JP2019052718A - Thrust roller bearing - Google Patents

Abstract

To provide a thrust roller bearing which can suppress wear by reducing a contact force between a roller rolling face and roller stop parts of pockets of an inner cage and an outer cage at the rotation of the bearing.SOLUTION: A thrust roller bearing comprises: a plurality of rollers which are arranged between a fixed-side raceway surface formed at a non-rotation member and a rotation-side raceway surface formed at a rotation member; an annular inner cage having pockets for rollingly accommodating a plurality of the rollers in a peripheral direction in a plurality of points in the peripheral direction; and an annular outer cage externally fit and connected to the inner cage, and having pockets for accommodating a plurality of the rollers in the peripheral direction in a plurality of points in the peripheral direction. In each of the pockets of a plurality of relatively-opposing pairs in an axial direction, a pocket end face of the pocket which is arranged outside in the radial direction so as to oppose the rotation-side raceway surface is located inside the radial direction of the pocket which is arranged so as oppose the fixed-side raceway surface rather than the pocket end face at the outside of the radial direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thrust roller bearing used for a compressor of a car air conditioner.

  In a compressor or the like of a car air conditioner, a thrust roller bearing that holds a plurality of rollers with two cages is used in a housing as described in Patent Document 1 below. For example, as shown in FIG. 8, in the conventional thrust roller bearing 101, a plurality of rollers 102 rotate with a raceway surface 105 </ b> A of an annular fixed side race 105 abutted against a swash plate case (non-rotating member) 103, and It is arranged between the raceway surface 107A of the annular rotation-side race 107 that is in contact with a disk portion (rotating member) 106 fitted and fixed to the outer peripheral surface of the intermediate portion of the shaft.

  The plurality of rollers 102 includes a plurality of first pockets 108A formed in the circumferential direction of the annular inner cage 108, and an annular outer cage that is externally fitted to the inner cage 108 and joined by caulking or the like. 109 is accommodated in a plurality of second pockets 109A formed in the circumferential direction, and is held so as to be able to roll in the circumferential direction with the axis of each roller 102 directed in the radial direction.

JP 2008-75752 A

  However, in the thrust roller bearing 101 described in Patent Document 1, the radial length of the first pocket 108A of the inner cage 108 and the radial direction of the second pocket 109A of the outer cage 109 are shown in FIG. The length is formed to the same length. Therefore, the pocket end surface 108B on the radially outer side of the first pocket 108A and the pocket end surface 109B on the radially outer side of the second pocket 109A are arranged in contact with a circle having the same diameter. Therefore, when the thrust roller bearing 101 rotates, the roller 102 receives a centrifugal force radially outward and is pressed against the pocket end surfaces 108B and 109B. For this reason, the roller end surface 102A on the radially outer side of the roller 102 may be in contact with both the pocket end surface 108B on the radially outer side of the first pocket 108A and the pocket end surface 109B on the radially outer side of the second pocket 109A. In some cases, only one of them may be touched.

  For example, as shown in FIG. 9, when the disc part 106 and the rotation side race 107 rotate leftward (arrow 111 direction) in FIG. 9, the roller 102 rotates clockwise (arrow 112 direction). Rotate. At the same time, as shown in FIGS. 9 and 10, the roller 102 revolves in the bearing rotation direction, that is, in the left direction (the direction of the arrow 113). The roller rolling surface (the outer peripheral surface of the cylindrical roller 102) 102B of the roller 102 includes a roller stopper (side edge in the bearing rotation direction) 108C of the first pocket 108A and a roller stopper ( The inner cage 108 and the outer cage 109 rotate in contact with the bearing rotation direction (the side edge portion in the bearing rotation direction) 109C, so that the inner cage 108 and the outer cage 109 rotate in the bearing rotation direction, that is, in the left direction (direction of arrow 113 in FIGS. ) To rotate integrally.

  Here, the roller end surface 102A (see FIGS. 8 and 9) on the radially outer side of the roller 102 contacts the pocket end surface 108B (see FIG. 8) on the radially outer side of the first pocket 108A facing the rotation side race 107. In the state, the case where the rotation-side race 107 rotates in the left direction (arrow 111 direction) in FIG. 9 will be described. By sliding between the roller end surface 102A and the pocket end surface 108B on the radially outer side of the first pocket 108A, the inner cage 108 and the outer cage 109 are moved in the bearing rotation direction (left direction in FIG. 9), that is, the roller travels. A cage forcing force F1 (see FIG. 5) is generated in the direction.

  Next, as shown in FIG. 9, the roller end surface 102 </ b> A on the radially outer side of the roller 102 is in contact with the pocket end surface 109 </ b> B (see FIG. 8) on the radially outer side of the second pocket 109 </ b> A facing the fixed side race 105. The case where the rotation-side race 107 rotates in the left direction (in the direction of arrow 111) in FIG. 9 will be described. By sliding between the roller end surface 102A and the pocket end surface 109B on the radially outer side of the second pocket 109A, the inner cage 108 and the outer cage 109 are moved in a direction opposite to the bearing rotation direction (rightward in FIG. 9). That is, the cage forcing force F2 is generated in the direction opposite to the roller traveling direction.

  Therefore, when the roller end surface 102A slides on the pocket end surface 109B, as shown in FIG. 10, the roller stopper 108C of the first pocket 108A and the roller stopper 109C of the second pocket 109 are in the bearing rotation direction ( The contact force pressed against the roller rolling surface 102B moving in the direction indicated by the arrow 113 is increased by the cage forcing force F2. As a result, frictional force and loss generated between the roller stoppers 108C and 109C and the roller rolling surface 102B increase, and wear develops between the roller stoppers 108C and 109C and the roller rolling surface 102B. There is a problem that it becomes easy to do. Further, the roller end surface 102A on the radially outer side of the roller 102 may come into contact with both the pocket end surface 108B on the radially outer side of the first pocket 108A and the pocket end surface 109B on the radially outer side of the second pocket 109A. For this reason, there is a possibility that the variation in rotational torque of the thrust roller bearing 101 becomes large.

  Therefore, the present invention has been made in view of the above points, and the contact force between the roller rolling surface and the roller stoppers of the pockets of the inner cage and the outer cage during bearing rotation. It is an object of the present invention to provide a thrust roller bearing capable of reducing wear and suppressing wear and loss.

  In order to solve the above-mentioned problems, a first aspect of the present invention includes a fixed-side raceway surface provided on a non-rotating member and having a planar shape and an annular shape, and a planar member and annular shape provided on a rotating member. And a plurality of rollers disposed between the fixed-side raceway surface and a rotation-side raceway surface provided to face the fixed-side raceway surface at a predetermined interval, and the plurality of rollers can be rolled in the circumferential direction. An annular inner cage having a plurality of pockets in the circumferential direction, and a plurality of pockets in the circumferential direction that are externally fitted to the inner cage and accommodated so that the rollers can roll in the circumferential direction. Each of the plurality of pairs of pockets opposed to each other in the axial direction of the inner cage and the outer cage that are arranged coaxially, and facing the rotation-side raceway surface. Radially outside the pockets arranged to Pocket end face of the than the radial outer side of the pocket end face of the arranged said pocket so as to face the fixed-side raceway surface, is provided so as to be located radially inward, a thrust roller bearing.

  Next, according to a second aspect of the present invention, in the thrust roller bearing according to the first aspect, the inner cage is disposed to face the rotation-side raceway surface, and the outer cage is The inner cage is arranged to face the fixed-side raceway surface, and the inner cage includes the first annular part in which the pockets are formed at a plurality of locations in the circumferential direction, and the axial direction from the inner peripheral edge of the first annular part. And a first outer cylindrical portion protruding in the axial direction from an outer peripheral edge of the first annular portion, and the outer retainer has a pocket around the pocket. A second annular portion formed at a plurality of locations in the direction, a second inner peripheral cylindrical portion protruding in the axial direction from an inner peripheral edge of the second annular portion, and an outer peripheral edge of the second annular portion. A second outer peripheral cylindrical portion protruding in the axial direction, and the second inner peripheral cylindrical portion and the second outer peripheral cylindrical portion are In each of the plurality of pairs of pockets that are fitted on the radially outer side of one inner circumferential side cylindrical portion and the first outer circumferential side cylindrical portion, coupled by caulking, and opposed to each other in the axial direction, the first annular ring The pocket end surface on the radially outer side of the pocket formed in the portion is provided so as to be located on the radially inner side of the pocket end surface on the radially outer side of the pocket formed in the second annular portion. This is a thrust roller bearing.

  Next, according to a third aspect of the present invention, there is provided the thrust roller bearing according to the first aspect or the second aspect, wherein an annular fixed race in which the fixed side raceway surface is formed, and the rotation side raceway surface. A thrust roller bearing comprising: an annular drive race formed with

  Next, a fourth invention of the present invention is the thrust roller bearing according to any one of the first to third inventions, wherein the plurality of rollers are the fixed side raceway surface and the rotation side raceway surface. A plurality of rows arranged along the same radial direction between the inner cage and the outer cage, wherein the inner cage and the outer cage have the pockets arranged along the same radial direction at a plurality of locations in the circumferential direction. It is a bearing.

  According to the first invention, the radial length of the pocket arranged so as to face the fixed-side raceway surface is set larger than the radial length of the pocket arranged so as to face the rotation-side raceway surface. When the bearing is rotated, the roller end surface on the radially outer side of the roller that receives the centrifugal force radially outward and the pocket end surface on the radially outer side of the pocket arranged so as to face the rotation side raceway surface must be slid. be able to.

  As a result, when the bearing rotates, the inner cage and the outer cage can generate a cage forcing force in the bearing rotation direction, that is, in the roller traveling direction, and the roller rolling surface, the inner cage and the outer cage Wear and loss can be suppressed by reducing the contact force between the roller stoppers of each pocket. In addition, the cage forcing force generated in the inner cage and the outer cage can be made constant during bearing rotation, and the size and variation of the rotational torque of the thrust roller bearing can be reduced to improve efficiency. Can do.

  According to the second aspect of the invention, the outer retainer is disposed on the radially outer side of the first outer peripheral side cylindrical portion of the inner cage disposed so as to face the rotation side raceway surface so as to face the fixed side raceway surface. The second outer peripheral side cylindrical portion of the vessel is fitted and caulked. Thereby, the 1st outer peripheral side cylindrical part of an inner cage is arranged in the diameter direction inside to the 2nd outer peripheral side cylindrical part of an outer cage. As a result, if the pocket end surface on the radially outer side of the pocket of the inner cage is provided so as to be located on the radially inner side by a predetermined distance from the pocket end surface on the radially outer side of the pocket of the outer cage, the inner cage Since the pockets do not interfere with the bent R portion of the first outer cylindrical portion, the thrust roller bearing does not need to be expanded in the radial direction, and is the same as that of the first invention in the same bearing space as the prior art. The effect can be demonstrated.

  According to the third invention, by forming the fixed race assembled to the non-rotating member and the driving race assembled to the rotating member with the metal plate having sufficient hardness and surface accuracy, the roller, the fixed race, and the driving race The sliding frictional resistance can be suppressed, and high efficiency and long life can be easily achieved.

  According to the fourth invention, since the plurality of rollers can be arranged in a plurality of rows along the same radial direction by the inner cage and the outer cage, it is possible to increase the load of the thrust roller bearing.

It is a fragmentary sectional view of the thrust roller bearing which concerns on 1st Embodiment. It is a front view of the thrust roller bearing shown in the state which removed the fixed race and drive race of FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 1, showing a state where a roller end surface on the radially outer side of the roller and a pocket end surface on the radially outer side of the first pocket of the inner cage slide. It is a VV arrow sectional view of Drawing 1. It is a fragmentary sectional view of the thrust roller bearing which concerns on 2nd Embodiment. FIG. 7 is a partial cross-sectional view showing the inner cage and the outer cage of FIG. 6 with a roller removed. It is a fragmentary sectional view of the conventional thrust roller bearing. FIG. 9 is a cross-sectional view taken along arrow IX-IX in FIG. 8, showing a state in which the roller end surface on the radially outer side of the roller and the pocket end surface on the radially outer side of the second pocket of the outer cage slide. It is XX arrow sectional drawing of FIG.

  Hereinafter, a thrust roller bearing according to the present invention will be described in detail with reference to the drawings based on a first embodiment and a second embodiment. First, the thrust roller bearing 11 according to the first embodiment will be described with reference to FIGS. 1 to 5.

[First embodiment]
As shown in FIG. 1, in the thrust roller bearing 11 according to the first embodiment, a plurality of rollers 12 are fixed to an annular fixed race 15 assembled to a non-rotating member 13 such as a housing constituting a compressor of a car air conditioner. It is arranged between the side raceway surface 15A and the rotation side raceway surface 17A of the annular drive race 17 assembled to the rotary member 16 such as a disk part fitted and fixed to the outer peripheral surface of the intermediate part of the rotary shaft. . The plurality of rollers 12 are externally fitted to the plurality of first pockets 18 </ b> A formed in the circumferential direction of the annular inner cage 18 disposed so as to face the drive race 17 and the inner cage 18. It is accommodated in a plurality of second pockets 19A formed in the circumferential direction of an annular outer cage 19 joined by caulking or the like, and can be rolled in the circumferential direction with the axis of each roller 12 directed in the radial direction. Is held in. The annular outer cage 19 is disposed so as to face the fixed race 15.

  As shown in FIGS. 2 and 3, the annular inner cage 18 includes a ring-shaped first annular portion 181 integrally formed by pressing a metal plate, and an inner peripheral edge of the first annular portion 181. The first inner peripheral cylindrical portion 182 that protrudes in the axial direction from the first outer peripheral side cylindrical portion 182 and the first outer peripheral side cylindrical portion 183 that protrudes in the axial direction from the outer peripheral edge of the first annular portion 181. A plurality of first pockets 18A (24 in FIG. 2) are formed in the first annular portion 181 at equal intervals in the circumferential direction.

  The annular outer cage 19 includes a ring-shaped second annular portion 191 integrally formed by pressing a metal plate material, and a second inner circumference protruding in the axial direction from the inner peripheral edge of the second annular portion 191. A side cylindrical portion 192 and a second outer peripheral side cylindrical portion 193 projecting in the axial direction from the outer peripheral edge of the second annular portion 191 are formed. The second annular portion 191 is formed with a plurality of (24 in FIG. 2) second pockets 19A at equal intervals in the circumferential direction. The radial distance between the inner peripheral surfaces of the second inner peripheral side cylindrical portion 192 and the second outer peripheral side cylindrical portion 193 of the outer cage 19 is the same as that of the first inner peripheral side cylindrical portion 182 of the inner cage 18. It is formed to be slightly larger (for example, about 0.1 to 0.2 mm) than the radial distance between the outer peripheral surfaces of the first outer cylindrical portion 183.

  Therefore, first, the rollers 12 are placed in the first pockets 18 </ b> A of the inner cage 18. In this state, the outer retainer 19 is arranged coaxially with the rotation shaft 21 of the inner retainer 18, and the second inner periphery is accommodated in each second pocket 19 </ b> A of the outer retainer 19. The side cylindrical portion 192 and the second outer peripheral side cylindrical portion 193 are fitted on the radially outer sides of the first inner peripheral side cylindrical portion 182 and the first outer peripheral side cylindrical portion 183. Subsequently, the distal end portions of the second inner circumferential side cylindrical portion 192 and the second outer circumferential side cylindrical portion 193 are crimped to the first annular portion 181 side over the entire circumference, and the inner cage 18 and the outer cage 19 are moved. Combined. As a result, as shown in FIGS. 1 and 2, each roller 12 is housed and held in the first pocket 18A and the second pocket 19A so as to be able to roll in the circumferential direction.

  As shown in FIG. 3, the first inner peripheral side pocket end surface 18 </ b> E on the radially inner side of the first pocket 18 </ b> A of the inner cage 18, and the second inner circumferential side on the radially inner side of the second pocket 19 </ b> A of the outer cage 19. The pocket end surface 19E is provided at a position substantially opposite to the pocket end surface 19E. Further, as shown in FIG. 1, the radial length of the first pocket 18 </ b> A of the inner cage 18 is slightly larger than the axial length of the roller 12 (for example, about 0.05 mm to 0.1 mm). Is formed.

  Here, as shown in FIG. 3, the first outer peripheral side pocket end surface 18 </ b> B on the outer side in the radial direction of the first pocket 18 </ b> A of the inner cage 18 is the second outer circumference on the outer side in the radial direction of the second pocket 19 </ b> A of the outer cage 19. It is formed so as to be located radially inward from the side pocket end surface 19B by a predetermined distance L (for example, L = 0.05 mm to 0.2 mm, preferably L = 0.08 mm to 0.12 mm). ing. Accordingly, as shown in FIGS. 1 and 3, the radial length of each first pocket 18 </ b> A of the inner cage 18 is formed to be shorter than the radial length of each second pocket 19 </ b> A of the outer cage 19. The radial length of the first pocket 18A is different from the radial length of the second pocket 19A.

  Next, an example of a state in which the drive race 17 and the rotating member 16 of the thrust roller bearing 11 configured as described above are rotated will be described with reference to FIGS. 4 and 5. As shown in FIG. 4, when the rotating member 16 and the drive race 17 are rotated in the left direction (arrow 25 direction) in FIG. 4, the roller 12 rotates in the clockwise direction (arrow 26 direction). At the same time, as shown in FIGS. 4 and 5, the roller 12 revolves in the bearing rotation direction, that is, in the left direction (the direction of the arrow 27).

  The roller rolling surface (the outer peripheral surface of the cylindrical roller 12) 12B of the roller 12 includes a roller stopper (side edge in the bearing rotation direction) 18C of the first pocket 18A and a roller stopper of the second pocket 19A ( The bearing rotates in contact with and presses the side edge portion 19C in the bearing rotation direction. For this reason, the inner cage 18 and the outer cage 19 rotate integrally in the bearing rotation direction, that is, in the left direction (arrow 27 direction) in FIGS.

  As shown in FIGS. 1 and 3, the first outer peripheral side pocket end surface 18B of the first pocket 18A is positioned radially inward by a predetermined distance L from the second outer peripheral side pocket end surface 19B of the second pocket 19A. . Further, when the roller 12 rotates integrally with the inner cage 18 and the outer cage 19, the roller 12 receives a centrifugal force radially outward. For this reason, as shown in FIG. 4, the roller end surface 12A on the radially outer side of the roller 12 always comes into contact with and slides on the first outer peripheral side pocket end surface 18B on the radially outer side of the first pocket 18A.

  As a result, the roller member 16 and the drive member 16 are driven in a state in which the roller end surfaces 12A on the radially outer side of all the rollers 12 are in contact with the first outer pocket side surface 18B on the radially outer side of the first pocket 18A facing the drive race 17. The race 17 rotates leftward (arrow 25 direction) in FIG. In this case, by sliding between the roller end surface 12A of each roller 12 and the first outer peripheral side pocket end surface 18B on the radially outer side of each first pocket 18A, the inner cage 18 and the outer cage 19 are The cage forcing force F1 is generated in the bearing rotation direction (left direction in FIG. 4), that is, in the roller traveling direction (arrow 27 direction).

  Therefore, as shown in FIG. 5, since the cage forcing force F1 is always generated in the roller traveling direction, the roller rolling surface 12B of each roller 12 and the pockets 18A, 19A of the inner cage 18 and the outer cage 19 are provided. The contact force between each of the roller stoppers 18C and 19C can be reduced to suppress wear. Further, when the rotating member 16 and the drive race 17 are rotated, that is, when the bearing is rotated, the roller end surface 12A on the radially outer side of all the rollers 12 is the first radially outer side of the first pocket 18A facing the drive race 17. Since it slides on the outer peripheral side pocket end face 18B, the cage forcing force F1 generated in the inner cage 18 and the outer cage 19 can be made constant, and the magnitude and variation of the rotational torque of the thrust roller bearing 11 can be reduced. Thus, high efficiency can be achieved.

  Further, since the inner cage 18 is externally fitted with the outer cage 19 and is joined by caulking, the first outer cylindrical portion 183 of the inner cage 18 is connected to the second outer cylindrical portion 193 of the outer cage 19. Is disposed radially inward. As a result, the first outer peripheral side pocket end surface 18B on the outer side in the radial direction of the first pocket 18A of the inner cage 18 is more than the second outer peripheral side pocket end surface 19B on the outer side in the radial direction of the second pocket 19A of the outer cage 19. If the first pocket 18A does not interfere with the bending R portion of the first outer peripheral side cylindrical portion 183 of the inner cage 18 if provided so as to be located radially inward by the predetermined distance L, the thrust roller bearing 11 is provided. There is no need to expand in the radial direction, and it can be mounted in the same bearing space as before.

  Further, by forming the fixed race 15 assembled to the non-rotating member 13 and the driving race 17 assembled to the rotating member 16 with a metal plate having sufficient hardness and surface accuracy, the roller 12, the fixed race 15 and the driving race 17 are formed. The sliding frictional resistance can be suppressed, and high efficiency and long life can be easily achieved.

[Second Embodiment]
Next, a thrust roller bearing 31 according to a second embodiment will be described with reference to FIGS. In addition, the same code | symbol as the thrust roller bearing 11 which concerns on the said 1st Embodiment shows the same part as the thrust roller bearing 11 which concerns on the said 1st Embodiment, or an equivalent part.

  The thrust roller bearing 31 according to the second embodiment has substantially the same configuration as the thrust roller bearing 11 according to the first embodiment. However, as shown in FIG. 6, in the thrust roller bearing 31 according to the second embodiment, the plurality of rollers 12 are disposed between the fixed raceway surface 15 </ b> A of the fixed race 15 and the rotary raceway surface 17 </ b> A of the drive race 17. In addition to being arranged along the circumferential direction, two rows are arranged along the same radial direction. A plurality of first pockets 18 </ b> A are formed in the circumferential direction in the annular inner cage 32 arranged so as to face the drive race 17, and two rows are formed along the same radial direction. .

  A plurality of second pockets 19 </ b> A are formed in the circumferential direction in the annular outer cage 33 arranged so as to face the fixed race 15, and two rows are formed along the same radial direction. The plurality of rollers 12 includes a plurality of first pockets 18A of the annular inner cage 32 and a plurality of second pockets of the annular outer cage 33 that are externally fitted to the inner cage 32 and joined by caulking or the like. It is accommodated in the pocket 19A, and is held so as to be able to roll in the circumferential direction with the axis of each roller 12 oriented in the radial direction.

  As shown in FIG. 7, the annular inner cage 32 includes a ring-shaped first annular portion 321 formed integrally by pressing a metal plate material, and an axial direction from the inner peripheral edge of the first annular portion 321. Are formed from a first inner cylindrical portion 182 that protrudes in the axial direction and a first outer cylindrical portion 183 that protrudes in the axial direction from the outer peripheral edge of the first annular portion 321. A plurality of first pockets 18A are formed in the first annular portion 321 at equal intervals in the circumferential direction (for example, 24), and two rows are formed along the same radial direction. Yes.

  The annular outer cage 33 includes a ring-shaped second annular portion 331 integrally formed by pressing a metal plate material, and a second inner circumference protruding in the axial direction from the inner peripheral edge of the second annular portion 331. A side cylindrical portion 192 and a second outer peripheral side cylindrical portion 193 projecting in the axial direction from the outer peripheral edge of the second annular portion 331 are formed. In the second annular portion 331, a plurality of second pockets 19A are formed at equal intervals in the circumferential direction (for example, 24), and two rows are formed along the same radial direction. Yes. Further, the radial distance between the inner peripheral surfaces of the second inner peripheral side cylindrical portion 192 and the second outer peripheral side cylindrical portion 193 of the outer cage 33 is the same as the first inner peripheral side cylindrical portion 182 of the inner cage 32. It is formed to be slightly larger (for example, about 0.1 to 0.2 mm) than the radial distance between the outer peripheral surfaces of the first outer cylindrical portion 183.

  Therefore, first, the rollers 12 are placed in the first pockets 18 </ b> A of the inner cage 32. In this state, the second inner peripheral side cylindrical portion 192 and the second outer peripheral side cylindrical portion 193 are configured so that the rollers 12 are accommodated in the respective second pockets 19A of the outer cage 33. 182 and the first outer peripheral side cylindrical portion 183 are fitted on the outside in the radial direction. Subsequently, the distal end portions of the second inner peripheral side cylindrical portion 192 and the second outer peripheral side cylindrical portion 193 are caulked to the first annular portion 321 side over the entire circumference, and the inner retainer 32 and the outer retainer 33 are moved. Combined. As a result, as shown in FIG. 6, each roller 12 is housed and held in the first pocket 18A and the second pocket 19A so as to be able to roll in the circumferential direction.

  As shown in FIG. 7, the first inner peripheral side pocket end face 18 </ b> E inside the first pocket 18 </ b> A formed in two rows along the same radial direction of the inner cage 32 and the same of the outer cage 33. The second pockets 19A formed in two rows along the radial direction are provided at substantially opposite positions in the axial direction to the second inner peripheral side pocket end surface 19E on the radial inner side. Further, as shown in FIG. 6, the radial length of each first pocket 18 </ b> A of the inner cage 32 is slightly larger (for example, about 0.05 mm to 0.1 mm) than the axial length of the roller 12. It is formed as follows.

  Further, similarly to the thrust roller bearing 11 according to the first embodiment, the first outer peripheral side pocket end surface on the radially outer side of the first pockets 18A formed in two rows along the same radial direction of the inner cage 32. 18B is a predetermined distance L (for example, L = 0.0) from the second outer peripheral side pocket end surface 19B on the radially outer side of each second pocket 19A formed in two rows along the same radial direction of the outer cage 33. 05 mm to 0.2 mm, and preferably L = 0.08 mm to 0.12 mm). Accordingly, as shown in FIGS. 6 and 7, the radial length of each first pocket 18 </ b> A of the inner cage 32 is formed to be shorter than the radial length of each second pocket 19 </ b> A of the outer cage 33. The radial length of each first pocket 18A is different from the radial length of each second pocket 19A.

  Accordingly, in the thrust roller bearing 31 according to the second embodiment, when each roller 12 rotates integrally with the inner cage 32 and the outer cage 33, similarly to the thrust roller bearing 11 according to the first embodiment. Since the rollers 12 receive a centrifugal force radially outward, the roller end surface 12A on the radially outer side of each roller 12 always comes into contact with the first outer peripheral side pocket end surface 18B on the radially outer side of the first pocket 18A. Move. As a result, the cage compulsory generated in the inner cage 32 and the outer cage 33 by sliding between the roller end surface 12A of each roller 12 and the first outer peripheral side pocket end surface 18B on the radially outer side of each first pocket 18A. The force F1 is always generated in the roller traveling direction.

  As a result, the contact force between the roller rolling surface 12B of each roller 12 and the roller stoppers 18C and 19C of the pockets 18A and 19A of the inner cage 32 and the outer cage 33 is reduced, and wear is reduced. Can be suppressed. Further, when the rotating member 16 and the drive race 17 are rotated, that is, when the bearing is rotated, the roller end surface 12A on the radially outer side of all the rollers 12 is the first radially outer side of the first pocket 18A facing the drive race 17. Since it slides on the outer peripheral side pocket end face 18B, the cage forcing force F1 generated in the inner cage 32 and the outer cage 33 can be made constant, and the magnitude and variation of the rotational torque of the thrust roller bearing 31 can be reduced. Thus, high efficiency can be achieved.

  Further, since the inner cage 32 is externally fitted with the outer cage 33 and is coupled by caulking, the first outer cylindrical portion 183 of the inner cage 32 is the second outer cylindrical portion 193 of the outer cage 33. Is disposed radially inward. As a result, the first outer peripheral side pocket end surface 18B on the outer side in the radial direction of the first pocket 18A positioned on the outer side in the radial direction of the inner cage 32 is changed in the radial direction of the second pocket 19A on the outer side in the radial direction of the outer cage 33. If it is provided so as to be positioned radially inward by a predetermined distance L from the outer second outer peripheral side pocket end surface 19B, the first pocket 18A is formed in the bending R portion of the first outer peripheral side cylindrical portion 183 of the inner cage 32. Since there is no interference, the thrust roller bearing 31 does not need to be expanded in the radial direction, and can be mounted in the same bearing space as in the prior art.

  Further, since the plurality of rollers 12 can be arranged in two rows along the same radial direction by the inner cage 32 and the outer cage 33, the thrust roller bearing 31 can be increased in load. The plurality of rollers 12 may be arranged in three or more rows along the same radial direction. Thereby, the further high load of the thrust roller bearing 31 can be achieved easily.

  The present invention is not limited to the first and second embodiments, and various improvements, modifications, additions and deletions can be made without departing from the scope of the present invention. is there. In the following description, the same reference numerals as those of the thrust roller bearing 11 according to the first embodiment in FIGS. 1 to 5 are the same as or equivalent to those of the thrust roller bearing 11 according to the first embodiment. The part is shown.

  (A) For example, a plurality of (for example, 24) first pockets 18A may be formed in the second annular portion 191 of the annular outer cage 19 at equal intervals in the circumferential direction. . A plurality of (for example, 24) second pockets 19A may be formed in the first annular portion 181 of the annular inner cage 18 at equal intervals in the circumferential direction. Further, the first outer peripheral side pocket end surface 18B on the outer side in the radial direction of the first pocket 18A of the outer cage 19 is more predetermined than the second outer peripheral side pocket end surface 19B on the outer side in the radial direction of the second pocket 19A of the inner cage 18. The distance L (for example, L = 0.05 mm to 0.2 mm, preferably L = 0.08 mm to 0.12 mm) may be formed so as to be located on the radially inner side.

  Then, in a state where the rollers 12 are accommodated in the first pocket 18A and the second pocket 19A so as to be able to roll in the circumferential direction, the inner cage 18 is disposed so as to face the fixed race 15, and the outer cage 19 is connected to the driving race. 17 may be arranged so as to face 17. Thereby, when the rotating member 16 and the drive race 17 rotate, the sliding between the roller end surface 12A of each roller 12 and the first outer peripheral side pocket end surface 18B on the radially outer side of each first pocket 18A, A cage forcing force F <b> 1 is generated in the inner cage 18 and the outer cage 19 in the bearing rotation direction, that is, in the roller traveling direction.

  Therefore, since the cage forcing force F1 is always generated in the roller traveling direction, the roller rolling surface 12B of each roller 12, the roller stopper 19C of each second pocket 19A of the inner cage 18, and each of the outer cage 19 are provided. The contact force between the first pocket 18A and the roller stopper 18C can be reduced to suppress wear. Further, when the rotating member 16 and the drive race 17 are rotated, that is, when the bearings are rotated, the roller end surfaces 12A on the radially outer side of all the rollers 12 are in the first pockets 18A of the outer cage 19 facing the drive race 17. Since it slides on the radially outer first outer peripheral side pocket end face 18B, the cage forcing force F1 generated in the inner cage 18 and the outer cage 19 can be made constant, and the rotational torque of the thrust roller bearing can be increased. The efficiency can be improved by reducing the length and variation.

  (B) In the description of the thrust roller bearings 11 and 31 according to the first and second embodiments, the fixed race 15 having the fixed raceway surface 15A and the drive race 17 having the rotation side raceway surface 17A. An example of a configuration including the above has been described. However, the fixed race 15 and the driving race 17 are omitted, the non-rotating member 13 is provided with a flat and annular fixed raceway surface 15A, and the rotary member 16 is planar and annular and the fixed raceway surface. The rotation-side raceway surface 17A may be provided so as to face 15A with a predetermined interval, and the thrust roller bearing may be configured by only the plurality of rollers 12, the inner cage 18, and the outer cage 19.

11, 31, 101 Thrust roller bearing 12 Roller 13 Non-rotating member 15 Fixed race 15A Fixed raceway surface 16 Rotating member 17 Drive race 17A Rotating raceway surface 18, 108 Inner cage 18A, 108A First pocket 18B First outer peripheral side Pocket end surface 19, 109 Outer cage 19A, 109A Second pocket 19B Second outer peripheral side pocket end surface 21 Rotating shaft 105 Fixed side race 107 Rotating side race 105A, 107A Track surface 108B, 109B Pocket end surface 181, 321 First annular portion 182 First inner peripheral side cylindrical part 183 First outer peripheral side cylindrical part 191, 331 Second annular part 192 Second inner peripheral side cylindrical part 193 Second outer peripheral side cylindrical part

Claims (4)

A fixed-side raceway surface provided on the non-rotating member that is planar and annular, and a flat-side and annular surface provided on the rotation member and facing the fixed-side raceway surface with a predetermined interval. A plurality of rollers arranged between the rotation-side raceway surface provided as described above,
An annular inner cage having pockets for accommodating a plurality of rollers in a circumferential direction so as to be able to roll in a circumferential direction;
An annular outer retainer that is externally fitted to the inner retainer and is coupled, and has pockets that accommodate the plurality of rollers in a circumferentially rollable manner at a plurality of locations in the circumferential direction;
With
In each of the plurality of pairs of the pockets opposed to each other in the axial direction of the inner cage and the outer cage arranged coaxially, the pockets arranged on the radially outer side of the pockets arranged to face the rotation side raceway surface. The pocket end surface is provided so as to be located on the radially inner side of the pocket end surface on the radially outer side of the pocket disposed so as to face the fixed-side raceway surface.
Thrust roller bearing. The thrust roller bearing according to claim 1,
The inner cage is arranged to face the rotation side raceway surface,
The outer cage is arranged to face the fixed-side raceway surface,
The inner cage is
A first annular portion in which the pocket is formed at a plurality of locations in the circumferential direction;
A first inner peripheral cylindrical portion protruding in the axial direction from an inner peripheral edge of the first annular portion;
A first outer cylindrical portion protruding in the axial direction from an outer peripheral edge of the first annular portion;
Have
The outer cage is
A second annular portion in which the pocket is formed at a plurality of locations in the circumferential direction;
A second inner peripheral cylindrical portion protruding in the axial direction from an inner peripheral edge of the second annular portion;
A second outer peripheral cylindrical portion protruding in the axial direction from an outer peripheral edge of the second annular portion;
Have
The second inner peripheral side cylindrical portion and the second outer peripheral side cylindrical portion are fitted on the radially outer side of the first inner peripheral side cylindrical portion and the first outer peripheral side cylindrical portion, and are joined by caulking,
In each of the plurality of pairs of the pockets opposed to each other in the axial direction, the pocket end surface on the radially outer side of the pocket formed in the first annular portion is the pocket end surface of the pocket formed in the second annular portion. It is provided so as to be located on the radially inner side than the pocket end surface on the radially outer side,
Thrust roller bearing. In the thrust roller bearing according to claim 1 or 2,
An annular fixed race formed with the fixed-side raceway surface;
An annular drive race in which the rotation-side raceway surface is formed;
With
Thrust roller bearing. In the thrust roller bearing according to any one of claims 1 to 3,
The plurality of rollers are arranged in a plurality of rows along the same radial direction between the fixed-side raceway surface and the rotation-side raceway surface,
The inner cage and the outer cage have the pockets arranged in a plurality of rows along the same radial direction at a plurality of locations in the circumferential direction.
Thrust roller bearing.

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