JP2010169139A - Roller bearing of planetary gearing mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roller bearing of planetary gearing mechanism which can reduce a sliding resistance of retainer with respect to a central hole of planetary gear. <P>SOLUTION: The roller bearing of planetary gearing mechanism is equipped with a plurality of rollers 11 incorporated between a central hole 5 of planetary gear 4 of planetary gearing mechanism and a central shaft 6, and retainer 20. The retainer 20 is equipped with both circular ring sections 21 axially arranged at a predetermined space, and a plurality of pillar sections 30 which connect these both circular ring sections 21, and process in partitioning formation a plurality of pockets 25 housing the plurality of rollers 11, respectively. In the retainer 20, a projection 45 is integrally arranged which projects until a periphery having an outer diameter dimension greater than an outer diameter dimension of the retainer 20 and can contact with an inner circumferential surface of the central hole 5 of the planetary gear 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a roller bearing for a planetary gear mechanism.

In the planetary gear mechanism, the planetary gear (planetary gear) is rotatably supported on the outer periphery of the central shaft assembled to the carrier via a roller bearing. The planetary gear revolves around the sun gear while rotating around the central axis while the sun gear (sun gear) and the ring gear mesh with each other.
The roller bearing (including the needle roller bearing) includes a plurality of rollers incorporated between the center hole and the center shaft of the planetary gear, and a cage that holds the plurality of rollers in a rollable manner. Yes.
In addition, as a roller bearing of a planetary gear mechanism, it is disclosed by patent document 1, for example.

JP 2004-353808 A

By the way, in the roller bearing of the conventional planetary gear mechanism described above, the outer diameter dimension of the cage is set smaller than the inner diameter dimension of the center hole of the planetary gear, and the inner diameter dimension of the cage is the outer diameter dimension of the center shaft. Is set larger than. The gap dimension between the inner circumferential surface of the cage and the outer circumferential surface of the central shaft is larger than the gap dimension between the outer circumferential surface of the cage and the inner circumferential surface of the center hole of the planetary gear.
For this reason, when the cage receives the centrifugal force when the planetary gear rotates around the central axis and revolves around the sun gear, the cage moves in the direction in which the centrifugal force acts, and the outer peripheral surface of the cage One side (the front side of the outer peripheral surface in the moving direction of the cage) contacts the inner peripheral surface of the center hole of the planetary gear. As a result, the sliding resistance of the cage increases, which may cause torque loss.
In addition, when the roller bearing cage is subjected to centrifugal force and deformed into an oval shape with its own mass, the outer circumferential surface of the cage is in surface contact with the inner circumferential surface of the center hole of the planetary gear. The sliding resistance of the vessel is further increased.

  In view of the above problems, an object of the present invention is to provide a planetary gear mechanism roller bearing capable of reducing the sliding resistance of the cage with respect to the center hole of the planetary gear.

In order to solve the above problems, a roller bearing of a planetary gear mechanism according to claim 1 of the present invention includes a plurality of rollers and a cage incorporated between a center hole and a center shaft of a planetary gear of the planetary gear mechanism. A roller bearing provided,
The retainer includes a plurality of pillars that define both a plurality of annular portions arranged at predetermined intervals in the axial direction, and a plurality of pockets that individually connect the plurality of rollers and that respectively accommodate the plurality of rollers. With
The retainer is integrally provided with a protrusion that protrudes to a circumference having an outer diameter larger than the outer diameter of the retainer and that can contact the inner peripheral surface of the center hole of the planetary gear. It is characterized by being.

According to the above configuration, when the cage receives a centrifugal force when the planetary gear rotates around the central axis and revolves around the sun gear, the cage moves in a direction in which the centrifugal force acts.
At this time, it contacts the inner peripheral surface of the center hole of the planetary gear with a small contact area of the protruding end of the protrusion protruding from the outer peripheral surface of the cage.
This prevents the outer peripheral surface of the cage from coming into contact with the inner peripheral surface of the center hole of the planetary gear, so that the sliding resistance of the cage can be kept small. As a result, the sliding resistance of the cage is reduced. Torque loss due to can be suppressed.

The roller bearing of the planetary gear mechanism according to claim 2 is a roller bearing of the planetary gear mechanism according to claim 1,
The protrusions are each formed in a cut-and-raised shape in a part of the periphery of the plurality of pockets, and are scattered in the circumferential direction.

According to the said structure, when forming a some pocket in the predetermined position of a flat steel plate by stamping of a press, it can cut and raise a part around a some pocket and can form a protrusion easily.
In addition, since the lubricating oil supplied from the central shaft side toward the center hole of the planetary gear flows toward the inner peripheral surface of the center hole of the planetary gear through the gap of the raised portion of the protrusion of the cage, The flow becomes smooth.

The roller bearing of the planetary gear mechanism according to claim 3 is the roller bearing of the planetary gear mechanism according to claim 1,
The protrusions are characterized by being formed in a cut-and-raised shape at both ends in the axial direction around the plurality of pockets and scattered in the circumferential direction.

According to the said structure, when forming a some pocket in the predetermined position of a flat steel plate by stamping of a press, the axial direction both ends of a some pocket can be cut and raised and a processus | protrusion can be formed easily.
In addition, the lubricating oil supplied from the central shaft side toward the center hole of the planetary gear passes through the clearance between the raised portions of the protrusions of the cage, and reaches the inner peripheral surface of the center hole of the planetary gear and both end edges in the axial direction of the cage. The flow of the lubricating oil is further smoothed.

It is explanatory drawing which simplifies and shows the planetary gear mechanism which concerns on Example 1 of this invention. It is a longitudinal section showing the state where a roller bearing was similarly assembled between a planetary gear and a central axis. It is a cross section which similarly shows a roller bearing. It is a perspective view which fractures | ruptures and shows a cage | basket similarly. It is a longitudinal section showing a cage similarly. It is an expanded view which similarly shows the pocket of a holder | retainer from an outer diameter side. It is explanatory drawing which shows the state which the holder | retainer moved to the direction where a centrifugal force acts similarly, and the protrusion contacted the internal peripheral surface of the center hole of a planetary gear. It is explanatory drawing which shows the embodiment in which the protrusion which can contact the inner peripheral surface of the center hole of a planetary gear was formed in the axial direction both ends of the several pillar part of a holder | retainer. It is a perspective view which shows the other embodiment of the protrusion formed in the several pillar part of a holder | retainer.

  The best mode for carrying out the present invention will be described in accordance with an embodiment.

A first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory diagram showing a simplified planetary gear mechanism according to Embodiment 1 of the present invention. FIG. 2 is a longitudinal sectional view showing a state in which the roller bearing is assembled between the planetary gear and the central shaft. FIG. 3 is a cross-sectional view showing the roller bearing. FIG. 4 is a perspective view showing the cage broken. FIG. 5 is a longitudinal sectional view showing the cage. FIG. 6 is a development view showing the pocket of the cage from the outer diameter side. FIG. 7 is an explanatory view showing a state in which the cage moves in the direction in which the centrifugal force acts and the protrusion comes into contact with the inner peripheral surface of the center hole of the planetary gear.

As shown in FIG. 1, a planetary gear mechanism 1 employed in an automatic transmission of an automobile includes a sun gear (sun gear) 2, a ring gear 3, and a plurality of (three in FIG. 1) planetary gears (planetary gears) as is well known. 4 is configured.
As shown in FIG. 2, the planetary gear 4 is rotatably supported on the outer periphery of the center shaft 6 assembled to the carrier 8 via a roller bearing (including a needle roller bearing) 10.
The planetary gear 4 revolves around the sun gear 2 while rotating around the central axis 6 while the sun gear 2 and the ring gear 3 mesh with each other.

  As shown in FIGS. 2 and 3, the roller bearing 10 has an annular clearance between the inner ring surface of the center hole 5 of the planetary gear 4 and the outer ring surface of the center shaft 6 as the inner ring track. Are provided with a plurality of rollers 11 and a retainer 20 that holds the plurality of rollers 11 in a rollable manner.

As shown in FIGS. 4 to 6, the retainer 20 connects both the annular portions 21 spaced apart from each other in the axial direction, and connects both the annular portions 21, and individually accommodates the plurality of rollers 11. A plurality of column portions 30 for defining a plurality of pockets 25 are integrally provided.
As shown in FIGS. 4 and 5, the plurality of column portions 30 of the retainer 20 include an axial intermediate portion 31 having a smaller diameter than the pitch circle (PCD) dimension of the plurality of rollers 11, and the plurality of rollers 11. Both end portions 32 in the axial direction having a diameter larger than the pitch circle dimension, and inclined connection portions 35 that connect the intermediate portion 31 in the axial direction and both end portions 32 in the axial direction are provided. Then, both axial end portions 32 of the plurality of column portions 30 are continuous with the same diameter as the two annular portions 21.
Further, in order to prevent the rollers 11 in the respective pockets 25 from coming off, the end surfaces of the axially intermediate portion 31 and the axially opposite end portions 32 of the opposing surfaces of the adjacent column portions 30 face each other toward the inside of the pocket 25. The retaining claws 40 and 41 projecting to the left are respectively projected.

As shown in FIGS. 4 to 6, the retainer 20 has a larger outer diameter than the outer peripheral surface of the retainer 20 (the outer peripheral surface of both annular portions 21 in the first embodiment). A protrusion 45 that protrudes and can contact the inner peripheral surface of the center hole 5 of the planetary gear 4 is integrally provided.
In the first embodiment, the protrusions 45 are each formed in a cut-and-raised shape with cut grooves 46 at both end edges in the axial direction among the peripheral portions of the plurality of pockets 25. And each protrusion 45 is scattered in the circumferential direction.

The cage 20 is formed by punching a plurality of pockets 25 at predetermined positions on a flat steel plate and thereafter bending the flat steel plate into a cylindrical shape. The
Further, when the plurality of pockets 25 are formed by punching the press, both end portions in the axial direction of the plurality of pockets 25 are cut and raised by the cut grooves 46 to form the protrusions 45.

In the roller bearing of the planetary gear mechanism according to the first embodiment configured as described above, the centrifugal force when the planetary gear 4 revolves around the gear of the sun gear 2 while rotating around the axis of the central shaft 6. Is received by the cage 20, the cage 20 moves in the direction in which the centrifugal force acts (direction of arrow P in FIG. 7).
At this time, it contacts the inner peripheral surface of the center hole 5 of the planetary gear 4 with a small contact area of the protruding end 45 a of the protrusion 45 protruding from the outer peripheral surface of the cage 20.
As a result, the outer peripheral surface of the cage 20 (in this embodiment 1, the outer peripheral surfaces of the two annular portions 21 and the axial end portions 32 of the column portions 30) contact the inner peripheral surface of the center hole 5 of the planetary gear 4. Is avoided. For this reason, the sliding resistance of the cage 20 can be kept small, and as a result, torque loss due to the sliding resistance of the cage 20 can be suppressed.

Further, in the first embodiment, when the plurality of pockets 25 are formed at predetermined positions on the flat steel plate by stamping, the both ends of the plurality of pockets 25 in the axial direction are cut and raised so that the projections 45 can be easily formed. Can be formed.
Further, since the projections 45 are formed in a cut-and-raised shape with cut grooves 46 at both axial ends of the plurality of pockets 25, as shown in FIG. 2, the planetary gear 4 from the opening 7 a of the oil hole 7 of the center shaft 6. The lubricating oil supplied toward the center hole 5 flows toward the inner peripheral surface of the center hole 5 of the planetary gear 4 and both axial edges of the cage 20 through the gaps of the cut grooves 46 of the protrusions 45. For this reason, the flow of lubricating oil becomes smooth.

In addition, this invention is not limited to the said Example 1, In the range which does not deviate from the summary of this invention, it can also be implemented with a various form.
For example, in the first embodiment, the case where the protrusions 45 are formed at both axial end portions of the plurality of pockets 25 (the portions where the two annular portions 21 face each other) is illustrated. However, as shown in FIG. The protrusions 145 may be formed at both end portions 32 in the axial direction of the portion 30.
Even in this case, when the plurality of pockets 25 are formed at predetermined positions on the flat steel plate by stamping, the opposite portions of the axial end portions 32 of the plurality of column portions 30 are cut by the cut grooves 146. As a result, the protrusion 145 can be easily formed.
Further, the lubricating oil supplied from the opening 7 a of the oil hole 7 of the center shaft 6 toward the center hole 5 of the planetary gear 4 passes through the cut groove 146 of the projection 145 to the inner peripheral surface of the center hole 5 of the planetary gear 4. The flow of lubricating oil is smoothed.
In addition, the present invention can be implemented even if a protrusion that can contact the inner peripheral surface of the center hole 5 of the planetary gear 4 is formed on a part of the outer end in the axial direction of both annular portions 21 of the cage 20.
Further, as shown in FIG. 9, in the cage 20 having both the annular portions 21, the plurality of column portions 30, and the plurality of pockets 25, when the plurality of pockets 25 are formed by punching a press, a plurality of pockets 25 are formed. The protrusions 245 can be formed by press caulking without forming notch grooves at both ends in the axial direction of the pocket 25. In this case, the present invention can be implemented.

DESCRIPTION OF SYMBOLS 1 Planetary gear mechanism 2 Sun gear 3 Ring gear 4 Planetary gear 5 Center hole 6 Center shaft 10 Roller bearing 11 Roller 20 Cage 21 Both annular parts 25 Pocket 30 Pillar part 45 Protrusion

Claims (3)

A roller bearing comprising a plurality of rollers and a cage assembled between a central hole and a central shaft of a planetary gear of a planetary gear mechanism,
The retainer includes a plurality of pillars that define both a plurality of annular portions arranged at predetermined intervals in the axial direction, and a plurality of pockets that individually connect the plurality of rollers and that respectively accommodate the plurality of rollers. With
The retainer is integrally provided with a protrusion that protrudes to a circumference having an outer diameter larger than the outer diameter of the retainer and that can contact the inner peripheral surface of the center hole of the planetary gear. A roller bearing of a planetary gear mechanism, characterized in that A roller bearing of the planetary gear mechanism according to claim 1,
A roller bearing for a planetary gear mechanism, wherein the protrusions are formed in a cut-and-raised shape around a plurality of pockets and are scattered in the circumferential direction. A roller bearing of the planetary gear mechanism according to claim 1,
A roller bearing for a planetary gear mechanism, wherein the protrusions are formed in cut-and-raised shapes at both ends in the axial direction around the plurality of pockets and are scattered in the circumferential direction.

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