only the claw portions 5b of the edge portions 5d and 5e of the pocket 5c are used as the scraping mechanism, it is possible to prevent the lubricant from being scraped excessively and becoming insufficient.

  The embodiment shown in FIGS. 6 to 8 exemplifies a structure in which the main portion 5a of the cage 5 is provided with the thinned portions 5f and 5g serving as lubricant reservoirs. The thinned portions 5f and 5g can be formed by cutting after the cage 5 is manufactured by injection molding, and can also be formed simultaneously with the cage 5 being manufactured by injection molding. Thus, by forming the thinned portions 5f and 5g by cutting or injection molding, the thinned portions 5f and 5g can be easily formed, and the cost can be reduced.

  In the embodiment shown in FIG. 6, the case where the thinned portions 5f and 5g are formed on both the outer diameter side and the inner diameter side of the main portion 5a is illustrated. Moreover, in embodiment shown in FIG. 7, the case where the thinning part 5f is formed only in the outer diameter side of the main part 5a is illustrated. Furthermore, in the embodiment shown in FIG. 8, the case where the thinned portion 5g is formed only on the inner diameter side of the main portion 5a is illustrated.

  Thus, by providing the main portion 5a of the cage 5 with the reduced thickness portions 5f and 5g serving as lubricant reservoirs, the annular space 7 formed between the inner ring 2 and the outer ring 3 of the ball bearing 1 (FIG. 9). ) And the leakage of the lubricant from the seal portion 6 due to an increase in the internal pressure of the ball bearing 1 can be suppressed. In particular, as in the embodiment of FIG. 6, when the thinned portions 5 f and 5 g are provided on both the outer diameter side and the inner diameter side of the main portion 5 a, the volume of the annular space 7 can be greatly increased. And leakage of the lubricant can be reliably suppressed.

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. It includes the equivalent meanings recited in the claims and the equivalents recited in the claims, and all modifications within the scope.

DESCRIPTION OF SYMBOLS 1 Ball bearing 2 Inner ring 3 Outer ring 4 Ball 5 Cage 5a Main part 5b Claw part 5c Pocket 5d Outer diameter side edge part 5e Inner diameter side edge part 5f, 5g Thinning part

Claims (11)

  An annular main portion and a plurality of pairs of claw portions protruding in the axial direction at intervals in the circumferential direction of one axial surface of the main portion, and recessed between each pair of claw portions A crown-shaped ball bearing retainer that has a concave pocket that is open on the outer diameter side and the inner diameter side, and that holds the ball in a freely rolling manner in the pocket, the edge of the pocket being the ball A ball bearing retainer characterized by a scraping mechanism that scrapes off the lubricant by line contact with the bearing.   2. The ball bearing retainer according to claim 1, wherein the scraping mechanism is only a claw portion of an edge portion of a pocket.   The ball bearing retainer according to claim 1 or 2, wherein the scraping mechanism is an outer diameter side edge portion of a pocket.   The ball bearing retainer according to claim 1, wherein the scraping mechanism is an inner diameter side edge portion of a pocket.   The ball bearing retainer according to claim 1 or 2, wherein the scraping mechanism is both an outer diameter side edge portion and an inner diameter side edge portion of the pocket.   The ball bearing retainer according to any one of claims 1 to 5, wherein the main portion is provided with a reduced thickness portion that serves as a lubricant reservoir.   The ball bearing retainer according to claim 6, wherein the thinned portion is formed on an outer diameter side of the main portion.   The ball bearing retainer according to claim 6, wherein the thinned portion is formed on an inner diameter side of the main portion.   The ball bearing retainer according to claim 6, wherein the thinned portion is formed on both an outer diameter side and an inner diameter side of the main portion.   The ball bearing retainer according to any one of claims 1 to 9, wherein the main portion and the claw portion are made of synthetic resin.   The retainer according to any one of claims 1 to 10, an outer ring and an inner ring rotating relative to each other, and a ball interposed between the outer ring and the inner ring, and formed between the outer ring and the inner ring. A ball bearing having a seal portion arranged in an annular space and sealing the annular space.

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