WO2023276409A1

WO2023276409A1 - Cam clutch

Info

Publication number: WO2023276409A1
Application number: PCT/JP2022/017675
Authority: WO
Inventors: 栄一中川; 幸平國松; 孝之森本
Original assignee: 株式会社椿本チエイン
Priority date: 2021-06-29
Filing date: 2022-04-13
Publication date: 2023-01-05
Also published as: JP2023005554A; JP7227515B2

Abstract

[Problem] To provide a cam clutch that can switch the operation mode without increasing complexity of a structure thereof even when both of an inner ring and an outer ring are used as rotary bodies. [Solution] The present invention comprises an operation mode switching mechanism (180) that switches the state between a free state for permitting relative rotary motions of an inner ring (110) and an outer ring (120) and a locked state for inhibiting the relative rotary motions. The operation mode switching mechanism (180) comprises cam attitude changing portions (185) which are provided so as to be operationally associated with the rotation of a plurality of cams (140) and independently rotatable and which forcibly change the attitudes of the cams by being brought into contact with the cams when being out of phase with the rotation of the plurality of cams (140).

Description

cam clutch

The present invention relates to a cam clutch that can be switched between a free state that permits relative rotational movement between the outer ring and the inner ring and a locked state that prohibits relative rotational movement between the outer ring and the inner ring.

A two-way clutch capable of switching between driving and idling in both forward and reverse directions is known as a clutch that controls transmission and cutoff of rotational force.
A type of two-way clutch has a locked state that prohibits relative rotational movement between the inner and outer rings (transmits rotational force) and permits relative rotational movement between the inner and outer rings (blocks rotational force). Switching to the free state is performed by tilting a cam or a sprag (see, for example, Patent Documents 1 and 2).

Further, in Patent Document 3, a retainer that holds both a first sprag and a second sprag biased by biasing means so that the rotation lock direction is reversed is controlled to It is possible to switch between three operation modes: a bidirectional free mode that allows rotation in both directions, a unidirectional lock mode that allows rotation only in the forward direction, and a unidirectional lock mode that allows rotation only in the reverse direction. A clutch is described which is constructed in

JP 2011-220509 A JP-A-11-182589 Japanese Unexamined Patent Application Publication No. 2011-231828 JP 2020-190255 A

Therefore, in the two-way clutch disclosed in Patent Document 1, when the input-side rotor rotates relative to the output-side rotor, the sprags tilt in the same direction as the rotation direction of the input-side rotor. Engagement and disengagement between the input-side rotating body and the output-side rotating body are switched. Therefore, there is a problem that time loss occurs when the rotation direction is switched, resulting in poor responsiveness. Also, the two-way clutch described in Patent Document 2 has the same problem.
The two-way clutch described in Patent Document 3 uses a leaf spring-like member to enable simultaneous power transmission in both directions. However, because power is transmitted by friction, there is a problem that the torque that can be transmitted to the size of the two-way clutch is small.

The purpose of the present application is to provide a cam clutch that solves such problems, has a simple structure, can switch operation modes, has high responsiveness, and can secure a desired torque capacity. A person invented a cam clutch having an operation mode switching mechanism shown in Patent Document 4.
In the first, second, and fourth embodiments of the cam clutch described in Patent Document 4, when the outer ring is used as a rotating body, a complicated mechanism is required to operate the operation mode switching mechanism from the stationary side. There was a problem.
Moreover, in the third embodiment, there is a problem that a cam of a special shape is required and the size in the axial direction becomes large.

SUMMARY OF THE INVENTION It is an object of the present invention to solve these problems and to provide a cam clutch capable of switching the operation mode without complicating the structure even if both the inner ring and the outer ring are used as rotating bodies. do.

The present invention is a cam clutch comprising an inner ring and an outer ring which are coaxially provided so as to be relatively rotatable, and a plurality of cams arranged at intervals in the circumferential direction between the inner ring and the outer ring, An operation mode switching means provided so as to be rotatable independently of and interlocked with the rotation of the plurality of cams rotating together with the inner ring or the outer ring, wherein the operation mode switching means has a cam attitude changing section, The cam attitude changing section is configured to contact the cams and forcibly change the attitudes of the cams when the operation mode switching means is controlled in rotation and is out of phase with the rotation of the plurality of cams. This solves the above problems.

According to the first aspect of the invention, by controlling the rotation of the operation mode switching means from the outside, the attitude of the cam can be forcibly changed to change the operation mode. Even if it is used with a body, the operation mode can be switched without complicating the structure.

According to the second aspect of the present invention, the circumferential position of the cam and the posture of the cam can be more reliably regulated, and the operation mode can be reliably switched by the operation mode switching means.
According to the configuration of claim 3, the rotation of the operation mode switching means can be reliably stopped from the outside, and the operation mode can be quickly switched.

According to the configuration of claim 4, any torque can be applied to the operation mode switching means to control the rotation, and the impact at the time of switching the operation mode can be alleviated.
According to the fifth aspect of the invention, the operation mode can be switched for rotation in both directions.

1 is a perspective view of a cam clutch according to a first embodiment of the invention; FIG. FIG. 2 is a perspective view of the cam clutch shown in FIG. 1 as seen from another angle; FIG. 2 is a cross-sectional perspective view of the cam clutch shown in FIG. 1 cut along a plane including the rotational axis; FIG. 2 is a cross-sectional view taken along a plane including the rotational axis of the cam clutch shown in FIG. 1; 2 is a cross-sectional view taken along a plane perpendicular to the rotational axis of the cam clutch shown in FIG. 1; FIG. 2 is a cross-sectional perspective view taken along a plane perpendicular to the rotational axis of the cam clutch shown in FIG. 1; FIG. 2 is a perspective view of operation mode switching means of the cam clutch shown in FIG. 1; FIG. FIG. 2 is a perspective view of a cam cage and cams in the cam clutch shown in FIG. 1; FIG. 5 is a perspective view of a cam clutch according to a second embodiment of the invention; FIG. 10 is a perspective view of operation mode switching means of the cam clutch shown in FIG. 9; FIG. 4 is an explanatory diagram of the operation of the cam clutch of the present invention; FIG. 5 is a simplified explanatory diagram of a modification of the cam clutch of the present invention;

An embodiment of the present invention will be described with reference to FIGS. 1 to 8. FIG. However, the present invention is not limited to these embodiments.

The cam clutch 100 according to the first embodiment of the present invention, as shown in FIGS. and a cam mechanism 130 for transmitting and interrupting power between them.
The cam mechanism 130 includes a plurality of cams 140 arranged between the inner ring 110 and the outer ring 120, a cam cage 150 that holds each of the plurality of cams 140 on the same circumference at predetermined intervals in the circumferential direction, and a plurality of It is composed of an annular garter spring 135 which is a biasing means for biasing each of the cams 140 to come into contact with the inner ring 110 and the outer ring 120 .

The cams 140 are held by the cam cage 150 by attaching the garter springs 135, the positions of the cams 140 in the circumferential direction are restricted, and the attitudes of the cams 140 are restricted, so that the attitudes (inclinations) of all the cams 140 vary. contact with the inner ring 110 and the outer ring 120 without causing
The cam clutch 100 is provided with a cage detent 170 that is fixed to the outer ring 120 and prohibits relative rotation of the cam cage 150 with respect to the outer ring 120 .
In this embodiment, the cams 140 that operate in different rotational directions are alternately provided, and when the cams 140 are operable, relative rotational movement of the inner ring 110 and the outer ring 120 in both directions is prohibited.

The cam clutch 100 according to the present embodiment switches between a free state in which relative rotational movement between the inner ring 110 and the outer ring 120 is permitted and a locked state in which relative rotational movement between the inner ring 110 and the outer ring 120 is prohibited. A mode switching means 180 is provided.
The operation mode switching means 180 of this embodiment includes an annular main body portion 181, a plurality of strip members 185 provided to extend axially from the inner peripheral edge of one surface of the main body portion 181 and functioning as cam posture changing portions, and a peripheral wall portion 182 extending from the body portion 181 toward the outer peripheral side of the outer ring 120 .
The operation mode switching means 180 has a peripheral wall portion 182 fitted on the cage detent 170 via a cylindrical concentric holding member 190, and a plurality of strip-like members 185 between the cams 140 adjacent to each other. located close to.

The concentric holding member 190 aligns the rotation axis of the operation mode switching means 180 with the rotation axes of the inner ring 110 and the outer ring 120, and the operation mode switching means 180 can interlock with the rotation of the plurality of cams 140 that rotate together with the outer ring 120. Any member such as a bearing member, an elastic member, or a lubricating sheet may be used as long as it can rotate independently.
Alternatively, the concentric holding member 190 may be omitted, and the peripheral wall portion 182 of the operation mode switching means 180 may be directly rotatably fitted around the cage detent 170 or the outer circumference of the outer ring 120 .
A concave portion 183 is provided on the outer peripheral edge of the main body portion 181 , and by inserting a convex portion into the concave portion 183 from the outside, it is possible to prevent the operation mode switching means 180 from rotating.

FIG. 9 is a perspective view of a cam clutch according to a second embodiment of the invention.
As shown in FIGS. 9 and 10, this cam clutch has a gear 184 formed on the outer peripheral edge of a body portion 181. The gear 184 has an engaging gear G provided on the rotating shaft of the braking portion S. By engaging and controlling the rotational resistance of the braking portion S, the rotation of the operation mode switching means 180 can be prevented.
Other configurations are the same as those of the first embodiment.
As a result, the rotation resistance of the braking portion S is set to zero, thereby entering a lock mode in which relative rotation of the inner ring 110 and the outer ring 120 in the normal and reverse directions is prohibited. , a bidirectional free mode in which relative rotation of the inner ring 110 and the outer ring 120 in the forward and reverse directions is permitted.
According to this configuration, even if the rotation of the operation mode switching means 180 is restricted while the outer ring 120 is rotating, the operation mode switching means 180 and the outer ring 120 do not suddenly stop rotating, and the mode is shifted to the bidirectional free mode. becomes possible.

Next, the operation of cam clutch 100 will be described.
The cam clutch 100 is in a lock mode in which relative rotation of the inner ring 110 and the outer ring 120 in forward and reverse directions is prohibited when the plate member 185 that constitutes the cam posture changing portion is in the neutral position. By restricting the rotation of the mode switching means 180, the operation mode of the cam clutch 100 can be switched from the bi-directional lock mode to the bi-directional free mode in which relative forward and reverse rotation of the inner ring 110 and the outer ring 120 is allowed. can be done.
That is, in a state in which the operation mode switching means 180 can rotate freely without inserting a protrusion from the outside into the recess 183, the operation mode switching means 180 rotates together with the outer ring 120 and the cam cage 150 with almost no resistance. The strip member 185 does not change the attitude of the cam 140 regardless of which direction 120 rotates.
Therefore, the cam 140 operates to transmit torque to the relative rotation of the inner ring 110 and the outer ring 120, and a lock mode is established in which the relative rotation of the inner ring 110 and the outer ring 120 in the normal and reverse directions is prohibited. .

When the rotation of the operation mode switching means 180 is restricted by inserting a projection into the recess 183 from the outside, applying a rotational resistance of the braking portion S, or the like, the operation mode switching means 180 moves relative to the rotation of the outer ring 120. Because of the rotation, the cam 140 rotating together with the outer ring 120 and the strip member 185 rotate relatively, and the strip member 185 comes into contact with the inner ring 110 side of the cam 140 to change the posture of the cam 140. Release 140 contact.
As a result, transmission of torque between inner ring 110 and outer ring 120 by cam 140 is cut off, and relative rotation of inner ring 110 and outer ring 120 is permitted.
In this embodiment, since the cams 140 that operate in different rotational directions are alternately provided, the same effect occurs in both the forward and reverse directions of relative rotation of the inner ring 110 and the outer ring 120, resulting in rotation in both directions. is a bidirectional free mode that allows

For example, the operation in the case of shifting from a state in which torque is transmitted to the outer ring 120 by rotating the inner ring 110 clockwise in the lock mode to the bidirectional free mode will be described with reference to FIG. 11 .
In the lock mode, as shown in a, the inner ring 110 is rotating as indicated by the black arrow, the left cam 140 comes into contact with the inner ring 110 and the outer ring 120 and torque is transmitted to the outer ring 120, while the outer ring 120 is white. While rotating at the same speed as the inner ring 110 as indicated by the arrow, the operation mode switching means 180 also rotates at the same speed as the outer ring 120 as indicated by the white arrow.
As a result, the strip member 185 is held at a position that does not affect the posture of the cam 140 at all.

When the rotation of the operation mode switching means 180 is braked in order to shift to the bidirectional free mode, the rotational speed of the operation mode switching means 180 becomes lower than that of the outer ring 120, as shown in b, so that the leaf-like member 185 moves to the outer ring. The cam 140 rotating at the same speed as 120 is approached.
Then, as shown in c, the tab-like member 185 lifts the inner ring 110 side of the cam 140 to cut off torque transmission between the inner ring 110 and the outer ring 120 by the cam 140, and the inner ring 110 continues to rotate freely. The outer ring 120 and the operation mode switching means 180 are stopped.
When the inner ring 110 rotates in the reverse direction, the cam on the right side of the drawing has the same action, and is free in both directions.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and the shape and arrangement of each component, the presence or absence of other accessory mechanisms, etc., do not depart from the scope of the present invention. Various design modifications are possible.
In the above embodiment, the cam cage rotates together with the outer ring and the operation mode switching means rotates together with the outer ring. However, the cam cage rotates together with the inner race and the operation mode switching means rotates together with the inner ring. may
Also, the cam mechanism may be one that transmits torque only in one of the forward rotation direction and the reverse rotation direction (a so-called one-way clutch), and a plurality of cam mechanisms may be arranged in parallel in the axial direction.
Also, the cam cage and the cage detent may be integrally formed.
The means for controlling the rotation of the operation mode switching means 180 may be any means, such as a friction clutch, as long as the plate-shaped member 185 can provide rotational resistance at a level that changes the posture of the cam 140. may
Further, according to the torque transmission path, the rotation mode of the cam cage, the shape of the cam, etc., as shown in FIG. Alternatively, as shown in FIG. 12b, both the tab member 185 contacting the outer ring 120 side and the inner ring 110 side of the cam 140 may be arranged.

100... Cam clutch 110... Inner ring 120... Outer ring 130... Cam mechanism 135... Garter spring 140... Cam 150... Cam cage 170... Cage detent 180... Operation Mode switching means 181 Main body portion 182 Peripheral wall portion 183 Recessed portion 184 Gear 185 Piece member (cam position changing portion)
190... Concentric holding member S... Braking part G... Engagement gear

Claims

A cam clutch comprising an inner ring and an outer ring coaxially provided so as to be relatively rotatable, and a plurality of cams circumferentially spaced between the inner ring and the outer ring,
An operation mode switching means provided so as to be rotatable independently and interlockable with the rotation of the plurality of cams rotating together with the inner ring or the outer ring,
The operation mode switching means has a cam attitude changing section,
The cam attitude changing section is configured to contact the cams and forcibly change the attitudes of the cams when the operation mode switching means is controlled in rotation and is out of phase with the rotation of the plurality of cams. A cam clutch characterized by:
the plurality of cams are restricted in circumferential position by a cam cage that rotates together with the inner ring or the outer ring;
2. A cam clutch according to claim 1, wherein said operation mode switching means is provided so as to be rotatable independently of and interlocked with rotation of said cam cage.
3. The cam according to claim 2, wherein the operation mode switching means is provided with a concave portion on the outer periphery thereof, and is configured such that rotation is restricted by inserting a convex portion into the concave portion from the outside. clutch.
3. The cam according to claim 2, wherein the operation mode switching means is provided with a gear on its outer circumference, and is configured to restrict rotation by applying a rotational load by meshing with the gear from the outside. clutch.
the plurality of cams includes a first cam and a second cam to which moments in different directions are applied by the biasing means;
5. The cam clutch according to any one of claims 1 to 4, wherein said operation mode switching means is configured to be able to change the attitude of said first cam and the attitude of said second cam. .