JP2012077761A - Thrust ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrust ball bearing capable of achieving a small size and a light weight by reducing a width in radial direction compared with a roller, and achieving a low torque by holding a rolling body in one side or both sides.SOLUTION: The thrust ball bearing includes raceway rings (an outer diameter raceway ring 2 and an inner diameter raceway ring 4), a plurality of balls 6 and a retainer 8. The raceway rings include: annular raceway flat portions (an outer diameter-side flat portion 2a and an inner diameter-side flat portion 4a) where raceway faces (an outer diameter-side raceway face 2s and an inner diameter-side raceway face 4s) are formed; and cylindrical portions (an outer diameter-side cylindrical portion 2b and an inner diameter-side cylindrical portion 4b) axially extending from circumference edge portions of the raceway flat portions. The retainer includes an annular retainer flat portion 8a having an outer diameter smaller than the inner diameter of the outer diameter-side cylindrical portion and having an inner diameter larger than the outer diameter of the inner diameter-side cylindrical portion, and a plurality of windows 80. An extended circumference edge is protruding each of the outer diameter-side cylindrical portion and the inner diameter-side cylindrical portion so as to form a projection (an outer diameter-side projection 2c and an inner diameter-side projection 4c) that can engage with circumference edges (outer circumference edge 8b and an inner periphery edge 8c) of the retainer flat portion. Thereby, the raceway rings, the retainer and balls can be rotated relative to one another and are integrated as inseparable.

Description

  The present invention relates to a thrust bearing, specifically, a thrust ball bearing mainly used for an air conditioner compressor, a torque converter, a transmission and the like of an automobile.

  Conventionally, various rolling bearings have been used to rotatably support a predetermined rotating shaft, and the bearing types of the rolling bearings can be roughly classified into radial bearings and thrust bearings depending on the direction of the load to be applied. Further, it can be classified as a ball bearing or a bearing according to the type of rolling element. For example, a thrust roller bearing is mounted on a rotating portion of an air conditioner compressor, torque converter, or transmission of an automobile, and an axial axial load (thrust load) applied to the rotating portion is loaded (see Patent Documents 1 to 3). ). FIG. 9 shows an example of the configuration of the thrust roller bearing.

By the way, in recent years, as environmental problems such as global warming have become more serious, demands for miniaturization, weight reduction and torque reduction of thrust bearings for automobiles have become strict, and price competitiveness has been secured. There is also a strong demand for lowering the cost (in short, reducing the unit price of bearings and increasing the efficiency of assembly).
As measures to meet such demands, the roller diameter (dimension D shown in FIG. 9) and the roller length (dimension L) are shortened to reduce the size and weight of the bearing and reduce the number of built-in rollers. To reduce torque, etc., which may lead to a reduction in bearing unit price. Further, by integrating the bearing rings (outer diameter bearing ring 32 and inner diameter bearing ring 34) and the C & R assembly (the assembly of the cage 38 and 36) in a non-separable manner, the assembly at the customer is improved, Cost reduction can be achieved. At that time, by omitting the bearing ring (outer diameter bearing ring 32 or inner diameter bearing ring 34), it is possible to further narrow the axial width of the bearing, but on the other hand, the counterpart member on which the bearing is mounted. In some cases, the rolling part or the like of the roller needs to be separately processed such as polishing. In this case, the cost is increased.

Japanese Utility Model Publication No. 7-12627 JP 2002-213439 A JP-A-10-159842

However, when the roller length L is shortened and the ratio of the roller length L to the roller diameter D (roller length L / roller diameter D) is 1.5 or less, it is necessary to change the manufacturing method of the roller itself and, consequently, the entire bearing. In some cases, there is a problem that the cost is increased as a result. Alternatively, if the number of built-in rollers is reduced, it becomes inevitable that the area of the flat portion of the cage 38 becomes larger (wider) than the area of the window portion. Therefore, for example, in a metal cage, if the number of built-in rollers is reduced too much, the area of the cage plane portion becomes excessive compared to the window area, so that problems such as warp deformation during heat treatment of the cage are caused. It becomes easy to cause.
In order to reduce the torque, it is also effective to adopt a cage configuration (so-called roller holding cage) in which the cage is held only by the roller during rotation of the bearing and does not contact the raceway. Since the height of the cage (dimension H shown in FIG. 9) decreases as the diameter decreases, it is actually not easy to achieve the rolling. In this case, it is conceivable to achieve roller holding by adjusting the dimensions of the cage window part, but depending on the processing accuracy of the window part, the roller is constrained, resulting in smooth rolling of the roller. May interfere.

  The present invention has been made to solve such problems, and its purpose is to shorten the radial width of the bearing (ratio of outside diameter of bearing) compared to the case where the same diameter and the same number of rollers are used. This makes it possible to reduce the size and weight of the bearing, and to allow the cage to hold the ball in a non-contact state with the bearing ring (providing rolling elements on one or both sides) to reduce the bearing torque. It is to provide a bearing.

  In order to achieve such an object, a thrust ball bearing according to the present invention includes at least one bearing ring having a raceway surface, and a plurality of balls arranged along the circumferential direction with respect to the raceway surface, A cage that holds the ball in a freely rolling manner, and the race ring extends from the outer peripheral edge of the race flat plate portion to one side in the axial direction. It has either an outer diameter side cylindrical portion that protrudes or an inner diameter side cylindrical portion that extends from the inner peripheral edge of the flat plate portion to the other side in the axial direction, and the retainer has an outer diameter on the outer diameter side Smaller than the inner diameter of the cylindrical portion, or the inner diameter is larger than the outer diameter of the inner diameter side cylindrical portion, or the outer diameter is smaller than the inner diameter of the outer diameter side cylindrical portion, and the inner diameter is An annular retainer plate portion set larger than the outer diameter of the inner diameter side cylindrical portion, and the retainer A plurality of window portions for holding the balls are formed in the circumferential direction with respect to the plate portion, and the extended peripheral end portion projects in the reduced diameter direction on the outer diameter side cylindrical portion. And an outer diameter side protruding portion engageable with the outer peripheral edge portion of the retainer flat plate portion is provided, and the extending peripheral end portion is protruded in the diameter increasing direction on the inner diameter side cylindrical portion, An inner diameter side protruding portion that can be engaged with an inner peripheral edge portion of the retainer flat plate portion is provided, and the raceway, the retainer, and the ball can be rotated relative to each other and integrated in a non-separable manner. ing.

  In this case, the window portion of the cage is reduced in diameter with respect to the central portion in the axial direction so that the opening peripheral edge on one side or both sides in the axial direction is smaller than the diameter of the ball, and rolls the ball. It is configured to hold it freely and not to drop off.

  According to the present invention, compared to the case where the same diameter and the same number of rollers are used, the radial width of the bearing (ratio of bearing outer diameter size) can be shortened, and the bearing can be reduced in size and weight. . Further, the ball can be held by the cage in a non-contact state with the raceway, that is, the cage can be provided with rolling elements on one side or both sides, and the torque of the bearing can be reduced.

It is principal part sectional drawing which shows the structure of the thrust ball bearing which concerns on 1st Embodiment of this invention. It is principal part sectional drawing which shows the structure of the thrust ball bearing which concerns on 2nd Embodiment of this invention. It is principal part sectional drawing which shows the structure of the thrust ball bearing which concerns on 3rd Embodiment of this invention. It is principal part sectional drawing which shows the structure of the thrust ball bearing which concerns on 4th Embodiment of this invention. It is a figure which shows the structure of the thrust ball bearing which concerns on 5th Embodiment of this invention, Comprising: (a) is the important point of the bearing which made the ball | bowl arrange | positioned in two rows so that two PCD may be made to hold on one side with a holder | retainer. (B) is a cross-sectional view of the main part of a bearing in which balls arranged in two rows so as to form two PCDs are held on both sides by a cage, and (c) is a view of the opening peripheral edge of the cage window It is a principal part top view which shows a structure. It is a figure which shows the structure of the thrust ball bearing which concerns on 6th Embodiment of this invention, Comprising: (a) is a principal part cross section of the bearing which made the ball | bowl disperse | distributed so that different PCD might be made to have both sides with a holder | retainer FIG. 4B is a plan view of the main part showing the configuration of the opening periphery of the cage window. It is a figure which shows the comparison result of the bearing size and dynamic torque of the thrust ball bearing and thrust roller bearing which concern on one Embodiment (1st Embodiment) of this invention. It is a figure for demonstrating the structural conditions of the holder | retainer of the thrust ball bearing used for the comparison with the thrust roller bearing shown in FIG. It is principal part sectional drawing which shows the structure of the conventional thrust roller bearing.

  Hereinafter, a thrust ball bearing (hereinafter also simply referred to as a bearing) of the present invention will be described with reference to the accompanying drawings. The thrust ball bearing according to the present invention is mounted mainly on a rotating part of an automotive air conditioner compressor, torque converter, transmission, etc., and is used to apply an axial axial load (thrust load) applied to the rotating part. However, the application is not limited to this. At that time, the bearing is preferably lubricated in order to reduce friction, wear, prevention of seizure, or extension of fatigue life at the portions where the race, rolling element (ball), and cage are in contact with each other. . In the present embodiment, it is assumed as an example that oil lubrication (for example, sealing of lubricating oil inside the bearing, etc.) superior in fluidity of the lubricant and cooling effect on the bearing is performed as compared with grease lubrication. However, it is also possible to assume grease lubrication (for example, sealing grease inside the bearing).

(First embodiment)
FIG. 1 shows the configuration of a thrust ball bearing according to the first embodiment of the present invention. Such a bearing includes at least one bearing ring having a raceway surface, a plurality of balls arranged along the circumferential direction with respect to the raceway surface, and a cage that holds the balls in a freely rolling manner. Yes. In this case, if at least one bearing ring is provided, a bearing can be formed. In this embodiment, however, the two bearing rings 2 and 4 can be rotated relative to each other as shown in FIG. It is assumed that the bearings are arranged opposite to each other. However, as in a third embodiment (FIG. 3) and a fourth embodiment (FIG. 4) of the present invention which will be described later, it is possible to adopt a bearing configuration having only one bearing ring.

Of the two race rings, a race ring (hereinafter, referred to as an outer diameter race ring) 2 disposed on one side in the axial direction (as an example, the left side in FIG. 1) is a race surface (also referred to as an outer diameter side race face). ) An annular track flat plate portion 2a formed with 2s (referred to as an outer diameter side plane portion) 2a and the other side in the axial direction from the outer peripheral edge portion of the outer diameter side plane portion 2a (for example, the right side of FIG. ) Has an outer diameter side cylindrical portion 2b extending at a substantially right angle to the outer circumference.
On the other hand, of the two race rings, a race ring (hereinafter referred to as an inner diameter race ring) 4 arranged on the other side in the axial direction (as an example, the right side in FIG. 1) An annular track flat plate portion (referred to as an inner diameter side plane portion) 4a formed with 4s and one axial side from the inner peripheral edge portion of the inner diameter side plane portion 4a (for example, the left side of FIG. ) Has an inner diameter side cylindrical portion 4b extending at a substantially right angle.

  In this case, both the outer diameter raceway ring 2 and the inner diameter raceway ring 4 are processed by pressing a thin plate material (for example, a plate thickness of about 0.5 mm to 1.0 mm) (for example, pressing or bending). It is molded so as to form a substantially L-shape. The outer diameter raceway ring 2 and the inner diameter raceway ring 4 are configured such that the outer diameter side plane portion 2a and the inner diameter side plane portion 4a, more specifically, the outer diameter side raceway surface 2s and the inner diameter side raceway surface 4s face each other. The outer diameter side cylindrical portion 2b is arranged on the outer diameter side (upper side in FIG. 1), and the inner diameter side cylindrical portion 4b is arranged on the inner diameter side (same as the lower side), and assembled so as to form a substantially rectangular shape in cross section (see FIG. 1).

  The size (diameter (ball diameter)), the number of incorporation (number of arrangements), and the like of the balls 6 as rolling elements can be arbitrarily set. In the present embodiment, about 22 to 40 balls 6 whose diameter (ball diameter) is set to about 1.5 mm to 2.5 mm have outer circumferential surfaces (rolling surfaces) as outer diameter side raceways. 2s and the inner raceway surface 4s are abutted with each other in a space (a rolling space) between the raceways 2s and 4s at a predetermined interval (for example, an equal interval) in the circumferential direction. The case (single row arrangement forming a single pitch circle diameter (PCD)) is assumed as an example. Note that the configurations of the outer diameter raceway ring 2 and the inner diameter raceway ring 4, for example, the radial width of the outer diameter side plane portion 2 a and the inner diameter side plane portion 4 a, and the axial direction of the outer diameter side cylindrical portion 2 b and the inner diameter side cylindrical portion 4 b. The length may be set according to the diameter and number of balls 6 arranged in the rolling space. Further, the extension angle of the outer diameter side cylindrical portion 2b with respect to the outer diameter side plane portion 2a and the extension angle of the inner diameter side cylindrical portion 4b with respect to the inner diameter side plane portion 4a are not particularly limited.

  The cage 8 has an outer diameter smaller than the inner diameter of the outer diameter side cylindrical portion 2 b of the outer diameter raceway ring 2 and an inner diameter larger than the outer diameter of the inner diameter side cylindrical portion 4 b of the inner diameter raceway ring 4. An annular flat plate portion (hereinafter referred to as a cage flat plate portion) 8a set to the above and a plurality of window portions 80 for holding the balls 6 that are perforated along the circumferential direction of the cage flat plate portion 8a. And have. The cage 8 inserts the balls 6 into the respective window portions 80 and holds the balls 6 between the outer diameter raceway ring 2 and the inner diameter raceway ring 4, specifically, the outer diameter side raceway surface 2s and the inner diameter. It is assembled into the rolling space between the side raceway surfaces 4s. Thus, in a state where the cage 8 is assembled to the rolling space, the cage flat plate portion 8a does not come into contact with either the outer diameter side cylindrical portion 2b or the inner diameter side cylindrical portion 4b, and a predetermined gap is provided therebetween. It is empty. Note that the cage 8 is made of a plate material (for example, press working or punching) that is thinner than the outer diameter raceway ring 2 and the inner diameter raceway ring 4 (for example, a plate thickness of about 0.3 mm to 0.5 mm). Thus, it is formed into a substantially annular flat plate shape.

The window portion 80 of the cage 8 is located with respect to the central portion in the axial direction so that the opening peripheral edge on one side or both sides in the axial direction (left-right direction in FIG. 1) is smaller than the diameter (ball diameter) of the ball 6. The ball 6 is reduced in diameter and holds the ball 6 so that it can roll and cannot fall off. In the present embodiment, as shown in FIG. 1, the opening peripheral edge 80a on one side (left side in the figure) of the window portion 80 is axially extended until its opening diameter is slightly smaller than the ball diameter. The diameter of the central portion (hereinafter referred to as the axially central portion) 80b is reduced, and the retainer 8 (in short, the window portion 80) holds the ball 6 inserted into the window portion 80 so that it can roll and cannot fall off. A configuration (so-called one-side rolling element) is assumed as an example. In other words, the cage 8 holds the ball 6 in the window portion 80 so that it can roll and cannot fall off by causing the ball 6 inserted into the window portion 80 to interfere with the opening peripheral edge 80a.
The opening peripheral edge 80c of the window 80 on the opposite side to the opening peripheral edge 80a (the right side in FIG. 1) has a larger diameter than the axial central part 80b, and the opening diameter is slightly smaller than the ball diameter. Is set to large. That is, the window portion 80 has a tapered shape (so-called frustoconical through-hole) in which the peripheral surface area gradually increases in diameter from the opening peripheral edge 80a to the opening peripheral edge 80c through the axial central portion 80b. At this time, the taper angle of the window 80 (inclination angle α shown in FIG. 8) may be set to about 30 ° to 50 °, but is not particularly limited. Moreover, what is necessary is just to perform the insertion of the ball | bowl 6 to the window part 80 from the opening periphery 80c.

  Even if the cage 8 is made of metal, the cage 8 is made by punching the tapered window portion 80 into such a single plate material. While it can be set as the structure which has a one-side rolling element, the deformation | transformation at the time of heat processing can be suppressed reliably. Even if the cage 8 is thermally deformed, the shape of the cage 8 can be easily corrected by, for example, a press temper.

  In the present embodiment, the outer peripheral side end portion of the outer raceway ring 2 has an extended peripheral end projecting in the diameter reducing direction (downward in FIG. 1), and the outer peripheral edge of the retainer flat plate portion 8a. A projecting portion (hereinafter referred to as an outer diameter projecting portion) 2c that can be engaged with the portion 8b is provided. On the other hand, the extending peripheral end of the inner diameter side cylindrical portion 4b of the inner diameter raceway ring 4 protrudes in the diameter increasing direction (upward in FIG. 1), and the inner peripheral edge portion 8c of the cage flat plate portion 8a Engageable protrusions (hereinafter referred to as “inner diameter side protrusions”) 4 c are provided. The outer diameter side protruding portion 2c engages with the outer peripheral edge portion 8b of the retainer flat plate portion 8a when the outer diameter raceway ring 2 is displaced in the axial direction (leftward in FIG. 1). As long as excessive pressing force is not applied, the projection form (projection length, projection range, etc.) is set so as to maintain the interference state with the outer peripheral edge 8b and prevent further displacement in the axial direction. do it. Similarly, when the inner diameter side raceway 4 is displaced in the axial direction (rightward in FIG. 1), the inner diameter side protruding portion 4c interferes with and engages with the inner peripheral edge portion 8c of the cage flat plate portion 8a. As long as excessive pressing force is not applied, the projection form (projection length, projection range, etc.) is set so as to maintain the interference state with the inner peripheral edge 8c and prevent further displacement in the axial direction. do it. FIG. 1 also shows an outer diameter side protruding portion 2c and an inner diameter side protruding portion 4c formed by continuously projecting the extended peripheral ends of the outer diameter side cylindrical portion 2b and the inner diameter side cylindrical portion 4b over the entire circumference. However, for example, it is also possible to adopt a configuration in which only one portion of the extended peripheral end portions of the cylindrical portions 2b and 4b, or only a few portions in the circumferential direction are protruded. .

  As described above, the outer diameter side cylindrical portion 2b of the outer diameter raceway ring 2 is provided with the outer diameter side protruding portion 2c, and the inner diameter side cylindrical portion 4b of the inner diameter raceway ring 4 is provided with the inner diameter side protruding portion 4c. When the ring 2 and the inner raceway ring 4, the cage 8 and the ball 6 are assembled, the raceways 2 and 4 and the assembly (assembly) of the cage 8 and the ball 6 can be rotated relative to each other. And they can be integrated in a non-separable manner.

  Here, a comparison was made between the bearing size and dynamic torque of a thrust ball bearing according to the present embodiment (hereinafter referred to as the present bearing) and a thrust roller bearing using rollers as rolling elements (hereinafter referred to as a comparative bearing). At that time, the same number of rolling elements (balls or rollers) with the same diameter (three types of diameters: 1.5 mm, 2.0 mm, and 2.5 mm) (22 types, 30 types, 3 types of 40 units) and the same plate It is held by a cage having three thicknesses (0.3 mm, 0.4 mm, and 0.5 mm, dimension t1 shown in FIG. 8), and these are held at the same plate thickness (0.5 mm, 0.8 mm, and 1.0 mm). Type) bearing inner diameter when assembled in the rolling space between outer ring and inner diameter bearing ring, and ratio of bearing outer diameter to bearing inner diameter (bearing outer diameter / bearing inner diameter) ) And dynamic torque were measured for the bearing and the comparative bearing, and the measured values were compared. For comparison, the configuration of the present bearing and the comparative bearing are set such that the rolling element diameter, the number of rolling elements, the cage plate thickness, and the race ring plate thickness are set to 1.5 mm, 22 pieces, 0.3 mm, and 0.5 mm, respectively. 1. Similarly, a configuration in which the values are set to 2.0 mm, 30 pieces, 0.4 mm, and 0.8 mm, respectively, and a configuration in which the configuration is set to 2, 2.5 mm, 40 pieces, 0.5 mm, and 1.0 mm. It was set to 3, and it carried out every each structure 1 to 3. In any configuration, the position of the PCD of the rolling elements (balls or rollers) is the same, and the inclination angle of the cage window portion (angle α shown in FIG. 8) in the bearing is 50 ° for configuration 1 and 2 for configuration. Was set to 40 °, and configuration 3 was set to 30 °. The comparison results under the above conditions are shown in FIG.

As apparent from FIG. 7, in any of the configurations 1 to 3, the present bearing has a bearing inner diameter of about 4 mm to 5 mm larger than the comparative bearing, and the ratio of the outer diameter of the bearing to the inner diameter of the bearing (the outer diameter of the bearing). / The value of the inner diameter of the bearing) is about 0.4 to 0.6 smaller. That is, when the diameter and the number of rolling elements (balls or rollers), the cage and the bearing ring are the above conditions, and the PCD position is made common, the present bearing is larger in the radial width (bearing outer diameter) than the comparative bearing. It is possible to reduce (shorten) the size / the value of the inner diameter of the bearing and the ratio of the outer diameter of the bearing). Therefore, according to the thrust ball bearing which is the present bearing, it is possible to reduce the size and weight of the bearing, and as a result, the air conditioner compressor, torque converter, transmission, etc. of the automobile to which the present bearing (thrust ball bearing) is mounted. It is possible to reduce the size and weight of the in-vehicle device.
Moreover, in any of the configurations 1 to 3, the present bearing has a dynamic torque suppressed to about 1/5 that of the comparative bearing. Therefore, according to the thrust ball bearing which is the present bearing, the dynamic torque can be remarkably reduced, and as a result, it is possible to improve the efficiency of the on-vehicle apparatus such as the transmission of the automobile.

  The first embodiment (FIG. 1) described above is merely an example of a thrust ball bearing according to the present invention, and the bearing configuration is not limited to this and can be changed as appropriate. For example, FIGS. 2 to 6 show the configurations of the thrust ball bearings according to the second to sixth embodiments of the present invention, respectively. Even in the illustrated configurations, the first embodiment described above is shown. The same effect can be obtained. Hereinafter, each of these embodiments will be described. However, the basic bearing configuration of each of these embodiments is the same as that of the above-described first embodiment (FIG. 1), and members that are the same as or similar to the components are denoted by the same reference numerals in the drawings. Description is omitted or simplified, and only the configuration unique to each embodiment will be described in detail.

(Second embodiment)
The structure of the thrust ball bearing which concerns on this embodiment is shown in FIG.
In the present embodiment, the cage 8 is injection-molded with a predetermined resin (such as various synthetic resins). At that time, the cage 8 reduces the diameter of the opening peripheral edge 80a on both sides in the axial direction (left and right direction in FIG. 2) of the window portion 80 more than the axial center portion 80b, and rolls the ball 6 inserted into the window portion 80. It is molded so as to have a structure that is movable and cannot be removed (so-called both-side rolling elements are provided). Specifically, the peripheral surface area from the axial center part 80b of the window part 80 to the opening peripheral edge 80a on both axial sides is concavely curved (for example, the outer peripheral surface (rolling surface) of the ball 6 to be held). What is necessary is just to shape | mold so that the curvature may be smaller than a curvature.
When the ball 6 is inserted into the window portion 80 of the cage 8, first, the outer peripheral surface (rolling surface) of the ball 6 is formed on the opening peripheral edge 80 a on one side (regardless of which side) of the cage 8. ). From this state, the ball 6 is pressed to the other side in the axial direction, and the opening peripheral edge 80a on the one side in the axial direction is expanded along the outer peripheral surface of the ball 6, while inside the window 80 (the central portion 80b in the axial direction). Push in. Then, the ball 6 is pushed in until it comes into contact with the opening peripheral edge 80a on the other side in the axial direction, and the ball 6 is inserted into the window portion 80 (so-called snapping insertion). As a result, the ball 6 inserted into the window 80 is in a state of being sandwiched by the opening peripheral edge 80a on both sides of the cage 8 in the axial direction (the state shown in FIG. 2). Thereby, while being able to stabilize the rotation attitude | position of the ball | bowl 6 in the window part 80, it can prevent effectively the said ball | bowl 6 falling off from the window part 80. FIG.
FIG. 2 shows, as an example, a configuration in which the thickness of the cage 8 is thicker than the raceway (outer diameter raceway ring 2 and inner diameter raceway ring 4), but the first embodiment described above ( Similarly to FIG. 1), it is also possible to adopt a cage configuration that is thinner than the raceway (outer diameter raceway ring 2 and inner diameter raceway ring 4).

In the first embodiment (FIG. 1) and the second embodiment (FIG. 2) described above, the two race rings (the outer diameter race ring 2 and the inner diameter race ring 4) are arranged to face each other so as to be relatively rotatable, The bearing configuration is such that the cage 8 and the ball 6 are assembled in a rolling space between these raceway surfaces (the outer diameter side raceway surface 2s and the inner diameter side raceway surface 4s). When the surface condition of the part (hereinafter referred to as the mating raceway surface) of the automotive air conditioner compressor, torque converter, transmission, etc. in contact with the ball 6 is good (for example, surface polishing is applied to make the sliding In the case of a surface state, etc., it is also possible to adopt a bearing configuration having only one bearing ring.
Such a bearing configuration with one bearing ring will be described below as a third embodiment (FIG. 3) and a fourth embodiment (FIG. 4).

(Third embodiment)
In the present embodiment, the inner diameter raceway ring 4 in the first embodiment (FIG. 1) described above is omitted, and the raceway ring is configured only by the outer diameter raceway ring 2 (a form in which a bearing is partially opened). . The configuration of the thrust ball bearing according to this embodiment is shown in FIG.
In the present embodiment, the outer diameter raceway surface 2s of the outer diameter raceway ring 2 and the counterpart side are mounted by mounting the bearing on a counterpart side member (for example, an in-vehicle device such as a compressor for an air conditioner, a torque converter, or a transmission of an automobile). A rolling space for rolling the ball 6 is formed between the raceway surface (not shown), and an assembly (assembly) of the cage 8 and the ball 6 is disposed in the rolling space. It has a configuration. In this case, the outer diameter side protruding portion 2c of the outer diameter raceway ring 2 has a portion 20c that protrudes most in the axial direction (a protruding end in the right direction in FIG. 3) in contact with the outer diameter side raceway surface 2s. The protrusion form (protrusion length, protrusion range, etc.) is set so that it does not protrude from the ball 6 in the axial direction (rightward in the figure). Accordingly, when the bearing is mounted on the counterpart member, the outer diameter side protruding portion 2c (specifically, the protruding end 20c) is caused to interfere (abut) with the counterpart member (the counterpart raceway surface). The outer peripheral surface (rolling surface) of the ball 6 can be brought into contact with both the outer diameter side raceway surface 2s and the mating raceway surface, and a rolling space for the ball 6 is formed between these raceway surfaces. Is possible. In addition, if the assembly body (assembly) of the holder | retainer 8 and the ball | bowl 6 takes another way so that the opening periphery 80a of the window part 80 may face the other party member (an other party track surface), the opening periphery 80a Is preferably disposed in the rolling space so that the bearing faces the open side of the bearing (the right side in FIG. 3).
By configuring the bearing ring only with the outer diameter bearing ring 2 as described above, it becomes possible to further reduce the size and weight of the bearing, and as a result, further reduce the size of the in-vehicle device such as an automobile transmission to which the bearing is mounted. It is also possible to reduce the weight.

(Fourth embodiment)
In the present embodiment, the outer diameter raceway ring 2 in the first embodiment (FIG. 1) described above is omitted, and the raceway ring is configured only by the inner diameter raceway ring 4 (a form in which a bearing is partially opened). . FIG. 4 shows the configuration of the thrust ball bearing according to this embodiment.
In the present embodiment, the inner raceway surface 4s of the inner raceway ring 4 and the counterpart raceway surface are mounted by mounting the bearing on a counterpart member (for example, an in-vehicle device such as an air conditioner compressor, a torque converter, or a transmission of an automobile). A rolling space for rolling the ball 6 (not shown) is formed, and the assembly (assembly) of the cage 8 and the ball 6 is disposed in the rolling space; It has become. In this case, the inner diameter side protruding part 4c of the inner diameter raceway ring 4 has a portion 40c that protrudes most in the axial direction (a protruding end in the left direction in FIG. 4) from the ball 6 in contact with the inner diameter side raceway surface 4s. The protrusion form (protrusion length, protrusion range, etc.) is set so as not to protrude in the axial direction (leftward in the figure). Thus, when the bearing is mounted on the mating member, the inner diameter side protruding portion 4c (specifically, the projecting end 40c) does not interfere (contact) with the mating member (the mating raceway surface). The outer peripheral surface (rolling surface) of the ball 6 can be brought into contact with both the inner raceway surface 4s and the other raceway surface, and a rolling space for the ball 6 can be formed between these raceway surfaces. It becomes. In addition, if the assembly body (assembly) of the holder | retainer 8 and the ball | bowl 6 takes another way so that the opening periphery 80a of the window part 80 may face the other party member (an other party track surface), the opening periphery 80a Is preferably arranged in the rolling space so that the bearing faces the open side of the bearing (left side in FIG. 4).
In this way, by configuring the bearing ring only with the inner diameter bearing ring 4, it becomes possible to further reduce the size and weight of the bearing, and as a result, it is possible to further reduce the size and weight of the in-vehicle device to which the bearing is mounted. This is possible as in the third embodiment described above.

In the third embodiment (FIG. 3) and the fourth embodiment (FIG. 4), a bearing configuration in which the inner diameter raceway ring 4 or the outer diameter raceway ring 2 in the first embodiment (FIG. 1) described above is omitted. However, it is possible to assume a bearing configuration in which the inner diameter raceway ring 4 or the outer diameter raceway ring 2 in the second embodiment (FIG. 2) is omitted.
In the first to fourth embodiments (FIGS. 1 to 4) described above, the balls 6 are arranged at predetermined intervals (as an example, at equal intervals) along the circumferential direction with respect to a predetermined rolling space. However, when the conditions for narrowing the inner and outer diameters of the bearing are not so strict, for example, the balls 6 are arranged in a double row in the predetermined space. Alternatively, a scattered bearing configuration may be used.
A bearing configuration having a ball arrangement other than a single row forming a single PCD will be described below as a fifth embodiment (FIG. 5) and a sixth embodiment (FIG. 6).

(Fifth embodiment)
FIG. 5 shows the configuration of the thrust ball bearing according to this embodiment.
In this embodiment, in the first embodiment (FIG. 1) and the second embodiment (FIG. 2), the same radiation is applied to the rolling space between the outer diameter side raceway surface 2s and the inner diameter side raceway surface 4s. Bearing configuration in which balls 6 arranged two by two (on the same phase with respect to the circumferential direction) are arranged along the circumferential direction at a predetermined interval (for example, an equal interval) (that is, a double row ball arrangement with different PCDs) (Two rows of balls that make up two PCDs)). FIG. 5A shows a bearing configuration in which the thrust ball bearing according to the first embodiment (FIG. 1) has a two-row ball arrangement that forms two PCDs, and these balls 6 are held on one side by a cage 8. In FIG. 2 (b), the thrust ball bearing according to the second embodiment (FIG. 2) is arranged in a two-row ball configuration that forms two PCDs, and these balls 6 are held on both sides by a cage 8. This shows the bearing configuration.
In the configuration shown in FIG. 5 (a), the opening peripheral edge 80a on one axial side (left side in the figure) has a radial width slightly smaller than twice the diameter (ball diameter) of the ball 6 and the ball 6 A plurality of rectangular window portions 80 having a circumferential width slightly smaller than the diameter of the cage are punched in the retainer flat plate portion 8a by pressing or the like (FIG. 5C). On the other hand, in the configuration shown in FIG. 5B, the opening peripheral edges 80a on both sides in the axial direction (left and right sides in the figure) are both slightly smaller than twice the diameter (ball diameter) of the ball 6. A plurality of rectangular windows 80 having a radial width and a circumferential width slightly smaller than the diameter of the ball 6 are formed on the retainer flat plate portion 8a by injection molding or the like (FIG. 5 (c). )).

(Sixth embodiment)
FIG. 6 shows the configuration of the thrust ball bearing according to this embodiment.
In the second embodiment described above (FIG. 2), the present embodiment has a predetermined interval (as an example, etc.) along the circumferential direction with respect to the rolling space between the outer diameter side raceway surface 2s and the inner diameter side raceway surface 4s. A plurality of balls 6 arranged at intervals are arranged at different PCD positions and arranged so as not to be arranged in the same radial form with a phase shift with respect to the circumferential direction. That is, it has a bearing configuration in which scattered balls are arranged in different PCDs, and these balls 6 are held on both sides by a cage 8 (FIG. 6A).
In this case, the cage 8 has the opening periphery 80a on both sides in the axial direction (left and right direction in FIG. 6 (a)) having a diameter smaller than that of the central portion 80b in the axial direction, and the ball 6 inserted into the window portion 80 is rolled. The window portion 80 having a structure that can be moved and cannot be dropped (so-called both-side rolling elements) may be formed according to the ball arrangement (FIG. 6B).
In this embodiment, as shown in FIG. 6, the thrust ball bearing according to the second embodiment (FIG. 2) described above is arranged with scattered balls that form different PCDs, and these balls 6 are held on both sides by a cage 8. It is assumed that the thrust ball bearing according to the first embodiment (FIG. 1) has a scattered ball arrangement with different PCDs, and these balls 6 may be held on one side by the cage 8. It can be assumed.
Further, the thrust ball bearings according to the fifth embodiment (FIG. 5) and the sixth embodiment (FIG. 6) are arranged in the inner diameter raceways as in the third embodiment (FIG. 3) and the fourth embodiment (FIG. 4). It is also possible to assume a bearing configuration in which the ring 4 or the outer diameter raceway ring 2 is omitted (a configuration in which a part of the bearing is opened).

As described above, according to the thrust ball bearing according to the first to sixth embodiments (FIGS. 1 to 6), the radial width of the bearing (outside the bearing) is compared with the case where the same diameter and the same number of rollers are used. The inner diameter dimension ratio) can be shortened, and the bearing can be reduced in size and weight. Further, the ball 6 can be held by the cage 8 in a non-contact state with the raceway (the outer diameter raceway 2 or the inner diameter raceway 4), that is, the cage 8 can be provided with rolling elements on one side or both sides. The torque of the bearing can be reduced.
In addition, due to the structure of the thrust roller bearing, slippage occurs between the roller and the raceway (outer diameter raceway or inner raceway) during rotation, which increases the torque or induces wear on the contact area between the two. However, when the rolling element is a ball, such slip hardly occurs, so that the thrust ball bearing can easily reduce torque and prevent wear compared to the thrust roller bearing. Further, when the rolling element diameter (roller diameter) is 2.5 mm or more, depending on the shape of the cage, it is possible to have a roller in the thrust roller bearing, but the rolling element diameter (roller diameter). Is smaller than 2.5 mm, it is not easy to roll the cage. Therefore, each embodiment of the present invention in which the rolling element diameter (ball diameter) is smaller than 2.5 mm is superior to the thrust roller bearing using the same diameter roller in terms of low torque and wear resistance. have.

2 Outer diameter raceway 2a Outer diameter side flat surface portion 2b Outer diameter side cylindrical portion 2c Outer diameter side protruding portion 2s Outer diameter side raceway surface 4 Inner diameter raceway surface 4a Inner diameter side flat surface portion 4b Inner diameter side cylindrical portion 4c Inner diameter side protruding portion 4s Inner diameter side Side raceway surface 6 Ball 8 Cage 8a Cage flat plate portion 8b Cage flat plate outer peripheral portion 8c Cage flat plate inner peripheral portion 80 Cage window portion

Claims (2)

Comprising at least one raceway having a raceway surface, a plurality of balls arranged along the circumferential direction with respect to the raceway surface, and a cage for holding the balls so as to roll freely,
The raceway includes an annular race plate portion having a raceway surface, an outer diameter side cylindrical portion extending from the outer periphery portion of the track plate portion to one side in the axial direction, or the inner periphery of the plate portion. One of the inner diameter side cylindrical portion extending from the portion to the other side in the axial direction,
The retainer has an outer diameter smaller than an inner diameter of the outer diameter side cylindrical portion, or an inner diameter larger than an outer diameter of the inner diameter side cylindrical portion, or the outer diameter is the outer diameter side cylindrical portion. An annular retainer flat plate portion that is smaller than the inner diameter size and larger than the outer diameter size of the inner diameter side cylindrical portion, and along the circumferential direction with respect to the retainer flat plate portion. A plurality of windows that are perforated to hold the balls;
The outer diameter side cylindrical portion is provided with an outer diameter side protruding portion that protrudes in the diameter reducing direction and that can be engaged with the outer peripheral edge portion of the retainer flat plate portion, and The inner diameter side cylindrical portion is provided with an inner diameter side protruding portion that protrudes in the diameter-expanding peripheral end portion and can be engaged with the inner peripheral edge portion of the retainer flat plate portion,
A thrust ball bearing characterized in that the bearing ring, the cage and the ball are rotatable relative to each other and integrated in a non-separable manner.   The window portion of the cage is reduced in diameter with respect to the central portion in the axial direction so that the opening peripheral edge on one side or both sides in the axial direction is smaller than the diameter of the ball, and the ball can roll and drop off. The thrust ball bearing according to claim 1, wherein the thrust ball bearing is held impossible.

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