Cam clutch

Abstract

To provide a cam clutch easily switchable from a torque transmitting state to a freewheeling state even during torque transmission between raceway members.SOLUTION: A cam clutch 10 includes a plurality of cams 41 disposed between a first raceway member 21 and a second raceway member 31. The first raceway member 21 and second raceway member 31 are spaced in an axial direction X along the rotation axis of the first raceway member 21. The cams 41 are disposed between the first raceway member 21 and the second raceway member 31 in the axial direction X, and the first raceway member 21 and the second raceway member 31 can relatively move toward and away from each other in the axial direction X.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a cam clutch. [Background technology]

[0002] Conventionally, there has been known a cam clutch that includes a rotatably mounted first raceway member, a second raceway member that is rotatably mounted coaxially with the first raceway member, and a number of cams disposed between the first raceway member and the second raceway member, and that is configured to transmit torque between the first raceway member and the second raceway member via the cams when the first raceway member and the second raceway member are rotated relative to one another (see, for example, Patent Document 1).

[0003] In the cam clutch disclosed in Patent Document 1, one raceway member (outer ring) is arranged radially inside the other raceway member (inner ring), and multiple cams are arranged radially between the one raceway member (outer ring) and the other raceway member (inner ring), and is configured to transmit torque between the first raceway member and the second raceway member by changing the radial height of each cam during relative rotation between the first raceway member and the second raceway member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-190255 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the cam clutch according to Patent Document 1 has a problem in that it is difficult to switch to an idling state in which no torque is transmitted between the first and second raceway members while torque is being transmitted between the first and second raceway members. That is, in the cam clutch according to Patent Document 1, in a torque transmission state in which torque is transmitted between the first and second raceway members, each cam is in strong radial contact with each raceway member, and a large frictional force acts between each raceway member and each cam, making it difficult to switch to an idling state.

[0006] Therefore, the present invention is intended to solve these problems and has an object to provide a cam clutch that has a simple configuration and can be easily switched from a torque transmission state to a free-spinning state even while torque is being transmitted between track members. [Means for solving the problem]

[0007] The present invention relates to a cam clutch including a rotatably installed first raceway member, a second raceway member installed rotatably about the same axis as the first raceway member, and a plurality of cams arranged between the first raceway member and the second raceway member, the first raceway member and the second raceway member being arranged apart from each other in an axial direction along a rotation axis of the first raceway member, the plurality of cams being arranged between the first raceway member and the second raceway member in the axial direction, and the first raceway member and the second raceway member being arranged so as to be relatively movable toward and away from each other in the axial direction. the first raceway member has a first raceway surface formed in an annular shape around the rotation axis of the first raceway member on a side facing the second raceway member, the second raceway member has a second raceway surface formed in an annular shape around the rotation axis of the second raceway member on a side facing the first raceway member, and the plurality of cams are arranged in an annular shape around the rotation axis of the first raceway member between the annular first raceway surface and the annular second raceway surface in the axial direction. By doing so, the above-mentioned problems are solved. Effect of the Invention

[0008] Claims 1-2 According to the present invention, the first raceway member and the second raceway member are disposed apart from each other in an axial direction along the rotation axis of the first raceway member, a plurality of cams are disposed between the first raceway member and the second raceway member in the axial direction, and the first raceway member and the second raceway member are provided so as to be movable relatively close to each other and apart from each other in the axial direction. The first raceway member has a first raceway surface formed in an annular shape around the rotation axis of the first raceway member on a side facing the second raceway member, and the second raceway member has a second raceway surface formed in an annular shape around the rotation axis of the second raceway member on a side facing the first raceway member, and the multiple cams are arranged in an annular shape around the rotation axis of the first raceway member between the annular first raceway surface and the annular second raceway surface in the axial direction.As a result, even when the cam is in contact with both the first and second raceway members to transmit torque between the raceway members, the first and second raceway members can be relatively separated in the axial direction without any hindrance. Therefore, with this simple configuration, the torque transmission state can be easily switched to the idling state even when torque is being transmitted between the raceway members.

[0009] Claim 3 According to the invention, a cam cage capable of holding multiple cams is biased toward the first track member, and each cam is maintained in contact with the first track member, thereby making it possible to effectively control the posture of each cam by contact with the first track member. Claim 4 According to the invention, the cam holding portion of the cam cage that holds the cam is formed to receive the cam from the first track member side of the cam cage in the axial direction, thereby simplifying the structure of the cam holding portion of the cam cage while reliably preventing each cam from falling off from the cam cage due to contact with the first track member. Claim 5 According to the invention, when the second locking engagement portion engages with the first locking engagement portion, the second track member is prevented from separating from the first track member in the axial direction, and at least one of the first locking engagement portion or the second locking engagement portion is provided movable in a radial direction perpendicular to the axial direction. Therefore, the first locking engagement portion and the second locking engagement portion can be automatically and releasably engaged by an action of bringing the second track member unit closer to the first track member unit in the axial direction. Claim 6 According to the invention, the elastic member of the second track member unit has a portion that moves radially when elastically deformed, and the radially moving portion functions as the second locking engagement portion, so that the first locking engagement portion and the second locking engagement portion can be smoothly engaged by the action of bringing the track member units closer to each other in the axial direction. Claim 7According to the invention, the control spring of the second track member unit has a first annular portion and a second annular portion arranged axially apart, and a plurality of bent pieces arranged side by side in the circumferential direction and axially connecting the first annular portion and the second annular portion, and is formed so that each bent piece moves radially upon elastic deformation. By having each bent piece function as a second locking engagement portion, the structure of the locking mechanism is simplified, while the first locking engagement portion and the second locking engagement portion can be smoothly engaged by the action of bringing the track member units closer to each other in the axial direction. Claim 8 According to the invention, by providing a biasing means between the second track member, which contacts the multiple cams, and the control member, which engages with the first locking engagement portion of the first track member unit, for biasing the second track member and the control member so as to move them away from each other, the second track member can be brought into stable and even contact with the multiple cams. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a perspective view showing a cam clutch according to an embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. 4 is an exploded sectional perspective view of the cam clutch; [Figure 4] FIG. 4 is an exploded sectional perspective view of the second track member unit. [Diagram 5] FIG. 4 is an exploded sectional perspective view of the cam unit. [Figure 6] FIG. 11 is a cross-sectional view showing a state in which a second raceway member is in contact with the cam. [Figure 7] FIG. 11 is a cross-sectional view showing a state in which the second raceway member is separated from the cam. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cam clutch 10 according to an embodiment of the present invention will now be described with reference to the drawings.

[0012] The cam clutch 10 is incorporated in an automobile or the like, and as shown in Figures 1 and 2, comprises a rotatably installed first raceway member 21, a second raceway member 31 rotatably installed around the same axis as the first raceway member 21, and a plurality of cams 41 disposed between the first raceway member 21 and the second raceway member 31, and transmits the torque of an input shaft (not shown) connected (directly or indirectly) to one of the first raceway member 21 or the second raceway member 31 to an output shaft (not shown) connected (directly or indirectly) to the other of the first raceway member 21 or the second raceway member 31. Each component of the cam clutch 10 is formed from metal or the like.

[0013] Each component of the cam clutch 10 will be described below.

[0014] First, as shown in FIG. 2, the cam clutch 10 includes a first track member unit 20 having a first track member 21, a second track member unit 30 having a second track member 31, and a cam unit 40 having a cam 41.

[0015] As shown in FIGS. 2 and 3, the first raceway member unit 20 includes an annular first raceway member 21 and a cylindrical casing 22 fixed to the first raceway member 21.

[0016] As shown in Figures 2 and 3, the first track member 21 is formed in a disk shape having a through hole at the center that penetrates in the axial direction X along the rotation axis of the first track member 21 (and the second track member 31). 3 and 6, the first track member 21 has a first track surface 21a disposed opposite the cam 41 in the axial direction X on the side opposite the second track member 31. The first track surface 21a is formed in the shape of an annular flat surface centered on the rotation axis of the first track member 21.

[0017] The casing 22 is formed in a tubular (cylindrical) shape and, as shown in FIG. 3, has on its inner circumferential wall, in order from the first track member 21 side (in order from the upper side in FIG. 3), an annular track member recess 22a for installing the first track member 21, an annular cam recess 22b for disposing a cam cage 42 described later, a spring recess 22c for disposing a control spring 33 described later, and an annular, convex first lock engagement portion 22d for engaging with a second lock engagement portion 33d of the control spring 33.

[0018] The above-mentioned input shaft (not shown) or output shaft (not shown) is connected to at least one of the first raceway member 21 and the casing 22, and is connected to the first raceway member 21 in this embodiment.

[0019] As shown in Figures 3 and 4, the second track member unit 30 includes an annular second track member 31 arranged away from the first track member 21 in the axial direction X, a control member 32 arranged on the rear side (the lower side in Figures 3 and 4) opposite to the front side facing the first track member 21 in the axial direction X, an annular control spring 33 as a control elastic member 33 arranged on the outer periphery of the control member 32, a bolt 34 for attaching the second track member 31 to the control member 32, a biasing spring 35 (shown in Figures 6 and 7) arranged between the second track member 31 and the control member 32, and an annular selector member 36 arranged on the outer periphery of the control member 32.

[0020] As can be seen from FIGS. 6 and 7, the entire second track member unit 30 including the second track member 31 is provided so as to be movable toward and away from the first track member unit 20 including the first track member 21 in the axial direction X.

[0021] As shown in Figs. 3 and 4, the second raceway member 31 is formed in a disk shape having a through hole penetrating in the axial direction X at the center. As shown in Figures 3 and 4, the second track member 31 is attached to the control member 32 by a bolt 34 in a manner that allows the second track member 31 to move in the axial direction X by a predetermined distance relative to the control member 32 and does not rotate relative to the control member 32. Specifically, as shown in Figure 4, the bolt 34 is inserted into a bolt hole formed in the second track member 31 with some play, and its bolt shank is fixed to the control member 32 and its bolt head is disposed on the first track member 21 side of the second track member 31. This prevents the second track member 31 from rotating relative to the control member 32, and the movement of the second track member 31 toward the first track member 21 side relative to the control member 32 in the axial direction X is restricted to a predetermined distance by the bolt head of the bolt 34. 3 and 4, the second track member 31 has an annular protrusion 31b protruding toward the control member 32, and this annular protrusion 31b is disposed in a track member recess 32a formed in the control member 32. This restricts radial movement of the second track member 31 relative to the control member 32. 3 and 4, the second track member 31 has a second track surface 31a disposed opposite the cam 41 in the axial direction X on the side facing the first track member 21. The second track surface 31a is formed in the shape of an annular flat surface centered on the rotation axis of the second track member 31 (first track member 21). As shown in FIG. 2, the inner peripheral surface of the second raceway member 31 is formed with a key groove 31c for engaging with the key of the input shaft (not shown) or the output shaft (not shown).

[0022] As shown in Figs. 3 and 4, the control member 32 is formed in a tubular (approximately cylindrical) shape having a through hole penetrating in the axial direction X at the center. As shown in FIG. 3 and FIG. 4, the control member 32 is Second track member 31 The second raceway member 31 has a raceway member recess 32a for accommodating the annular protrusion 31b. As shown in FIG. 2, the control member 32 has an inner peripheral surface formed with a key groove 32b for engaging with the key of the input shaft (not shown) or the output shaft (not shown).

[0023] The control elastic member 33 has a portion that moves in the radial direction when elastically deformed, and the portion that moves in the radial direction functions as the second lock engagement portion 33d. In this embodiment, the control elastic member 33 is formed as a control spring 33. More specifically, the control spring 33 of this embodiment is formed in the shape of a leaf spring, and as shown in FIG. 4, has a first annular portion 33a formed in a ring shape connected in the circumferential direction and fixed to the control member 32, a second annular portion 33b formed in a ring shape connected in the circumferential direction and fixed to the selector member 36, and a plurality of bent pieces 33c (bent in a dogleg shape) that are arranged in a line in the circumferential direction and connect the first annular portion 33a and the second annular portion 33b, which are arranged apart in the axial direction X, in the axial direction X, and each bent piece 33c is formed to move radially upon elastic deformation. As shown in FIG. 4, circumferential gaps are formed between the multiple bent pieces 33c, and the bending angle of each bent piece 33c changes with movement of the selector member 36 (second annular portion 33b) relative to the control member 32 (first annular portion 33a) in the axial direction X, and accordingly, the bent piece 33c functioning as a second locking engagement portion 33d described later moves radially. In addition, the bent piece 33c functioning as the second locking engagement portion 33d is configured to come into contact with the first locking engagement portion 22d of the first track member unit 20 and be pushed radially inward and moved when the second track member unit 30 is brought closer to the first track member unit 20 in the axial direction X from the state shown in FIG. 7. In the above, the first locking engagement portion 22d has been described as being formed in a ring-like and convex shape on the inner circumferential wall of the casing 22. However, it is not necessary to form the first locking engagement portion 22d in a circumferentially connected manner, and a plurality of first locking engagement portions 22d may be formed in a line in the circumferential direction.

[0024] The biasing spring 35 is made of a coil spring and is arranged in a compressed state between the second track member 31 and the control member 32 as shown in Figures 6 and 7, and functions as a biasing means that biases the second track member 31 and the control member 32 so as to move them away from each other.

[0025] In this embodiment, the above-mentioned input shaft (not shown) or output shaft (not shown) is inserted into the through holes of the second track member 31 and the control member 32 and connected to the second track member 31 and the control member 32, but the connection manner of the input shaft (not shown) or the output shaft (not shown) may be any, such as connecting to only one of the second track member 31 or the control member 32.

[0026] As shown in Figures 3 and 5, the cam unit 40 includes a plurality of cams 41 arranged between the first track member 21 and the second track member 31 in the axial direction X, an annular cam cage 42 capable of holding the plurality of cams 41, and a posture-maintaining spring 43 (shown in Figures 6 and 7).

[0027] As shown in Figures 3 and 6, the multiple cams 41 are held by a cam cage 42 and are arranged in a ring shape (circumferential direction) around the rotation axis of the first track member 21 (and the second track member 31) between the annular first track surface 21a and the annular second track surface 31a in the axial direction X. Each cam 41 is held by the cam cage 42 in a state in which it can roll (tilt) about an axis that is not parallel to the axial direction X (in this embodiment, an axis along the radial direction of the first track member 21 and the second track member 31 that is perpendicular to the axial direction X). In this embodiment, all of the cams 41 are formed identically. When the first track member 21 and the second track member 31 are rotated relative to each other while being sandwiched between them in the axial direction X, the cams 41 roll due to contact (friction, frictional engagement) with the first track surface 21a and the second track surface 31a, both during rotation in one direction and during rotation in the other direction, so that the height of the cam 41 in the axial direction X changes (becomes larger than when in a neutral state described later) and the cam 41 functions as a strut between the first track surface 21a and the second track surface 31a, thereby transmitting torque between the first track member 21 and the second track member 31.

[0028] As shown in Figs. 2 and 5, the cam cage 42 is formed in a disk shape having a through hole at the center thereof penetrating in the axial direction X along the rotation axis of the first raceway member 21 (and the second raceway member 31). As shown in FIG. 2 and FIG. 5, the cam cage 42 is formed to penetrate in the axial direction X, and has a plurality of cam holding portions 42a for holding the cams 41 in the circumferential direction. 2 and 5, each cam holding portion 42a is formed to receive a cam 41 from the first track member 21 side of the cam cage 42 in the axial direction X. Each cam 41, while held by each cam holding portion 42a, can slip out toward the first track member 21 side, but is supported by each cam holding portion 42a so as to be prevented from slipping out toward the second track member 31 side.

[0029] As shown in Figures 6 and 7, the posture-maintaining spring 43 is arranged in a compressed state between the casing 22 and the cam cage 42 and biases the cam cage 42 toward the first track member 21 in the axial direction X. This maintains each cam 41 in (constant) contact with the first track surface 21a of the first track member 21, and as a result, the posture of each cam 41 is maintained in a neutral state (a state in which the height of the cam 41 in the axial direction X is lower than a state in which the cam 41 functions as a strut between the track surfaces 21a, 31a and can transmit torque between the track surfaces 21a, 31a).

[0030] The cam clutch 10 includes a locking mechanism for releasably locking the positional distance between the first and second track members 21 and 31 in the axial direction X while a cam 41 is sandwiched between the first and second track members 21 and 31 so that torque can be transmitted between the first and second track members 21 and 31.

[0031] As shown in Figures 6 and 7, the locking mechanism comprises a first locking engagement portion 22d of the first track member unit 20 and a second locking engagement portion 33d of the second track member unit 30 that is engageable with the first locking engagement portion 22d. The engagement between the first locking engagement portion 22d and the second locking engagement portion 33d prevents the second track member 31 from separating from the first track member 21 in the axial direction X. In other words, the first track surface 21a and the second track surface 31a are configured to maintain a state in which they are in contact with the cam 41.

[0032] In this embodiment, as shown in Figures 4 and 6, the second lock engagement portion 33d is formed of a bent piece 33c of the control spring 33, and the second lock engagement portion 33d is configured to move in a radial direction perpendicular to the axial direction X in accordance with the movement of the selector member 36 (second annular portion 33b) relative to the control member 32 (first annular portion 33a) in the axial direction X.

[0033] Next, a method of operation of the cam clutch 10 in this embodiment will be described below.

[0034] First, Fig. 7 shows the cam clutch 10 in a state (idling state) in which no torque is transmitted between the first raceway member 21 and the second raceway member 31. In the state shown in Fig. 7, the first raceway member 21 and the second raceway member 31 are separated in the axial direction X, and the second raceway surface 31a of the second raceway member 31 is not in contact with the cam 41. Also, in the state shown in Fig. 7, the cam cage 42 is biased by the position-maintaining spring 43, so that each cam 41 is in contact with the first raceway surface 21a of the first raceway member 21.

[0035] Next, when transitioning from the state shown in FIG. 7 to a torque transmission state in which torque can be transmitted between the first track member 21 and the second track member 31, the first track member 21 and the second track member 31 are moved relatively closer to each other in the axial direction X by a driving means (not shown) provided separately from the cam clutch 10, and the second track surface 31a of the second track member 31 is brought into contact with the multiple cams 41.

[0036] At this time, the bent piece 33c of the control spring 33 functioning as the second locking engagement portion 33d abuts against the first locking engagement portion 22d of the first track member unit 20, and the bent piece 33c elastically deforms and moves radially inward to overcome the first locking engagement portion 22d toward the first track member 21 (the upper side in FIG. 7). After overriding, the bent piece 33c elastically returns to its original shape and moves radially outward toward an engagement position where it can engage with the first locking engagement portion 22d. As a result, the second locking engagement portion 33d automatically engages with the first locking engagement portion 22d, and the second track member 31 is prevented from separating from the first track member 21 in the axial direction X. In this embodiment, the various parts of the cam clutch 10 are configured so that the engagement of the second locking engagement portion 33d with the first locking engagement portion 22d is completed after the second track surface 31a comes into contact with each cam 41. However, the various parts of the cam clutch 10 may be configured so that the engagement of the second locking engagement portion 33d with the first locking engagement portion 22d is completed at the same time as the second track surface 31a comes into contact with each cam 41. In addition, in order to enable the bent piece 33c of the control spring 33 to smoothly ride over the first locking engagement portion 22d in the axial direction X, an inclined surface (tapered surface) 22d' whose diameter decreases from the bottom to the top is formed on the lower side (the second track member unit 30 side) of the first locking engagement portion 22d, as shown in FIG. 7.

[0037] At this time, the second track member 31 is movable in the axial direction X relative to the control member 32, and since the biasing spring 35 is installed between the second track member 31 and the control member 32, the multiple cams 41 can be smoothly brought into contact with the second track surface 31a of the second track member 31. Therefore, when operating the second track member unit 30 by the above-mentioned driving means (not shown), it is preferable to operate the control member 32, not the second track member 31.

[0038] Next, as shown in FIG. 6, with the cam 41 sandwiched between the first track member 21 and the second track member 31 in the axial direction X, the first track member 21 and the second track member 31 rotate relatively (i.e., the input shaft rotates), whereby each cam 41 rolls due to friction (frictional engagement) between the track surfaces 21a, 31a, and the height of the cam 41 in the axial direction X changes (becomes larger), allowing torque to be transmitted between the first track member 21 and the second track member 31.

[0039] Regarding the relative rotation of the track members 21, 31 (i.e., rotation of the input shaft), the first track member 21 and the second track member 31 may be rotated relative to each other (i.e., the input shaft may be rotated) before the cam 41 is sandwiched between the first track member 21 and the second track member 31, or the first track member 21 and the second track member 31 may not be rotated relative to each other before the cam 41 is sandwiched between the first track member 21 and the second track member 31, and the first track member 21 and the second track member 31 may be rotated relative to each other after the cam 41 is sandwiched between the first track member 21 and the second track member 31.

[0040] Next, when transitioning from a torque transmission state in which torque can be transmitted between the first track member 21 and the second track member 31 to a state in which torque is not transmitted between the first track member 21 and the second track member 31 (idling state), first, the engagement of the second locking engagement portion 33d with the first locking engagement portion 22d is released.

[0041] At this time, by using an operating means (not shown) provided separately from the cam clutch 10, the selector member 36 is moved in a direction (downward in FIG. 6) relative to the control member 32 away from the first track member 21, whereby the bent piece 33c of the control spring 33 functioning as the second locking engagement portion 33d is moved radially inward and overcomes the first locking engagement portion 22d, thereby releasing the engagement of the second locking engagement portion 33d with the first locking engagement portion 22d. In order to enable the bent piece 33c of the control spring 33 to smoothly ride over the first lock engagement portion 22d in the axial direction X, an inclined surface (tapered surface) 22d'' having a diameter that decreases from the top to the bottom is formed on the upper side (the first lock engagement portion 22d side) of the first lock engagement portion 22d, as shown in FIG. 7.

[0042] Then, simultaneously with or after the disengagement of the second locking engagement portion 33d from the first locking engagement portion 22d, the first track member 21 and the second track member 31 are separated in the axial direction X (the second track member 31 is separated from the cam 41) by a driving means (not shown) provided separately from the cam clutch 10, whereby a transition to a state in which no torque is transmitted between the first track member 21 and the second track member 31 (an idling state) can be made as shown in FIG. 7. The entire second track member unit 30 including the second track member 31 may be moved in the axial direction X by the operation of moving the selector member 36 in a direction away from the first track member 21 (downward in FIG. 6) by the above-mentioned operating means (not shown). In this case, as shown in FIG. 7, a movement restricting protrusion 37 against which the selector member 36 moved downward hits may be provided on the lower side of the selector member 36 (the side moving away from the first track member 21) on the outer periphery side of the control member 32. When such a movement restricting protrusion 37 is provided, after the selector member 36 moved downward hits the movement restricting protrusion 37, the control member 32 can be moved downward via the movement restricting protrusion 37 by an operation of moving the selector member 36 downward. In the example shown in FIG. 7, the movement restricting protrusion 37 is composed of a ring fitted on the outer periphery side of the control member 32, but the specific form of the movement restricting protrusion 37 may be any as long as it is abutted by the selector member 36 moved downward.

[0043] Furthermore, the transition operation from the torque transmission state in which torque can be transmitted between the first track member 21 and the second track member 31 to a state in which torque is not transmitted between the first track member 21 and the second track member 31 (idling state) may be performed while torque is being transmitted between the first track member 21 and the second track member 31, or may be performed when the relative rotation between the first track member 21 and the second track member 31 is stopped.

[0044] Although the embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various design modifications can be made without departing from the scope of the present invention described in the claims. For example, the cam clutch 10 may be configured by arbitrarily combining the configurations of the above or following embodiments and modified examples.

[0045] For example, in the above-described embodiment, the first track member 21 and the second track member 31 are described as being formed in an annular (ring-shaped) shape with a through hole in the center, but the through hole does not have to be formed, in other words, they do not have to be formed in an annular (ring-shaped) shape.

[0046] In the above embodiment, it has been described that the state in which each cam 41 is in contact with the first track surface 21a of the first track member 21 is maintained even in the idling state. However, the cams 41 may be configured not to contact either the first track surface 21a of the first track member 21 or the second track surface 31a of the second track member 31 in the idling state.

[0047] In addition, in the above-described embodiment, all of the cams 41 are formed identically, and each cam 41 is formed so that when the first track member 21 and the second track member 31 are sandwiched between them and the first track member 21 and the second track member 31 are rotated relative to each other, the cams roll to change (increase) their height in the axial direction X, thereby transmitting torque between the first track member 21 and the second track member 31, both during rotation in one direction and during rotation in the other direction. However, at least a portion of the multiple cams 41 (e.g., half of the cams 41) may be configured to roll to change (increase) their height in the axial direction X when the first track member 21 and the second track member 31 are rotated relatively in one direction, thereby transmitting torque between the first track member 21 and the second track member 31, and at least a portion of the multiple cams 41 (e.g., the remaining half of the cams 41) may be configured to roll to change (increase) their height in the axial direction X when the first track member 21 and the second track member 31 are rotated relatively in the other direction, thereby transmitting torque between the first track member 21 and the second track member 31. Furthermore, all of the cams 41 may be configured so that when the first track member 21 and the second track member 31 are rotated relative to each other while being sandwiched between the first track member 21 and the second track member 31, the height in the axial direction X changes (becomes larger) by rolling only during rotation in one direction, thereby transmitting torque between the first track member 21 and the second track member 31; in other words, the cam clutch 10 may be configured as a so-called one-way clutch. Furthermore, the specific aspects of the cam 41 and the cam cage 42 (such as the shapes of the cam 41 and the cam cage 42, and the manner in which the cam 41 is held by the cam cage 42) are not limited to the above (as shown in Figure 5), and may be any, such as one that constitutes a so-called sprag clutch.

[0048] In the above embodiment, the locking mechanism for releasably locking the positional gap between the first track member 21 and the second track member 31 in the axial direction X has been described as being composed of the first locking engagement portion 22d of the first track member unit 20 and the second locking engagement portion 33d of the second track member unit 30 which is movable in the radial direction. However, to configure the locking mechanism, it is sufficient to provide at least one of the first locking engagement portion 22d or the second locking engagement portion 33d to be movable in the radial direction. Furthermore, in the case where the first locking engagement portion 22d is provided to be movable in the radial direction, it is preferable to bias the first locking engagement portion 22d (by one or more elastic members such as springs or rubber provided integrally or separately from the first locking engagement portion 22d) toward an engagement position where it can engage with the second locking engagement portion 33d (so that the first locking engagement portion 22d elastically returns to the engagement position). Furthermore, in the case where the second lock engagement portion 33d is provided to be movable in the radial direction, it is preferable to bias the second lock engagement portion 33d (by one or more elastic members such as springs or rubber provided integrally with or separately from the second lock engagement portion 33d) toward an engagement position where it can engage with the first lock engagement portion 22d (so that the second lock engagement portion 33d elastically returns to the engagement position). More specifically, in the above embodiment, the control elastic member 33 having the second locking engagement portion 33d has been described as the control spring 33 as shown in Fig. 4. However, the specific form of the control elastic member 33 may be any as long as it is formed as an elastic member such as a spring or rubber and has a ring-shaped second locking engagement portion 33d that elastically deforms to contract and expand in diameter, or has a portion that functions as the second locking engagement portion 33d that moves in the radial direction when elastically deformed, and may be, for example, a ring made of synthetic rubber or the like attached to the outer periphery of the control member 32. In addition, the number of control elastic members 33 is not limited to one, and a plurality of control elastic members 33 having the second locking engagement portion 33d may be provided.

[0049] In the above-described embodiment, the multiple cams 41 have been described as being arranged in a single annular row around the rotation axis of the first track member 21 (and the second track member 31) between the annular first track surface 21a and the annular second track surface 31a in the axial direction X, as shown in Figures 3 and 6. However, the arrangement of the cams 41 is not limited to the above, and the cams 41 may be arranged, for example, such that multiple annular rows of the cams 41 arranged in the circumferential direction are arranged in the radial direction (in other words, the cams 41 are arranged in double rows in the radial direction). [Explanation of symbols]

[0050] 10 Cam clutch 20 First track member unit 21 First raceway member 21a... 1st orbital plane 22 Casing 22a ... Recess for track member 22b Cam recess 22c Spring recess 22d First locking engagement portion 30 Second track member unit 31 Second raceway member 31a... 2nd orbital plane 31b... Annular protrusion 31c Keyway 32 Control member 32a ... Recess for track member 32b Key groove 33 Control spring (control elastic member) 33a... 1st annular part 33b...Second annular part 33c: Bent piece 33d Second locking engagement portion 34 ··· Volts 35 .... Biasing spring (biasing means) 36 Selector member 40 Cam unit 41 Cam 42 Cam cage 42a Cam holder 43 ··· Posture maintaining spring X... Axial direction

Claims

1. A cam clutch comprising a rotatably mounted first raceway member, a second raceway member rotatably mounted coaxially with the first raceway member, and a plurality of cams disposed between the first raceway member and the second raceway member, the first raceway member and the second raceway member are spaced apart in an axial direction along a rotational axis of the first raceway member, the plurality of cams are disposed between the first raceway member and the second raceway member in the axial direction, the first raceway member and the second raceway member are provided so as to be movable toward and away from each other in an axial direction, the first raceway member has a first raceway surface formed in an annular shape around a rotation axis of the first raceway member on a side facing the second raceway member, the second raceway member has a second raceway surface formed annularly about a rotation axis of the second raceway member on a side facing the first raceway member, a first raceway member that is disposed between the first raceway member and the second raceway member, the first raceway member being configured to rotate about a rotation axis of the first raceway member;

2. 2. The cam clutch according to claim 1, wherein each of the cams is designed so that when the first raceway member and the second raceway member are rotated relative to each other while being sandwiched between the first raceway member and the second raceway member in the axial direction, the cams roll to change their height in the axial direction in both the one-way rotation and the other-way rotation, thereby transmitting torque between the first raceway member and the second raceway member.

3. a cam cage capable of holding the plurality of cams; 3. The cam clutch according to claim 1, wherein the cam cage is biased toward the first raceway member, so that the cams are maintained in contact with the first raceway member.

4. The cam cage has a plurality of cam holding portions for holding the cams, 4. The cam clutch according to claim 3, wherein the cam holding portion is formed to receive the cam from the first raceway member side of the cam cage in the axial direction.

5. a first track member unit having the first track member and a second track member unit having the second track member, The first track member unit has a first locking engagement portion, the second track member unit has a second locking engagement portion engageable with the first locking engagement portion, When the second locking engagement portion is engaged with the first locking engagement portion, the second track member is prevented from being separated from the first track member in the axial direction, 5. The cam clutch according to claim 1, wherein at least one of the first locking engagement portion and the second locking engagement portion is provided so as to be movable in a radial direction perpendicular to the axial direction.

6. The second track member unit has a control elastic member, the control elastic member has a portion that moves in a radial direction when elastically deformed, 6. The cam clutch according to claim 5, wherein the radially movable portion functions as the second locking engagement portion.

7. the second track member unit has a control spring as the control elastic member, the control spring has a first annular portion and a second annular portion that are spaced apart in the axial direction, and a plurality of bent pieces that are arranged side by side in the circumferential direction and connect the first annular portion and the second annular portion in the axial direction, and is formed so that each of the bent pieces moves in a radial direction when the control spring is elastically deformed; 7. The cam clutch according to claim 6, wherein each of the bent pieces functions as the second locking engagement portion.

8. a first track member unit having the first track member and a second track member unit having the second track member, the second track member unit includes a control member disposed axially movable relative to the second track member on a rear side opposite to a front side facing the first track member in the axial direction, and a biasing means for biasing the second track member and the control member so as to move them away from each other, The first track member unit has a first locking engagement portion, the second track member unit has a second locking engagement portion engageable with the first locking engagement portion, 8. The cam clutch according to claim 1, wherein the second locking engagement portion is formed to engage with the first locking engagement portion so as to prevent the control member from separating from the first raceway member in the axial direction.

Images