Selectable clutch

Abstract

To provide a selectable clutch having a simple structure, high responsiveness, and less backlash and noise, and enabling switching operation with a light force even when transmission torque is large.SOLUTION: Each of rotation transmission paths, in which a first clutch mechanism 130, configured to be able to transmit rotation between two rotary elements 110, 115 by the wedge effect and frictional force of a locking member 132, and a second clutch mechanism 140, configured to be able to transmit rotation by meshing two engagement elements 141, 146, are arranged, is provided with a buffer element that allows one or both of the engagement elements to move circumferentially relative to the rotary element to which the engagement element is connected.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a selectable clutch that is configured to be able to switch the operation of at least one of a first clutch mechanism that transmits / blocks rotation of an input shaft in one direction to an output shaft and a second clutch mechanism that transmits / blocks rotation of the input shaft in the other direction to the output shaft. [Background technology]

[0002] As a clutch that controls the transmission and interruption of rotation between two shafts, a two-way clutch that can switch between driving and idling in both the forward and reverse directions is known. Although devices consisting of ratchet clutches or dog clutches are well known, they can only transmit rotation at a specified rotation angle, and because they transmit rotation through rigid engagement, they are prone to rattle and produce a lot of noise. Some types of two-way clutches are configured to switch between a locked state, which prohibits relative rotational movement between the inner and outer rings (transmits rotational force), and a free state, which allows relative rotational movement between the inner and outer rings (blocks rotational force), by tilting a cam or sprag, making it possible to transmit rotation at any rotation angle (see, for example, Patent Document 1 and Patent Document 2).

[0003] Furthermore, Patent Document 3 describes a two-way clutch equipped with a switching mechanism that can switch between three operating modes, two-way free mode, one-way lock mode, and two-way lock mode, by controlling a retainer that holds a roller, which serves as a power transmission member, in a neutral position or one of the engagement positions of a cam surface formed on the inner circumference of the outer ring, and that can transmit rotation at any rotation angle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-220509 [Patent Document 2] Japanese Patent Application Publication No. 11-182589 [Patent Document 3] Japanese Patent Application Laid-Open No. 2014-219015 [Patent Document 4] Japanese Patent Publication No. 2020-190255 Summary of the Invention [Problem to be solved by the invention]

[0005] In the two-way clutch described in Patent Document 1, when the input rotor rotates relative to the output rotor, the sprags tilt in the same direction as the rotation of the input rotor, switching between engagement and disengagement between the input rotor and the output rotor. This causes a time loss when the rotation direction is switched, resulting in poor responsiveness. The two-way clutch described in Patent Document 2 also has the same problem. The two-way clutch described in Patent Document 3 is capable of transmitting power in both directions simultaneously using a leaf spring-like member, but because power is transmitted by friction, there is a problem in that the torque that can be transmitted is small compared to the size of the two-way clutch. Furthermore, in order to solve these problems and provide a cam clutch that has a simple structure, is capable of switching between operation modes, has high responsiveness, and can ensure the desired torque capacity, the applicant invented a cam clutch with an operation mode switching mechanism shown in Patent Document 4.

[0006] However, in a clutch that locks these cams or rollers by pinching them together, the cams or rollers can be locked in any position in either direction, and a slight relative rotation from the start of torque transmission causes the cams or rollers to strongly mesh and transmit torque. Therefore, in two-way lock mode, even if the rotational torque is eliminated, the slight relative rotation when one cam or roller is released from its meshing will cause the other cam or roller to mesh, and the meshing will remain on the cams and rollers in both directions. In order to switch to two-way free mode or one-way lock mode in this state, a force is required to release the engagement of the cams and rollers. Since the engagement also increases as the transmitted torque increases, it was necessary to provide a switching mechanism with a structure capable of generating a large force when transmitting a large torque.

[0007] The present invention aims to solve these problems and to provide a selectable clutch that has a simple structure, is capable of switching operating modes, is highly responsive, can ensure the desired torque capacity, has little backlash or noise, and can be switched with little force even when the transmission torque is large. [Means for solving the problem]

[0008] The present invention provides a selectable clutch comprising a first shaft element and a second shaft element, one of which is an input shaft and the other of which is an output shaft, a first clutch mechanism disposed in a first rotation transmission path that transmits rotation in one direction of the input shaft to the output shaft, a second clutch mechanism disposed in a second rotation transmission path that transmits rotation in the other direction of the input shaft to the output shaft, and an operating mechanism that switches the operation of either or both of the first clutch mechanism and the second clutch mechanism, wherein the first clutch mechanism is configured to operate by utilizing a wedge effect of a locking member that is disposed in a state biased by a biasing means between the first rotating element and the second rotating element that are coaxially provided so as to be rotatable relative to each other. and is configured to be able to transmit rotation at any rotation angle by frictional forces between the locking member and the first and second rotating elements, and the second clutch mechanism is configured to be able to transmit rotation at a predetermined rotation angle by meshing an engaging portion of a first engaging element connected to the first rotating element with an engaging portion of a second engaging element connected to the second rotating element, and the above problem is solved by configuring each of the first rotation transmission path and the second rotation transmission path to have a buffer element that allows either or both of the first engaging element and the second engaging element to move circumferentially relative to the rotating elements to which the engaging element is connected. [Effects of the Invention]

[0009] According to the invention of claim 1, in the bidirectional lock mode capable of transmitting rotation in both directions, the first clutch mechanism is configured to transmit rotation at any rotation angle by the wedge effect of the locking member and frictional force obtained by the relative rotation of the first and second rotating elements, thereby enabling rotation transmission without backlash in both directions. Furthermore, the second clutch mechanism limits the meshing position between the engaging portion of the first engaging element and the engaging portion of the second engaging element, and the action of buffer elements disposed in the first and second rotation transmission paths creates rotational play when the rotational load state changes, allowing the clutch mechanism to disengage for the amount of rotational play. Therefore, both the first and second clutch mechanisms are never engaged at the same time, allowing for easy switching even with a large transmission torque. Furthermore, in one-way lock mode, which allows rotation to be transmitted in only one direction, the second clutch mechanism is disengaged and the first clutch mechanism is used to operate the gears, enabling relative rotation with extremely little noise or rotational resistance.

[0010] According to the configuration of claim 2, the displacement caused by the relative movement between the engaging element and the rotating element is returned by the action of the spring element, thereby maintaining a state in which rotational play can be generated in preparation for changes in the rotational load state, and more reliably preventing both the first clutch mechanism and the second clutch mechanism from being engaged at the same time. According to the configuration of claim 3, it is possible to generate rotational play due to the backlash of the spline, and the rotational play may be of a size equivalent to the amount of elastic deformation of the engaging portion that occurs when the engaging portion of the first engaging element and the engaging portion of the second engaging element engage with each other, so it is possible to rotate the rotating element and the engaging element relative to each other without impeding smooth rotational transmission. According to the configuration of claim 4, with a simple configuration, it is possible to realize connection between the rotating element and the engaging element by utilizing a spring force in the radial direction, while generating play due to relative movement between the rotating element and the engaging element in the circumferential direction, and it is possible to return the displacement caused by the relative movement to a state ready for switching of the rotational load state. According to the configuration of claim 5, the first clutch mechanism is configured as a cam-type one-way clutch, which makes it possible to switch the operating mode of the first clutch mechanism with a simple structure, and also ensures high responsiveness and the desired torque capacity. According to the invention of claim 6, the second clutch mechanism is configured as a ratchet-type one-way clutch, thereby ensuring high responsiveness and a desired torque capacity. According to the configuration of the present invention, the operation of the second clutch mechanism can be switched by a simple operation of moving the operating mechanism in the axial direction. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is an exploded perspective view showing the configuration of a selectable clutch according to one embodiment of the present invention. FIG. [Figure 2] 2 is a partially cutaway perspective view of the selectable clutch shown in FIG. 1. FIG. [Figure 3] 2 is a cross-sectional view of the cam clutch shown in FIG. 1 taken along a plane along the rotation axis. [Figure 4] 2 is a cross-sectional view of the selectable clutch shown in FIG. 1 taken along a plane perpendicular to the rotation axis. [Figure 5] FIG. 2 is a diagram illustrating a configuration of a buffer element. [Figure 6] FIG. 10 is a schematic diagram showing a state where jamming occurs. [Figure 7A] 2 is a schematic diagram showing a state in which the ratchet pawl is moved to a position where it engages with the ratchet teeth when the operating mode of the selectable clutch shown in FIG. 1 is set to a bidirectional lock mode. FIG. [Figure 7B]FIG. 10 is a schematic diagram showing a state in which rotation is transmitted by a second clutch mechanism. [Figure 8A] 4 is a schematic diagram showing a state when the cam in the first clutch mechanism starts to mesh when the operating mode of the selectable clutch shown in FIG. 1 is set to a bidirectional lock mode. FIG. [Figure 8B] FIG. 4 is a schematic diagram showing a state in which rotation is transmitted by a first clutch mechanism. [Figure 9] 2 is a cross-sectional view taken along a plane along the rotation axis when the operation mode of the selectable clutch shown in FIG. 1 is set to a one-way lock mode. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Examples of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. [Example]

[0013] 1 to 4, in a selectable clutch 100 according to one embodiment of the present invention, the first rotating element is made up of an outer ring 110, and the second rotating element is made up of an inner ring 115 that is provided coaxially with the outer ring 110 and capable of relative rotation. The symbol C in FIGS. 2 to 4 indicates the rotation axis. The outer ring 110 has an outer peripheral surface on which splines 111 are formed, extending in the axial direction. Axial splines 116 are formed on the inner peripheral surface of inner ring 115. One axial end of the outer peripheral surface of inner ring 115 is formed with a circumferential groove 117 that extends over the entire periphery.

[0014] The first shaft element 120, which is connected to the outer ring 110, which is the first rotating element, is configured to have a case shape capable of accommodating the outer ring 110 therein, and has a cylindrical shaft portion 121 and a circular plate-shaped lid portion 123 that is screwed and fixed to the other axial end face of the cylindrical shaft portion 121. A spline 122 extending in the axial direction is formed on the inner peripheral surface of the cylindrical shaft portion 121. The second shaft element 125, which is connected to the inner ring 115, which is the second rotating element, is configured to form a spline connection structure with the splines 116 of the inner ring 115, for example by an interference fit, and has a cylindrical shaft portion 126 and a flange portion 127, which is located at a position overlapping with the inner ring 115 in the axial direction of the cylindrical shaft portion 126 and has splines 128 formed on its outer surface that extend in the axial direction. In the following, in this embodiment, for example, the second shaft element 125 is described as the input shaft and the first shaft element 120 as the output shaft, but the first shaft element 120 may be the input shaft and the second shaft element 125 may be the output shaft.

[0015] The first clutch mechanism 130 is disposed in a first rotation transmission path that transmits the rotation of the second shaft element 125 in one direction to the first shaft element 120 . The first clutch mechanism 130 is a cam-type one-way clutch in which the locking member is composed of a cam 132, and is configured to be able to transmit unidirectional rotation of the first shaft element 120 to the second shaft element 125 at any rotation angle by the wedge effect of the cam 132 and the frictional force between the cam 132 and the outer ring 110 and inner ring 115. Specifically, the first clutch mechanism 130 comprises a cage ring 131 arranged coaxially with the outer ring 110 and the inner ring 115 between the outer ring 110 and the inner ring 115, a plurality of cams 132 and a plurality of rollers 133 held by the cage ring 131 and arranged circumferentially in the annular space between the inner surface of the outer ring 110 and the outer surface of the inner ring 115, and an annular spring 134 which is a biasing means for biasing each of the plurality of cams 132 so as to contact the outer ring 110 and the inner ring 115.

[0016] The second clutch mechanism 140 is disposed on a second rotation transmission path that transmits the rotation of the second shaft element 125 in the other direction to the first shaft element 120 . The second clutch mechanism 140 is a ratchet-type one-way clutch configured to be able to transmit rotation in the other direction of the input shaft to the output shaft at a predetermined rotation angle by engaging the ratchet pawl 142 with the ratchet teeth 147. The first engaging element is constituted by a ratchet pawl holding member 141 in the shape of an annular plate having a ratchet pawl 142 as an engaging portion. On the outer peripheral surface of the ratchet pawl holding member 141, splines 143 are formed that extend axially continuously with the splines 111 of the outer ring 110. The second engaging element is constituted by a ratchet tooth holding member 146 in the form of an annular plate having ratchet teeth 147 as an engaging portion. On the inner peripheral surface of the ratchet tooth holding member 146, splines 148 are formed that are configured to form a spline coupling structure with the splines 128 of the second shaft element 125 by, for example, an interference fit. In this embodiment, the ratchet pawl holding member 141 is provided on the other axial end surface of the outer ring 110, and the ratchet tooth holding member 146 is fixed to the other axial end surface of the inner ring 115 so that the ratchet teeth 147 face the ratchet pawl 142 in the axial direction.

[0017] The operating mechanism 150 in this embodiment is configured to move the inner ring 115 axially relative to the outer ring 110 to separate the ratchet tooth holding member 146 and the ratchet pawl holding member 141, thereby switching between a state in which rotation in the other direction of the input shaft can be transmitted and a state in which rotation transmission in both directions of the input shaft is blocked. Therefore, the selectable clutch 100 can switch its operating mode between a bidirectional lock mode in which rotation of the second shaft element 125 in both directions can be transmitted to the first shaft element 120, and a one-directional lock mode in which rotation of the second shaft element 125 in only one direction can be transmitted to the first shaft element 120 via the first rotation transmission path.

[0018] The operating mechanism 150 has a selector member 151 in the shape of an annular plate fitted onto one axial end of the inner ring 115. The selector member 151 is fixed integrally to each of a plurality of fixing members 152 in the shape of partial annular plates which are fitted into the circumferential groove 117 of the inner ring 115 at positions spaced apart from each other in the circumferential direction.

[0019] Thus, this selectable clutch 100 is provided with a buffer element 160 in each of the first rotation transmission path and the second rotation transmission path that allows the ratchet pawl holding member 141 to move circumferentially relative to the outer ring 110, and a spring element that restores displacement caused by relative movement between the ratchet pawl holding member 141 and the outer ring 110.

[0020] The buffer element 160 in this embodiment is configured by connecting the ratchet pawl holding member 141 to the outer ring 110 so as to be relatively movable in the circumferential direction, and by connecting the outer ring 110 and the ratchet pawl holding member 141 to the first shaft element 120 so as to form a spline connection structure by a loose fit, as shown in Fig. 5. The backlash amount S is a size that allows smooth rotation transmission between the outer ring 110 and the first shaft element 120, and is a size that corresponds to the amount of elastic deformation of each of the ratchet pawl 142 and the ratchet teeth 147 that occurs when the ratchet pawl 142 and the ratchet teeth 147 mesh with each other. Although not shown, the spline connection structure between the ratchet pawl holding member 141 and the first shaft element 120 is configured in the same manner as the spline connection structure between the outer ring 110 and the first shaft element 120.

[0021] The ratchet pawl holding member 141 and the outer ring 110 are connected by a first spring pin 165 and a solid pin member 166. Connecting the ratchet pawl holding member 141 and the outer ring 110 by the pin member 166 prevents the ratchet pawl holding member 141 from accidentally coming off the outer ring 110. As shown in FIG. 3, the first spring pin 165 is formed by winding an elastic thin plate into a cylindrical shape and creating a cut in a portion of its circumference that extends in a direction intersecting the circumferential direction, and is inserted into the insertion hole 112 provided in the outer ring 110 and the through hole 144 provided in the ratchet pawl holding member 141 so as to resiliently expand in the radial direction. 3, the pin member 166 is fitted into an insertion hole 112 provided in the outer ring 110, and is inserted into a through hole 144 provided in the ratchet pawl holding member 141 with a gap formed between the pin member 166 and the through hole 144. The gap is set to be larger than the backlash amount S, so that the relative movement (relative rotation) of the ratchet pawl holding member 141 in the circumferential direction with respect to the outer ring 110 is not hindered. In this embodiment, the first spring pins 165 and the pin members 166 are arranged alternately at positions spaced apart at equal intervals on the same circumference centered on the rotation axis.

[0022] The spring elements in each of the first and second rotation transmission paths are constituted by a first spring pin 165 that elastically fastens the outer ring 110 and the ratchet pawl holding member 141, and are capable of restoring displacement that occurs due to relative movement of the ratchet pawl holding member 141 with respect to the outer ring 110. In this embodiment, the number of first spring pins 145 is three, but the number of first spring pins 145 is not limited, and by adjusting the number of first spring pins 145, it is possible to appropriately adjust the load associated with the relative circumferential movement of the ratchet pawl holding member 141 with respect to the outer ring 110.

[0023] The operation of the selectable clutch 100 configured as above will now be described. The state shown in Figures 2 to 4 is a state in which the operating mode of the selectable clutch 100 is set to the bidirectional lock mode, in which rotation in one direction of the second shaft element 125 can be transmitted to the first shaft element 120 via the first clutch mechanism 130, and rotation in the other direction of the second shaft element 125 can be transmitted to the first shaft element 120 via the second clutch mechanism 140.

[0024] Therefore, in a configuration in which a cam-type one-way clutch and a ratchet-type one-way clutch are simply combined, in the bidirectional lock mode, as shown in FIG. 6, when the input torque to the second shaft element 125 is switched to change the rotational load state, slight torques T1 and T2 that oppose the input torque act on both the cam 132 and the ratchet mechanism formed by the ratchet pawl 142 and ratchet teeth 147. However, in the above-mentioned selectable clutch 100, by providing the first rotation transmission path and the second rotation transmission path with a buffer element 160 and a first spring pin 165 which is a spring element, when the rotational load state changes, the outer ring 110 and the ratchet pawl holding member 141 rotate relative to each other, causing rotational play, and the clutch mechanism is not engaged for the amount of rotation of the play.

[0025] Specifically, when the rotational load state is switched from a state in which cam 132 is meshed with outer ring 110 and inner ring 115 due to input of rotational torque in one direction to second shaft element 125 to a state in which rotational torque in the other direction is input to second shaft element 125, as shown in Fig. 7A, ratchet pawl 142 comes into contact with ratchet teeth 147, causing ratchet pawl holder 141 to move relative to outer ring 110 in the circumferential direction by the amount of backlash S. Note that Fig. 7A exaggerates the state in which spline 143 of ratchet pawl holder 141 is displaced relative to spline 111 of outer ring 110. While ratchet pawl holder 141 is moving relative to outer ring 110, the torque acting on cam 132 (T1 shown in Fig. 6) disappears. When the ratchet pawl holding member 141 moves relative to the outer ring 110 by the amount of backlash S and the spline 143 of the ratchet pawl holding member 141 comes into contact with the spline 122 of the first shaft element 120, as shown in Figure 7B, the ratchet pawl 142 and the ratchet teeth 147 mesh together, causing a torque T2 to act and transmitting rotation to the first shaft element 120, and the biasing force of the first spring pin 165, which is a spring element, returns the rotational angle positional relationship between the ratchet pawl holding member 141 and the outer ring 110 to its original state.

[0026] Furthermore, when the rotational load state is switched from a state in which the ratchet pawl 142 and the ratchet teeth 147 are engaged with each other due to input of rotational torque in the other direction to the second shaft element 125 to a state in which rotational torque in one direction is input to the second shaft element 125, the outer ring 110 moves circumferentially relative to the ratchet pawl holding member 141 by the amount of backlash S due to the wedge effect and frictional force caused by the cam 132 starting to rotate, as shown in Fig. 8A. Note that Fig. 8A exaggerates the state in which the spline 111 of the outer ring 110 is displaced relative to the spline 143 of the ratchet pawl holding member 141. While the outer ring 110 rotates relative to the ratchet pawl holding member 141, the torque (T2 shown in Fig. 6) acting on the ratchet mechanism due to the elastic deformation of the ratchet pawl 142 and the ratchet teeth 147 that occurs when they are engaged disappears. When the outer ring 110 rotates relative to the ratchet pawl holding member 141 by the amount of backlash S and the spline 111 of the outer ring 110 comes into contact with the spline 122 of the first shaft element 120, as shown in Figure 8B (currently Figure 7B), the cam 132 engages with the outer ring 110 and the inner ring 115, causing a torque T1 to act and transmitting the rotation to the first shaft element 120, and the rotational angle positional relationship between the ratchet pawl holding member 141 and the outer ring 110 returns to its original state due to the spring force of the first spring pin 165, which is a spring element.

[0027] As described above, in the selectable clutch 100 according to this embodiment, rotational play occurs when the rotational load condition changes, so that both the first clutch mechanism 130 and the second clutch mechanism 140 are not simultaneously engaged, and switching can be performed with a light force even when the transmission torque is large.

[0028] In this embodiment, the operating mode of the selectable clutch 100 can be switched by operating the operating mechanism 150 to slide the inner ring 115 in the axial direction. For example, when the operating mode of the selectable clutch 100 is set to the bidirectional lock mode, operating the operating mechanism 150 to slide the inner ring 115 toward one axial end, as shown in Figure 9, the ratchet tooth holding member 146 moves away from the ratchet pawl holding member 141 in the axial direction, and even if rotational torque in the other direction is input to the second shaft element 125, the ratchet pawl 142 and the ratchet teeth 147 do not mesh. In this state, only one-directional rotation of the second shaft element 125 can be transmitted to the first shaft element 120 via the first clutch mechanism 130, i.e., the operating mode of the selectable clutch 100 becomes the one-directional lock mode.

[0029] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design modifications can be made without departing from the present invention as set forth in the claims. In the above embodiment, the first rotation-transmission path and the second rotation-transmission path each include a buffer element and a spring element, but as long as at least a buffer element is provided, the engaging element and the rotating element can move relative to each other in the circumferential direction. In other words, the first rotation-transmission path and the second rotation-transmission path do not need to include a spring element. In addition, in the above embodiment, the first clutch mechanism is configured as a cam-type one-way clutch, but the first clutch mechanism may also be configured as a roller-type one-way clutch in which a cam surface is formed on at least one of the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring, and a roller serving as a locking member is slightly moved to engage with the outer ring and the inner ring by a wedge effect and frictional force.In addition, in the above embodiment, the second clutch mechanism is configured as a ratchet-type one-way clutch in which the ratchet pawl and ratchet teeth are arranged to face each other in the axial direction, but the ratchet pawl and ratchet teeth may also be arranged to face each other in the radial direction.In addition, the second clutch mechanism may also be configured as a dog clutch in which dog teeth arranged at intervals in the circumferential direction on each of the two rotating elements are engaged to transmit rotation between the two rotating elements.

[0030] Furthermore, in the above embodiment, the buffer element is configured by connecting the outer ring and the ratchet pawl holder to the first shaft element to form a splined connection structure based on a clearance fit. However, the buffer element may be configured by connecting the outer ring and the ratchet pawl holder to the first shaft element to form a splined connection structure based on a clearance fit, and connecting the inner ring and the ratchet tooth holder to the second shaft element to form a splined connection structure based on a clearance fit. Furthermore, the configuration of the above embodiment may further include connecting the inner ring and the ratchet tooth holder to the second shaft element to form a splined connection structure based on a clearance fit. In such a configuration, the inner ring and the ratchet tooth holder may be elastically fastened by a second spring pin. Furthermore, the spring element may be formed of a spring member other than a spring pin.

[0031] Furthermore, in the above embodiment, the operating mode is configured to be switchable between a two-way lock mode and a one-way lock mode, but for example, the operating mechanism may be configured to slide axially to separate the cam in the first clutch mechanism from the inner ring, so that the operating mode can be switched, including a two-way free mode in which transmission of rotation in both directions of the input shaft is blocked. Also, in the above embodiment, the operating mechanism is configured to slide the inner ring in the axial direction, but it may also be configured to slide the outer ring in the axial direction. Furthermore, in the above embodiment, the first shaft element is configured to have a cylindrical shaft configured to be case-shaped, but it may also be rod-shaped and arranged to extend along an axis extending parallel to the rotational axis of the selectable clutch. [Explanation of symbols]

[0032] 100 ··· Selectable clutch 110 Outer ring (first rotating element) 111 ··· Spline 112 Insertion hole 115 Inner ring (second rotating element) 116 ··· Spline 117 ... circumferential groove 120 ··· 1st axis element 121 Cylindrical shaft 122 ··· Spline 123... Lid part 125 2nd axis element 126 Cylindrical shaft 127 Flange 128 spline 130 First clutch mechanism 131 ··· Cage ring 132 Cam (locking member) 133 ··· Laura 134 Annular spring (biasing means) 140 Second clutch mechanism 141 Ratchet pawl holding member (first engagement element) 142 Ratchet claw (engagement part) 143 ··· Spline 144 through hole 146 Ratchet tooth retaining member (second engagement element) 147 Ratchet teeth (engagement part) 148 ··· Spline 150...Operating mechanism 151 Selector member 152 Fixing member 160...buffer element 165 First spring pin (spring element) 166 Pin member

Claims

1. A selectable clutch comprising: a first shaft element and a second shaft element, one of which is an input shaft and the other of which is an output shaft; a first clutch mechanism disposed in a first rotation transmission path that transmits rotation in one direction of the input shaft to the output shaft; a second clutch mechanism disposed in a second rotation transmission path that transmits rotation in the other direction of the input shaft to the output shaft; and an operating mechanism that switches the operation of either or both of the first clutch mechanism and the second clutch mechanism, the first clutch mechanism is configured to be able to transmit rotation at any rotation angle by a wedge effect of a locking member that is arranged between a first rotating element and a second rotating element that are coaxially and rotatably relative to each other and that is biased by a biasing means, and by frictional forces between the locking member and the first rotating element and the second rotating element; the second clutch mechanism is configured to be able to transmit rotation at a predetermined rotation angle by meshing an engagement portion of a first engagement element coupled to the first rotating element with an engagement portion of a second engagement element coupled to the second rotating element, A selectable clutch characterized in that each of the first rotation transmission path and the second rotation transmission path has a buffer element that allows either or both of the first engaging element and the second engaging element to move circumferentially relative to the rotating element to which the engaging element is connected.

2. 2. The selectable clutch according to claim 1, further comprising a spring element in each of the first rotation transmission path and the second rotation transmission path, the spring element restoring displacement caused by relative movement between the engaging element and the rotating element.

3. 2. The selectable clutch according to claim 1, wherein the buffer element is configured by connecting the first rotating element and the first engaging element to the first shaft element to form a spline connection structure with a clearance fit, or by connecting the second rotating element and the second engaging element to the second shaft element to form a spline connection structure with a clearance fit.

4. 3. The selectable clutch according to claim 2, wherein the spring element is composed of either or both of a first spring pin that elastically fastens the first rotating element and the first engaging element and a second spring pin that elastically fastens the second rotating element and the second engaging element.

5. the first rotating element and the second rotating element are each composed of an outer ring and an inner ring, the locking member is configured by a plurality of cams provided in a circumferential direction between the outer ring and the inner ring, 2. The selectable clutch according to claim 1, wherein the biasing means biases the plurality of cams so as to contact the outer ring and the inner ring.

6. 2. The selectable clutch according to claim 1, wherein the first engaging element and the second engaging element are arranged opposite each other, one having ratchet teeth as the engaging portion and the other having a ratchet pawl as the engaging portion.

7. the first engaging element and the second engaging element are disposed opposite to each other in the axial direction, 6. The selectable clutch according to claim 5, wherein the operating mechanism is configured to be able to move the first engaging element or the second engaging element in the axial direction.

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