JP6460385B2 - Driving force transmission device - Google Patents

Description

  The present invention relates to a driving force transmission device capable of switching transmission / disconnection of a rotational driving force between a first shaft body and a second shaft body.

  The rotation transmission device described in Patent Document 1 below includes an electromagnetic clutch and a roller clutch as a two-way clutch. In this roller clutch, a pair of opposed rollers and a spring that urges the rollers away from each other are interposed in each of wedge spaces formed by the inner periphery of the outer ring and the outer periphery of the inner ring. The pair of rollers is supported by two holders, a control holder and a rotary holder. A ball cam structure is provided between the opposing surfaces of the flange of the control cage and the flange of the rotary cage so that the control cage and the rotary cage can be rotated relative to each other along with the axial movement of the control cage. . By moving the control cage in the axial direction by energization / power cutoff of the electromagnetic clutch, the control cage and the rotary cage rotate relative to each other. As a result, the pair of rollers is switched between an engaged state and a disengaged state with the inner periphery of the outer ring and the outer periphery of the inner ring.

JP 2013-92191 A

  However, in the rotation transmission device described in Patent Document 1, since the ball cam structure is integrated with the rotation cage, the shape of the rotation cage is complicated, which increases the cost. Further, since a high contact pressure (high hardness) is required for the sliding surface between the ball and the cam, a heat treatment or the like is required, which also causes an increase in cost. Although the cam can be formed using ceramics instead of the steel material, there is a risk that the cost increases with the adoption of ceramics. Therefore, it is desired to adopt a new structure replacing the ball cam structure as a mechanism for switching the engagement / release of the roller clutch.

The inventors of the present application employ a two-way clutch including a first and a second retainer, a guide member, and an electromagnetic clutch that are rotatably provided as a two-way clutch included in the driving force transmission device. I am considering that.
The electromagnetic clutch includes an armature connected to the guide member and movable in the axial direction, and a rotor facing the armature in the axial direction. In the engaged state of the two-way clutch, the electromagnetic clutch is turned off. At this time, the guide member is disposed at the initial position. On the other hand, when the two-way clutch is released, the electromagnetic clutch is turned on. When the electromagnetic clutch is switched to the on state, the armature is attracted to the one side in the axial direction by the electromagnetic clutch, and accordingly, the guide member is pulled in to the one side in the axial direction and arranged at the retracted position.

As the guide member moves in one axial direction, the first retainer rotates toward the other circumferential direction and presses one roller toward the other circumferential direction. Further, as the guide member moves in one axial direction, the second retainer rotates toward one circumferential direction and presses the other roller toward one circumferential direction.
By the way, the magnitude of the attractive force of the electromagnetic clutch (the force with which the electromagnetic clutch pulls the guide member) is inversely proportional to the square of the distance between the armature and the rotor. That is, the attractive force by the electromagnetic clutch at the initial stage of retracting the guide member by the electromagnetic clutch is small. Therefore, it is desired to increase the rotational torque that acts on the first and second cages at the initial pull-in time by the electromagnetic clutch.

  Therefore, an object of the present invention is to maintain a high rotational torque acting on the first and second cages at the initial pull-in time by the electromagnetic clutch, thereby favorably switching transmission / disconnection of the rotational driving force. It is providing the driving force transmission device which can be performed.

In order to achieve the above object, the invention according to claim 1 is directed to transmitting rotational driving force between the first shaft body (2) and the second shaft body (3) arranged coaxially with each other. A driving force transmission device (1, 201) capable of switching between cutting and cutting, wherein the inner ring (4) is coaxially connected to the first shaft body, and is coaxially connected to the second shaft body, A cylindrical outer ring (5) provided on the inner ring so as to be relatively rotatable, and a wedge space (29) formed by the outer circumference of the inner ring and the inner circumference of the outer ring are arranged side by side in the circumferential direction (Y). A roller pair (23) composed of a first roller (23a) on one side (Y1) in the direction and a second roller (23b) on the other side (Y2) in the circumferential direction, and a first for holding the roller pair And a second retainer (32) for retaining the roller pair, the first retainer. A second cage that is rotatably provided to the cage, a first sliding contact surface (53) that is slidably in contact with the first cage from one side in the circumferential direction, and a circumferential direction with respect to the second cage A guide member (26) having a second slidable contact surface (54) slidably contacting from the other side and provided so as to be movable in the axial direction (X), the guide member moving toward one axial direction Accordingly, a guide member for rotating the first retainer toward the other circumferential direction and a second retainer for rotating toward the other circumferential direction, and an armature (71 connected to the guide member) And an electromagnetic clutch (7) having an armature that is movable in the axial direction by driving the armature, and the first retainer is mounted on the first sliding contact surface. The first slidable contact surface (38) to be slidably contacted, and the second retainer is A second of the sliding surface which is in sliding contact with the contact surface (42), said first sliding surface and the first of the sliding contact surface, the guide member is said first retainer On the other hand, by moving to one side in the axial direction, a tangent line at the first contact point (PC1), which is a contact point between the first sliding contact surface and the first sliding contact surface, and the axial direction are The first contact angle (θ ₁ ), which is an angle formed, is provided so as to increase, and / or the second sliding contact surface and the second sliding contact surface are configured such that the guide member is the first contact angle. A tangent line at a second contact point (PC2), which is a contact point between the second sliding contact surface and the second sliding contact surface, by moving to one side in the axial direction with respect to the cage of 2; Provided is a driving force transmission device provided so that a _second contact angle (θ ₂ ), which is an angle formed by the axial direction, is enlarged.

The numbers in parentheses indicate corresponding components in the embodiments described later, but this does not mean that the present invention should be limited to those embodiments. The same applies hereinafter.
According to a second aspect of the present invention, at least one of the first and second slidable contact surfaces has a first curved portion (101, 102) whose cross-sectional shape along the axial direction is curved. The driving force transmission device according to claim 1.

The invention according to claim 3 is the invention according to claim 2, wherein the at least one sliding contact surface has a second curved portion (101, 102) having a convexly curved cross-sectional shape along the radial direction (Z). It is a driving force transmission device.
The invention according to claim 4, of the pre-Symbol first and second of the sliding contact surface, wherein at least one of Hisuri contact surface that is in sliding contact with the sliding contact surface, the relates axial first bay The driving force transmission device (1) according to claim 2 or 3, wherein the driving force transmission device (1) is configured by a concave curved surface (103, 104) that is concavely curved with a curvature smaller than that of the curved portion.

The invention according to claim 5, among the pre-Symbol first and second of the sliding contact surface, wherein at least one of Hisuri contact surface that is in sliding contact with the sliding contact surface, the relates axial first bay It is composed of a concave curved surface (203, 204) that is concavely curved with a smaller curvature than the curved portion, and a flat inclined surface (211, 212) that is continuous on the other side in the axial direction with respect to the concave curved surface. A driving force transmission device (201) according to claim 2 or 3.

  According to the first aspect of the present invention, the first and / or second contact angle is small when the electromagnetic clutch guide member is initially retracted. And the said 1st and / or 2nd contact angle expands as a guide member is drawn in to the axial direction one side. When the first and / or second contact angle is small, the ratio of the circumferential torque component is high, and when the first and / or second contact angle is large, the circumferential torque component is large. The rate is low. Since the ratio of the torque component force in the circumferential direction can be increased at the initial pull-in time of the guide member when the attractive force of the electromagnetic clutch is small, the rotation acting on the first and second cages at the initial pull-in time by the electromagnetic clutch High driving force can be maintained. Therefore, it is possible to satisfactorily switch between transmission / disconnection of the rotational driving force in the driving force transmission device.

  According to the second aspect, since the first and / or second sliding contact surface has a convex curved surface, the first and / or the second are in accordance with the movement of the guide member to the one side in the axial direction. Increases contact angle. As a result, the first contact angle increases as the guide member moves toward the one axial side, and / or the second as the guide member moves toward the one axial side relative to the second cage. A structure with an increased contact angle can be realized with a simple configuration.

  According to the third aspect, the first and / or second sliding surface has a convexly curved cross-sectional shape along the radial direction. When the guide member has an inclined posture with respect to the circumferential direction, the first and / or second sliding surfaces may be inclined with respect to the circumferential direction. Since the second sliding surface has the above-described shape, the first and / or second sliding surface is prevented from unevenly contacting the cage (first and / or second cage). it can.

According to the fourth aspect, the first and / or second slidable contact surface is formed of a concave curved surface having a smaller curvature than the first curved portion with respect to the axial direction. The guide member can be smoothly moved in the axial direction with respect to the cage.
According to claim 5, the first and / or second sliding contact surface includes an inclined surface formed of a flat surface.

  Due to the dimensional tolerance of the guide member, the axial position of the guide member varies at the initial stage of retracting the guide member, and as a result, the rotational driving force acting on the first and second cages may vary at the initial stage of retracting. . However, by providing the inclined surface so that the first and / or second slidable contact surface is in contact with the inclined surface formed of a flat surface at the initial stage of retracting the guide member, the first at the initial stage of retracting the guide member. And / or variation in the second contact angle can be suppressed.

It is sectional drawing of the driving force transmission apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the structure of the two-way clutch contained in a driving force transmission apparatus. It is a disassembled perspective view which shows the structure of the said two-way clutch. It is sectional drawing which looked at the structure of the said two-way clutch from the cut surface line IV-IV of FIG. FIG. 5A and FIG. 5B are perspective views showing the configuration of the wedge member. FIG. 6A is a cross-sectional view of the wedge member as seen from the cutting plane line VIA-VIA of FIG. FIG. 6B is a cross-sectional view of the wedge member as seen from the section line VIB-VIB in FIG. FIG. 6C is a cross-sectional view of the wedge member as seen from the section line VIC-VIC in FIG. It is a side view which shows the positional relationship between the said wedge member and an inner side and an outer side holder | retainer in the fastening state of the said two-way clutch. It is sectional drawing which shows the structure of the said two-way clutch in the released state of the said two-way clutch. It is a side view which shows the positional relationship between the said wedge member and an inner side and an outer side holder | retainer in the releasing state of the said two-way clutch. It is a schematic diagram which shows the change of the 1st and 2nd contact angle accompanying pulling in of the wedge member by an electromagnetic clutch. It is a graph which shows the relationship between the movement distance from the 1st position of the said wedge member, and the rotational torque which acts on an inner side and an outer side holder | retainer. It is a schematic diagram which shows the positional relationship between the said wedge member and an inner side and an outer side holder | retainer in the driving force transmission apparatus which concerns on other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view of a driving force transmission device 1 according to an embodiment of the present invention. The driving force transmission device 1 is a device that can switch transmission / disconnection of rotational torque (rotational driving force) between a first shaft body 2 and a second shaft body 3 that are arranged coaxially with each other.
The driving force transmission apparatus 1 includes an inner ring 4 that is coaxially and integrally connected to a first shaft body 2 as an input shaft, and an outer ring 5 that is coaxially and integrally connected to a second shaft body 3 as an output shaft. , A two-way clutch 6 for transmitting / disconnecting a rotational driving force from the inner ring 4 to the outer ring 5, an electromagnetic clutch 7 for operating the fastening / release of the two-way clutch 6, an inner ring 4, an outer ring 5, a two-way clutch 6 and an electromagnetic And a housing 8 that houses the clutch 7.

  The driving force transmission device 1 is mounted on, for example, a steering device. Specifically, the driving force transmission device 1 is interposed between a steering shaft connected to a steering member such as a steering wheel and a turning shaft of a turning mechanism such as a rack and pinion. The steering device is provided with a steer-by-wire system that detects the operation angle of the steering member by an angle sensor and transmits the driving force of the steering motor controlled according to the sensor output to the steering shaft. ing. At normal times, the steer-by-wire system is activated, the two-way clutch 6 is released, and the transmission of rotational torque between the steering shaft and the steered shaft is cut off. In an emergency, the steer-by-wire system is temporarily disabled, and the two-way clutch 6 of the driving force transmission device 1 is engaged to transmit rotational torque between the steering shaft and the steered shaft. The

  In the following description, the axial direction of the rotation axis C of the first and second shaft bodies 2 and 3 is referred to as an axial direction X. The axial direction of the inner ring 4, the axial direction of the outer ring 5, the axial direction of the electromagnetic clutch 7, and the axial direction of the two-way clutch 6 coincide with the axial direction X. Further, in the axial direction X, the axial direction (right direction in FIG. 1) on the first shaft body 2 side when viewed from the two-way clutch 6 is one axial direction X1, and the axial direction X is viewed from the two-way clutch 6. The axial direction (left direction in FIG. 1) on the second shaft body 3 side is defined as the other axial direction X2.

The rotational radial direction of the first and second shaft bodies 2 and 3 is defined as a radial direction Z. The radial direction of the inner ring 4, the radial direction of the outer ring 5, and the radial direction of the two-way clutch 6 coincide with the radial direction Z.
A circumferential direction Y is defined as a circumferential direction of the first and second shaft bodies 2 and 3. The circumferential direction of the inner ring 4, the circumferential direction of the outer ring 5, the circumferential direction of the electromagnetic clutch 7, and the circumferential direction of the two-way clutch 6 coincide with the circumferential direction Y. Further, in the circumferential direction Y, the clockwise circumferential direction when viewed from the other axial direction X2 side is defined as one circumferential direction Y1, and among the circumferential directions Y, the counterclockwise circumferential direction as viewed from the other axial direction X2 side is circumferential. The other direction is Y2.

The housing 8 has a cylindrical shape, and a small-diameter bearing cylinder 9 is formed at the end portion on the other axial direction X2 side. The second shaft body 3 is supported so as to be rotatable and immovable in the axial direction X by a first rolling bearing 10 fixed to the inner periphery of the bearing cylinder 9.
The inner ring 4 is formed using, for example, a steel material, and integrally includes a shaft portion 11 and a large-diameter portion 12 provided in the middle portion of the shaft portion 11 in the axial direction X. FIG. 1 shows an example in which the inner ring 4 is provided integrally with the first shaft body 2 at the shaft end, but the inner ring 4 is provided as a separate member with respect to the first shaft body 2. The first shaft body 2 may be coupled so as to be able to rotate together.

The outer ring 5 has a cylindrical shape with a closed end on the other axial side X2 side, and is formed using a steel material. The second shaft body 3 is connected to the closed end of the outer ring 5. 1 shows an example in which the closed end of the outer ring 5 is provided integrally with the second shaft body 3, but the outer ring 5 is provided as a separate member from the second shaft body 3, and the inner ring 4 and the second You may connect with the shaft body 3 so that accompanying rotation is possible.
A first annular step 13 and a second annular step 14 having a larger diameter than the first annular step 13 are formed on the inner circumference of the outer ring 5 in this order from the end on the other axial X2 side. Has been. The inner ring 4 is supported rotatably and immovably in the axial direction X by a second rolling bearing 15 fixed to the inner periphery of the first annular step portion 13.

The two-way clutch 6 is disposed between the inner ring 4 and the outer ring 5. That is, the two-way clutch 6 can switch between transmission / disconnection of rotational torque between the inner ring 4 and the outer ring 5.
FIG. 2 is a perspective view showing the configuration of the two-way clutch 6. FIG. 3 is an exploded perspective view showing the configuration of the two-way clutch 6. The configuration of the two-way clutch 6 will be described below with reference to FIGS. 2 and 3, the large-diameter portion 12 is mainly illustrated in the inner ring 4. 2 to 4, the outer ring 5 is not shown. FIG. 4 shows the engaged state of the two-way clutch 6. 4 is a cross-sectional view of the configuration of the two-way clutch 6 as seen from the section line IV-IV in FIG.

  The two-way clutch 6 is provided on the cylindrical surface 21 provided on the inner periphery of the second annular step portion 14 of the outer ring 5 and the outer periphery of the large-diameter portion 12 of the inner ring 4 so as to be arranged at equal intervals in the circumferential direction Y. A plurality of (for example, three) cam surfaces 22, a plurality of (for example, three) roller pairs 23, a plurality (the same number as the number of roller pairs 23) of elastic members 24, and the roller pairs 23 and the elastic members 24 are held. And a plurality of (same as the number of roller pairs 23) synthetic resin wedge members (guide members) 26 connected to the armature 71 of the electromagnetic clutch 7 so as to be movable in the axial direction X. The cam surfaces 22 are arranged at equal intervals in the circumferential direction Y on the outer periphery of the inner ring 4. A plurality of cam surfaces 22 may be provided on the inner periphery of the outer ring 5, and a cylindrical surface may be provided on the outer periphery of the inner ring 4. Further, an elastic member holder that collectively supports the plurality of elastic members 24 may be attached to the outer periphery of the inner ring 4.

  As shown in FIG. 4, the cylindrical surface 21 of the outer ring 5 and the cam surfaces 22 of the inner ring 4 face each other in the radial direction Z. Each cam surface 22 is provided with a pair of inclined surfaces 27a and 27b provided to incline in opposite directions with respect to the circumferential direction Y, and a tangential direction of the inner ring 4 provided between the pair of inclined surfaces 27a and 27b. And a flat spring support surface 28. A wedge space 29 is formed between each cam surface 22 and the cylindrical surface 21. Each wedge space 29 becomes narrower toward both ends in the circumferential direction Y.

  As shown in FIG. 4, each roller pair 23 includes a first roller 23 a disposed on the one circumferential side Y <b> 1 side and a second roller 23 b disposed on the other circumferential direction Y <b> 2 side. In each wedge space 29, a first roller 23a and a second roller 23b are arranged so as to face each other. In each wedge space 29, an elastic member 24 that elastically presses the first and second rollers 23a and 23b in the circumferential direction Y away from each other is disposed. An example of the elastic member 24 is a compression coil spring. Further, as the elastic member 24, other types of springs such as a leaf spring or a rubber material can be used. One end 24a of each elastic member 24 elastically presses the corresponding first roller 23a toward one circumferential direction Y1, and the other end 24b of each elastic member 24 presses the corresponding second roller 23b to the other circumferential direction. It is elastically pressed toward the Y2 side. The elastic member 24 is supported by the spring support surface 28.

  As shown in FIGS. 2 and 3, the retainer 25 includes an inner retainer (first retainer) 31 and an outer retainer (second retainer) 32 provided as separate members. The inner cage 31 and the outer cage 32 are provided so as to be rotatable relative to each other. The inner cage 31 includes a thin disc-shaped first annular portion 33, an annular third annular portion 34 that is coaxially and axially disposed on the one X1 side with respect to the first annular portion 33, and a first annular portion 34, A plurality of connection portions 35 (the same number as the number of roller pairs 23) connecting the one annular portion 33 and the third annular portion 34. The first and third annular portions 33 and 34 (that is, the inner cage 31) are fitted on the outer periphery of the large-diameter portion 12 of the inner ring 4 so as to be rotatable relative to the inner ring 4. The first annular portion 33 is provided so as to contact the large diameter portion 12 from the other axial direction X2 side. Since the inner cage 31 is externally fitted to the inner ring 4 at a plurality of locations in the axial direction X, the inner cage 31 can be favorably supported by the inner ring 4.

  As shown in FIG. 3, the same number of connection portions 35 as the number of roller pairs 23 (three in this embodiment) are provided, and are arranged at equal intervals in the circumferential direction Y. The first annular portion 33, the third annular portion 34, and the plurality of connecting portions 35 are integrally formed using a synthetic resin material (for example, polyacetal, polyamide, polytetrafluoroethylene, polyetheretherketone, polyphenylene sulfide, etc.). Is formed.

  Each connection portion 35 has a columnar shape extending along the axial direction X. Each connection portion 35 is a first protrusion 36 that protrudes from the outer periphery of the first annular portion 33 toward the one axial direction X1. A first abutting surface 37 (mainly see FIG. 4) capable of abutting (pressing) the first roller 23a of the roller pair 23 is formed on the surface on the other circumferential side Y2 side of each connecting portion 35. . The first contact surface 37 is constituted by, for example, a flat surface. That is, the first contact surface 37 can come into surface contact with the first roller 23a. However, the first contact surface 37 is not limited to the surface contact with the first roller 23a, and may be in a line contact or point contact with the first roller 23a.

  A first sliding contact surface 38 (mainly see FIGS. 3 and 4) is formed on the surface on the Y1 side in the circumferential direction of each connection portion 35 so as to be in sliding contact with the corresponding wedge member 26. The first slidable contact surface 38 is configured by a first concave curved surface 103 that goes in the circumferential direction Y1 as it goes in the axial direction X1. The first concave curved surface 103 has an arc shape or an elliptic arc shape in cross section along the axial direction X. The first concave curved surface 103 is concavely curved with respect to the axial direction X with a smaller curvature than the first convex curved surface 101 of the first sliding contact surface 53 described later. The first concave curved surface 103 is configured by a single concave curved surface or a combination of a plurality of concave curved surfaces.

  Since the first contact surface 37 is provided at each connection portion 35 connecting the first and third annular portions 33, 34, the first protrusion 36 provided with the first contact surface 37 is provided. Compared with the case where it is provided as a separate member from the connecting portion 35, the number of parts can be reduced. In addition, since the first sliding contact surface 38 is provided in each connection portion 35, the component in which the first sliding contact surface 38 is provided as a separate member from the connection portion 35 is provided. The number of points can be reduced.

  The outer cage 32 has an annular second annular portion 39 and a plurality of second protrusions 40 that protrude from the inner circumference of the second annular portion 39 toward the other axial direction X2. . The second annular portion 39 is fitted on the outer periphery of the outer ring 5 so as to be rotatable relative to the outer ring 5. The second annular portion 39 is arranged so that the outer ring 5 surrounds the outer periphery of the third annular portion 34. The same number of second protrusions 40 as the number of roller pairs 23 (three in this embodiment) are provided, and are arranged at equal intervals in the circumferential direction Y. The second annular portion 39 and the plurality of second protrusions 40 are integrally formed using a synthetic resin material (for example, polyacetal, polyamide, polytetrafluoroethylene, polyetheretherketone, polyphenylene sulfide, etc.). Yes.

  A recess 80 that is recessed outward in the radial direction Z is formed along the axial direction X on the inner periphery of the second annular portion 39. The number of recesses 80 corresponds to each second protrusion 40 on a one-to-one basis, and is provided in the same number (for example, three) as the number of second protrusions 40. Each recessed part 80 is formed in the 2nd annular body 39 in the position adjacent to the other circumferential direction other Y2 side of the 2nd protrusion 40 corresponding. Each recess 80 is a recess through which the insertion portion 51 of the wedge member 26 is inserted. In addition, each recessed part 80 is provided long in the circumferential direction Y, and the side surface 81 on the other circumferential direction Y2 side abuts on an engaging convex part (not shown) provided in the inner retainer 31 to hold the inner part. The relative rotation amount between the container 31 and the outer holder 32 may be regulated.

  A second contact surface 41 (mainly see FIG. 4) that can contact (press) the second roller 23b of the roller pair 23 is formed on the surface on the Y1 side in the circumferential direction of each second annular portion 39. Has been. The second contact surface 41 is constituted by, for example, a flat surface. That is, the second contact surface 41 can come into surface contact with the second roller 23b. However, the second contact surface 41 is not limited to the surface contact with the second roller 23b, and may be in a line contact or point contact with the second roller 23b.

  A second slidable contact surface 42 (mainly see FIGS. 3 and 4) is formed on the surface on the other circumferential side Y2 side of each second annular portion 39 in contact with the corresponding wedge member 26. The second sliding contact surface 42 has a second concave curved surface 104 that goes to the other circumferential direction Y2 as it goes to the one axial direction X1. The second concave curved surface 104 has an arc shape or elliptic arc shape in cross section along the axial direction X. The second concave curved surface 104 is concavely curved with respect to the axial direction X with a smaller curvature than the second convex curved surface 102 of the second sliding contact surface 54 described later. The second concave curved surface 104 is configured by a single concave curved surface or a combination of a plurality of concave curved surfaces.

Since each second protrusion 40 is provided with a second slidable contact surface 42, the member provided with the second slidable contact surface 42 is compared with the case where the second protrusion 40 is provided as a separate member. Thus, the number of parts can be reduced.
As shown in FIG. 2, the inner cage 31 and the outer cage 32 are combined such that a plurality of connection portions 35 and a plurality of second protrusions 40 are alternately arranged in the circumferential direction Y. On the other circumferential side Y2 side of each connecting portion 35, a second protrusion 40 that can press the second roller 23b that makes a pair with the first roller 23a that can be pressed by the connecting portion 35 is a roller pair 23. Next to each other. In addition, on the one Y1 side in the circumferential direction of each connecting portion 35, the second roller pair 23 adjacent on the one Y1 side in the circumferential direction of the roller pair 23 including the first roller 23a that can press the connecting portion 35 is included. The second protrusions 40 (hereinafter referred to as “second protrusions 40 of the adjacent roller pair 23”) that can be pressed against the roller 23b are adjacent to each other via the wedge member 26. That is, with respect to the inner cage 31 and the outer cage 32, the connecting portion 35 that can press the first roller 23a of each roller pair 23, and the roller pair 23 adjacent to the roller pair 23 in the circumferential direction one Y1 side. The second protrusions 40 capable of pressing the two rollers 23 b are adjacent to each other via one wedge member 26.

  As shown in FIGS. 2 and 3, each of the rollers 23 a and 23 b is moved toward the X1 side in the axial direction by both the third annular portion 34 of the inner retainer 31 and the second annular portion 39 of the outer retainer 32. Movement (ie, omission) is restricted. Further, the movement of each roller 23a, 23b toward the other X2 side in the axial direction (that is, removal) is restricted by the first annular portion 33 of the inner cage 31. In addition, the movement of each roller 23a, 23b toward the one X1 side in the axial direction may be restricted by only one of the third annular portion 34 and the second annular portion 39.

A corresponding wedge member 26 is inserted between each connecting portion 35 and the second protrusion 40 of the adjacent roller pair 23.
FIG. 5 is a perspective view showing the configuration of the wedge member 26. 5A and 5B, the wedge member 26 is viewed from two different directions.
Each wedge member 26 includes an insertion portion 51 inserted between the connection portion 35 (see FIG. 2 and the like) and the second protrusion 40 (see FIG. 2 and the like) of the adjacent roller pair 23, and a shaft of the insertion portion 51. And a wedge portion 52 that extends in the circumferential direction Y from the other end in the direction X. The insertion portion 51 extends in a rod shape along the axial direction X, and the shape of the cross section perpendicular to the axis is rectangular. The wedge portion 52 includes a first sliding contact surface 53 provided on the surface on the other circumferential side Y2 side and a second sliding contact surface 54 provided on the surface on the one circumferential side Y1 side.

FIG. 6A is a cross-sectional view of the wedge member 26 as viewed from the cutting plane line VIA-VIA of FIG. FIG. 6B is a cross-sectional view of the wedge member 26 as seen from the section line VIB-VIB in FIG. FIG. 6C is a cross-sectional view of the wedge member 26 as seen from the section line VIC-VIC in FIG.
The first slidable contact surface 53 is constituted by a spherical or substantially spherical first convex curved surface 101 (first curved portion and second curved portion). In other words, the first convex curved surface 101 is convexly curved so that the cross-sectional shape along the axial direction X is directed toward the other circumferential direction Y2 as it goes toward the one axial direction X1. In addition, the first convex curved surface 101 is convexly curved so that the cross-sectional shape along the radial direction Z is directed from the both ends of the radial direction Z toward the other center in the radial direction Z toward the other circumferential direction Y2. As shown in FIGS. 10A and 10B, which will be described later, the radius of curvature of the first convex curved surface 101 in the axial direction X becomes smaller toward the one axial direction X1 (R). _1A > R _1B ). That is, the curvature with respect to the axial direction X of the first convex curved surface 101 increases toward the one axial direction X1.

The second slidable contact surface 54 is constituted by a spherical or substantially spherical second convex curved surface 102 (a first curved portion and a second curved portion). In other words, the second convexly curved surface 102 is convexly curved so that the cross-sectional shape along the axial direction X is directed toward the circumferential direction Y1 as it goes toward the axial direction X1. In addition, the second convex curved surface 102 is convexly curved so that the cross-sectional shape along the radial direction Z is directed to one circumferential direction Y1 from both ends of the radial direction Z toward the central portion of the radial direction Z. As shown in FIGS. 10A and 10B, which will be described later, the radius of curvature of the second convex curved surface 102 in the axial direction X becomes smaller toward the one axial direction X1 (R). _2A > _R2B ). That is, the curvature with respect to the axial direction X of the second convex curved surface 102 increases toward the one axial direction X1.

As shown in FIG. 1, the electromagnetic clutch 7 includes an annular armature 71 to which a plurality of wedge members 26 are connected, an annular rotor 72 facing the armature 71 on the one axial side X1 and the axial direction of the rotor 72. On the other hand, an electromagnet 73 disposed on the X1 side is included.
The armature 71 is disposed on the X1 side in the axial direction via the back plate 70 with respect to the third annular portion 34 of the inner cage 31 and the second annular portion 39 of the outer cage 32.

  The back plate 70 has an annular shape and is externally fitted and fixed to the shaft portion 11 of the inner ring 4. The back plate 70 is formed using, for example, a steel material. The main surface on the X1 side in the axial direction of the back plate 70 is in sliding contact with the main surface on the other X2 side in the axial direction of the third annular portion 34 and the second annular portion 39, respectively. A plurality of insertion holes 82 (the same number as the number of wedge members 26) are arranged in the back plate 70 at equal intervals in the circumferential direction Y. Each insertion hole 82 (only one is shown in FIG. 1) is provided on the wedge member 26 in a one-to-one correspondence. Each wedge member 26 is connected and fixed to the armature 71 through the corresponding insertion hole 82.

  The armature 71 is provided so as to be rotatable and movable in the axial direction X with respect to the housing 8 and the inner ring 4. The rotor 72 is externally fitted and fixed to the outer periphery of the inner ring 4. The electromagnet 73 includes an electromagnetic coil 73a and a core 73b that supports the electromagnetic coil 73a. The outer periphery of the core 73b is fitted and fixed to the housing 8. The inner periphery of the core 73 b is supported by a third rolling bearing 74 that is externally fitted and fixed to the inner ring 4 so as to be relatively rotatable with respect to the inner ring 4 and not relatively movable in the axial direction X. The third bearing 74 makes the electromagnet 73 and the first shaft body 2 relatively rotatable.

FIG. 7 is a side view showing the positional relationship between the wedge member 26 and the inner cage 31 and the outer cage 32 when the two-way clutch 6 is engaged. FIG. 8 is a cross-sectional view showing a configuration of the two-way clutch 6 in a released state of the two-way clutch 6, and is a cross-sectional view taken along the section line IV-IV in FIG. FIG. 9 is a side view showing the positional relationship between the wedge member 26 and the inner cage 31 and the outer cage 32 when the two-way clutch 6 is released. FIG. 10 is a schematic diagram showing changes in the first contact angle θ ₁ and the second contact angle θ ₂ due to the retracting of the wedge member 26 by the electromagnetic clutch 7.

  As shown in FIGS. 4 and 7, when the electromagnetic clutch 7 is in the off state, the two-way clutch 6 is in the engaged state, and the armature 71 is not attracted by the electromagnet 73. Therefore, the armature 71 is located at the initial position, and the wedge member 26 provided in the armature 71 so as to be movable in the axial direction X is disposed at the first position (initial position, the position of the wedge member 26 shown in FIG. 7). Yes.

Contact angle (the contact) at a contact point PC1 ( first contact point; see FIG . 10A) between the first sliding contact surface 53 (first convex curved surface 101) and the first sliding contact surface 38 . An acute angle gradient formed between a tangent line along the axial direction X of the first sliding contact surface 53 at the point PC1 and the axial direction X is defined as a _first contact angle θ1, and the second sliding contact surface 54 (second Of the second curved surface 102) and the second sliding contact surface 42 at a contact point PC2 ( second contact point, see FIG . 10B) (second sliding contact surface 54 at the contact point PC2) . the angle gradient) of acute angle with the axial direction X along the tangential and axial direction X is, as a second contact angle theta _2, will be described below.

Wedge member 26 is in the state of being disposed in a first position, as shown in FIG. 10 (A), the first contact angle theta ₁ and the second size of the contact angle theta ₂ is relatively small, respectively.
In this state, as shown in FIG. 4, each first roller 23 a is moved by the elastic member 24 toward the first engagement position 29 a provided at the end of the wedge space 29 on the one circumferential side Y1 side. It is elastically pressed. When the first roller 23a is in the first engagement position 29a, the first roller 23a is engaged with the outer periphery of the inner ring 4 (large diameter portion 12) and the inner periphery of the outer ring 5 (second annular step portion 14). Match. Further, in this state, each second roller 23 b is elastically pressed by the elastic member 24 toward the second engagement position 29 b provided at the end portion on the other circumferential side Y <b> 2 side of the wedge space 29. When the second roller 23b is in the second engagement position 29b, the second roller 23b is placed on the outer periphery of the inner ring 4 (large diameter portion 12) and the outer periphery of the outer ring 5 (second annular step portion 14). Engage. Thus, in the off state of the electromagnetic clutch 7, the first and second rollers 23a, 23b are engaged with the outer periphery of the inner ring 4 and the inner periphery of the outer ring 5, so that the two-way clutch 6 is engaged. become.

  On the other hand, when the electromagnetic clutch 7 is switched to the ON state, the armature 71 is attracted by the electromagnetic clutch 7 as shown in FIG. 9, so that the plurality of wedge members 26 connected to the armature 71 are moved to the X1 side in the axial direction. Pulled in (moves in the axial direction X). As a result of this drawing, the wedge member 26 is moved to the second position (retracted position; position of the wedge member 26 shown in FIG. 9) on the one axial side X1 from the first position (position of the wedge member 26 shown in FIG. 7). Placed in.

Since the first slidable contact surface 53 provided on the surface on the other circumferential side Y2 side of the wedge member 26 is composed of a surface directed toward the circumferential direction one Y1 toward the axial direction one X1, one axial direction X1 of each wedge member 26. With the movement to the side, the first slidable contact surface 53 is slidably contacted with the first slidable contact surface 38 of the connecting portion 35, and the connecting portion 35 is guided to the other circumferential direction Y2.
In addition, since the second sliding contact surface 54 provided on the surface on the Y1 side in the circumferential direction of the wedge member 26 is composed of a surface toward the other Y2 in the circumferential direction toward the one X1 in the axial direction, the axial direction of each wedge member 26 On the other hand, with the movement toward the X1 side, the second slidable contact surface 54 slides on the second slidable contact surface 42 of the second projecting portion 40 of the adjacent roller pair 23, and the second projecting portion 40 is moved. Guide to the other Y1 side in the axial direction.

  That is, with the movement of each wedge member 26 toward the one axial direction X1, the second projecting portion 40 of the connection portion 35 and the adjacent roller pair 23 is separated from the wedge member 26 (insertion portion 51). As a result, the inner cage 31 rotates toward the other circumferential direction Y2, and the outer cage 32 pivots toward the circumferential direction one Y1 side. As the inner retainer 31 and the outer retainer 32 rotate, the third annular portion 34 of the inner retainer 31 and the second annular portion 39 of the outer retainer 32 slide on the back plate 70, respectively.

As shown in FIGS. 10 (A) and 10 (B), the first convex curved surface 101 is configured such that the radius of curvature with respect to the axial direction X becomes continuously smaller toward the one axial direction X1 ( R _1A > R _1B ). That is, the curvature with respect to the axial direction X of the first convex curved surface 101 continuously increases toward the one axial direction X1. In addition, the first concave curved surface 103 is concavely curved with a smaller curvature than the first convex curved surface 101 in the axial direction X. Therefore, with the movement in the axial direction X1 side of the wedge member 26, the size of the first contact angle theta ₁ is enlarged continuously.

Further, as shown in FIGS. 10 (A) and 10 (B), the second convex curved surface 102 becomes such that the radius of curvature with respect to the axial direction X becomes continuously smaller toward the one axial direction X1. (R _2A > R _2B ). That is, the curvature of the second convex curved surface 102 in the axial direction X is continuously increased toward the one axial direction X1. In addition, the second concave curved surface 104 is concavely curved with a smaller curvature than the second convex curved surface 102 in the axial direction X. Therefore, with the movement in the axial direction X1 side of the wedge member 26, the size of the second contact angle theta ₂ is enlarged continuously. In other words, the size of the first and second contact angles θ ₁ and θ ₂ is continuously increased as the wedge member 26 moves toward the one side X1 in the axial direction. In a state where the wedge member 26 is disposed at the second position (the state shown in FIG. 10B), a comparison is made with a state where the wedge member 26 is disposed at the first position (the state shown in FIG. 10A). to the contact angle theta ₂ of the first contact angle theta ₁ and the second is expanding, respectively.

  As the inner cage 31 rotates to the other Y2 side in the circumferential direction, each first contact surface 37 moves to the other Y2 side in the circumferential direction, and as a result, comes into contact with the corresponding first roller 23a. The first roller 23a is pressed toward the other circumferential direction Y2. Accordingly, each first roller 23a is moved toward the other circumferential direction Y2 against the elastic pressing force of the elastic member 24. As a result, each first roller 23a is disengaged from the first engagement position 29a (see FIG. 4), and a gap is formed between each first roller 23a and the inner periphery of the outer ring 5, as shown in FIG. S1 is formed. As a result, each first roller 23 a is disengaged from the outer periphery of the inner ring 4 and the inner periphery of the outer ring 5.

  Further, as the outer cage 32 rotates toward the one Y1 side in the circumferential direction, each second abutment surface 41 moves toward the one Y1 side in the circumferential direction, and as a result, contacts the corresponding second roller 23b. In contact therewith, the second roller 23b is pressed toward one circumferential direction Y1. Accordingly, the second roller 23b is moved toward one circumferential direction Y1 against the elastic pressing force of the elastic member 24. Thereby, each 2nd roller 23b remove | deviates from the 2nd engagement position 29b (refer FIG. 4), and as shown in FIG. 8, it is a clearance gap between each 2nd roller 23b and the inner periphery of the outer ring | wheel 5. As shown in FIG. S2 is formed. As a result, each second roller 23 b is disengaged from the outer periphery of the inner ring 4 and the inner periphery of the outer ring 5.

In this way, when the electromagnetic clutch 7 is in the on state, the rollers 23a and 23b are disengaged from the outer periphery of the inner ring 4 (large diameter portion 12) and the inner periphery of the outer ring 5, whereby the two-way clutch 6 is released. Become.
FIG. 11 is a graph showing the relationship between the moving distance of the wedge member 26 from the first position and the rotational torque (cage rotational torque) acting on the inner cage 31 and the outer cage 32. In FIG. 11, “Example” refers to the driving force transmission device 1 according to the present embodiment, and “Comparative Example” refers to a driving force transmission device equivalent to the driving force transmission device 1. The first and second slidable contact surfaces 53 and 54 are each configured by a flat inclined surface, and the first and second slidable contact surfaces 38 and 42 are configured by flat inclined surfaces that match the first and second slidable contact surfaces 38 and 42. The driving force transmission device. From the graph of FIG. 11, in the comparative example, the rotational torque acting on the inner retainer 31 and the outer retainer 32 is extremely small in a state where the moving distance of the wedge member 26 is short (that is, when the electromagnetic clutch 7 is initially retracted). I understand. On the other hand, in the embodiment, even when the movement distance of the wedge member 26 is short (that is, at the time of initial pull-in by the electromagnetic clutch 7), it is possible to suppress a drop in rotational torque that acts on the inner cage 31 and the outer cage 32. I understand.

As described above, according to this embodiment, the first contact angle θ ₁ and the second contact angle θ ₂ are small at the initial stage of retracting the wedge member 26 by the electromagnetic clutch 7. The first contact angle theta ₁ and the second contact angle theta ₂ is enlarged in accordance with the wedge member 26 is pulled in the axial direction X1 side. In the state where the first contact angle θ ₁ and the second contact angle θ ₂ are small, the ratio of the torque component force in the circumferential direction Y is high. On the other hand, when the first contact angle θ ₁ and the second contact angle θ ₂ are large, the ratio of the torque component force in the circumferential direction Y is low. Since the ratio of the torque component force in the circumferential direction Y can be increased at the initial stage of retracting the wedge member 26 where the suction force of the electromagnetic clutch 7 is small, the inner cage 31 and the outer cage at the initial stage of retracting by the electromagnetic clutch 7. The rotational torque acting on 32 can be maintained high. Therefore, the two-way clutch 6 can be satisfactorily switched from the engaged state to the disengaged state, whereby the driving force transmission device 1 can be favorably switched between transmission / disconnection of rotational torque.

Further, the cross-sectional shape along the axial direction X of the first sliding contact surface 53 is convexly curved so as to go to one circumferential direction Y1 as going to one axial direction X1. Further, the cross-sectional shape along the axial direction X of the second slidable contact surface 54 is convexly curved so as to go to the other circumferential direction Y2 toward the one axial direction X1. Therefore, the first contact angle theta ₁ and the second contact angle theta ₂ is enlarged, respectively according to the wedge member 26 is moved in the axial direction X1 side. As a result, a structure in which the first contact angle θ ₁ and the second contact angle θ ₂ expand as the wedge member 26 moves toward the one side X1 in the axial direction can be realized with a simple configuration.

  Further, the cross-sectional shape along the circumferential direction Y of the first sliding contact surface 53 is convexly curved so as to go to the other circumferential direction Y2 from both ends of the radial direction Z toward the center of the radial direction Z. Further, the cross-sectional shape along the circumferential direction Y of the second slidable contact surface 54 is convexly curved so as to go to one side Y1 in the circumferential direction from the both end portions in the radial direction Z toward the central portion in the radial direction Z. When the wedge member 26 is inclined with respect to the circumferential direction Y, the first sliding contact surface 53 and the second sliding contact surface 54 may be inclined with respect to the circumferential direction Y. In such a case, In addition, since the first slidable contact surface 53 and the second slidable contact surface 54 include the convex curved surfaces 101 and 102, the first slidable contact surface 53 and the second slidable contact surface 54 are It is possible to prevent the contact surface 38 and the second slidable contact surface 42 from being biased (per point).

  The first sliding contact surface 38 is composed of a concave curved surface 103 having a smaller curvature than the first convex curved surface 101, and the second sliding contact surface 42 is the second curved contact surface 42. The concave curved surface 104 has a smaller curvature than the convex curved surface 102. Therefore, the axial X movement of the wedge member 26 with respect to the inner cage 31 and the outer cage 32 can be performed smoothly.

FIG. 12 is a schematic diagram showing a positional relationship between the wedge member 26, the inner cage 31 and the outer cage 32 in a driving force transmission device 201 according to another embodiment of the present invention.
The driving force transmission device 201 according to another embodiment of the present invention is different from the driving force transmission device 1 according to the above-described embodiment in that the first sliding contact surface 38 is the third concave curved surface 203. And the flat first inclined surface 211, and the second slidable contact surface 42 includes a fourth concave curved surface 204 and a flat second inclined surface 212. It is a point. In the driving force transmission device 201, the wedge member 26 similar to that in the above-described embodiment is employed as the guide member. In FIG. 12, portions corresponding to the respective portions shown in the above-described embodiment are denoted by the same reference numerals as those in FIGS. 1 to 11 and description thereof is omitted. FIG. 12 shows a state in which the wedge member 26 is located at the first position (initial position).

  The third concave curved surface 203 is concavely curved so as to go to one circumferential direction Y1 as going to one axial direction X1. The third concave curved surface 203 is concavely curved with a smaller curvature than the first convex curved surface 101 in the axial direction X. In the third concave curved surface 203, the cross-sectional shape along the axial direction X is an arc shape or an elliptical arc shape. The third concave curved surface 203 is configured by a single concave curved surface or a combination of a plurality of concave curved surfaces. The first inclined surface 211 is continuous with the end portion on the other X2 side in the axial direction of the third concave curved surface 203. If the boundary portion between the first inclined surface 211 and the third concave curved surface 203 is a boundary portion 221, the angular gradient at each position of the first inclined surface 211 and the third concave curved surface 203 is the boundary. It is continuous in the axial direction X across the portion 221.

  The fourth concave curved surface 204 is concavely curved so as to go to the other circumferential direction Y2 as it goes to one axial direction X1. The fourth concave curved surface 204 is concavely curved with a smaller curvature than the second convex curved surface 102 in the axial direction X. The fourth concave curved surface 204 has an arc shape or an elliptic arc shape in cross section along the axial direction X. The fourth concave curved surface 204 is configured by a single concave curved surface or a combination of a plurality of concave curved surfaces. The second inclined surface 212 is continuous with the end portion on the other X2 side in the axial direction of the fourth concave curved surface 204. If the boundary portion between the second inclined surface 212 and the fourth concave curved surface 204 is defined as a boundary portion 222, the angular gradient at each position of the second inclined surface 212 and the fourth concave curved surface 204 is the boundary. It is continuous in the axial direction X across the portion 222.

  As shown in FIG. 12, the first and second inclined surfaces 211 and 212 are arranged such that the wedge member 26 is located at the first position (position shown in FIG. 12). One convex curved surface 101) is in contact with the first inclined surface 211 of the first sliding contact surface 38, and the second sliding contact surface 54 (second convex curved surface 102) is the second. The sliding contact surface 42 is provided so as to be in contact with the second inclined surface 212.

When the electromagnetic clutch 7 is turned on, the wedge member 26 is drawn toward the one side X1 in the axial direction. In a period of time after the start of pull-in (at the time of initial pull-in), the first sliding contact surface 53 comes into contact with the first inclined surface 211 of the first sliding contact surface 38, and the second sliding contact surface 54 Of the second sliding contact surface 42, it comes into contact with the second inclined surface 212. When the wedge member 26 is further retracted, the first sliding contact surface 53 comes into contact with the third concave curved surface 203 of the first sliding contact surface 38 and the second sliding contact surface 54 The second slidable contact surface 42 comes into contact with the fourth concave curved surface 204. The first contact angle θ ₁ and the second contact angle θ ₂ increase as the amount of the wedge member 26 retracted increases.

As described above, according to the embodiment shown in FIG. 12, the same effects as those of the embodiment shown in FIGS.
In addition, the first position of the wedge member 26 (see FIGS. 7 and 12) may vary from product to product due to dimensional tolerances of the wedge member 26. In this case, if the first and second slidable contact surfaces 38 and 42 are provided with only concave curved surfaces, there is a risk that variations in the contact angles θ ₁ and θ ₂ at the initial pull-in time will become significant. As a result, the rotational torque acting on the inner and outer cages 31 and 32 may vary.

On the other hand, in the embodiment shown in FIG. 12, in the state where the wedge member 26 is located at the first position (see FIG. 12), the first sliding contact surface 53 does not depend on the dimensional tolerance of the wedge member 26. The first sliding surface 38 is in contact with the first inclined surface 211, and the second sliding contact surface 54 is in contact with the second inclined surface 212 of the second sliding surface 42. . When the first sliding contact surface 53 is in contact with the first inclined surface 211 formed of a flat surface, the magnitude of the first contact angle θ ₁ hardly changes as the wedge member 26 moves in the axial direction X. . In addition, when the second sliding contact surface 54 is in contact with the second inclined surface 212 formed of a flat surface, the second contact angle θ ₂ is almost as large as the wedge member 26 moves in the axial direction X. It does not change. Therefore, variations in the contact angles θ ₁ and θ ₂ at the initial pull-in time can be suppressed regardless of the dimensional tolerance of the wedge member 26.

As mentioned above, although two embodiment of this invention was described, this invention can also be implemented with another form.
For example, in each of the above-described embodiments, the first and second convex curved surfaces 101 and 102 of the wedge member 26 have been described as having a curved cross section along the radial direction Z. The cross-sectional shape along the radial direction Z of the convex curved surfaces 101 and 102 may be linear.

  In each of the above-described embodiments, the first and second sliding contact surfaces 53 and 54 have been described as being configured by the convex curved surfaces 101 and 102. However, the first and second sliding contacts are described. You may make it comprise one sliding contact surface among the surfaces 53 and 54 by a flat inclined surface. In this case, the slidable contact surfaces 38 and 42 corresponding to the slidable contact surface having a flat inclined surface have inclined surfaces that match the slidable contact surface.

Moreover, although the inner side retainer 31 was demonstrated as the structure containing the 1st cyclic | annular part 33 and the 3rd cyclic | annular part 34, it is also possible to abolish the 3rd cyclic | annular part 34, for example. Further, the shape of the first annular portion 33 is not limited to an annular shape, and may be another annular shape.
Further, the shape of the second annular portion 39 of the outer cage 32 is not limited to an annular shape, and may be another annular shape.

  In each of the above-described embodiments, the first sliding contact surface 53 that is in sliding contact with the connection portion 35 corresponding to the first roller 23 a and the second protrusion corresponding to the second roller 23 b of the adjacent roller pair 23 are used. The wedge member 26 having both the second sliding contact surface 54 and the second sliding contact surface 54 in sliding contact is provided, and the aspect in which the function of the guide member is exhibited by the plurality of wedge members 26 has been described. You may make it provide the guide member (1st guide member) which has, and the guide member (2nd guide member) which has the 2nd sliding contact surface 54 by another member. In this case, the number of first and second guide members required is the same as the number of roller pairs, and the total number of first and second guide members is twice the number of roller pairs (for example, six). is necessary.

The present invention can be applied not only to a driving force transmission device mounted on a steering device, but also to other driving force transmission mechanisms (for example, a driving force transmission mechanism for switching between two-wheel driving and four-wheel driving). is there.
In addition, the present invention can be variously modified within the scope of the claims.

DESCRIPTION OF SYMBOLS 1 ... Driving force transmission device, 2 ... 1st shaft body, 3 ... 2nd shaft body, 4 ... Inner ring, 5 ... Outer ring, 7 ... Electromagnetic clutch, 23 ... Roller pair, 23a ... 1st roller, 23b ... 2nd roller, 24 ... elastic member, 26 ... wedge member (guide member), 29 ... wedge space, 31 ... inner cage (first cage), 32 ... outer cage (second cage), 38 ... 1st sliding contact surface, 42 ... 2nd sliding contact surface, 53 ... 1st sliding contact surface, 54 ... 2nd sliding contact surface, 71 ... Armature, 101 ... 1st convex curve surface (First and second curved portions), 102 ... second convex curved surface (first and second curved portions), 103 ... first concave curved surface (concave curved surface), 104 ... second concave Curved surface (concave curved surface), 201 ... driving force transmission device, 203 ... third concave curved surface (concave curved surface), 204 ... fourth concave curved surface (concave curved surface), 211 ... first Inclined surface (inclined surface), 212 ... second inclined surface (inclined surface), X ... axial direction, X1 ... one axial direction, X2 ... other axial direction, Y ... circumferential direction, Y1 ... circumferential one direction, Y2 ... circumferential Direction other, Z ... radial direction

Claims (5)

A driving force transmission device capable of switching transmission / disconnection of rotational driving force between a first shaft body and a second shaft body arranged coaxially with each other,
An inner ring coaxially connected to the first shaft body;
A cylindrical outer ring that is coaxially connected to the second shaft body and that is rotatably provided to the inner ring;
A roller pair that is arranged in a circumferential direction in a wedge space formed by the outer periphery of the inner ring and the inner periphery of the outer ring, and includes a first roller on one circumferential side and a second roller on the other circumferential side. ,
A first retainer for retaining the roller pair;
A second holder for holding the pair of rollers, the second holder provided in the first holder for relative rotation;
A first slidable contact surface that is slidably contacted with the first retainer from one circumferential direction; and a second slidable contact surface that is slidably contacted with the second retainer from the other circumferential direction; A guide member provided movably, wherein the first retainer is rotated toward the other circumferential direction in accordance with the movement of the guide member in one axial direction, and the second retainer is A guide member that rotates in one direction,
An armature coupled to the guide member, the electromagnetic clutch having an armature that is movable in the axial direction by driving the armature;
The first cage has a first slidable contact surface slidably contacted with the first slidable contact surface,
The second cage has a second slidable contact surface that is slidably contacted with the second slidable contact surface,
The first sliding contact surface and the first sliding contact surface are:
As the guide member moves to the one side in the axial direction with respect to the first cage, at a first contact point that is a contact point between the first sliding contact surface and the first sliding contact surface. A first contact angle that is an angle formed between a tangent and the axial direction is enlarged, and / or the second slidable contact surface and the second slidable contact surface are:
As the guide member moves to one side in the axial direction with respect to the second cage, the second contact point is a contact point between the second sliding contact surface and the second sliding contact surface. A driving force transmission device provided so that a second contact angle, which is an angle formed by a tangent line and the axial direction, is enlarged.   2. The driving force transmission device according to claim 1, wherein at least one of the first and second slidable contact surfaces has a first curved portion having a convexly curved cross-sectional shape along the axial direction.   The driving force transmission device according to claim 2, wherein the at least one sliding contact surface has a second curved portion in which a cross-sectional shape along a radial direction is convexly curved. Among pre Symbol first and second of the sliding contact surface, wherein at least one of Hisuri contact surface that is in sliding contact with the sliding contact surface is concave curvature with a smaller curvature than the respect axially first curved portion The driving force transmission device according to claim 2, wherein the driving force transmission device is configured by a concave curved surface. Among pre Symbol first and second of the sliding contact surface, wherein at least one of Hisuri contact surface that is in sliding contact with the sliding contact surface is concave curvature with a smaller curvature than the respect axially first curved portion 4. The driving force transmission device according to claim 2, wherein the driving force transmission device includes a concave curved surface and a flat inclined surface continuous to the other side in the axial direction with respect to the concave curved surface.

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