JP2007092866A - Sprag type one-way clutch and retainer therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a retainer having a flange capable of preventing the inside surface of the flange from deforming into an elliptical shape when the flange is press-fitted into an outer ring. <P>SOLUTION: The annular flange 9b of this retainer for one-way clutch stretching outward in the radial direction from the side end of a cylindrical body 9a furnished with a sprag holding hole 9c has such an elliptical shape that the longer axes of its outside surface 9d and inside surface 9e are identical before the outer ring is press-fitted, and after fitting, the flange outside surface 9d is deformed into an elliptical shape with the long axis radius is shortened while the flange inside surface 9e is deformed from elliptical shape to approximately circular shape. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a retainer for a sprag type one-way clutch and a sprag type one-way clutch. A power transmission device including a sprag type one-way clutch is incorporated in an automobile pulley unit, an automatic transmission, an engine starter, or the like. Such a sprag type one-way clutch includes a sprag interposed between a radially outer member (outer ring) on one side of the drive side or the driven side and a radially inner member (inner ring) on the other side. This is a one-way clutch that transmits the rotational power of one side of the outer ring and the inner ring to the other side or blocks the transmission by the tilting motion of the sprag according to the relative rotation between the inner ring and the inner ring. The sprag is engaged with the outer ring and the inner ring, and the two wheels are connected to each other in an integrally rotating state so that the rotational power is transmitted (locked), and the engagement is released and the rotational power transmission is interrupted (free state). To do.

  Some sprag-type one-way clutches include an outer cage, an inner cage, a sprag, and a ribbon spring. Both cages and ribbon springs are provided with a plurality of sprag holding holes in the circumferential direction. The sprag is seen from a side view from an outer diameter portion that engages with the inner diameter surface of the outer ring by frictional contact, an inner diameter portion that engages with the outer diameter surface of the inner ring by friction contact, and a body portion between the outer diameter portion and the inner diameter portion. It has a bowl shape. Such sprags are mounted in the sprag holding holes of the outer cage, the ribbon spring, and the inner cage. The ribbon spring urges the sprags in a direction in which the sprags are bitten into the outer ring and the inner ring. In the sprag type one-way clutch having such a configuration, for example, when the outer ring rotates relative to the inner ring in a clockwise direction, for example, the sprag is engaged with the outer ring and the inner ring, and the inner and outer rings are locked. . When the outer ring rotates relative to the inner ring, for example, in the counterclockwise direction, the sprag is released from the above-described engagement, and the inner and outer rings are in a free state.

  In such a one-way clutch, when used as a power transmission device incorporated in the above-mentioned automobile auxiliary machinery, the outer ring or the like is used so that the clutch function is not impaired by vibration, inertia, etc. The inner ring is fixed with a constant drag torque. For example, when the outer ring is suddenly accelerated or decelerated, the sprag slides on the outer ring raceway due to inertia, so by applying drag torque between the outer cage and the outer ring to always rotate the cage and the outer ring integrally, The sprags are reliably operated by promptly transmitting them to the outer cage in response to the sudden acceleration or deceleration of the outer ring.

In order to fix such a cage to the outer ring so as to be dragged with a constant drag torque, the cage extends radially outward to the axial side end of the cylindrical body and a sprag holding hole. The outer diameter surface of the outer ring surface is press-fitted into the inner diameter surface of the outer ring, and the drag torque described above is applied. A sprag type one-way clutch has been proposed (see Patent Document 1). However, in the case of this collar part, when the cage is not press-fitted into the outer ring, the outer diameter surface is elliptical, whereas the inner diameter surface is circular. The inner diameter surface of the portion is deformed into an elliptical shape, and the deformation of the inner diameter surface of the flange portion reaches the cylindrical main body of the cage, and the cylindrical main body is deformed into an elliptic shape. If the cylindrical body is deformed into an oval shape, the multiple sprag holding holes in the circumferential direction of the cylindrical body are in the circumferential direction, and the gap between the sprags is wide and narrow, and the movement of the sprags is loosened more than necessary. And a place where it is regulated more than necessary. Also in the ribbon spring, there are places where the gaps between the sprag holding holes in the circumferential direction and the sprags differ widely in the circumferential direction, and the urging action of the ribbon spring against the sprags is different. As a result, the sprags cannot be evenly arranged in the circumferential direction in the sprag holding holes, and the locking state of the sprags with respect to the outer ring and the inner ring is changed, resulting in a lower locking function. It will affect the life.
Japanese Utility Model Publication No. 62-188632

  An object of the present invention is to provide a cage that can be fixed to an outer ring so as to be integrally rotatable, and at the same time, ensures the functions of a sprag and a ribbon spring as expected.

  A sprag type one-way clutch retainer according to the present invention includes an annular flange extending radially outward from a side end of a cylindrical body having a plurality of sprag holding holes in the circumferential direction, and the flange outer diameter A sprag type one-way clutch retainer having an elliptical surface, wherein the flange has an elliptical shape in which both the outer diameter surface of the flange and the inner diameter surface of the flange coincide with each other before the outer ring is press-fitted. After the outer ring is press-fitted, the collar outer diameter surface is deformed into an ellipse whose major axis radius is shortened, and the collar inner diameter surface is deformed from an ellipse to a substantially circular shape. .

  According to the present invention, even if the inner diameter surface of the collar portion is elliptical when the cage is not press-fitted into the outer ring, the major axis side coincides with the elliptical major axis of the outer diameter surface, and the cage is To provide a cage in which the above-mentioned conventional problems due to the fact that the inner diameter surface of the collar portion is elliptical when the collar portion is press-fitted into the outer ring, since it is circular when pressed into the outer ring. Can do.

  In the case of the present invention, the number of cages arranged in the sprag type one-way clutch may be one or a plurality of two or more, and in the case of two cage configurations of an inner cage and an outer cage, A flange can be provided at the side end of the outer cage. In the case of the present invention, the cage is not limited to the material, and may be made of metal, resin, or the like. The cage can be composed of an outer cage and an inner cage, and a flange can be provided at the side end of the inner cage.

  The cage of the present invention is applied to either an outer ring which is a member on one side of driving or driven arranged radially outside or an inner ring which is a member on the other side of driving or driven arranged radially outside. Can be press-fitted. The shapes of the outer ring and the inner ring are not limited to a cylindrical shape, and can be formed in various shapes according to the usage mode of the device in which the one-way clutch is incorporated. The inner ring may be a solid or hollow rotating shaft.

  In the present invention, on the side surface of the flange portion, on the elliptical long axis which is the shape of the outer diameter surface and the inner diameter surface in a state where the retainer is not press-fitted into the outer ring, the penetration for reducing the rigidity of the flange portion It is preferable to provide a hole. The collar part is extremely large with respect to the outer ring because it deforms the outer diameter surface of the ellipse to give the outer ring inner surface and fastening allowance to fix the cage to the inner surface of the outer ring and rotate integrally with the outer ring. Integrated with a fixed force. For this reason, when the outer ring and the flange do not slide relative to each other, the sprag always repeats the engagement with the inner diameter surface portion (local portion) of the outer ring inner diameter surface and the release of the engagement. There is a possibility that the local portion is worn out, causing a biting failure, and the transmission of the rotational power (locked state) cannot be performed. Therefore, if the through hole is provided in the flange, the rigidity of the entire cage is lowered, and the cage can be rotated integrally with the outer ring, while the relative sliding between the outer ring and the flange occurs even slightly. It becomes possible to manage the fixing force for fixing the cage to the outer ring, to suppress the above-mentioned extreme wear at the local portion, and to improve the life of the one-way clutch provided with the cage. .

  ADVANTAGE OF THE INVENTION According to this invention, the holder | retainer which can be fixed to an outer ring | wheel so that integral rotation is possible, and ensures the function of a sprag or a ribbon spring as expected can be provided.

  Hereinafter, a sprag type one-way clutch retainer according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  First, with reference to FIG. 1, the one-way clutch provided with the holder | retainer of embodiment and the power transmission device provided with this one-way clutch are demonstrated. This power transmission device includes an outer ring 1 that is a power transmission wheel, an inner ring 3 that is a power transmitted wheel, and a sprag type one-way clutch 5 that mediates transmission of power between both wheels 1 and 3. The one-way clutch 5 includes a plurality of sprags 7 arranged at equal intervals in the circumferential direction between the inner and outer rings 1, 3, an annular outer cage 9 that holds an outer diameter portion of the sprags 7, and an inner diameter of the sprags 7. And an annular ribbon spring 13 disposed between the outer cage 9 and the inner cage 11 to urge the sprag 7 toward the lock side. The outer retainer 9 includes a cylindrical main body 9a extending in the axial direction and a flange 9b extending outward in the radial direction from a side end on one axial side of the cylindrical main body 9a. The cylindrical main body 9a has sprag holding holes 9c at equal intervals in the circumferential direction. The inner cage 11 includes a cylindrical main body 11a extending in the axial direction and a flange portion 11b extending inward in the radial direction from a side end on one axial side of the cylindrical main body 11a. The cylindrical main body 11a has sprag holding holes 11c at equal intervals in the circumferential direction. The ribbon spring 13 has a sprag holding hole 13a.

  As described above, in the embodiment, the flange portion 9b of the outer retainer 9 includes the flange outer diameter surface 9d and the flange inner diameter surface 9e, and before being pressed into the outer ring 1, the flange outer diameter surface 9d. Both the inner diameter surface 9e of the flange portion has an elliptical shape whose major axis coincides, and after being press-fitted into the outer ring 1, the outer diameter surface 9d of the flange portion is deformed into an elliptical shape whose major axis radius is shortened and the inner diameter surface of the flange portion 9e is provided with a shape that deforms from an elliptical shape to a substantially circular shape.

  Hereinafter, the outer retainer 9 will be described in detail with reference to FIGS. 2 to 4. 2 is a side view of the outer retainer 9 before being press-fitted into the outer ring 1 as viewed from the flange 9b side, and FIG. 3 is a side view of the outer retainer 9 as it is pressed into the outer ring 1 as viewed from the flange 9b. FIG. 4 and FIG. 4 are diagrams for explaining the deformation of the flange portion 9b before and after the flange portion 9b is press-fitted into the outer ring 1.

  The flange 9b of the outer retainer 9 extends radially outward from the side end of the cylindrical main body 9a, and the flange outer diameter surface 9d and the flange inner diameter surface 9e both have an elliptical shape whose major axis sides coincide. Yes. The major axis radius of the flange outer diameter surface 9d at this time is RoutL, and the minor axis radius is RoutS. The major axis radius of the flange inner diameter surface 9e is RinL, and the minor axis radius is RinS.

  When the flange 9b is press-fitted into the outer ring 1, the elliptical long axis side region of the flange outer diameter surface 9d contacts the outer ring inner diameter surface 1a. As a result, the flange outer diameter surface 9d is compressed so that its major axis radius decreases from the major axis radius RoutL before press-fitting to the major axis radius RoutL ′ after press-fitting, and from the minor axis radius RoutS before press-fitting, the shorter after press-fitting. The shaft radius increases to RoutS ′. In this case, the collar outer diameter surface 9d is set in an elliptical shape in which the major axis radius RoutL ′ after press-fitting is larger than the minor axis radius RoutS ′ after press-fitting, and the collar outer diameter surface 9d is press-fitted. The oval shape is maintained afterwards. This relationship is shown in the following equations (1) to (3).

RoutL−RoutL ′ = ΔLout (1)
RoutS′−RoutS = ΔSout (2)
RoutL ′> RoutS ′ (3)
In the above formulas, when formulas (1), (2), and (3) are simultaneously established, the collar outer diameter surface 9d maintains an elliptical shape, although the major axis and minor axis radii change before and after press-fitting. As described above, in the embodiment, regarding the flange outer diameter surface 9d, the value RoutL ′ obtained by subtracting the major axis radius decrease amount ΔLout from the major axis radius RoutL before press-fitting increases the minor axis radius from the minor axis radius RoutS before press-fitting. The elliptical shape of the flange outer diameter surface 9d before press-fitting is set so as to be larger than the value RoutS ′ obtained by adding the amount ΔSout.

  On the other hand, the inner diameter surface 9e of the flange portion has a major axis radius that decreases from the major axis radius RinL before press-fitting to the major axis radius RinL ′ after press-fitting and the minor axis radius RinS ′ after press-fitting from the minor axis radius RinS before press-fitting. Become bigger. The flange inner diameter surface 9e is set so that the major axis radius RinL ′ after press-fitting is relatively close to the minor axis radius RinS ′ after press-fitting and these are equal. Therefore, the flange inner diameter surface 9e becomes circular after press-fitting. This relationship is shown in the following equations (4) to (6).

RinL−RinL ′ = ΔLin (4)
RinS′−RinS = ΔSin (5)
RinL ′ = RinS ′ (6)
Based on the above relationship, the flange inner diameter surface 9e has an elliptical shape before press-fitting so that the expression (6) is satisfied. That is, in the embodiment, the value RinL ′ obtained by subtracting the major axis radius decrease amount ΔLin from the major axis radius RinL before press-fitting for the flange inner surface 9e is the minor axis radius increment ΔSin from the minor axis radius RinS before press-fitting. The elliptical shape before press-fitting of the flange inner diameter surface 9e is set so as to be equal to the value RinS ′ obtained by adding.

  As described above, the flange portion 9b of the embodiment has the oval shapes of the outer diameter surface 9d and the inner diameter surface 9e before press-fitting so that the above formulas (1) to (6) are satisfied.

  As described above, in the embodiment, the flange portion 9b has an outer diameter surface 9d and an inner diameter surface 9e having an elliptical shape whose major axis sides coincide with each other before the outer ring 1 is press-fitted so that the expressions (1) to (6) are satisfied. After the outer ring 1 is press-fitted, the flange outer diameter surface 9d is deformed into an oval shape whose major axis radius is shortened by contact with the outer ring 1, while the collar inner diameter surface 9e has a major axis radius and a minor axis radius. Can be deformed from an elliptical shape to a substantially circular shape. According to the embodiment, since the inner diameter surface 9e of the flange portion 9b is circular when the outer retainer 9 is press-fitted into the outer ring 1, the conventional inner diameter surface 9e is elliptical. The outer cage 9 in which various problems do not occur can be provided.

  As shown in FIG. 5, the rigidity of the flange portion 9 b is set on the side surface 9 f of the flange portion 9 b on the elliptical long axis of the flange outer diameter surface 9 d before the outer retainer 9 is press-fitted into the outer ring 1. By providing the through-hole 9g to be lowered, it is possible to manage the fixing force for fixing the outer cage 9 to the outer ring 1. The shape of the through hole 9g can be appropriately set according to the management of the fixing force, but is preferably, for example, an ellipse.

  In the above, the present invention is not limited to the above-described embodiment, but includes various modifications that do not exceed the scope of the claims.

It is sectional drawing of the power transmission device with which the one way clutch provided with the outer holder | retainer which is a holder | retainer concerning embodiment of this invention was integrated. It is the side view seen from the collar part side before the press fit in the outer ring | wheel of the outer retainer simple substance of FIG. It is the side view seen from the buttocks side after press-fitting in the outer ring | wheel of the outer holder | retainer of FIG. It is a figure for demonstrating the deformation | transformation before and behind the press fit to the outer ring | wheel of the outer cage of FIG. It is the side view which looked at the outer holder | retainer which concerns on other embodiment from the collar part side.

Explanation of symbols

1 Outer ring 3 Inner ring 5 One-way clutch 7 Sprag 9 Outer cage 11 Inner cage 13 Ribbon spring

Claims (3)

A sprag type unidirectional comprising an annular flange extending radially outward from a side end of a cylindrical body having a plurality of sprag holding holes in the circumferential direction, and the flange outer diameter surface is formed in an elliptical shape A clutch retainer,
The flange has an elliptical shape in which both the outer diameter surface of the flange and the inner diameter surface of the flange coincide with each other before the outer ring is press-fitted, and the ellipse in which the major axis radius is reduced after the outer ring is press-fitted. A sprag type one-way clutch retainer characterized by comprising a shape that deforms into a shape and has a shape in which a flange inner diameter surface deforms from an elliptical shape to a substantially circular shape.   The through-hole which lowers the rigidity of a collar part is provided in the side surface of the collar part on the elliptical long axis of the collar outer diameter surface before outer ring press-fit. Sprag type one-way clutch cage.   A sprag provided with a cage having a plurality of sprag holding holes in the circumferential direction, a plurality of sprags held in the sprag holding holes, and a spring for biasing the sprags into the outer ring and the inner ring A sprag type one-way clutch, characterized in that the cage is constituted by the cage according to claim 1 or 2.

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