Cam clutch

Abstract

The purpose of the present invention is to provide a cam clutch which has a simple structure, can smoothly switch operation modes while preventing the occurrence of cam engagement, and can achieve low noise and long service life, without causing an increase in size and the number of components. Specifically, the problem can be solved by a configuration in which a transmission member (161) is provided which is in contact with each of a first cam (131a) and a second cam (131b), the first cam (131a) and the second cam (131b) having different meshing directions, and the transmission member (161) is provided so as to be rotatable and movable in the axial direction in a state in which the center of rotation is fixed by a spacer ring (140), and the transmission member (161) is configured so as to be rotatable by rotating the transmission member (161) so that the first cam (131a) and the second cam (131b) move in the axial direction in a state in which the center of rotation is fixed by the spacer ring (140). The first cam (131a) can be tilted by moving the transmission member (161) in the axial direction, and the second cam (131b) can be tilted by moving the transmission member (161) in the axial direction.

Description

Technical Field

[0001] The present invention, for example, relates to a cam clutch, which is constructed to be able to switch between the following action modes, namely: a two-way meshing mode, which can transmit torque in both positive and negative directions between the outer ring and the inner ring; a one-way meshing mode, which can transmit torque in either positive or negative direction between the outer ring and the inner ring; and the two-way idling mode, in which the rotating wheels on the input side of the outer ring and the inner ring idle in both positive and negative directions and cut off the torque transmission between the outer ring and the inner ring. Background Art

[0002] As a clutch that controls transmission and interruption of torque, a two-way clutch that can switch between driving and idling in both the forward rotation direction and the reverse rotation direction is known.

[0003] For example, Patent Document 1 describes a clutch that is configured to apply force to a first wedge and a second wedge in opposite rotational locking directions using a force applying unit, and to switch between two action modes by controlling a retainer that simultaneously holds the first wedge and the second wedge, namely: a one-way meshing mode that can transmit torque only in the forward direction between the outer ring and the inner ring; and a one-way meshing mode that can transmit torque only in the reverse direction between the outer ring and the inner ring.

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-231828 Summary of the invention

[0006] However, "bite" in which all cams are engaged simultaneously may occur in a clutch having the following structure: a clutch in which wedges that engage only in one direction of rotation are arranged in a bilaterally symmetrical shape and the operation mode can be switched by tilting one wedge and the other wedge. That is, in such a clutch, when torque acts on the outer ring or the inner ring, one wedge will immediately tilt to start meshing with the outer ring and the inner ring.

[0007] Although the unloading torque can cause one wedge to tilt in the direction of disengagement and transition to an idling state, at this moment, while the engagement of one wedge is being released, the other wedge will tilt in the direction of engagement and begin to engage with the outer and inner rings, which may result in "bite" in which all cams engage simultaneously.

[0008] In this state, since all the sprags are engaged with a high surface pressure, a large force is required to change the posture of the sprags when switching the clutch operation mode, which may cause damage to the engagement surfaces of the sprags relative to the outer ring and the inner ring, or the track surfaces of the outer ring and the inner ring, shortening the life of the clutch.

[0009] To address this problem, the above-mentioned two-way clutch is constructed to prevent meshing from occurring, i.e., the first wedge block and the second wedge block are arranged in parallel on a common retainer in a manner such that the rotational locking direction is in the opposite direction, and while the first wedge block is urged in the anti-locking direction, the second wedge block is maintained in a state where it is urged in the locking direction.

[0010] However, the above-mentioned two-way clutch is constructed so that when the action mode is switched, all the wedges of the first wedge and the second wedge are forced to fall down at the same time by controlling the retainer. Therefore, the following modes cannot be realized in the above-mentioned two-way clutch, namely: a two-way meshing mode that can transmit torque in both positive and negative directions between the outer ring and the inner ring; and a two-way idling mode that makes the rotating wheels on the input side of the outer ring and the inner ring idling in both positive and negative directions and cuts off the torque transmission between the outer ring and the inner ring. In addition, since a sliding torque is generated by contacting the inner ring and the outer ring by either the first wedge or the second wedge with the inner ring and the outer ring during idling, the torque during idling will increase. In addition, in the structure of controlling the retainer by applying a load to the retainer through a gear mechanism from a load applying device, the gear connected to the retainer will form a rotational resistance, which will also increase the torque during idling.

[0011] The present invention is based on the above situation, and the technical problem to be solved is to provide a cam clutch that is not accompanied by enlargement and increase in the number of parts, has a simple structure, can smoothly switch the action mode while preventing the cam from biting, and can achieve low noise and long life.

[0012] The present invention is a cam clutch comprising: an outer ring and an inner ring, which are configured to be able to rotate relative to each other on the same axis; a plurality of cams, which are arranged between the outer ring and the inner ring; and a spacer ring, which holds the plurality of cams in the circumferential direction. The problem can be solved by the following contents, namely, the plurality of cams include a first cam and a second cam, which have different meshing directions relative to the outer ring and the inner ring, the first cam and the second cam are configured in pairs, and a transmission component is provided, which is configured to contact each of the paired first cam and the second cam, and can rotate and move in the axial direction in a state where the rotation center is fixed by the spacer ring, and the transmission component is constructed so that the first cam can be tilted between a meshing standby state and a non-contact state with the outer ring or the inner ring by rotation, and is constructed so that the second cam can be tilted between a meshing standby state and a non-contact state with the outer ring or the inner ring by moving in the axial direction.

[0013] According to the invention involved in the first technical solution, since the tilting of the first cam and the tilting of the second cam are independently performed by different actions of the transmission member, it is possible to configure a simple structure to switch the action mode of the cam clutch between the three action modes of the two-way meshing mode, the one-way meshing mode and the two-way idling mode. In addition, since the switching of the action mode between the two-way meshing mode and the two-way idling mode is to perform the tilting of the first cam and the tilting of the second cam in stages, the number of cams rotating at the same time is reduced. As a result, when the torque load is applied, the release torque required to release the meshing of the cam can be reduced, so that the engagement surface of the cam, the track surface of the outer ring and the track surface of the inner ring can be achieved without damaging the engagement surface of the cam, the track surface of the outer ring and the track surface of the inner ring, thereby achieving a long life. In addition, since the tilting of the first cam is performed by rotating the transmission member, and the tilting of the second cam is performed only by the axial movement of the transmission member, the axial movable range of the transmission member can be reduced compared to the structure in which the tilting of the cam is performed only by the axial movement of the action mode switching unit, and the increase in the axial dimension can be avoided.

[0014] In addition, since all cams are in a state of no contact with the outer ring or the inner ring when the action mode is the bidirectional idling mode, no sliding torque is generated during idling. Therefore, at this point, the engaging surface of the cam, the track surface of the outer ring, and the track surface of the inner ring will not be damaged, thereby achieving long service life and reducing noise.

[0015] According to the invention involved in the second technical solution, when a torque acts on the outer ring or the inner ring, the first cam that tilts in a manner that meshes with the outer ring and the inner ring is linked, so that the second cam that usually maintains the meshing standby state can be tilted in the meshing release direction, and the engaging surface of the second cam can be separated from the track surface of the outer ring and / or the track surface of the inner ring. Therefore, even if the second cam tilts in the meshing direction when the torque is unloaded, the second cam can be prevented from meshing with the outer ring and the inner ring until the meshing of the first cam is released. Therefore, smooth operation can be achieved and high responsiveness can be obtained. In addition, by suppressing the occurrence of biting, a large drive source is not required as a drive source for moving the transmission component in the axial direction, thereby achieving energy saving and miniaturization.

[0016] According to the invention involved in Technical Solution 3, there is no need to provide an additional driving source for rotating the transmission member. The rotation and axial movement of the transmission member can be achieved simply by moving the selector in the axial direction, thereby avoiding the complexity and enlargement of the structure of the cam clutch.

[0017] According to the invention involved in Technical Solution 4, since the transmission component has the function of tilting the first cam and the function of tilting the second cam, other components that help switch the action mode can also become a simple structure, thereby achieving structural simplification and facilitating manufacturing.

[0018] According to the invention of claim 5, the mechanism for rotating and axially moving the transmission member does not generate rotation resistance, and thus the torque during idling can be reduced.

[0019] According to the invention involved in claim 6, since the axial size of the cam clutch can be reduced and a common component can be used as a biasing unit for all cams, the number of parts can be reduced and the structure can be simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is an exploded perspective view showing the structure of an example of the cam clutch of the present invention.

[0021] Figure 2 Yes means Figure 1 A cross-sectional view of a portion of the cam clutch shown is taken along a plane along the rotation axis.

[0022] Figure 3 yes Figure 1 The cam clutch is shown in a cross-sectional view cut along a plane perpendicular to the rotation axis.

[0023] Figure 4 The structure of the first cam is shown, (a) is a perspective view, and (b) is an end view of one end side.

[0024] Figure 5 The structure of the second cam is shown, (a) is an end view of one end side, and (b) is a perspective view.

[0025] Figure 6 It is a cross-sectional perspective view showing a part of the spacer ring.

[0026] Figure 7 It is a side view showing the structure of the transmission member.

[0027] Figure 8 express Figure 7 The structure of the transmission component shown in FIG. 1 is an end view of one end side, and (b) is an end view of the other end side.

[0028] Fig. 9 Yes Figure 1 The cam clutch shown is a plan view from one axial end side with part of it omitted.

[0029] Fig.10 It is a schematic representation Figure 1 The illustrated cam clutch is a side view showing a state of the cam clutch when the operation mode of the cam clutch is the bidirectional meshing mode.

[0030] Fig.11A It is a diagram showing a contact state between a cam contact portion of a transmission member and a step portion of a cam when the first cam and the second cam are in a meshing standby state in a bidirectional meshing mode.

[0031] Fig. 11B This is a diagram schematically showing the positional relationship between the cams and the transmission member when the first cam and the second cam are in the engagement standby state in the bidirectional engagement mode, as viewed from one axial end side.

[0032] Fig.12 It is a schematic representation Figure 1 The illustrated cam clutch is a side view showing a state of the cam clutch when the operation mode of the cam clutch is the one-way meshing mode.

[0033] Fig.13A This is a diagram schematically showing the positional relationship between the cam and the transmission member when the second cam is in the engagement standby state in the one-way engagement mode, as viewed from one axial end side.

[0034] Fig. 13B This is a diagram showing a contact state between the cam contact portion of the transmission member and the step portion of the cam when the second cam is in the engagement standby state in the one-way meshing mode.

[0035] Fig.14 It is a schematic representation Figure 1 The illustrated cam clutch is a side view showing a state of the cam clutch when the operation mode of the cam clutch is the bidirectional idling mode.

[0036] Fig.15 Yes means Figure 1 The diagram shows a state of abutment between the cam abutment portion of the transmission member and the step portion of the cam when the operation mode of the cam clutch is the bidirectional idling mode.

[0037] Explanation of symbols

[0038] 100-cam clutch; 110-outer ring; 111-track surface; 120-inner ring; 121-track surface; 130-cam mechanism; 131-cam; 131a-first cam; 131b-second cam; 132-cam pair; 133-outer ring side engagement surface; 134-inner ring side engagement surface; 135-hoop spring mounting groove; 136-step portion; 140-spacer ring; 141-small diameter cylindrical portion; 142-opening portion; 143-column portion; 144a-first cam retainer Part; 144b-the second cam holding part; 145-the flange; 146-the through hole; 147-the large diameter cylindrical part; 148-the transmission component accommodating part; 150-the force adding unit; 160-the action mode switching mechanism; 161-the transmission component; 162-the base part; 163-the load applying part; 164-the rotational force acting surface; 165-the guide surface; 166-the cam abutting part; 167-the cam pressing surface; 168-the cam acting surface; 168a-one end edge; 170-the selector. DETAILED DESCRIPTION

[0039] like Figure 1 As shown, the cam clutch 100 of the present invention includes an outer ring 110 , an inner ring 120 , a cam mechanism 130 , and an operation mode switching mechanism 160 .

[0040] like Figure 2 and Figure 3 As shown, in the assembled state of the cam clutch 100 , the outer ring 110 and the inner ring 120 are relatively rotatably arranged on the same rotation axis X, and the raceway surface 111 of the outer ring 110 and the raceway surface 121 of the inner ring 120 are opposite to each other.

[0041] like Figure 1 As shown, the cam mechanism 130 includes: a plurality of cams 131; a spacer ring 140 for holding the plurality of cams 131 at intervals in the circumferential direction; and a biasing unit 150 for biasing each of the plurality of cams 131 in the meshing direction so as to contact the outer ring 110 and the inner ring 120.

[0042] like Figure 3 As shown, each of the plurality of cams 131 includes a first cam 131a and a second cam 131b having different meshing directions with respect to the outer ring 110 and the inner ring 120, the first cam 131a and the second cam 131b form a pair, and the plurality of cam pairs 132 are arranged on the same circumference at a predetermined interval in the circumferential direction. Hereinafter, except for the case where the first cam 131a and the second cam 131b are specifically mentioned, they are simply referred to as cams 131.

[0043] By arranging the plurality of cams 131 on the same circumference, the axial size of the cam clutch 100 can be reduced, and a common component can be used as the urging unit 150 for all cams 131 , thereby reducing the number of parts and simplifying the structure.

[0044] Although in this embodiment, ten cam pairs 132 are arranged at equal intervals in the circumferential direction, the number of cam pairs 132 is not particularly limited and can be appropriately changed according to the target torque capacity. In addition, the arrangement intervals of the cam pairs 132 may not be equal intervals.

[0045] like Figure 4 As shown in (a) and (b), the first cam 131a has: an outer ring side engaging surface 133, which is formed into a curved shape including an arc-shaped portion; and an inner ring side engaging surface 134, which is formed into an arc shape with a larger curvature radius than the outer ring side engaging surface 133, and is configured so that by turning the outer ring 110 in the forward rotation direction ( Figure 3 counterclockwise in the middle) or by rotating the inner ring 120 in the reverse direction ( Figure 3 The outer ring 110 and the inner ring 120 can be engaged with each other by rotating in the clockwise direction.

[0046] In this embodiment, as the urging unit 150, for example, an annular hoop spring is used, and a hoop spring installation groove 135 extending in the circumferential direction is formed on the outer ring side engagement surface 133 of the first cam 131a. The hoop spring installation groove 135 is configured so that by installing the hoop spring, Figure 3 In this case, a counterclockwise rotation torque can be applied to the first cam 131a.

[0047] Furthermore, a step portion 136 extending axially outward is provided on an end surface on one axial end side of the first cam 131 a .

[0048] In the present embodiment, the step portion 136 is configured to form a planar shape in which the outer ring side portion on one end of the first cam 131a is cut off by two planes, and the two planes intersect with each other at an obtuse apex angle and are perpendicular to the cam end face. The top of the step portion 136 is formed on the outer ring side engagement surface 133 side relative to the curvature center C1 of the inner ring side engagement surface 134, and is formed on the side (ie, the side) where the second cam 131b of the pair is located relative to the normal line H on the tangent point P between the first cam 131a and the track surface 121 of the inner ring 120. Figure 4 (b) on the right side) of the displacement position.

[0049] The second cam 131 b is configured to mesh with the outer ring 110 and the inner ring 120 when the outer ring 110 is rotated in the reverse direction or the inner ring 120 is rotated in the forward direction.

[0050] like Figure 5 As shown in (a) and (b), the second cam 131b involved in this embodiment has the same structure as the first cam 131a, and is configured so that the first cam 131a and the second cam 131b are mirror images of each other. That is, the second cam 131b has an outer peripheral contour shape that is the first cam 131a reversed inside and outside, and the top of the step portion 136 is formed on the outer ring side engagement surface 133 side relative to the curvature center C2 of the inner ring side engagement surface 134, and is formed on the side of the first cam 131a that is paired with the normal line H relative to the tangent point P between the second cam 131b and the track surface 121 of the inner ring 120 ( Figure 5 (a) on the left side) of the displacement position.

[0051] The hoop spring installation groove 135 is configured so that, by installing the hoop spring, Figure 3 In this case, a clockwise rotation torque can be applied to the second cam 131b.

[0052] like Figure 6 As shown, the spacer ring 140 includes: a small diameter cylindrical portion 141; a flange portion 145, which is formed to protrude radially outward over the entire circumference on an axial end portion of the small diameter cylindrical portion 141; and a large diameter cylindrical portion 147, which is formed so that, on an axial end face of the flange portion 145, the inner circumferential surface is connected to the inner circumferential surface of the small diameter cylindrical portion 141.

[0053] The small diameter cylindrical portion 141 is provided with openings 142 arranged at equal intervals in the circumferential direction. Each opening 142 is divided in the circumferential direction by a column portion 143 extending in the axial direction, and the space portion on the forward rotation direction side is constituted as the first cam holding portion 144a, while the space portion on the reverse rotation direction side is constituted as the second cam holding portion 144b. The circumferential dimensions of the first cam holding portion 144a and the second cam holding portion 144b are configured to be smaller than the maximum outer diameter of the cam 131.

[0054] A transmission component accommodating portion 148 is formed on the outer peripheral surface of the large diameter cylindrical portion 147. The transmission component accommodating portion 148 is formed by forming a through hole 146 extending in the axial direction at a circumferential position corresponding to the column portion 143 of each opening portion 142 on the flange portion 145.

[0055] The first cam 131a and the second cam 131b are inserted into the corresponding first cam retaining portion 144a and the second cam retaining portion 144b from the radially outer side, and are configured so that the inner ring side engaging surface 134 protrudes radially inward from the inner circumferential surface of the spacer ring 140, and are retained on the spacer ring 140 by installing a hoop spring.

[0056] The cam mechanism 130 is configured such that the small-diameter cylindrical portion 141 of the spacer ring 140 is inserted into the annular space between the track surface 111 of the outer ring 110 and the track surface 121 of the inner ring 120, thereby arranging a plurality of cams 131 in the annular space and the spacer ring 140 being rotatable independently of the outer ring 110 and the inner ring 120. By arranging the spacer ring 140 to be rotatable independently of the outer ring 110 and the inner ring 120, the torque during idling can be reduced.

[0057] Moreover, the cam clutch 100 involved in the present embodiment has an action mode switching mechanism 160, which can switch between the following three action modes, namely: a two-way meshing mode, which can transmit torque in both positive and negative directions between the outer ring 110 and the inner ring 120; a one-way meshing mode, which can transmit torque in either positive or negative directions between the outer ring 110 and the inner ring 120; and a two-way idling mode, in which the rotating wheels on the input side of the outer ring 110 and the inner ring 120 idle in both positive and negative directions, and the torque transmission between the outer ring 110 and the inner ring 120 is cut off.

[0058] like Figures 1 to 3 As shown, the action mode switching mechanism 160 includes: a plurality of transmission components 161, which are provided corresponding to each of the plurality of cam pairs 132 and are configured to tilt the paired first cam 131a and second cam 131b, respectively; and a selector 170, which enables the plurality of transmission components 161 to move simultaneously.

[0059] The transmission component 161 is configured to be able to tilt the first cam 131a between an engaged standby state and a non-contact state with the outer ring 110 or the inner ring 120 by rotating around an axis extending along the rotation axis X of the cam clutch 100, and is configured to be able to tilt the second cam 131b between an engaged standby state and a non-contact state with the outer ring 110 or the inner ring 120 by moving in the axial direction.

[0060] like Figure 7 As shown, the transmission component 161 involved in this embodiment has: a cylindrical base portion 162; a load applying portion 163, which is formed to extend axially outward at one axial end side of the base portion 162; and a cam abutment portion 166, which is formed to extend axially outward at the other axial end side of the base portion 162.

[0061] Also like Figure 8 As shown in (a), the load applying portion 163 is formed into a columnar shape with a roughly semicircular cross-section, for example, having: a flat rotational force application surface 164, located on a plane perpendicular to an end surface of the base portion 162 containing the central axis O; and a guide surface 165, which is continuous with the rotational force application surface 164 and extends inclined toward the outer peripheral surface side as it moves toward one axial end side.

[0062] Also like Figure 8 As shown in (b), the cam contact portion 166 is formed to be a columnar shape having a substantially semicircular cross section at a position on the opposite side of the load applying portion 163 sandwiching the central axis in a plan view, and has, for example, a flat cam pressing surface 167 located on a plane perpendicular to the other end surface of the base portion 162 including the central axis O and inclined in the rotation direction relative to the rotation force acting surface 164; and a cam acting surface 168 formed continuously on the axial one end side of the cam pressing surface 167 for tilting the cam 131. The cam acting surface 168 is formed so that, while being inclined in a direction away from the cam pressing surface 167 toward the axial one end side, one end edge 168a extends along the inclination direction of the rotation force acting surface 164 relative to the cam pressing surface 167.

[0063] According to the transmission component 161 of this structure, since the transmission component 161 can have the function of tilting the first cam 131a and the function of tilting the second cam 131b, and other components that help switch the action mode of the cam clutch 100 can also be simple structures, the structure can be simplified and it can be easy to manufacture.

[0064] The transfer member 161 is configured to be accommodated in the transfer member accommodation portion 148 with the base portion 162 inserted into the through hole 146 on the spacer ring 140 , and to be rotatable and axially movable with the rotation center fixed by the spacer ring 140 .

[0065] The transmission member 161 is configured such that, when the operation mode of the cam clutch 100 is the two-way meshing mode, in other words, when the first cam 131a and the second cam 131b are each in the meshing standby state, the cam pressing surface 167 of the cam contact portion 166 contacts each of the step portion 136 of the first cam 131a and the step portion 136 of the second cam 131b, and rotates as the first cam 131a tilts in the meshing direction, causing the second cam 131b to tilt in the meshing release direction. Therefore, when a torque acts on the outer ring 110 or the inner ring 120, the second cam 131b, which is usually maintained in the meshing standby state, can be tilted in the meshing release direction in conjunction with the first cam 131a tilting in a manner meshing with the outer ring 110 and the inner ring 120. Thus, the outer ring side engagement surface 133 of the second cam 131b can be separated from the track surface 111 of the outer ring 110, and even if the second cam 131b tilts in the meshing direction when the torque is unloaded, the second cam 131b can be prevented from meshing with the outer ring 110 and the inner ring 120 until the meshing of the first cam 131a is released. Therefore, smooth operation can be achieved and high responsiveness can be obtained. In addition, by suppressing the occurrence of biting, it is not necessary to use a large drive source as a drive source for moving the transmission member 161 in the axial direction, thereby achieving energy saving and miniaturization.

[0066] The selector 170 according to the present embodiment is formed of, for example, an annular member, and is externally fitted to the large-diameter cylindrical portion 147 of the spacer ring 140 so as to be movable in the axial direction.

[0067] In the cam clutch 100, when the first cam 131a and the second cam 131b are in the meshing standby state, Fig. 9 As shown in FIG. 1 , the transmission member 161 is in a state where a portion of the load applying portion 163 protrudes radially outward from the opening edge of the transmission member accommodating portion 148. Therefore, the selector 170 is configured to rotate the transmission member 161 by engaging with the transmission member 161. By adopting such a configuration, it is not necessary to separately provide a driving source for rotating the transmission member 161. The rotation and axial movement of the transmission member 161 can be achieved by simply moving the selector 170 in the axial direction, thereby avoiding the complication and enlargement of the structure of the cam clutch 100.

[0068] The selector 170 may be moved in the axial direction manually or by a driver (not shown) or the like.

[0069] Next, the operation of the above-mentioned cam clutch 100 will be described.

[0070] First, if Fig.10As shown, when the selector 170 is fixed in the first fixed position and is in a non-contact state with the transmission component 161, since a torque acts on the outer ring 110 or the inner ring 120, the first cam 131a and the second cam 131b maintain an engagement standby state so as to immediately start engaging the outer ring 110 and the inner ring 120. Therefore, the action mode of the cam clutch 100 is a bidirectional engagement mode that can transmit torque in both positive and negative directions between the outer ring 110 and the inner ring 120.

[0071] When the first cam 131a and the second cam 131b are in the meshing standby state, Fig.11A As shown, the cam pressing surface 167 of the cam contact portion 166 on the transmission member 161 contacts both the step portion 136 of the first cam 131a and the step portion 136 of the second cam 131b. Therefore, when a torque is applied to rotate the first cam 131a in a manner that tilts in the meshing direction, the transmission member 161 rotates along with the tilting of the first cam 131a. As a result, the second cam 131b rotates in a manner that tilts in the meshing release direction, and the outer ring side engaging surface 133 of the second cam 131b leaves the track surface 111 of the outer ring 110. When the torque is unloaded, the first cam 131a rotates in a manner that tilts in the meshing release direction and transitions to the meshing standby state. At this moment, although the second cam 131b rotates in a manner tilting toward the meshing direction, when the first cam 131a meshes, the outer ring side engaging surface 133 of the second cam 131b will leave the track surface 111 of the outer ring 110, so that the second cam 131b can be prevented from meshing with the outer ring 110 and the inner ring 120 until the meshing of the first cam 131a is released.

[0072] In addition, when the second cam 131b rotates in a manner tilting in the meshing direction, the transmission member 161 also rotates with the tilting of the second cam 131b, and rotates the first cam 131a in a manner tilting in the meshing release direction, thereby making it possible to separate the outer ring side engagement surface 133 of the first cam 131a from the track surface 111 of the outer ring 110. When the torque is unloaded and the second cam 131b rotates in a manner tilting in the meshing release direction and transitions to the meshing standby state, the first cam 131a can be prevented from meshing with the outer ring 110 and the inner ring 120 until the meshing of the second cam 131b is released.

[0073] In this way, by interlocking the rotational motions of the first cam 131 a and the second cam 131 b using the transmission member 161 , smooth motion can be achieved without causing biting.

[0074] When the operation mode of the cam clutch 100 is the two-way meshing mode and the first cam 131a and the second cam 131b are in the meshing standby state, Fig. 11BAs shown, the rotation force acting surface 164 of the load applying portion 163 on the transmission member 161 is inclined in the rotation direction relative to the cam pressing surface 167, and a portion thereof is in a state of protruding radially outward from the opening edge of the transmission member accommodating portion 148 (see Fig. 9 ).

[0075] like Fig.12 As shown in FIG. 1 , when the selector 170 is moved toward the other end side of the axial direction and the selector 170 is fixed at the second fixed position, as shown in FIG. Fig.13A As shown, the selector 170 engages with the transmission component 161 and causes the transmission component 161 to rotate. Fig. 13B As shown, the step portion 136 of the first cam 131a is pressed by the cam pressing surface 167 of the cam contact portion 166 on the transmission member 161, and the first cam 131a rotates in a manner of tilting in the meshing release direction. As a result, the outer ring side engagement surface 133 of the first cam 131a is maintained in a state of being separated from the track surface 111 of the outer ring 110, and the operation mode of the cam clutch 100 is switched to the one-way meshing mode. In the one-way meshing mode involved in this embodiment, for example, when the inner ring 120 is rotated in the forward direction, the second cam 131b can engage with the outer ring 110 and the inner ring 120 to transmit torque.

[0076] In addition, in the cam clutch 100, as shown in FIG. Fig.14 As shown in FIG. 1 , when the selector 170 is moved from the second fixed position toward the other axial end side and fixed at the third fixed position, as shown in FIG. Fig.15 As shown, the transmission member 161 is pressed by the selector 170 and moves in the axial direction, whereby the second cam 131b is rotated in a manner of tilting in the meshing release direction by the action of the cam action surface 168 on the cam contact portion 166, and the outer ring side engagement surface 133 of the second cam 131b is maintained in a state where the outer ring side engagement surface 133 is separated from the track surface 111 of the outer ring 110. The first cam 131a is maintained in a state where the outer ring side engagement surface 133 is separated from the track surface 111 of the outer ring 110. As a result, when the rotating wheel on the input side rotates in either the forward or reverse direction, the rotating wheel on the input side will idle, and the action mode of the cam clutch 100 is switched to a two-way idle mode that cuts off the torque transmission between the outer ring 110 and the inner ring 120.

[0077] Moreover, according to the above-mentioned cam clutch 100, since the tilting of the first cam 131a and the tilting of the second cam 131b are performed independently through different actions of the transmission component 161, it is possible to switch the action mode of the cam clutch 100 between three action modes of a two-way meshing mode, a one-way meshing mode and a two-way idling mode with a simple structure.

[0078] Furthermore, since the switching of the operation mode between the two-way meshing mode and the two-way idling mode is performed by tilting the first cam 131a and the second cam 131b in stages, the number of cams 131 rotating at the same time is reduced. As a result, the release torque required to release the meshing of the cam 131 can be reduced under torque load, so that the outer ring side engagement surface 133 and the inner ring side engagement surface 134 of the cam 131, the track surface 111 of the outer ring 110, and the track surface 121 of the inner ring 120 can be prevented from being damaged while achieving smooth operation, thereby achieving a longer life.

[0079] In addition, since the first cam 131a is tilted by rotating the transmission component 161, and the second cam 131b is tilted only by the axial movement of the transmission component 161, the axial movable range of the transmission component 161 can be reduced compared to a structure in which the cam 131 is tilted only by the axial movement of the action mode switching unit, thereby avoiding an increase in the axial dimension.

[0080] In addition, since all cams 131 are in a state of no contact with the outer ring 110 or the inner ring 120 when the action mode is the bidirectional idling mode, no sliding torque will be generated during idling. Therefore, at this point, the outer ring side engaging surface 133 and the inner ring side engaging surface 134 of the cam 131 and the track surface 111 of the outer ring 110 and the track surface 121 of the inner ring 120 will not be damaged, thereby achieving long life and reducing noise.

[0081] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and various design changes can be made without departing from the present invention described in the technical claims.

[0082] For example, although in the above-mentioned embodiment, the transmission component is constructed to have a load applying portion, and the transmission component is rotated by utilizing the engagement of the selector composed of an annular body, the load applying portion is formed so that when the cam pressing surface is in contact with each of the first cam and the second cam, the rotational force acting surface and the pressing surface are inclined in the rotation direction, and are constructed to protrude from the opening edge of the transmission component accommodating portion, it is also possible to provide an inclined surface portion on the selector, and to configure the inclined surface portion so that the transmission component is rotated by moving the selector in the axial direction.

[0083] Furthermore, in the above-described embodiment, the rotation force acting surface and the cam pressing surface of the transmission member are configured as flat surfaces, but they are not necessarily required to be flat surfaces.

[0084] Furthermore, although the cam is configured to have a step portion on one axial end surface that contacts the cam contact portion of the transmission member, for example, a pin member or the like may be provided to receive the load from the transmission member.

[0085] In addition, although the above-mentioned embodiment is configured such that the cam on the positive rotation direction side of the cam pair is the first cam and the cam pressing surface of the transmission member is inclined to the load application surface so that the cam on the positive rotation direction side of the cam pair is rotated by the rotation of the transmission member, it is also possible to configure such that the cam on the reverse rotation direction side of the cam pair is the first cam and the cam pressing surface is inclined to the load application surface so that the cam on the reverse rotation direction side is rotated by the rotation of the transmission member. In the case of such a configuration, when the outer ring is rotated in the positive rotation direction or the inner ring is rotated in the reverse rotation direction, the cam on the positive rotation direction side of the cam pair is engaged with the outer ring and the inner ring, so that torque can be transmitted in the opposite direction to the above-mentioned embodiment.

[0086] Furthermore, in the above-described embodiment, a configuration has been described in which the cam is tilted so as to be separated from the outer ring. However, the cam clutch of the present invention may be configured so as to be tilted so as to be separated from the inner ring.

[0087] In addition, although the above-mentioned embodiment describes a configuration with a biasing unit, it is also possible to configure without a biasing unit. In addition, the biasing unit is not limited to a hoop spring, and may be composed of a plurality of elastic bodies such as leaf springs or torsion springs.

Claims

1. A cam clutch comprising: an outer ring and an inner ring, which are arranged to be relatively rotatable on the same axis; a plurality of cams, which are arranged between the outer ring and the inner ring; and a spacer ring, which holds the plurality of cams in a circumferential direction, characterized in that: The plurality of cams include a first cam and a second cam whose meshing directions with respect to the outer ring and the inner ring are different from each other, and the first cam and the second cam are arranged in a pair. A transmission member is provided, the transmission member being arranged to contact each of the first cam and the second cam forming a pair, and being rotatable and movable in the axial direction in a state where the rotation center is fixed by the spacer ring, The transmission component is configured to enable the first cam to tilt between an engagement standby state and a state of non-contact with the outer ring or the inner ring by rotating, and is configured to enable the second cam to tilt between an engagement standby state and a state of non-contact with the outer ring or the inner ring by moving in the axial direction.

2. The cam clutch according to claim 1, characterized in that: The transmission member is configured to rotate as the first cam tilts in the meshing direction and tilt the second cam in the meshing release direction when the first cam and the second cam are each in the meshing standby state.

3. The cam clutch according to claim 1, characterized in that: A selector is provided so as to be movable in the axial direction relative to the spacer ring and used to make the transmission member movable, The selector is configured to rotate the transmission member by engaging with the transmission member.

4. The cam clutch according to claim 1, characterized in that: The transmission member comprises: a cylindrical base portion; a load applying portion provided at one axial end side of the base portion; and a cam contact portion provided at the other axial end side of the base portion. The load applying portion has a rotation force acting surface, The cam abutment portion has a cam pressing surface inclined in the rotation direction relative to the rotation force application surface and a cam action surface that causes the cam to tilt. The cam action surface is formed so that while it is inclined in a direction away from the cam pressing surface toward one axial end side, one end edge extends along the inclination direction of the rotation force application surface relative to the cam pressing surface.

5. The cam clutch according to claim 1, characterized in that: The spacer ring is configured to be rotatable independently of the outer ring and the inner ring.

6. The cam clutch according to claim 1, characterized in that: The first cam and the second cam are arranged on the same circumference. The invention further comprises a biasing unit for biasing the first cam and the second cam so as to put the first cam and the second cam into a meshing standby state.

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