JP2014029176A - Revolving shaft device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a revolving shaft device in which assemblability of balls and a cage with respect to an outer ring can be improved without impairing airtightness of an oil seal.SOLUTION: The revolving shaft device is constituted to allow a lubricant to flow between an outer ring 23 and an inner ring 22 from a small-diameter outer periphery 22a to a large-diameter outer periphery 22f of the inner ring 22. An annular portion 27a of a cage 27 has an oil seal-side inner periphery 27e extending in the axial direction, and an oil seal-side end face 27f extending in the outer diameter direction with respect to an end portion at the oil seal 40 side, of the oil seal-side inner periphery 27e. An intermediate-diameter outer periphery 22d is formed on an outer periphery of the inner ring 22 with a radial clearance gap to the oil seal-side inner periphery 27e between a raceway surface 22c and the large-diameter outer periphery 22f. A stepped face 22e is formed with an axial clearance gap to the oil seal-side end face 27f. A first oil passage allowing the lubricant to axially flow, is formed between the oil seal-side inner periphery 27e and the intermediate-diameter outer periphery 22d, and a second oil passage allowing the lubricant to flow in the outer diameter direction, is formed between the oil seal-side end face 27f and the stepped face 22e.

Description

  The present invention relates to a rotating shaft device that rotatably supports a rotating shaft via an angular ball bearing.

  A differential device for an automobile transmits rotation of a pinion shaft to an axle through a ring gear, a differential gear case, and a planetary gear. As shown in FIG. 3 (Patent Document 1), the pinion shaft 100 is rotatably supported by a casing 110 via an angular ball bearing 120, and the pinion shaft 100 (rotating shaft), the angular bearing 120, and a part of the casing 110. The rotary shaft device is configured from the above.

  The angular bearing 120 includes an outer ring 121 fitted in the mounting hole 111 of the casing 110, a first inner ring 122, a second inner ring 123 arranged in two rows in the axial direction on the inner peripheral side of the outer ring 121, and an outer ring. The first ball 124 disposed between the 121 and the first inner ring 122, the second ball 125 disposed between the outer ring 121 and the second inner ring 123, and the first ball 124 are rotatably held. It consists of a first holder 126 and a second holder 127 that holds the second ball 125 rotatably.

  An oil seal 130 is fitted and fixed to the inner periphery of one end of the outer ring 121, and the two lip portions 131 and 132 provided on the inner periphery side of the oil seal 130 are slidably contacted with the second inner ring 123. ing. The oil seal 130 prevents the lubricating oil in the casing 110 from leaking outside.

  Lubricating oil in the casing 110 is supplied to the angular bearing 120. That is, the lubricating oil pumped up by the ring gear is supplied between the two rows of balls 124 and 125 via the lubricating oil groove 112 of the casing 110 and the through hole 121a of the outer ring 121, and is pumped by the angular bearing. The inner rings 122 and 123 are fed from the small diameter side to the large diameter side.

JP 2006-9930 A

  The second retainer 127 includes an annular ring body 127a and a claw 127b extending in the axial direction with respect to the ring body 127a. The ball 125 is rotatable in a pocket formed by the pair of claws 127b and the ring body 127a. Is held in. Since the annular body 127a is located on the opposite side of the oil seal 130 with the ball 125 interposed therebetween, the ball 125 is likely to be detached from the pocket when the ball 125 is fitted in the outer ring 121 with the ball 125 held in the pocket. was there.

  When the annular body 127a is positioned on the oil seal 130 side with the ball 125 interposed therebetween, the ball 125 is not easily detached from the pocket when the ball 125 is fitted into the outer ring 121 with the ball 125 held in the pocket. On the contrary, the oil passage between the inner periphery of the annular body 127a and the large-diameter outer periphery 123c of the inner ring 123 facilitates the supply of lubricating oil to the inner periphery of the lip portions 131 and 132, and the lip portions 131 and 132 are connected to the pinion shaft 100. Therefore, the airtightness of the oil seal 130 is impaired. The present invention has been made to solve the above-described problems, and an object of the present invention is to improve the assembling property of the ball and the cage with respect to the outer ring without impairing the airtightness of the oil seal.

  The invention according to claim 1 includes a casing, an angular ball bearing provided in the casing, and a rotating shaft that is rotatably supported via the angular ball bearing, and the angular ball bearing includes the casing. An outer ring attached to the rotating shaft, an inner ring attached to the rotating shaft, a ball disposed between the outer ring and the inner ring, a cage for rotatably holding the ball, and an oil fitted to the inner periphery of the outer ring A small-diameter small-diameter outer periphery, a raceway surface on which the ball rolls, and a large-diameter large-diameter outer periphery in contact with the oil seal are formed in this order on the outer periphery of the inner ring. An annular portion and a pillar portion extending in the axial direction from the annular portion, and a pocket is formed by the annular portion and the pair of pillar portions, and the space between the outer ring and the inner ring is lubricated from the small diameter outer periphery to the large diameter outer periphery. Oil flows In the above rotary shaft device, the annular portion has an oil seal side inner periphery extending in the axial direction and an oil seal side end surface extending in the outer diameter direction from the oil seal side end of the oil seal side inner periphery. An outer periphery of the inner ring is formed between the raceway surface and the outer periphery of the large diameter with a gap in the radial direction with respect to the first inner periphery, and an axial direction with respect to the end surface of the oil seal. A step surface is formed with a gap therebetween, a first oil passage is formed between the inner periphery of the oil seal and the outer periphery of the medium diameter, and a lubricating oil flows in the axial direction, between the end surface of the oil seal and the step surface. The second oil passage in which the lubricating oil flows in the outer diameter direction is formed.

  According to the present invention, it is possible to improve the assembling property of the ball and the cage with respect to the outer ring without impairing the airtightness of the oil seal.

The longitudinal cross-sectional view of the differential apparatus in embodiment of this invention The longitudinal cross-sectional view of the rotating shaft apparatus of the differential apparatus in embodiment of this invention Longitudinal sectional view of a conventional rotary shaft device

  An embodiment in which the rotating shaft device of the present invention is used in a differential device for an automobile will be described with reference to FIGS. 1 and 2. FIG. 1 is a longitudinal sectional view of a differential device, and FIG. 2 is a longitudinal sectional view of a rotating shaft device of the differential device.

  In FIG. 1, a differential apparatus 10 for an automobile has a casing 11, and a ring gear 12 is rotatably supported by the casing 11. Further, a pinion shaft 30 is rotatably supported on the casing 11 via an angular ball bearing 20. The rotation axis of the ring gear 12 and the rotation axis of the pinion shaft 30 are perpendicular to each other in the vertical direction.

  A pinion gear 30 a that meshes with the ring gear 12 is formed at one end of the pinion shaft 30, and a flange joint 31 is fixed to the other end of the pinion shaft 21. A small diameter portion 30b is formed between the pinion gear 30a of the pinion shaft 30 and the flange joint 31, and the first inner ring 21 and the second inner ring 22 of the angular ball bearing 20 are fitted into the small diameter portion 30b. The casing 11 is formed with a mounting hole 11a coaxially with the pinion shaft 30, and the outer ring 23 of the angular ball bearing 20 is fitted into the mounting hole 11a. A plurality of first balls 24 are arranged between the outer ring 23 and the first inner ring 21 so as to be able to roll, and the first cage 24 is arranged at equal intervals in the circumferential direction. It is hold | maintained at 25 so that rolling is possible. A plurality of second balls 26 are arranged between the outer ring 23 and the second inner ring 22 so as to be able to roll, and the second cage 26 is arranged such that these second balls 26 are arranged at equal intervals in the circumferential direction. 27 is held so as to be able to roll.

  The pinion shaft 30, the flange joint 31, the angular ball bearing 20, and a part of the casing 11 constitute a rotating shaft device.

  As shown in FIG. 2, a first large-diameter outer periphery 21f, a first inner-ring-side raceway surface 21c, a first inclined surface 21b, and a first small-diameter outer periphery 21a are sequentially formed on the outer periphery of the first inner ring 21. . The first large-diameter outer periphery 21 f and the first small-diameter outer periphery 21 a have a surface parallel to the axis of the first inner ring 21.

  On the outer periphery of the second inner ring 22, a second small-diameter outer periphery 22a, a second inclined surface 22b, a second inner ring-side raceway surface 22c, a medium-diameter outer periphery 22d, a step surface 22e, and a second large-diameter outer periphery 22f are formed in this order. Has been. The second small-diameter outer periphery 22 a, the medium-diameter outer periphery 22 d, and the second large-diameter outer periphery 22 f have surfaces parallel to the axis of the second inner ring 22. The step surface 22 e has a surface perpendicular to the axis of the inner rings 21 and 22.

  The diameter increases in the order of the first small-diameter outer periphery 21a and the second small-diameter outer periphery 22a, the first large-diameter outer periphery 21f, the medium-diameter outer periphery 22d, and the second large-diameter outer periphery 22f. The first small-diameter outer periphery 21a and the second small-diameter outer periphery 22a have the same diameter, and the first large-diameter outer periphery 21f and the medium-diameter outer periphery 22d have the same diameter.

  A first outer ring side raceway surface 23a and a second outer ring side raceway surface 23b are formed on the inner circumference of the outer ring 23 so as to be axially separated from each other. The first outer ring side raceway surface 23a and the second outer ring are formed. The side raceway surface 23b is formed on the inner side in the axial direction than the first inner ring side raceway surface 21c and the second inner ring side raceway surface 22c. The first ball 24 rolls on the first inner ring side raceway surface 21c and the first outer ring side raceway surface 23a, and the second ball 26 has the second inner ring side raceway surface 22c and the second inner raceway raceway surface 22c. It rolls on the outer ring side raceway surface 23b.

  The first cage 25 is a crown type cage composed of a ring-shaped first annular portion 25a and a column portion 25b extending in the axial direction. On the inner circumference of the first cage 25, a third inclined surface 25d and a first inner circumference 25c are formed in this order. The first inner periphery 25 c has a surface parallel to the first inner ring 21. The column part 25b is provided at equal intervals in the circumferential direction, and a first pocket for holding the first ball 24 in a rollable manner is formed by the first annular part 25a and the column part 25b. The column portion 25b is also a claw that expands the insertion opening of the pocket by elastic deformation when the first ball 24 is inserted.

  The second cage 27 is a crown type cage composed of a ring-shaped second annular portion 27a and a column portion 27b extending in the axial direction. On the inner periphery of the second cage 27, a second inner periphery 27c, a fourth inclined surface 27d, and a third inner periphery 27e are formed in this order. The second inner periphery 27 c and the third inner periphery 27 e have a surface parallel to the second inner ring 22. An end surface 27 f on the oil seal 40 side of the second cage 27 has a surface perpendicular to the axis of the second inner ring 22. The column part 27b is provided at equal intervals in the circumferential direction, and a second pocket is formed by the second annular part 27a and the column part 27b to hold the second ball 26 in a rollable manner. The column part 27b is also a claw that expands the insertion opening of the pocket by elastic deformation when the second ball 26 is inserted.

  A gap in the radial direction of the second inner ring 22 is provided between the medium-diameter outer periphery 22d and the third inner periphery 27e to constitute a first oil passage. Between the step surface 22e and the end surface 27f, there is a gap in the axial direction of the second inner ring 22 to constitute a second oil passage. Lubricating oil flows in the axial direction of the second inner ring 22 through the first oil path, and lubricating oil flows in the outer diameter direction of the second inner ring 22 through the second oil path.

  An oil seal 40 is fitted and fixed to the inner periphery of the outer ring 23 on the flange joint 31 side. The oil seal 40 includes a metal ring 41, a rubber part 42, and a ring-shaped band. The rubber part 42 has three lip parts 42a, 42b and 42c. The first lip portion 42 a and the second lip portion 42 b are slidably contacted with the outer periphery of the second inner ring 22, and the third lip portion 42 c is fitted and fixed to the outer periphery of the flange joint 31. It is slidably contacted with the side surface. Only the first lip portion 42a is pressed radially inward by the band.

  As shown in FIGS. 1 and 2, the casing 11 is formed with an oil introduction groove 11 b that opens at the top of the mounting hole 11 a, and one end of the oil introduction groove 11 b opens into a space 11 c inside the casing 11. The space 11c has a role of allowing the ring gear 12 to rotate and storing lubricating oil. Lubricating oil enters from the bottom of the ring gear 12 to a depth that is a quarter of the diameter of the ring gear 12. The casing 11 is formed with an oil return groove 11d that opens at a lower portion of the mounting hole 11a, and one end of the oil return groove 11d opens into a space 11c inside the casing 11.

  The outer ring 23 is formed with a pass hole 23c penetrating in the radial direction at a position corresponding to the oil introduction groove 11b. An inner diameter side of the pass hole 23 c opens at a position corresponding to the space between the first inner ring 21 and the second inner ring 22 in the axial direction of the pinion shaft 30. Further, the outer ring 23 is formed with a pass hole 23d penetrating at a position corresponding to the oil return groove 11d. An inner diameter side of the pass hole 23d opens at a position corresponding to the first annular portion 25a in the axial direction of the pinion shaft 30.

  Next, the assembly operation will be described based on the above-described configuration.

  The first ball 24 is fitted in the first pocket of the first cage 25, and the second ball 26 is fitted in the second pocket of the second cage 27. From the one side in the axial direction of the outer ring 20, the first ball 24 fitted into the first retainer 25 is fitted into the outer ring 20, and the first inner ring 21 is fitted into the first ball 24. The pinion shaft 30 is fitted into 21. From the other side in the axial direction of the outer ring 20, the second ball 26 fitted into the second cage 27 is fitted into the outer ring 20, and the oil seal 40 is fitted into the outer ring 20, and the second inner ring 22 is second. And the pinion shaft 30 at the same time.

  The protector 50 is fitted and fixed to the outer periphery of the flange joint 31, and the flange joint 31 is fixed to the other end of the pinion shaft 21. The first lip portion 42 a and the second lip portion 42 b are slidably contacted with the outer periphery of the second inner ring 22, and the third lip portion 42 c is fitted and fixed to the outer periphery of the flange joint 31. It is slidably contacted with the side surface. The outer ring 20 assembled in this manner is fitted into the mounting hole 11a of the casing 11 and fixed to the casing 11 with a bolt or the like.

  When the second ball 26 fitted into the second cage 27 is fitted into the outer ring 20, the second annular portion 27a of the second cage 27 is positioned on the oil seal 40 side with respect to the column portion 27b. Therefore, the second ball 26 does not come out from the second cage 27.

  Next, the rotation transmission operation will be described based on the configuration described above.

  When the pinion shaft 30 rotates, the ring gear 12 that meshes with the pinion shaft 30 also rotates. The rotation of the ring gear 12 is further transmitted to the axle via an unillustrated differential gear case and a planetary gear.

  Next, the flow of the lubricating oil will be described based on the configuration described above.

  Lubricating oil enters the space 11c inside the casing 11 from the bottom of the ring gear 12 to a depth that is a quarter of the diameter of the ring gear. Due to the rotation of the ring gear 12, the stored lubricating oil is lifted and guided to the oil introduction groove 11b. Further, it is guided between the first inner ring 21 and the second inner ring 22 through the pass hole 23c. The rotation of the pinion shaft 30 causes the first inner ring 21 and the second inner ring 22 to rotate by the same amount in the same direction as the pinion shaft 30, while the first ball 24 and the second ball 26 revolve around the pinion shaft 30. Rotate in the same direction. Further, the first retainer 25 and the second retainer 27 rotate in the same direction as the pinion shaft 30.

  As a result, the lubricating oil flows from the small diameter side to the large diameter side in the first inner ring 21 by the pump action of the angular ball bearing 20 itself, and is guided to the space 11 c inside the casing 11. Also, due to the pumping action of the angular ball bearing 20 itself, the lubricating oil flows from the small diameter side to the large diameter side in the second inner ring 22, and further returns to the space 11c inside the casing 11 through the pass hole 23d and the oil return groove 11d. It is. When flowing from the small diameter side to the large diameter side, the lubricating oil flows mainly in the space between the second cage 27 and the second inner ring 22. That is, the outer diameter side flows along the second inner periphery 27c and the fourth inclined surface 27d, the third inner periphery 27e, and the end surface 27f of the second cage 27, and the inner diameter side is the second inner ring 22 second. It flows along the small-diameter outer periphery 22a, the second inclined surface 22b, the second inner ring side raceway surface 22c, the medium-diameter outer periphery 22d, and the step surface 22e.

  Lubricating oil flows in the axial direction of the second inner ring 22 through the first oil passage between the medium-diameter outer periphery 22d and the third inner periphery 27e, and the lubricating oil flows through the second oil passage between the step surface 22e and the end surface 27f. 2 flows in the outer diameter direction of the inner ring 22. In this way, the first oil passage and the second oil passage finally create a flow of lubricating oil in the outer diameter direction, so that the force that causes the lip portions 42a and 42b to float away from the pinion shaft 30 acts. The airtightness of the oil seal 40 is not impaired.

  The present invention is not limited to these embodiments, and can of course be implemented in various modes without departing from the gist of the present invention.

  In the above-described embodiment, the example in which the pinion shaft 30 of the differential device 10 is applied as the rotation axis is described. However, the main shaft of a horizontal machining center of a machine tool may be applied as the rotation axis.

  Furthermore, although embodiment mentioned above described the example which applied the pinion shaft 30 of the differential apparatus 10 as a rotating shaft, you may apply the pinion shaft of the transfer apparatus of a motor vehicle as a rotating shaft.

  11: casing, 20: angular contact ball bearing, 22: second inner ring (inner ring), 22a: second small diameter outer periphery (small diameter outer periphery), 22c: second inner ring side raceway surface (track surface), 22d: medium diameter outer periphery , 22f: second large diameter outer periphery (large diameter outer periphery), 22e: stepped surface, 23: outer ring, 26: second ball (rolling element), 27: second retainer (retainer), 27a: second Annular part (annular part), 27b: pillar part, 27e: third inner circumference (oil seal side inner circumference), 27f: end face (oil seal side end face), 30: pinion shaft (rotary shaft), 40: oil seal

Claims (1)

A casing, an angular ball bearing provided in the casing, and a rotating shaft rotatably supported via the angular ball bearing;
The angular ball bearing includes: an outer ring attached to the casing; an inner ring attached to the rotary shaft; a ball disposed between the outer ring and the inner ring; a cage that rotatably holds the ball; It consists of an oil seal fitted on the inner periphery,
On the outer periphery of the inner ring, a small-diameter small-diameter outer periphery, a raceway surface on which the balls roll, and a large-diameter large-diameter outer periphery on which the oil seal slides are formed in order,
The cage includes an annular annular portion and a column portion extending in the axial direction from the annular portion, and forms a pocket with the annular portion and the pair of the column portions,
In the rotary shaft device in which lubricating oil flows between the outer ring and the inner ring from the outer periphery of the small diameter to the outer periphery of the large diameter,
The annular portion has an oil seal side inner periphery extending in the axial direction, and an oil seal side end surface extending in an outer diameter direction from an end portion of the oil seal side inner periphery on the oil seal side,
On the outer periphery of the inner ring, a medium-diameter outer periphery is formed between the raceway surface and the large-diameter outer periphery with a gap in the radial direction with respect to the oil seal-side inner periphery, and in an axial direction with respect to the oil seal-side end surface. Form a stepped surface with a gap,
A first oil passage is formed between the inner circumference of the oil seal and the outer circumference of the medium diameter. The second oil flows in the outer diameter direction between the end face of the oil seal and the step surface. A rotary shaft device characterized by forming a path.

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