JP2021046893A - Ratchet-type one-way clutch - Google Patents

Abstract

To provide a ratchet-type one-way clutch which can improve the stability of a behavior of a spring and the durability of the spring without needing a complicated attachment structure, and exerting a stable engagement behavior.SOLUTION: A ratchet mechanism has a plurality of claw members 3 arranged at an internal peripheral part of an outer ring 7, and arranged in a radial direction so as to be oscillatory, and a plurality of springs 19 formed at the internal peripheral part of the outer ring 7, arranged in a plurality of second recesses 21 which is opened toward the inside of the radial direction, and biasing the plurality of claw members 3 toward the inner ring 9 while contacting with faces 59 of the plurality of claw members 3 at an outside diameter side. A bottom face 63 of the second recess 21 is formed into a plain face, the faces 59 of the claw members 3 at the outside diameter side are formed into plain faces, and the bottom face 63 of the second recess 21 and the faces 59 of the claw members 3 at the outside diameter side are parallel to each other when the outer ring 7 and the inner ring 9 are in torque non-transmission states.SELECTED DRAWING: Figure 1

Description

The present invention relates to a ratchet type one-way clutch used as a torque transmission mechanism in a vehicle, an industrial machine, or the like.

Conventionally, in a ratchet type one-way clutch provided with a ratchet mechanism including a plurality of claw members which are torque transmission members and a notch or a tooth portion in which the claw member meshes, the meshing behavior of the claw member with respect to the notch or the tooth portion is stabilized. Therefore, a spring is used to urge the claw member to the notch or the tooth portion.

In recent years, in the one-way clutch used for an electrified drive device, the ratchet type one-way clutch as described above is often used in order to ensure the engagement of the torque transmission member at the time of high-speed rotation. In the ratchet type one-way clutch used for the electrified drive device, the meshing behavior of the claw member and the notch or the tooth part is due to the fact that it is used in the high rotation range of the electric motor and the complexity of the drive control. There is a need for further improvement in the stability of the.

Patent Documents 1 and 2 describe a ratchet type one-way clutch having improved stability of meshing behavior between a claw member and a notch.
Patent Document 1 describes a ratchet type one-way clutch in which the behavior of the claw member is stabilized and the claw member is prevented from coming out of the pocket to improve the meshing performance between the claw member and the notch of the inner ring. ..
Patent Document 2 describes that by attaching a coiled spring to an outer ring via a spring seat, one end of the spring is supported by a flat surface portion of the spring seat and the runout of the spring is suppressed.

Japanese Unexamined Patent Publication No. 2015-224744 JP-A-2017-101758

However, in Patent Document 1, since the shape of the tip of the claw member to which the coiled spring contacts is a curved surface having an arcuate cross section, the behavior of the spring in a high rotation range may become unstable. At the same time, there is a concern that the durability of the spring may decrease due to unstable behavior.
In Patent Document 2, one end of the spring is supported by the flat surface portion of the spring seat, but since the spring is attached to the inner peripheral portion of the outer ring via the spring seat, the number of parts increases and the spring attachment structure However, the number of man-hours required for assembly increases.

The present invention has been made in view of such a situation, and it is possible to improve the stability of the behavior of the spring and the durability of the spring without requiring a complicated mounting structure, and exhibit stable meshing behavior. An object of the present invention is to provide a ratchet type one-way clutch.

In order to solve the above problems, the ratchet type one-way clutch according to the present invention is
With the outer ring
An inner ring arranged coaxially with the outer ring and relatively rotatable inside the outer ring in the radial direction.
It has a ratchet mechanism capable of switching between the outer ring and the inner ring in a torque transmission state and a torque non-transmission state.
The ratchet mechanism includes a plurality of claw members provided on the inner peripheral portion of the outer ring and arranged so as to be swingable in the radial direction, and a plurality of claw members formed on the inner peripheral portion of the outer ring and opening inward in the radial direction. In a ratchet type one-way clutch, each of which is arranged in a recess and has a plurality of springs that come into contact with the outer diameter side surfaces of the plurality of claw members and urge the plurality of claw members toward the inner ring, respectively.
The bottom surface of the recess is formed flat, and the outer diameter side surface of the claw member is formed flat.
The bottom surface of the recess and the surface on the outer diameter side of the claw member are characterized in that the outer ring and the inner ring are parallel to each other when the torque is not transmitted.

According to the present invention, it is possible to improve the stability of the behavior of the spring and the durability of the spring without requiring a complicated mounting structure, and it is possible to provide a ratchet type one-way clutch exhibiting stable meshing behavior. ..

FIG. 1 is a front view showing a main part of the ratchet type one-way clutch according to the embodiment, and shows a non-meshing state between the claw member and the tooth part. FIG. 2 is a front view showing a main part of the ratchet type one-way clutch according to the embodiment, and shows only the outer ring and the inner ring part. FIG. 3 is a front view showing a main part of the ratchet type one-way clutch according to the comparative example.

Hereinafter, the ratchet type one-way clutch according to the embodiment of the present invention will be described with reference to the drawings.
First, the direction related to the ratchet type one-way clutch in this embodiment is defined. In the present embodiment, the axial direction, the radial direction, and the circumferential direction refer to the axial direction, the radial direction, and the circumferential direction with respect to the central axis of the ratchet type one-way clutch. Regarding the axial direction, in FIGS. 1 to 3, the front side of the paper surface is one side or the front side in the axial direction, and the back side of the paper surface is the other side in the axial direction. Regarding the circumferential direction, in FIGS. 1 to 3, the direction of rotation to the right toward the paper surface is defined as one side of the circumferential direction or the clockwise direction, and the direction of rotation to the left side of the paper surface is defined as the other side of the circumferential direction or the counterclockwise direction.

FIG. 1 is a front view showing a state in which a main part of the ratchet type one-way clutch 1 according to the embodiment is viewed from one side in the axial direction, and shows a non-meshing state between the claw member 3 and the tooth portion 5.
FIG. 2 is a front view showing a main part of the ratchet type one-way clutch 1 according to the embodiment, and shows only the outer ring 7 and the inner ring 9.
The ratchet type one-way clutch 1 according to the present embodiment has an annular shape as a whole when viewed from the axial direction, which is the same as the shape shown in FIG. 1 of Patent Document 1, and has a plurality of claw members 3 and a plurality of claw members 3. It is provided with a tooth portion 5. In FIG. 1, only one claw member 3 and one tooth portion 5, and a peripheral portion of these one claw member 3 and one tooth portion 5 are shown. The range shown in FIG. 2 and FIG. 3 described later is the same as that in FIG.

The ratchet type one-way clutch 1 according to the present embodiment has an annular outer ring 7, an annular inner ring 9 arranged coaxially with the outer ring 7 inward in the radial direction of the outer ring 7 and rotatably relative to the outer ring 7, and an outer ring 7. It has a ratchet mechanism that enables transmission of torque between the inner ring 9 and the inner ring 9.

On the outer peripheral surface of the inner ring 9, a large number of tooth portions 5 protruding outward in the radial direction and extending in the axial direction are formed at equal intervals in the circumferential direction. The tooth portion 5 has a substantially rectangular cross-sectional shape, and the top portion 6 of the tooth portion 5 is formed on a plane parallel to the axial direction or a curved surface slightly bulging outward in the radial direction. The tooth portion 5 extends from one end of the inner ring 9 in the axial direction to the other end.

A shaft hole (not shown) is formed in the central portion of the inner ring 9, and a drive shaft (not shown) such as an electric motor is fitted in the shaft hole.

A plurality of claw member holding portions 15 are formed on the inner peripheral portion of the outer ring 7 at equal intervals in the circumferential direction. The claw member holding portion 15 is a recess that opens inward in the radial direction. The claw member holding portion 15 penetrates the outer ring 7 in the axial direction. A first recess 17 and a second recess 21 are formed in each of the claw member holding portions 15 so as to be adjacent to each other in the circumferential direction. One claw member 3 is oscillatingly held in the first recess 17, and one coil-shaped spring 19 for urging the claw member 3 toward the inner ring 9 is arranged in the second recess 21. ing. In this way, one claw member holding portion 15 holds a set of the claw member 3 and the spring 19. The first recess 17 is recessed from the inner peripheral surface of the outer ring 7 toward one side in the circumferential direction and outward in the radial direction. The second recess 21 is recessed from the inner peripheral surface of the outer ring 7 toward the other side in the circumferential direction and outward in the radial direction. The ratchet mechanism is composed of the tooth portion 5 of the inner ring 9, the claw member holding portion 15, the claw member 3 held by the claw member holding portion 15, and the spring 19. In the present embodiment, the spring 19 is coiled, but the form of the spring is not limited to this.

A spline (not shown) is formed on the outer peripheral portion of the outer ring 7, and a shaft member connected to the spline is connected to a driven side device (not shown) to which a driving force such as an electric motor is transmitted. (Not shown) is fitted. Alternatively, the outer ring 7 can be fixed and the ratchet type one-way clutch 1 can be used as a backstop.

In the ratchet type one-way clutch 1 of the present embodiment, in FIG. 1, when the inner ring 9 rotates clockwise, the relative rotation of the inner ring 9 with respect to the outer ring 7 is fixed, and when the inner ring 9 rotates counterclockwise, the outer ring 7 is fixed. On the other hand, the inner ring 9 idles.

Specifically, when the inner ring 9 rotates clockwise, the plurality of claw members 3 of the outer ring 7 mesh with the tooth portions 5 of the inner ring 9, respectively. Specifically, the tip of the claw member 3 of the outer ring 7 meshes with the surface 23 on one side in the circumferential direction of the tooth portion 5 in the meshing between the claw member 3 and the tooth portion 5. As described above, the surface 23 on one side of the tooth portion 5 of the inner ring 9 in the circumferential direction constitutes the meshing surface of the tooth portion 5 that meshes with the claw member 3 of the outer ring 7. In the following description, the surface 23 of the tooth portion 5 is also referred to as "the meshing surface 23 of the tooth portion 5". When the claw member 3 and the tooth portion 5 mesh with each other, the outer ring 7 and the inner ring 9 rotate integrally, and torque is transmitted from the inner ring 9 to the outer ring 7. Alternatively, when the outer ring 7 is fixed, the rotation of the inner ring 9 with respect to the outer ring 7 is fixed, so that it functions as a backstop that prevents the inner ring 9 from rotating clockwise.

On the other hand, when the inner ring 9 rotates counterclockwise, the plurality of claw members 3 do not mesh with the tooth portions 5 of the inner ring 9, and the inner ring 9 idles with respect to the outer ring 7. In this state, torque is not transmitted from the inner ring 9 to the outer ring 7. In this way, the ratchet mechanism switches the inner ring 9 and the outer ring 7 between the torque transmission state and the torque non-transmission state.

The ratchet type one-way clutch 1 according to the present embodiment has a structure in which the spring 19 exhibits stable behavior when the inner ring 9 rotates counterclockwise and idles with respect to the outer ring 7. Hereinafter, the configuration of the ratchet mechanism of the ratchet type one-way clutch 1 according to the present embodiment will be described in more detail.

As shown in FIG. 2, the first recess 17 of the claw member holding portion 15 is continuous with the first accommodating portion 25 that opens to the inner ring 9 side and the first accommodating portion 25 that opens on the side opposite to the opening on the inner ring 9 side. It is composed of a second accommodating portion 27 formed in the above. The continuous portion between the first accommodating portion 25 and the second accommodating portion 27 has a radial width due to an outer diameter side projecting portion 29 projecting inward in the radial direction and an inner diameter side projecting portion 31 projecting outward in the radial direction. It is narrowly formed. The second accommodating portion 27 is formed on one side in the circumferential direction of the first accommodating portion 25 and on the outer diameter side of the first accommodating portion 25.

As shown in FIG. 2, the cross-sectional shape of the first accommodating portion 25 viewed from one side in the axial direction includes an arc-shaped portion 33 on the outer diameter side and an arc-shaped portion 35 on the inner diameter side. That is, the inner peripheral surface of the first accommodating portion 25 is a partial cylindrical inner peripheral surface 37 on the outer diameter side having an arc-shaped portion 33 on the outer diameter side as a cross section and an inner peripheral side having an arc-shaped portion 35 on the inner diameter side as a cross section. It is composed of a partial cylindrical inner peripheral surface 39. The inner peripheral surface 37 of the partial cylinder on the outer diameter side and the inner peripheral surface 39 of the partial cylinder on the inner diameter side extend in the axial direction. On the outer diameter side of the partial cylinder inner peripheral surface 37, one end in the circumferential direction is smoothly continuous with the outer diameter side protrusion 29, and the other end in the circumferential direction is smoothly continuous with the other side edge in the circumferential direction of the opening on the inner ring 9 side. are doing. The inner peripheral surface 39 of the partial cylinder on the inner diameter side has one end in the circumferential direction smoothly continuous with the one side edge in the circumferential direction of the opening on the inner ring 9 side, and the other end in the circumferential direction smoothly continuous with the protrusion 31 on the inner diameter side. There is.

As shown in FIG. 2, the cross-sectional shape of the second accommodating portion 27 viewed from one side in the axial direction has a substantially elliptical shape that is long in the substantially radial direction in which the continuous portion with the first accommodating portion 25 opens. In other words, the cross-sectional shape of the second accommodating portion 27 has a substantially C-shape that is long in the radial direction and the continuous portion with the first accommodating portion 25 opens. Therefore, the inner peripheral surface of the second accommodating portion 27 is a substantially C-shaped partial cylindrical inner peripheral surface extending in the axial direction with a long cross-sectional shape in the radial direction. One end of the inner peripheral surface of the second accommodating portion 27 in the circumferential direction is smoothly continuous with the inner diameter side protrusion 31, and the other end in the circumferential direction is smoothly continuous with the outer diameter side protrusion 29. The radius of curvature of the bottom surface 41 of the second accommodating portion 27, that is, the portion of the inner peripheral surface of the second accommodating portion 27 facing the opening on the first accommodating portion 25 side is within the partial cylinder on the outer diameter side of the first accommodating portion 25. It is formed larger than the radius of curvature of the peripheral surface 37 and the inner peripheral surface 39 of the partial cylinder on the inner diameter side. Since the first accommodating portion 25 and the second accommodating portion 27 have such a configuration, the cross-sectional shape of the first recess 17 viewed from one side in the axial direction is a continuous portion between the first accommodating portion 25 and the second accommodating portion 27. It has a gourd shape.

As shown in FIG. 1, the claw member 3 is composed of a main body portion 43 and a claw portion 45 projecting from the main body portion 43 to the other side in the circumferential direction. The main body portion 43 and the claw portion 45 are integrally formed. The outer shape of the main body 43 when viewed from one side in the axial direction is a gourd shape in which a constricted portion 47 having a smaller radial dimension is formed in the central portion. The main body 43 is composed of a swinging portion 49 on one side in the circumferential direction of the constricted portion 47 and a cylindrical portion 51 on the other side in the circumferential direction of the constricted portion 47, centering on the constricted portion 47. Therefore, the claw member 3 is composed of a cylindrical portion 51 at the center, a swinging portion 49 protruding from the cylindrical portion 51 in the circumferential direction, and a claw portion 45 protruding from the cylindrical portion 51 in the circumferential direction. There is. In the claw member 3, the cylindrical portion 51 is arranged in the first accommodating portion 25 of the claw member holding portion 15, the swinging portion 49 is arranged in the second accommodating portion 27 of the claw member holding portion 15, and the claw portion 45 is the first. It protrudes from the opening on the inner ring side of the accommodating portion 25 toward the other side in the circumferential direction and the inner ring 9 side. The constricted portion 47 of the claw member 3 is arranged so as to correspond to the outer diameter side protruding portion 29 and the inner diameter side protruding portion 31 of the claw member holding portion 15.

The cylindrical portion 51 of the claw member 3 is arranged in the first accommodating portion 25 of the claw member holding portion 15 in a direction in which the axial direction of the cylindrical portion 51 itself is parallel to the axial direction of the ratchet type one-way clutch 1. The claw member 3 is arranged in the first accommodating portion 25 so as to be swingable around the cylindrical portion 51. The cross-sectional shape of the cylindrical portion 51 viewed from one side in the axial direction has arc-shaped portions on the outer diameter side and the inner diameter side, respectively. That is, the cylindrical portion 51 has a partial cylindrical outer peripheral surface 53 on the outer diameter side having an arc-shaped portion on the outer diameter side as a cross section, and a partial cylindrical outer peripheral surface 55 on the inner diameter side having an arc-shaped portion on the inner diameter side as a cross section. ing. The radius of curvature of the outer diameter side partial cylinder outer peripheral surface 53 and the inner diameter side partial cylinder outer peripheral surface 55 is the outer diameter side partial cylinder inner peripheral surface 37 and the inner diameter side partial cylinder inner circumference of the first accommodating portion 25, respectively. It is formed in a size that matches the radius of curvature of the surface 39. When the claw member 3 swings, the outer diameter side partial cylinder outer peripheral surface 53 and the inner diameter side partial cylindrical outer peripheral surface 55 of the cylindrical portion 51 are respectively the outer diameter side partial cylindrical inner peripheral surface 37 of the first accommodating portion 25. And it slides smoothly with respect to the inner peripheral surface 39 of the partial cylinder on the inner diameter side.

The cross-sectional shape of the swinging portion 49 of the claw member 3 when viewed from one side in the axial direction is a substantially fan shape extending from the constricted portion 47 side to one side in the circumferential direction and outward in the radial direction, centering on the constricted portion 47 side. ing. The arcuate portion of the cross section of the rocking portion 49, that is, the bottom surface 57 of the rocking portion 49 is a curved surface or a partial cylindrical outer peripheral surface that bulges outward in the circumferential direction and outward in the radial direction. The radius of curvature of the bottom surface 57 of the swinging portion 49 is formed to have a size that matches the radius of curvature of the bottom surface 41 of the second accommodating portion 27. The inner diameter side end portion of the bottom surface 57 of the rocking portion 49 is continuous with the inner diameter side side surface of the rocking portion 49 via a smooth curved surface. The outer diameter side end portion of the bottom surface 57 of the rocking portion 49 is continuous with the outer diameter side side surface of the rocking portion 49 via a smooth curved surface. When the claw member 3 swings around the cylindrical portion 51, the swing portion 49 swings in the second accommodating portion 27 in the direction opposite to that of the claw portion 45.

The cross-sectional shape of the claw portion 45 of the claw member 3 when viewed from one side in the axial direction is a long rectangle in the circumferential direction. The side surface 59 on the outer diameter side of the claw portion 45 is formed in a plane parallel to the axial direction. The outer diameter side side surface 59 of the claw portion 45 is smoothly continuous with the outer diameter side partial cylindrical outer peripheral surface 53 of the cylindrical portion 51. The side surface 61 on the inner diameter side of the claw portion 45 is formed on a flat surface parallel to the axial direction or a curved surface slightly recessed outward in the radial direction. The side surface 61 on the inner diameter side of the claw portion 45 is smoothly continuous with the partial cylindrical outer peripheral surface 55 on the inner diameter side of the cylindrical portion 51. The end surface on the other side of the claw portion 45 in the circumferential direction, that is, the tip end surface of the claw portion 45 is the meshing surface on the claw member 3 side that meshes with the tooth portion 5.

The second recess 21 of the claw member holding portion 15 opens to the inner ring 9 side, and the edge portion on one side in the circumferential direction of the opening on the inner ring 9 side is the other side in the circumferential direction of the opening on the inner ring 9 side of the first accommodating portion 25. Smoothly continuous with the edge of the. The bottom surface 63 of the second recess 21 faces the side surface 59 on the outer diameter side of the claw portion 45 of the claw member 3 in the radial direction. A coiled spring 19 is arranged in the second recess 21. The spring 19 contacts the side surface 59 on the outer diameter side of the claw portion 45 of the claw member 3, and always urges the claw portion 45 inward in the radial direction.

In the ratchet type one-way clutch 1 of the present embodiment, the bottom surface 63 of the second recess 21 is formed in a plane parallel to the axial direction. The outer diameter side end 19a of the spring 19 is supported by the bottom surface 63 of the second recess 21. That is, the end portion 19a on the outer diameter side of the spring 19 is supported by the second recess 21 in a state of being in contact with the flat surface. Therefore, the spring 19 is supported perpendicularly to the bottom surface 63 of the second recess 21. Further, since the side surface 59 on the outer diameter side of the claw portion 45 is formed on a flat surface, the end portion 19b on the inner diameter side of the spring 19 urges the claw portion 45 inward in the radial direction in a state of being in contact with the flat surface. It will be. Therefore, the spring 19 is arranged between the bottom surface 63 of the second recess 21 and the outer diameter side side surface 59 of the claw portion 45 with both end portions 19a and 19b in contact with the flat surface, and both end portions 19a and 19b. Are all urging the claw portion 45 inward in the radial direction in a state of being in contact with a flat surface.

As described above, in the ratchet type one-way clutch 1 of the present embodiment, both ends 19a and 19b of the spring 19 are arranged between the second recess 21 and the claw portion 45 in a state where both ends 19a and 19b are in contact with a flat surface. Therefore, even if the claw portion 45 of the claw member 3 swings in the radial direction, it expands and contracts in a stable posture.

Further, the bottom surface 63 of the second recess 21 is formed so as to be able to take a position parallel to the side surface 59 on the outer diameter side of the claw portion 45 of the claw member 3 formed on a flat surface. Specifically, when the ratchet type one-way clutch 1 is idling, that is, when the inner ring 9 is rotating counterclockwise with respect to the outer ring 7, the top 6 of the tooth portion 5 is the claw portion of the claw member 3. When sliding on the inner diameter side side surface 61 of the 45, the bottom surface 63 of the second recess 21 becomes parallel to the outer diameter side side surface 59 of the claw portion 45.

When the top portion 6 of the tooth portion 5 slides on the side surface 61 on the inner diameter side of the claw portion 45 of the claw member 3, the claw portion 45 of the claw member 3 is located on the outermost diameter side. The spring 19 is in a state of being compressed by the bottom surface 63 of the second recess 21 and the side surface 59 on the outer diameter side of the claw portion 45. In this state, the ratchet type one-way clutch 1 of the present embodiment is configured such that the bottom surface 63 of the second recess 21 and the side surface 59 on the outer diameter side of the claw portion 45 are parallel to each other.

Next, the operation of the ratchet type one-way clutch 1 according to the present embodiment will be described. In the description of the operation of the ratchet type one-way clutch 1, for convenience, in the ratchet type one-way clutch 1, the outer ring 7 is fixed, the rotation of the inner ring 9 with respect to the outer ring 7 in one direction, that is, in the clockwise direction is locked, and the other direction, that is, Allows rotation in the counterclockwise direction.

A state in which the inner ring 9 rotates clockwise and the plurality of claw members 3 of the outer ring 7 mesh with the tooth portions 5 of the inner ring 9, specifically, the tip of the claw member 3 of the outer ring 7 is the circumference of the tooth portion 5. In the state of meshing with the surface 23 on one side in the direction, the rotation of the inner ring 9 with respect to the outer ring 7 is prevented. When the inner ring 9 rotates counterclockwise from this state, the plurality of claw members 3 are disengaged from the tooth portions 5 of the inner ring 9, and the inner ring 9 idles with respect to the outer ring 7. In this state, torque is not transmitted between the inner ring 9 and the outer ring 7.

When the inner ring 9 idles with respect to the outer ring 7, the tooth portion 5 of the inner ring 9 slides on the side surface 61 on the inner diameter side of the claw portion 45 of the claw member 3 from one side in the circumferential direction to the other side in the circumferential direction. As a result, in the claw member 3, the claw portion 45 swings outward in the radial direction with the cylindrical portion 51 as the center. Specifically, in a state where the tooth portion 5 is in contact with one end portion in the circumferential direction of the side surface 61 on the inner diameter side of the claw portion 45, the tip portion of the claw portion 45, that is, the other side in the circumferential direction of the side surface 61 on the inner diameter side. The end portion is in contact with the outer peripheral surface of the inner ring 9 of the portion between the tooth portions 5 adjacent to each other in the circumferential direction. In this state, the spring 19 urges the claw portion 45 toward the inner diameter side in the state where the total length is the longest.

From this state, when the tooth portion 5 moves to the other side in the circumferential direction due to the rotation of the inner ring 9, the top 6 of the tooth portion 5 moves on the side surface 61 on the inner diameter side of the claw portion 45 from one side in the circumferential direction to the other in the circumferential direction. Slide to the side. With this sliding of the tooth portion 5, the claw portion 45 swings outward in the radial direction. At this time, the swinging portion 49 of the claw member 3 swings in the second accommodating portion 27 in the direction opposite to that of the claw portion 45, that is, inward in the radial direction. In this state, the spring 19 has the shortest overall length, that is, the most compressed state. Further, in this state, the bottom surface 63 of the second recess 21 and the side surface 59 on the outer diameter side of the claw portion 45 are parallel to each other.

After that, when the tooth portion 5 reaches the other side end portion in the circumferential direction of the side surface 61 on the inner diameter side of the claw portion 45 and the tooth portion 5 further moves to the other side in the circumferential direction, the tip portion of the claw portion 45 becomes the tooth portion 5. The meshing surface 23 slides in the inner diameter direction, and the claw portion 45 swings inward in the radial direction. Then, the tip end portion of the claw portion 45 comes into contact with the outer peripheral surface of the inner ring 9 of the portion between the tooth portions 5 adjacent to each other in the circumferential direction again. At this time, the spring 19 is in the state where the total length is the longest again. In this state, the side surface 59 on the outer diameter side of the claw portion 45 has a radial distance from the bottom surface 63 of the second recess 21 with respect to the bottom surface 63 of the second recess 21 toward the other in the circumferential direction. Is slightly tilted in the direction of increasing.

In this way, when the inner ring 9 rotates counterclockwise with respect to the outer ring 7, the spring 19 repeats expansion and contraction as the claw member 3 swings, specifically, the claw portion 45 swings in the radial direction. In the ratchet type one-way clutch 1 of the present embodiment, the spring 19 repeats expansion and contraction in a state where both ends 19a and 19b are in contact with a flat surface. Therefore, the spring 19 repeats expansion and contraction in a stable posture. Further, in the ratchet type one-way clutch 1 of the present embodiment, when the total length of the spring 19 is the shortest, that is, the most compressed state, the bottom surface 63 of the second recess 21 and the outer diameter side surface of the claw portion 45 It becomes parallel to 59. That is, when a force in the most compressive direction is applied to the spring 19, both ends 19a and 19b of the spring 19 are claws with the bottom surface 63 of the second recess 21 which is a plane facing and parallel to the radial direction. It is held between the bottom surface 63 of the second recess 21 and the side surface 59 on the outer diameter side of the claw portion 45 in a state of being in contact with the side surface 59 on the outer diameter side of the portion 45, respectively. Therefore, the spring 19 can maintain a stable posture even in the most compressed state.

As described above, in the ratchet type one-way clutch 1 of the present embodiment, the spring 19 is in a state where the claw member 3 and the tooth portion 5 of the inner ring 9 are disengaged and the inner ring 9 is idling with respect to the outer ring 7. Maintain a stable posture and repeat expansion and contraction. As a result, the fatigue life of the spring 19 due to repeated expansion and contraction, that is, the durability can be improved. Further, since the spring 19 urges the claw member 3 against the inner ring 9 in a stable posture, the meshing behavior of the claw member 3 and the tooth portion 5 can be stabilized.

Further, in the ratchet type one-way clutch 1 of the present embodiment, since the end portion 19a of the spring 19 is supported on the bottom surface 63 of the second concave portion 21 which is a flat surface, a component for stabilizing the posture of the spring 19 is used. There is no need. As a result, a complicated mounting structure for mounting the spring 19 is not required, an increase in the number of parts can be suppressed, and the assembling property can be further improved.

Next, a ratchet type one-way clutch according to a comparative example will be described for comparison with the above embodiment.
FIG. 3 is a front view showing a main part of the ratchet type one-way clutch 101 according to the comparative example. The configuration of the ratchet type one-way clutch 101 shown in FIG. 3 will be described by adding a reference code obtained by adding 100 to the reference code of the above embodiment for the same configuration as that of the above embodiment.

The ratchet type one-way clutch 101 according to the comparative example is different from the ratchet type one-way clutch 1 according to the above embodiment in the configuration of the bottom surface 163 of the second recess 121 of the claw member holding portion 115. Specifically, in a state where the ratchet type one-way clutch 101 is idling, that is, a state in which the inner ring 109 is rotating counterclockwise with respect to the outer ring 107, the top 106 of the tooth portion 105 is the claw portion 145 of the claw member 103. When sliding on the inner diameter side side surface 161 of the second recess 121, the bottom surface 163 of the second recess 121 is not parallel to the outer diameter side side surface 159 of the claw portion 145. In this state, as shown in FIG. 3, the bottom surface 163 of the second recess 121 has a side surface on the outer diameter side of the claw portion 145 with respect to the side surface 159 on the outer diameter side of the claw portion 145 toward the other side in the circumferential direction. It is slightly tilted in the direction in which the radial distance from 159 becomes smaller. Other configurations are the same as those in the above embodiment.

As described above, in the ratchet type one-way clutch 101 according to the comparative example, when the total length of the spring 119 is the shortest, that is, the most compressed state, both ends 119a and 119b of the spring 119 are non-parallel planes. It is held between the bottom surface 163 of the second recess 121 and the outer diameter side side surface 159 of the claw portion 145 in a state of being in contact with the bottom surface 163 of the recess 121 and the outer diameter side side surface 159 of the claw portion 145. To. As a result, as shown in FIG. 3, the spring 119 is held in an unstable state in which the central portion is bent and tilted in the most compressed state. Therefore, in the ratchet type one-way clutch 101 according to the comparative example, the spring 119 repeatedly expands and contracts in an unstable posture. As a result, the fatigue life of the spring 119, that is, the durability may be lowered due to repeated expansion and contraction.

On the other hand, in the ratchet type one-way clutch 1 according to the embodiment, as described above, the spring 19 maintains a stable posture and repeats expansion and contraction, so that the durability of the spring 19 can be improved.

Further, when the spring 119 is held in an inclined state as in the ratchet type one-way clutch 101 of the comparative example, specifications such as the size and load of the spring 119 are limited, and as a result, the entire ratchet type one-way clutch There are some restrictions in the design. On the other hand, the ratchet type one-way clutch 1 according to the embodiment can stably hold the posture of the spring 19, so that the degree of freedom in design can be increased as compared with the conventional case.

The ratchet type one-way clutch 1 according to the embodiment is not limited to the above embodiment and can be changed as appropriate. For example, the tooth portion 5 may be formed on the inner peripheral surface of the outer ring 7, and the claw member 3 may be arranged on the inner ring 9. Further, the number and size of the claw members 3 can be appropriately designed according to the torque capacity transmitted between the inner and outer rings.

1 Ratchet type one-way clutch 3 Claw member 5 Tooth part 7 Outer ring 9 Inner ring 15 Claw member holding part 17 First recess 19 Spring 21 Second recess 23 Engaging surface 25 First accommodating portion 27 Second accommodating portion 41 Second accommodating portion Bottom surface 43 Main body 45 Claw 49 Shaking 51 Cylindrical 57 Bottom of swing 59 Side of the outer diameter side of the claw 61 Side of the inner diameter of the claw 63 Bottom of the second recess

Claims (3)

With the outer ring
An inner ring arranged coaxially with the outer ring and relatively rotatable inside the outer ring in the radial direction.
It has a ratchet mechanism capable of switching between the outer ring and the inner ring in a torque transmission state and a torque non-transmission state.
The ratchet mechanism includes a plurality of claw members provided on the inner peripheral portion of the outer ring and arranged so as to be swingable in the radial direction, and a plurality of claw members formed on the inner peripheral portion of the outer ring and opening inward in the radial direction. In a ratchet type one-way clutch, each of which is arranged in a recess and has a plurality of springs that come into contact with the outer diameter side surfaces of the plurality of claw members and urge the plurality of claw members toward the inner ring, respectively.
The bottom surface of the recess is formed flat, and the outer diameter side surface of the claw member is formed flat.
A ratchet type one-way clutch characterized in that the bottom surface of the recess and the surface on the outer diameter side of the claw member are parallel to each other when the outer ring and the inner ring are in the torque non-transmission state. On the outer peripheral portion of the inner ring, a plurality of tooth portions that mesh with the plurality of claw members and project outward in the radial direction are formed.
The ratchet according to claim 1, wherein the bottom surface of the recess and the outer diameter side surface of the claw member are parallel to each other when the tooth portion slides on the inner diameter side surface of the claw member. Type one-way clutch. The ratchet type one-way clutch according to claim 2, wherein the bottom surface of the recess and the outer diameter side surface of the claw member are parallel to each other when the claw member swings outward in the radial direction.

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