JP2001208104A - Ratchet type one way clutch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ratchet type one way clutch constructed to reduce the resistance produced in a claw when slipping. SOLUTION: In a ratchet type one way clutch which is provided with a outer ring which has a pocket on inner periphery, a inner ring which is coaxially arranged with the outer ring and has a notch along a outer periphery, a claw which is secured in the pocket and transfer a torque between the inner ring and outer ring, and an elastic body which energizes the claw to the inner ring, a centroid of the claw is arranged at the elastic body side against a operation center of the claw, so as to be tightly pressed on an internal surface of the pocket when number of rotation is equal or higher than given number of rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ratchet type one-way clutch used as a component for torque transmission, backstop and the like in a drive unit of an automobile (in particular, an automatic transmission for an automobile) or an industrial machine. is there.

[0002]

2. Description of the Related Art Generally, a clutch incorporated in a part of an automatic transmission for a motor vehicle connects and disconnects power transmission from an engine to a drive system between a drive shaft and a driven shaft.
For example, there are various types such as a ratchet type and a sprag type one-way clutch.

[0003] The sprag type one-way clutch is provided with an annular outer ring and an annular inner ring arranged in the outer ring which are radially separated and concentrically arranged so as to be relatively rotatable, and an inner ring and an outer ring which are arranged between the outer ring and the inner ring. A plurality of sprags that transmit torque between the sprags, an annular retainer that retains the sprags, a spring member that retains the sprags together with the retainers and urges the sprags in a meshing direction, and retains the retainers in the axial direction And an annular retainer fixed to either the inner ring or the outer ring. In this configuration, when the outer ring idles at a predetermined rotational speed or more, there is an effect that the torque transmitting member, that is, the sprag is separated from the sliding surface, and the drag torque during the idle rotation is cut off.

[0004] However, if the technology of the sprag type one-way clutch is directly applied to the ratchet type one-way clutch, the torque transmitting member, that is, the claw body vibrates in the pocket, and a worn portion is generated in the pocket, and abnormal noise is easily generated. . As a result, the durability of the ratchet type one-way clutch is inferior.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention suppresses the vibration of the pawl body, which is a torque transmitting member, so that a worn portion does not occur in the pocket during idling, and the pawl body securely adheres to the inner surface of the pocket. To provide a ratchet-type one-way clutch that reduces the sliding resistance when the pawl body slides on the outer peripheral surface of the inner ring and suppresses the generation of abnormal noise. I do.

It is another object of the present invention to reduce the contact area between the axial side surface of the claw body and a surface facing the claw body, thereby reducing the viscous resistance of lubricating oil. An object of the present invention is to provide a ratchet type one-way clutch having excellent durability.

[0007]

In order to achieve the above object, a ratchet type one-way clutch according to the present invention comprises an outer ring having a pocket on the inner periphery, an inner ring substantially concentric with the outer ring and having a notch on the outer periphery, A claw body for transmitting torque between the inner ring and the outer ring, which is housed in the pocket, is constituted by an elastic body for urging the claw body toward the inner ring, and the center of gravity of the claw body is It is located on the elastic body side with respect to the operating center of the claw body.
The claw body is configured to substantially adhere to the inner surface of the pocket.

Further, in the ratchet type one-way clutch according to the present invention, the bottom surface of the claw body facing the outer peripheral surface of the inner ring has an arc shape complementary to the outer peripheral surface of the inner ring.

Further, in the ratchet type one-way clutch according to the present invention, a connecting portion between the outer peripheral surface of the inner race and the notch and a valley bottom of the notch have an arc shape.

In the ratchet type one-way clutch according to the present invention, an axial side portion of the claw body is supported by the projection.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an outer race having a pocket on the inner periphery, an inner race arranged substantially concentrically with the outer race and having a notch on the outer periphery, and an inner race housed in the pocket and between the inner race and the outer race. A ratchet-type one-way clutch constituted by a claw body for transmitting torque and an elastic body for urging the claw body toward the inner ring, and a center of gravity of the claw body with respect to an operating center of the claw body. The claw body is configured to be substantially in close contact with the inner surface of the pocket at a predetermined rotation speed or more.

As the elastic body, a coil spring, a garter spring, a wave spring or the like can be used. The bottom surface of the claw body facing the outer peripheral surface of the inner ring has an arc shape complementary to the outer peripheral surface of the inner ring.

Further, a connecting portion between the outer peripheral surface of the inner race and the notch and a valley bottom of the notch are arc-shaped.

[0014] Further, an axial side portion of the claw body is supported by a projection. It is most effective that the protrusion is provided so as to support the operating center of the claw body.

[0015]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The same parts are denoted by the same reference numerals in each drawing. FIG. 1 is a front view of a ratchet type one-way clutch which is an example of a device for carrying out the present invention, which will be described below.

The ratchet type one-way clutch 1 is used for a stator of a torque converter for an automatic transmission. The annular outer ring 30 is integrally formed with the stator wing portion 33, and three pockets 31 for accommodating the claw body 40 are arranged at equal intervals in the circumferential direction on the inner circumference, and are opened on the inner circumference. ing. Further, inside each pocket 31, there are provided a coil spring 50 for urging the claw body 40 inward in the radial direction and a spring pocket (recess) 32 for accommodating an elastic member such as a wave spring. I have. It is needless to say that the arrangement and the number of the outer ring pockets and coil springs are not limited to those of the embodiment and can be arbitrarily changed.

An annular inner ring 20 is disposed substantially concentrically with the outer ring 30 radially inward of the inner peripheral surface of the outer ring 30.
The inner ring 20 is provided with a plurality of notches 22 on its outer periphery in the circumferential direction for fitting with the claws 40b of the claw body 40, and has splines 21 on its inner peripheral surface for fitting with a shaft (not shown). . It is needless to say that the number and arrangement of the notches and splines are not limited to the present embodiment and can be arbitrarily changed.

Referring to FIG. 2, the structure of the ratchet type one-way clutch 1 of the present invention will be further described. FIG. 2 is an axial cross-sectional view along the line AA of FIG. As shown in the drawing, the pocket 31 includes an upper surface 56 of the outer race 30 and a wall surface 31b substantially perpendicular to the upper surface 56, and a portion of the wall surface 31b facing the axial direction is open. A claw body 40 is arranged in the pocket 31 so as to be swingable in the radial direction of the inner ring 20.

An annular side plate 90 having a substantially L-shaped cross section is interposed between the inner race 20 and the outer race 30. Side plate 9
0 is provided with a convex portion 94 on the plate portion 97,
It is dimensioned so that it can fit into the opening of the pocket 31.
The side plate 90 prevents the claw body 40 from slipping outward in the axial direction.

A protruding portion 99 protruding outward in the axial direction extends from one end of the plate portion 97, and a substantially vertical corner defined by the plate portion 97 and the protruding portion 99 and an axially outer portion of the outer ring. A needle bearing member 70 is mounted on each side surface. That is, the axial end of the ratchet type one-way clutch 1 is supported by the needle bearing.

Further, on the inner periphery of the step portion 38 of the outer race 30,
A groove 38a for a snap ring is engraved.
By attaching the snap ring 80 to the side plate 90, the side plate 90 is prevented from coming off outward in the axial direction.

In the ratchet type one-way clutch 1 configured as described above, the outer ring 30 can rotate only in one direction with respect to the inner ring 20 (clockwise in FIG. 1). For example,
When the outer ring 30 rotates forward (clockwise in FIG. 1), the claw body 4
0 slides on the outer periphery of the inner ring 20. On the other hand, when the outer ring 30 rotates in the reverse direction (counterclockwise in FIG. 1), the claw 40b of the claw body 40 is housed in the notch 22 provided on the outer periphery of the inner ring 20 to be in a locked state. Transmits torque.

Next, the ratchet type one-way clutch of the present invention in the case where the outer wheel 30 runs idle (ie, rotates forward) with respect to the inner wheel 20 will be described. FIG. 3 shows a line B in FIG.
FIG. 4 is a partial cross-sectional view taken along a line B-B, showing an arrangement of the claw body 40 in the pocket 31 in a state where the outer ring 30 has reached a predetermined number of revolutions. In the figure, the center of gravity of the nail body 40 is indicated by X,
As the outer ring 30 rotates, centrifugal force acts radially outward (in the direction of the arrow) on the claw body.

On the other hand, the center of operation (oscillation) of the claw body 40 substantially coincides with the portion supported by the projection 93. Therefore,
The center of gravity X of the claw body 40 is arranged on the side closer to the coil spring 50 with respect to the operating center.

The pocket 31 has an engaging surface 58 extending in the radial direction of the outer ring 30, an upper surface 56 extending in the circumferential direction from the engaging surface 58, and an inclined surface 54 inclined from the upper surface 56 in the inner ring direction. , The holding surface 62 inclined from the inclined surface 54 in the inner ring direction
It is composed of Further, the rear surface 42 is connected to the inner peripheral surface 37.

Further, a spring pocket 32 is provided in the pocket 31 so as to open radially away from the inclined surface 54 and the holding surface 62 of the pocket 31. In the spring pocket 32, one end of the coil spring 50 is disposed so as to contact the inclined surface 43 and the rear surface 42 of the claw body 40, and the other end of the coil spring 50 is
Abuts the hemispherical wall surface 33 of With this configuration, the biasing force of the coil spring 50 is always applied radially inward to the claw body 40, and when the outer ring is not rotating, the sliding surface (bottom surface) 41 of the claw body 40 is Abuts the outer periphery of

In this configuration, when the outer ring 30 rotates forward and reaches a predetermined number of revolutions, the centrifugal force generated in the claw body 40 becomes larger than the urging force of the coil spring 50, and the claw 40b of the claw body 40 moves around the operation center. Swings and jumps up in the outer ring direction.
That is, the sliding state between the sliding surface 41 of the claw body and the outer periphery of the inner ring 20 is released, and the inclined surface 43 and the rear surface 42 of the claw body are formed in the pocket 3.
The first inclined surface 54 and the holding surface 62 are in contact with each other.

In order to prevent the claw body 40 from vibrating inside the pocket 31 and the pocket and the claw body from being worn, the inclined surface 54, the rear surface 42 of the pocket and the inclined surface 43 of the claw body opposed to each other. The rear surfaces 42 were shaped so as to be substantially in close contact with each other.

With this configuration, when the outer ring 30 is idling (clockwise), the centrifugal force acting on the claw body 40 holds the outer ring 30 in the pocket while being securely pressed against the inclined surface 54 and the holding surface 62 of the pocket 31. Thus, the vibration of the claw body 40 in the pocket 31 is suppressed when the outer ring idles at a predetermined rotation speed or more.

FIG. 4 is a side view of the claw body 40 shown in FIG. The claw body 40 has, in addition to the rear surface 42 and the inclined surface 43 described above, an upper surface 44 inclined from the inclined surface 43 toward the inner ring.
A front surface 45 extending from the upper surface 44 substantially in parallel to the rear surface 42 in the inner ring direction, and the front surface 45 and the rear surface 42 are connected to each other to form the inner ring 20.
And a sliding surface 41 extending opposite to the outer periphery of the first member, and an arc surface 46 having a predetermined radius of curvature is interposed between the adjacent surfaces. Further, the sliding surface 41 has a radius of curvature R1 substantially equal to the sliding surface 26 of the inner race as described above. Furthermore, the claw body 40 has two substantially parallel axial end faces 40.
a, 40c (see FIG. 6).

According to the structure of the present invention, the sliding resistance between the sliding surface 41 of the claw body and the outer periphery of the inner ring 20 is reduced, the impact due to repeated contact with the notch 22 is reduced, and the sliding surface 41 is separated. It becomes difficult.

FIG. 5 is a partial sectional view of the inner race 20 shown in FIG. The outer periphery of the inner ring 20 has a sliding surface 26 and a vertical surface 23 which constitutes the notch 22 and extends radially inward from the sliding surface, and an inclined surface 24 which inclines radially outward from the vertical surface 23. ing. The vertical surface 23 and the inclined surface 24 are connected by an arc surface (valley bottom) 25. In this embodiment, the arc surface 25 is formed by the rear surface 42 of the claw body 40 and the sliding surface 41.
Have a radius of curvature substantially the same as that of the arc surface 46 connecting the.

The vertical surface 23, the sliding surface 26, the inclined surface 2
4 and the sliding surface 26 are connected by an arc surface 28 having a radius of curvature R3 and an arc surface 27 having a radius of curvature R2, respectively.

By forming the outer periphery of the inner ring 20 in this configuration, the sliding resistance generated when the claw body 40 slides on the outer periphery with the rotation of the outer ring 30 is reduced, and the sliding surface 41 of the claw body 40 is reduced.
The impact caused by repeated contact between the nail and the outer periphery is reduced,
Of the sliding surface 41 hardly occurs.

FIG. 6 is a partially enlarged view of the ratchet type one-way clutch 1 shown in FIG. The figure shows the nail 40
It can be seen that the axial side surfaces 40a, 40c are supported by the projections 35, 93. The projection 35 is formed integrally with the wall surface 31 b of the pocket 31 of the outer ring 30,
The protrusion 93 is formed integrally with the side plate 90.

By providing the projections 35 and 93, the contact area of the side surfaces 40a and 40c of the claw body 40 with the wall surfaces 31b and 90b can be reduced, and the viscous resistance generated on the claw body 40 by the lubricating oil can be reduced. Can be. Further, it is most effective to arrange the projections 35 and 93 so as to support the operating center of the claw body 40.

It is needless to say that the embodiments described above are described as examples of the present invention and do not limit the present invention.

[0038]

According to the ratchet type one-way clutch of the present invention, there is an effect that the resistance to the pawl body during idling is reduced and abnormal noise is suppressed, and the durability of the ratchet type one-way clutch can be improved.

Specifically, the claw body and the inner surface of the pocket are formed in such a shape as to be in close contact with each other, and when the outer ring rotates at a predetermined rotation speed or more, the claw body and the inner surface of the pocket are brought into close contact with each other due to centrifugal force. Vibration is suppressed.

Further, by making the sliding surface of the claw body and the outer periphery of the opposed inner ring complementary, the impact due to repeated contact between the claw body and the notch is reduced, and the sliding surface of the claw body is reduced. Peeling is less likely to occur.

Further, by connecting the notch provided on the outer periphery of the inner ring and the sliding surface with an arcuate surface, the impact due to repeated contact between the claw and the notch is reduced, and the sliding surface of the inner ring is less likely to peel. .

Protrusions are provided on the surface of the claw body facing the axial side surface, so that the contact area of the side surface can be reduced, and the viscous resistance due to lubricating oil can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view showing a ratchet type one-way clutch according to the present invention.

FIG. 2 is an axial sectional view taken along line AA of FIG. 1;

FIG. 3 is a partial cross-sectional view of the ratchet type one-way clutch of the present invention in an idling state.

FIG. 4 is a side view of a pawl used in the ratchet type one-way clutch of the present invention.

FIG. 5 is a partial sectional view of an inner race used in the ratchet type one-way clutch of the present invention.

FIG. 6 is a partial sectional view taken along line BB of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ratchet type one-way clutch 20 Inner ring 30 Outer ring 31 Pocket 32 Spring pocket 40 Claw body 50 Coil spring 90 Side plate

Continuation of the front page (72) Inventor Kazuhiko Muramatsu 2345 Aino, Fukuroi-shi, Shizuoka Prefecture NSK Warner Co., Ltd.

Claims (4)

[Claims] 1. An outer ring having a pocket on an inner periphery, an inner ring having a notch on an outer periphery substantially concentric with the outer ring,
A ratchet-type one-way clutch, which is housed in the pocket and configured by a claw body for transmitting torque between the inner ring and the outer ring, and an elastic body for urging the claw body toward the inner ring; A ratchet characterized in that the center of gravity of the claw body is located on the elastic body side with respect to the operating center of the claw body, and the claw body is configured to be substantially in close contact with the inner surface of the pocket at a predetermined rotational speed or more. Type one-way clutch. 2. A ratchet type one-way clutch, wherein a bottom surface of the claw body facing an outer peripheral surface of the inner ring has an arc shape complementary to the outer peripheral surface of the inner ring. 3. A ratchet-type one-way clutch, wherein a connecting portion between the outer peripheral surface of the inner race and the notch and a valley bottom of the notch are arc-shaped. 4. A ratchet-type one-way clutch, wherein an axial side portion of the claw body is supported by a projection.