Electric friction clutch device

Abstract

To ensure fastening force reliably.SOLUTION: A cam device 5 comprises: a drive cam 37 that has a cam surface 40 on one side in an axial direction, is rotatably supported with respect to a fixed member 10 that does not rotate during use, and cannot be displaced in the axial direction; a holder 38 supported so as to be movable in the axial direction with respect to the fixed member 10 but not rotatable; and a plurality of rolling elements 39 that each have a rolling surface 69 that rolls into contact with the cam surface 40, and are held in the holder 38.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an electric friction clutch device that switches between a connected mode in which a first member and a second member rotate integrally, and a disconnected mode in which the first member and the second member rotate relatively to each other. [Background technology]

[0002] In rotating machinery such as automobiles and machine tools, a transmission is provided between a power source and a driven object in order to efficiently utilize the output of a power source such as an engine or an electric motor. When a gear-type transmission with stages is used as such a transmission, a clutch device is installed between the power source and the transmission, which switches between a locked state in which the output torque of the power source can be transmitted to the transmission and an unlocked state in which the output torque cannot be transmitted. Examples of such clutch devices include a friction clutch that transmits power by friction between a pair of opposing friction surfaces, and a dog clutch that transmits power by meshing pawls.

[0003] A friction clutch can switch between a connected mode in which torque can be transmitted and a disconnected mode in which torque cannot be transmitted, regardless of the phase difference or the difference in rotational speed between a pair of opposing engaging members.

[0004] 31 shows a clutch device 100 described in WO 2008 / 096438. The clutch device 100 is disposed between an input member (rear wheel output shaft) 101 and an output member (sprocket) 102, and switches between a connection mode in which torque is transmitted between the input member 101 and the output member 102, and a disconnection mode in which torque is not transmitted. The clutch device 100 includes a first member 103, a second member 104, a friction engagement portion 105, a cam device 106, an electric actuator 107, a pressing member 108, a rolling bearing 109, and an elastic member 110.

[0005] The first member 103 is coupled and fixed to the input member 101 and rotates integrally with the input member 101. The first member 103 has a small diameter cylindrical portion 103a fitted and fixed to the input member 101, a side plate portion 103b bent radially outward from an end portion on one axial side (left side in FIG. 31) of the small diameter cylindrical portion 103a, and a large diameter cylindrical portion 103c protruding toward the other axial side from a radially intermediate portion of the other axial side surface (right side surface in FIG. 31) of the side plate portion 103b. That is, the first member 103 has a substantially F-shaped cross section.

[0006] The second member 104 is coupled and fixed to the output member 102 and rotates integrally with the output member 102. The second member 104 has a circular ring portion 104a that is externally fitted and fixed to the output member 102, and a cylindrical portion 104b that is bent from a radially outer end of the circular ring portion 104a toward the other axial side.

[0007] The frictional engagement portion 105 includes a plurality of first friction plates 105a and second friction plates 105b that are alternately stacked in the axial direction. Each of the first friction plates 105a is fitted externally to the large-diameter cylindrical portion 103c of the first member 103 so as to be displaceable in the axial direction but not to rotate relative thereto. Each of the second friction plates 105b is fitted internally to the cylindrical portion 104b of the second member so as to be displaceable in the axial direction but not to rotate relative thereto.

[0008] The cam device 106 includes a drive cam 106a, a cam plate 106b, and a plurality of balls 106c.

[0009] The driving cam 106a has a driving-side cam surface 106a1 on the other axial side surface, and a gear portion 106a2 on the outer circumferential surface. The driving cam 106a is disposed around the input member 101 so as to be capable of relative rotation with respect to the input member 101 and displacement in the axial direction.

[0010] The cam plate 106b has a fixed cam surface 106b1 on one axial side surface. The cam plate 106b is disposed around the input member 101 so as to be capable of rotating relative to the input member 101 but not capable of displacing in the axial direction.

[0011] Each ball 106c is held between a driving side cam surface 106a1 and a fixed side cam surface 106b1 so as to be capable of rolling.

[0012] The electric actuator 107 rotates and drives the drive cam 106a of the cam device 106. The electric actuator 107 has an electric motor 107a and a reducer 107b that increases the output torque of the electric motor 107a and transmits it to the drive cam 106a. For this purpose, an output gear 107b1 of the reducer 107b is meshed with a gear portion 106a2 provided on the outer circumferential surface of the drive cam 106a.

[0013] The pressing member 108 is disposed to face the other axial side of the friction plate located furthest on the other axial side among the plurality of first friction plates 105a and second friction plates 105b, and is supported so as to be movable toward and away from the friction plate located furthest on the other axial side. The pressing member 108 is fitted around the input member 101 so as to be displaceable in the axial direction relative to the input member 101.

[0014] The rolling bearing 109 is disposed between the driving cam 106 a and the pressing member 108 .

[0015] The elastic member 110 is sandwiched between the first member 103 and the pressing member 108 in an elastically compressed state, and elastically biases the pressing member 108 toward the other axial direction. The elastic member 110 is formed of a compression coil spring.

[0016] When the clutch device 100 is switched to the connection mode, the electric actuator 107 rotates the drive cam 106a, and the ball 106c is positioned between the tip face of the convex portion of the drive-side cam surface 106a1 and the tip face of the convex portion of the fixed-side cam surface 106b1, thereby widening the gap between the drive cam 106a and the cam plate 106b and pressing the pressing member 108 toward one side in the axial direction. As a result, the first friction plate 105a and the second friction plate 105b are pressed against each other, connecting the friction engagement portion 105, and the first member 103 and the second member 104 rotate integrally.

[0017] When the clutch device 100 is switched to the disconnection mode, the driving cam 106a is rotationally driven by the electric actuator 107 to position the ball 106c between the bottom of the recess of the driving cam surface 106a1 and the bottom of the recess of the fixed cam surface 106b1, and the pressing member 108 is pressed toward the other axial direction by the force of the elastic member 110 attempting to elastically restore, thereby reducing the gap between the driving cam 106a and the cam plate 106b. As a result, the force pressing the first friction plate 105a and the second friction plate 105b against each other is released, the frictional engagement portion 105 is disconnected, and the first member 103 and the second member 104 are allowed to rotate relative to each other. [Prior art documents] [Patent documents]

[0018] [Patent Document 1] International Publication No. 2008 / 096438 Brochure Summary of the Invention [Problem to be solved by the invention]

[0019] In the clutch device 100 described in WO 2008 / 096438, slippage occurs between the driving side cam surface 106a1 and / or the fixed side cam surface 106b1 and the rolling surface of the ball 106c, and there is a possibility that the amount of lift from the bottom of the recess of the driving side cam surface 106a1 and / or the amount of lift from the bottom of the recess of the fixed side cam surface 106b1 varies between the plurality of balls 106c. If such a variation occurs, there is a possibility that the axial displacement amount of the pressing member 108 cannot be sufficiently secured. As a result, there is a possibility that the fastening force of the friction engagement portion 105 cannot be sufficiently secured when the clutch device 100 is switched to the connection mode, or that the first friction plate 105a and the second friction plate 105b cannot be sufficiently separated when the clutch device 100 is switched to the disconnection mode, causing dragging.

[0020] An object of the present invention is to realize an electric friction clutch structure that can sufficiently and reliably ensure the amount of expansion and contraction of the axial dimension of a cam device. [Means for solving the problem]

[0021] An electric friction clutch device according to one aspect of the present invention includes a first member, a second member, a friction engagement portion, a cam device, an electric actuator, a pressing member, a rolling bearing, and an elastic member.

[0022] The second member is supported coaxially with the first member and capable of relative rotation with respect to the first member.

[0023] The friction engagement portion has at least one, and preferably a plurality of, first and second friction plates supported to allow relative displacement in the axial direction.

[0024] The cam device includes a drive cam, a holder, and a plurality of rolling elements.

[0025] The drive cam has a cam surface on one side surface in the axial direction, and is supported so as to be rotatable relative to a fixed portion which does not rotate even during use, but is unable to move in the axial direction.

[0026] The holder is supported so as to be axially displaceable but not rotatable relative to the fixed portion.

[0027] The rolling element has a rolling surface that is in rolling contact with the cam surface, and is held by the holder.

[0028] The electric actuator rotates the drive cam.

[0029] The pressing member is disposed opposite the other axial side surface of the friction plate which is located furthest on the other axial side among the first friction plate and the second friction plate, and is supported so as to be movable toward and away from the friction plate which is located furthest on the other axial side in the axial direction.

[0030] The rolling bearing is disposed between the holder and the pressing member.

[0031] The elastic member elastically biases the pressing member toward the other axial direction.

[0032] In one embodiment of the electric friction clutch device of the present invention, by driving the drive cam to rotate with the electric actuator, the holder is displaced in a direction that increases the distance between the drive cam and the first friction plate and the second friction plate are pressed against each other, thereby switching to a connection mode in which the first member and the second member rotate together, and by displacing the holder in a direction that decreases the distance between the drive cam and the first friction plate and the second friction plate, the force pressing the first friction plate and the second friction plate against each other is released, thereby switching to a disconnection mode in which the first member and the second member rotate relative to each other.

[0033] In an electric friction clutch device according to one aspect of the present invention, The rolling elements may have a cylindrical shape, and The cam device can include a plurality of support shafts, each of which has both axial ends supported in the holder, and rollers, each of which is freely rollably arranged between the inner surface of the rolling body and the outer surface of the support shaft.

[0034] In the electric friction clutch device according to one aspect of the present invention, the cam device may include a retaining member that prevents the support shaft from being displaced in the axial direction of the support shaft relative to the holder.

[0035] In the electric friction clutch device according to one aspect of the present invention, the first member may have a first cylindrical portion. In this case, the first friction plate may be supported on an outer circumferential surface of the first cylindrical portion, and the elastic member, a part of the pressing member, and the rolling bearing may be disposed radially inside the first cylindrical portion.

[0036] In one embodiment of the electric friction clutch device of the present invention, the first member can include a flange member having a first cylindrical portion and a circular ring portion bent radially inward from one axial end of the first cylindrical portion, and a shaft body joined and fixed to the inner peripheral surface of the circular ring portion, and the first friction plate can be supported on the outer peripheral surface of the first cylindrical portion.

[0037] In the electric friction clutch device according to one aspect of the present invention, the flange member may be a pressed product, and the shaft body may be a forged product.

[0038] In the electric friction clutch device according to one aspect of the present invention, the first member may include a retaining ring engaged with an outer circumferential surface of the first cylindrical portion. In this case, the first friction plate can be supported on the outer circumferential surface of the first cylindrical portion so as to be capable of axial displacement, and the retaining ring can prevent the first friction plate from being displaced to one side in the axial direction.

[0039] In the electric friction clutch device according to one aspect of the present invention, the elastic member may be formed of a disc spring.

[0040] In the electric friction clutch device according to one aspect of the present invention, the drive cam and / or the holder can be made of sintered metal.

[0041] In the electric friction clutch device according to one aspect of the present invention, the cam device may include a biasing member that elastically biases the drive cam in a direction in which the distance between the drive cam and the holder decreases. Alternatively, in the electric friction clutch device according to one aspect of the present invention, the electric actuator may include a biasing member that elastically biases the drive cam in a direction that reduces the distance between the drive cam and the holder. Effect of the Invention

[0042] According to an electric friction clutch device according to an aspect of the present invention, the amount of expansion / contraction in the axial direction of the cam device can be sufficiently and reliably ensured. [Brief description of the drawings]

[0043] [Figure 1] FIG. 1 is an end view of an electric friction clutch device according to a first embodiment of the present invention, as viewed from one axial side. [Diagram 2] FIG. 2 is an end view of the electric friction clutch device of the first example, as viewed from the other axial side. [Diagram 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. [Figure 4] FIG. 4 is an exploded perspective view showing the electric friction clutch device of the first example. [Diagram 5] FIG. 5 is a perspective view of the electric friction clutch device of the first example, seen from one axial side with the second member omitted. [Figure 6] FIG. 6 is a perspective view of the electric friction clutch device of the first example, seen from the other axial side with the second member omitted. [Figure 7] FIG. 7 is a perspective view showing the first member. [Figure 8] FIG. 8 is a cross-sectional view showing the first member. [Figure 9] FIG. 9 is a perspective view showing the fixing member. [Figure 10] FIG. 10 is a side view showing the cam device with the distance between the drive cam and the holder reduced. [Figure 11] FIG. 11 is a side view showing the cam device with the distance between the drive cam and the holder expanded. [Figure 12] FIG. 12 is a perspective view showing the drive cam. [Figure 13] FIG. 13 is a perspective view showing the drive cam and the worm. [Figure 14] FIG. 14 is a perspective view showing the holder and the rolling elements in an assembled state. [Figure 15] FIG. 15 is an end view of the holder and rolling elements assembled together, as viewed from the other axial side. [Figure 16] FIG. 16 is a cross-sectional view taken along line BB of FIG. [Figure 17]FIG. 17 is an exploded perspective view showing the portion where the rolling elements are assembled to the holder. [Figure 18] FIG. 18 is an end view showing the frictional engagement portion. [Figure 19] FIG. 19 is a cross-sectional view taken along line CC of FIG. [Figure 20] FIG. 20 is an exploded perspective view showing the frictional engagement portion. [Figure 21] FIG. 21 is a perspective view showing another example of the support shaft. [Figure 22] FIG. 22 is a diagram showing the relationship between the rotation angle of the drive cam and the amount of axial displacement in the modified example of the first example. [Figure 23] FIG. 23 is a half sectional view showing an electric friction clutch device according to a second embodiment of the present invention. [Figure 24] FIG. 24 is a perspective view showing the end plate. [Diagram 25] FIG. 25 is a cross-sectional view showing an electric friction clutch device according to a third embodiment of the present invention. [Figure 26] FIG. 26(A) is a perspective view of the nut as viewed from one axial side, and FIG. 26(B) is a perspective view of the nut as viewed from the other axial side. [Figure 27] FIG. 27 is an end view showing a reducer taken out from an electric friction clutch device according to a fourth embodiment of the present invention. [Figure 28] FIG. 28 is a perspective view showing a reducer taken out from an electric friction clutch device according to a fifth embodiment of the present invention. [Figure 29] FIG. 29 is a cross section showing the assembly portion of the power spring. [Diagram 30] FIG. 30 is an exploded perspective view showing an assembly portion of the power spring. [Diagram 31] FIG. 31 is a cross-sectional view showing an example of a clutch device having a conventional structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] [Example 1] 1 to 20 show a first embodiment of the present invention. An electric friction clutch device 1 of this embodiment includes a first member 2, a second member 3, a friction engagement portion 4, a cam device 5, an electric actuator 6, a pressing member 7, a rolling bearing 8, and an elastic member 9.

[0045] The electric friction clutch device 1 is disposed, for example, in a portion of the drive system of an automobile between a drive source such as an electric motor or an engine and a transmission, or between the transmission and a differential. However, the electric friction clutch device of the present invention can be disposed between a pair of rotating members or between a rotating member and a fixed member in various mechanical devices, regardless of the drive system of an automobile.

[0046] In the following description, unless otherwise specified, the axial direction, radial direction, and circumferential direction refer to the axial direction, radial direction, and circumferential direction of the first member 2. Moreover, one axial side refers to the left side in Fig. 3, and the other axial side refers to the right side in Fig. 3.

[0047] The first member 2 is rotatably supported by a fixed member 10 that does not rotate even during use. The first member 2 is connected to a first rotating member 72 (see FIG. 4) such as an output shaft of a drive source or an output shaft of a transmission so as to be able to transmit torque.

[0048] As shown in FIG. 9, the fixed member 10 includes a fixed cylindrical portion 11 and a flange portion 12 bent radially outward from the other axial end of the fixed cylindrical portion 11.

[0049] The fixed cylinder portion 11 has a male spline portion 13 on the outer circumferential surface at one end in the axial direction.

[0050] The flange portion 12 has through holes 70 penetrating in the axial direction at one or more locations (one location in the illustrated example) in the circumferential direction.

[0051] The fixed member 10 is supported and fixed to a fixed portion such as a housing by a fastening member such as a bolt or pin inserted into a through hole 70 of the flange portion 12, and does not rotate or displace during use.

[0052] As shown in FIGS. 7 and 8, the first member 2 includes a flange member 14 and a shaft body 15.

[0053] The flange member 14 has a first tubular portion 16 and a circular ring portion 17 bent radially inward from one axial end of the first tubular portion 16. In this example, the flange member 14 is made by pressing a metal plate having sufficient strength and rigidity, such as a steel plate, and then nitriding the surface.

[0054] The first cylindrical portion 16 has, on its outer circumferential surface, an inner diameter side concave-convex portion 18 in which concave portions and convex portions are alternately arranged in the circumferential direction.

[0055] Shaft body 15 is joined and fixed to the inner circumferential surface of circular ring portion 17 of flange member 14. In this example, shaft body 15 has a stepped cylindrical shape. Specifically, shaft body 15 is constructed by connecting a large-diameter cylindrical portion 19 on one axial side and a small-diameter cylindrical portion 20 on the other axial side by a hollow circular plate-like side plate portion 21. In this example, shaft body 15 is made by forging a hard metal material such as medium carbon steel, and then nitriding the surface.

[0056] The small diameter cylindrical portion 20 has a locking groove 22 formed around the entire circumference on the outer circumferential surface of the other axial side portion, and has a female spline portion 71 on the inner circumferential surface at the end portion on the other axial side.

[0057] In this example, the first member 2 is constructed by fitting one axial end of the large-diameter cylindrical portion 19 of the shaft body 15 into the circular ring portion 17 of the flange member 14, and by joining and fixing the flange member 14 and the shaft body 15 to each other by welding. The first member 2 is connected to the first rotating member 72 so as to be able to transmit torque by spline-engaging the male spline portion 73 of the first rotating member 72 with the female spline portion 71.

[0058] The first member 2 is rotatably supported with respect to the fixed member 10 by a radial rolling bearing 23 .

[0059] The radial rolling bearing 23 includes an inner ring 24, an outer ring 25, and a plurality of rolling elements 26 disposed between the inner ring 24 and the outer ring 25 so as to be freely rollable.

[0060] The inner ring 24 is fitted onto one axial side portion of the small diameter cylindrical portion 20 and is axially sandwiched between the other axial side surface of the side plate portion 21 and a retaining ring 27 engaged in the engaging groove 22.

[0061] The outer ring 25 is fitted into the other axial side portion of the fixed cylindrical portion 11 and is provided on the inner surface of the axial middle portion of the fixed cylindrical portion 11, and is axially clamped between a step surface 28 facing the other axial side and a retaining ring 29 engaged with the inner surface of the end portion on the other axial side of the fixed cylindrical portion 11.

[0062] The radial rolling bearing 23 in this example is configured as a single-row angular ball bearing that uses balls as the rolling elements 26 and has a contact angle. However, the radial rolling bearing for supporting the first member rotatably relative to the fixed member is not particularly limited as long as it can support radial and thrust loads, and can also be configured as a single-row deep groove ball bearing or a tapered roller bearing.

[0063] The second member 3 is supported coaxially with the first member 2 and capable of relative rotation with respect to the first member 2. The second member 3 is connected to a second rotating member (not shown) such as an input shaft of a transmission or an input shaft of a differential device so as to be capable of transmitting torque. In this example, the second member 3 has a second tubular portion 30.

[0064] The second cylindrical portion 30 has an outer diameter side concave-convex portion 31 on its inner circumferential surface, the outer diameter side concave-convex portion 31 being formed by alternately arranging concave and convex portions in the circumferential direction.

[0065] The friction engagement portion 4 has at least one each, and preferably multiple each, of first friction plates 32 and second friction plates 33, which are supported so as to be capable of relative axial displacement. In this example, the friction engagement portion 4 is formed by alternately stacking six first friction plates 32 and five second friction plates 33.

[0066] Each of the first friction plates 32 is configured in a substantially hollow circular plate shape. Each of the first friction plates 32 has an outer diameter side uneven portion 34 on its inner circumferential surface, in which recesses and protrusions are alternately arranged in the circumferential direction. Each of the first friction plates 32 is supported with respect to the first cylindrical portion 16 so as to be capable of axial displacement but not capable of relative rotation by engaging the outer diameter side uneven portion 34 with the inner diameter side uneven portion 18 of the first member 2.

[0067] Of the six first friction plates 32, the first friction plate 32 located furthest to one side in the axial direction is prevented from being displaced to that side in the axial direction by a retaining ring 35 engaged with the outer peripheral surface of the one axial side portion of the first tubular portion 16.

[0068] Each of the second friction plates 33 is configured in a substantially hollow circular plate shape. Each of the second friction plates 33 has an inner diameter side uneven portion 36 on its outer circumferential surface, in which concave and convex portions are alternately arranged in the circumferential direction. Each of the second friction plates 33 is supported by engaging the inner diameter side uneven portion 36 with the outer diameter side uneven portion 31 of the second member 3, so as to be capable of axial displacement with respect to the second cylindrical portion 30 but not capable of relative rotation.

[0069] The friction engagement portion 4 may include a return spring that elastically biases the first friction plate 32 and the second friction plate 33 in a direction separating them from each other.

[0070] The cam device 5 includes a drive cam 37, a holder 38, and a plurality of rolling elements 39 (three in the illustrated example).

[0071] The drive cam 37 has a cam surface 40, which is an uneven surface in the circumferential direction, on one side surface in the axial direction, and a gear portion 41 on a part of the outer circumferential surface in the circumferential direction. In this example, the drive cam 37 has a main body portion 42 configured in a hollow circular shape, and a substantially sector-shaped protrusion portion 43 protruding radially outward from one circumferential point of the main body portion 42.

[0072] The cam surface 40 is provided on one axial side surface of the main body portion 42. The cam surface 40 is configured by repeatedly arranging a bottom portion 44, an inclined surface portion 45a, a flat surface portion 46, and an inclined surface portion 45b in this order multiple times (three times in the illustrated example). Of the cam surface 40, the flat surface portion 46 is located closest to one axial side, and the bottom portion 44 is located closest to the other axial side. The inclined surface portion 45a and the inclined surface portion 45b are inclined in opposite directions, and have the same absolute value of the inclination angle with respect to a virtual plane perpendicular to the central axis of the drive cam 37.

[0073] The gear portion 41 is provided on the radially outer surface of the protruding portion 43 .

[0074] The drive cam 37 is supported by a radial rolling bearing 47 so as to be rotatable relative to the fixed member 10 but not to be displaced in the axial direction. The radial rolling bearing 47 is disposed between the inner peripheral surface of the main body portion 42 and the outer peripheral surface of the other axial end of the fixed cylinder portion 11.

[0075] The radial rolling bearing 47 includes an inner ring 48, an outer ring 49, and a plurality of rolling elements 50 disposed between the inner ring 48 and the outer ring 49 so as to be capable of rolling freely.

[0076] The inner ring 48 is fitted onto the other axial end of the fixed cylindrical portion 11 , and the other axial side surface of the inner ring 48 abuts against one axial side surface of the flange portion 12 .

[0077] The outer ring 49 is fitted inside the main body portion 42, and one side surface in the axial direction is abutted against a step surface 51 that is provided on the inner peripheral surface of the main body portion 42 and faces the other axial side.

[0078] Radial rolling bearing 47 uses balls as rolling elements 50 and is configured as a single-row angular ball bearing having a contact angle. However, the radial rolling bearing for supporting the drive cam rotatably relative to the fixed member is not particularly limited as long as it can support radial and thrust loads, and can also be configured as a single-row deep groove ball bearing, tapered roller bearing, etc.

[0079] The holder 38 is supported relative to the fixed member 10 so as to be unable to rotate but to be movable in the axial direction. For this purpose, the holder 38 has a female spline portion 52 on its inner circumferential surface. The female spline portion 52 of the holder 38 is spline-engaged with the male spline portion 13 of the fixed member 10 so as to be movable relative to the male spline portion 13 in the axial direction.

[0080] 14 to 17, holder 38 is configured in a hollow circular plate shape and has rectangular holes 53 penetrating in the axial direction at a plurality of circumferential positions (three positions in the illustrated example) in a radially intermediate portion, and has support plate portions 54a, 54b in the shape of approximately semicircular plates protruding toward the other axial side from both radial sides of rectangular hole 53. Support plate portions 54a, 54b each have support holes 55a, 55b which are circular holes penetrating in the radial direction.

[0081] Each rolling body 39 has a rolling surface 69 on its outer circumferential surface that is in rolling contact with the cam surface 40, and is held in the holder 38 so as to be freely rotatable (spinning) around its own central axis (rotation axis) C arranged in a radial direction around the central axis of the holder 38.

[0082] In this example, each rolling element 39 has a cylindrical shape and is rotatably supported by the holder 38 by a columnar support shaft 57 and a plurality of rollers 58. Specifically, the rolling elements 39 are arranged around an axial middle portion of the support shaft 57 (a middle portion of the support shaft 57 in the radial direction centered on the central axis of the holder 38), and the rollers 58 are arranged to roll freely between the outer circumferential surface of the support shaft 57 and the inner circumferential surface of the rolling elements 39. In addition, both ends of the support shaft 57 in the axial direction, i.e., both ends of the support shaft 57 in the radial direction centered on the central axis of the holder 38, are fitted into the support holes 55a, 55b of the support plate portions 54a, 54b.

[0083] Furthermore, in this example, the cam device 5 includes a retaining member 60 that prevents the support shaft 57 from being displaced in the axial direction of the support shaft 57 (radial direction about the central axis of the holder 38) relative to the holder 38. In this example, the retaining member 60 is configured by a cylindrical pin. The retaining member 60 is press-fitted into a through hole 59 that passes through the inner portion of the support shaft 57 in the radial direction of the holder 38 in the axial direction of the holder 38, and into a locking hole 56 that passes through the support plate portion 54a on the radial inner side of the holder 38 in the axial direction of the holder 38. This prevents the support shaft 57 from being displaced relative to the holder 38.

[0084] In addition, when carrying out the present invention, the shape of the retaining member, the engagement of the retaining member with the holder and the support shaft, etc. are not limited to the embodiment of this example, and can be determined arbitrarily. For example, as shown in Fig. 21, a locking groove 79 can be formed around the entire circumference of the support shaft 57a on the inner side in the radial direction of the holder 38, and the middle part of the retaining member 60 press-fitted into the locking hole 56 can be disposed inside the locking groove 79, thereby preventing the support shaft 57a from being displaced with respect to the holder 38. According to the other example shown in Fig. 21, when the support shaft 57a is assembled to the holder 38, it is not necessary to align the phase of the support shaft 57a in the rotational direction, and the assembly cost can be reduced.

[0085] With the rolling elements 39 held in the holder 38 so as to be free to rotate (spin) about the rotation axis C, one axial side portion of the rolling elements 39 is disposed inside the rectangular hole 53. Also, each of the rolling elements 39 has a rolling surface 69 provided on its outer circumferential surface in rolling contact with a cam surface 40 provided on one axial side surface of the drive cam 37.

[0086] In the cam device 5, as the driving cam 37 rotates, the amount by which the rolling elements 39 ride up from the bottom 44 of the cam surface 40 increases or decreases, so that the holder 38 is displaced in the axial direction.

[0087] Although there is no particular limitation on the materials constituting the drive cam 37, holder 38, and rolling element 39, for example, the drive cam 37 and / or holder 38 can be integrally formed from sintered metal, which allows the drive cam 37 and / or holder 38 having a complex shape to be manufactured at low cost.

[0088] The electric actuator 6 rotates the drive cam 37. In this example, the electric actuator 6 includes an electric motor (not shown) and a reducer 61. The reducer 61 is configured by meshing a worm 62, which is rotated by the electric motor, with a gear portion 41 provided on the outer circumferential surface of the drive cam 37.

[0089] The pressing member 7 faces the friction plate which is located furthest on the other axial side among the first friction plate 32 and the second friction plate 33, i.e., the first friction plate 32 which is furthest on the other axial side in this example, and is arranged so as to be able to move axially toward and away from the first friction plate 32 which is furthest on the other axial side.

[0090] In this example, the pressing member 7 is formed by bending a metal plate having sufficient strength and rigidity, such as a steel plate, into a generally crank-shaped cross section. Specifically, the pressing member 7 has a hollow circular plate-like side plate portion 63, a cylindrical portion 64 bent from a radially outer end of the side plate portion 63 toward one side in the axial direction, and a pressing plate portion 65 bent from the other axial end of the cylindrical portion 64 toward the radially outer side.

[0091] Side plate portion 63 is fitted onto first member 2 so as to allow relative axial displacement. Specifically, side plate portion 63 is fitted onto one axial side portion of large diameter cylindrical portion 19 of shaft body 15 without rattle and so as to allow relative axial displacement. Thus, pressing member 7 is supported onto first member 2 so as to allow relative axial displacement.

[0092] The pressing plate portion 65 has a generally S-shaped cross section, with one axial side surface of a radially outer portion opposed to the other axial side surface of the first friction plate 32 located on the other axial side furthest to the other axial side.

[0093] The rolling bearing 8 is disposed between the holder 38 and the pressing member 7 .

[0094] In this example, the rolling bearing 8 is configured as a single-row angular contact ball bearing capable of supporting radial loads and thrust loads. That is, the rolling bearing 8 includes an outer ring 66, an inner ring 67, and balls 68 arranged to roll freely between the outer ring 66 and the inner ring 67. The rolling bearing 8 is sandwiched between one axial side surface of the holder 38 and the other axial side surface of the side plate portion 63 of the pressing member 7. In other words, one axial side surface of the outer ring 66 abuts against the other axial side surface of the side plate portion 63, and the other axial side surface of the inner ring 67 abuts against one axial side surface of the holder 38.

[0095] The elastic member 9 elastically biases the pressing member 7 toward the other axial side, which is a direction in which the force pressing the first friction plate 32 and the second friction plate 33 against each other is released. For this reason, the elastic member 9 is sandwiched between the pressing member 7 and the first member 2 in an elastically compressed state. As a result, the holder 38 is elastically pressed toward the other axial side, which is a direction in which the axial distance between the holder 38 and the drive cam 37 decreases, via the pressing member 7 and the rolling bearing 8, and a preload is applied to the rolling element 39 of the cam device 5 and the rolling bearings 8, 23, 47, preventing harmful slippage from occurring at the rolling contact portions.

[0096] In this example, the elastic member 9 is configured by combining two disc springs in series with their small diameter ends facing each other. However, the elastic member can also be configured by combining two disc springs in series with their large diameter ends facing each other. Alternatively, the elastic member can be configured by one disc spring or three or more disc springs.

[0097] In the electric friction clutch device 1 of this example, the elastic member 9, a portion of the pressing member 7, and the rolling bearing 8 are arranged radially inside the first cylindrical portion 16 of the first member 2, regardless of the axial dimension of the cam device 5.

[0098] In this example, even when the rolling element 39 is located at the bottom 44 and the axial dimension of the cam device 5 is at its smallest, the elastic member 9, one axial side portion and side plate portion 63 of the tubular portion 64 of the pressing member 7, the rolling bearing 8, and one axial side portion of the holder 38 are located radially inside the first tubular portion 16. More specifically, in the electric friction clutch device 1 of this example, the rolling bearing 8 and one axial side portion of the holder 38 are disposed radially inside the tubular portion 64 of the pressing member 7, and the first tubular portion 16 is disposed around the one axial side portion and side plate portion 63 of the tubular portion 64, and the elastic member 9.

[0099] The electric friction clutch device 1 of this example switches between a connection mode in which the first member 2 and the second member 3 rotate together and a disconnection mode in which the first member 2 and the second member 3 rotate relative to each other, based on the electric actuator 6 rotating the drive cam 37 of the cam device 5.

[0100] To switch the electric friction clutch device 1 to the connection mode, the driving cam 37 is rotated to position the rolling body 39 on the flat surface portion 46 or to increase the amount of riding on the inclined surface portion 45a (or 45b). As a result, the holder 38 is displaced toward one axial side in the direction in which the axial distance from the driving cam 37 increases, and the pressing member 7 and the rolling bearing 8 are pressed toward one axial side against the elasticity of the elastic member 9. Furthermore, the pressing member 7 presses the first friction plate 32, which is the most axially opposite side, toward one axial side against the elasticity of the elastic member 9 and the return spring. As a result, the first friction plate 32 and the second friction plate 33 are pressed against each other to connect the friction engagement portion 4, and the first member 2 and the second member 3 rotate integrally.

[0101] On the other hand, to switch the electric friction clutch device 1 to the disconnection mode, the driving cam 37 is rotated to position the rolling body 39 at the bottom 44 or to reduce the amount of riding on the inclined surface portion 45a (or 45b). This displaces the holder 38 toward the other axial side in the direction in which the axial distance from the driving cam 37 is reduced, thereby reducing the force pressing the pressing member 7 toward one axial side. When the force pressing the pressing member 7 toward one axial side is reduced, the pressing member 7 and the rolling bearing 8 are pressed toward the other axial side mainly by the elastic restoring force of the elastic member 9. As a result, the force pressing the first friction plate 32 and the second friction plate 33 against each other is reduced by the action of the return spring, and finally, a gap is formed between the first friction plate 32 and the second friction plate 33, and the force pressing the first friction plate 32 and the second friction plate 33 against each other is lost, that is, released. As a result, by cutting the frictional engagement portion 4, the first member 2 and the second member 3 become capable of rotating relative to each other.

[0102] If the power supply to the electric actuator 6 is stopped while the rolling element 39 is positioned midway on the inclined surface portion 45a (or 45b), the elastic restoring force of the elastic member 9 presses the pressing member 7 and the rolling bearing 8 toward the other axial direction, and the force pressing the first friction plate 32 and the second friction plate 33 against each other is released. This allows the frictional engagement portion 4 to be cut off.

[0103] In the electric friction clutch device 1 of this example, the multiple rolling elements 39 constituting the cam device 5 are held in a holder 38 so as to be rotatable about their own axes. Therefore, even if slippage occurs between the cam surface 40 of the drive cam 37 and the rolling surface 69 of the rolling elements 39, there is no variation in the amount of overriding from the bottom 44 of the cam surface 40 between the multiple rolling elements 39. Therefore, the amount of axial displacement of the holder 38 can be sufficiently and reliably ensured, and the amount of expansion and contraction of the axial dimension of the cam device 5 can be sufficiently and reliably ensured.

[0104] Therefore, when the electric friction clutch device 1 is switched to the connection mode, a sufficient pressing force between the first friction plate 32 and the second friction plate 33 can be ensured, and a sufficient fastening force can be ensured for the friction engagement portion 4. Furthermore, when the electric friction clutch device 1 is switched to the disconnection mode, the first friction plate 32 and the second friction plate 33 can be sufficiently separated from each other, that is, a gap can be reliably formed between the first friction plate 32 and the second friction plate 33, thereby preventing the occurrence of drag.

[0105] In this example, a roller having a cylindrical shape is used as the rolling element 39. Therefore, compared to the conventional structure shown in FIG. 31 in which balls 106c are used as the rolling elements of the cam device 106, the occurrence of slippage can be suppressed.

[0106] Furthermore, in the electric friction clutch device 1 of this embodiment, a retaining member 60 is press-fitted into a through hole 59 penetrating one axial side portion of the support shaft 57 and into a locking hole 56 penetrating axially through the support plate portion 54b on the radially inner side of the holder 38. This makes it possible to prevent the support shaft 57 from being accidentally displaced relative to the holder 38 in its axial direction (radial direction centered on the central axis of the holder 38).

[0107] According to the electric friction clutch device 1 of this embodiment, the manufacturing costs of the first member 2 that supports the first friction plate 32 and is connected to the first rotating member 72 can be reduced.

[0108] In the clutch device 100 having a conventional structure shown in Fig. 31, a first member 103 including a small diameter cylindrical portion 103a fitted and fixed to the input member 101 and a large diameter cylindrical portion 103c onto which a first friction plate 105a is fitted to allow axial displacement is formed as a whole. If an attempt is made to manufacture the first member 103 having such a substantially F-shaped cross section by forging, the processing load becomes large, which may increase the manufacturing cost.

[0109] In contrast, in this embodiment, the first member 2, which has the first tubular portion 16 that supports the first friction plate 32 and is connected to the first rotating member 72, is constructed by joining and fixing the flange member 14, which is a pressed product, and the shaft body 15, which is a forged product. This makes it possible to reduce the manufacturing cost of the first member 2.

[0110] 31, the pressing member 108, the rolling bearing 109, and the drive cam 106a are arranged side by side between the first member 103 and the cam plate 106b in the axial direction. Therefore, the clutch device 100 with the conventional structure has a large axial dimension.

[0111] In contrast to this, in this example, the elastic member 9, a part of the pressing member 7, and the rolling bearing 8 are disposed radially inside the first cylindrical portion 16 of the first member 2, regardless of the axial dimension of the cam device 5. Therefore, according to the electric friction clutch device 1 of this example, the axial dimension can be reduced compared to the clutch device 100 of the conventional structure.

[0112] In this example, the pressing plate portion 65 of the pressing member 7 has a substantially S-shaped cross section. That is, the portion of the pressing member 7 that presses the other axial side surface of the first friction plate 32 on the other axial side at the furthest side in the axial direction is configured with a convex curved surface. This makes it possible to prevent excessive sensitivity to changes in the pressing force of the pressing member 7 that change in accordance with the axial displacement of the holder 38, and improves the controllability of the electric friction clutch device 1.

[0113] In this embodiment, the elastic member 9 is made of a disc spring, so the axial dimension is easier to reduce compared to when a compression coil spring is used as the elastic member that elastically presses the pressing member toward the other axial direction. Also, because the disc spring has nonlinear spring characteristics, it is possible to prevent excessive load from being applied to the rolling bearings 8, 23, 47 and the meshing portion between the gear portion 41 and the worm 62, and to improve durability. However, when implementing the present invention, a compression coil spring can also be used as the elastic member.

[0114] In this example, the inclined surface portions 45a and 45b of the cam surface 40 of the drive cam 37 are formed of planes having a constant inclination angle with respect to a virtual plane perpendicular to the central axis of the drive cam 37. However, when implementing the present invention, as shown in FIG. 22, the inclined surface portion connecting the bottom portion and the flat surface portion of the cam surface may be formed of a plurality of flat surfaces and / or curved surfaces. Specifically, in an initial state before the first and second friction plates are worn, the rolling element climbs up the inclined surface portion from the bottom portion, and as the holder moves toward one axial side, the pressing member moves toward one axial side, and the pressing member contacts the other axial side surface of the friction plate that is the most axially opposite of the first and second friction plates (initial piston touch point), the inclination angle of the inclined surface portion can be made relatively large so that the amount of axial displacement of the holder relative to the rotation angle of the drive cam is large, that is, the time until the initial piston touch point is reached can be shortened. In contrast, after the initial piston touch point is exceeded, the inclination angle of the inclined surface portion can be made relatively small in order to ensure good controllability of the fastening force of the frictional engagement portion by the pressing member. Also, the formation range of the gear portion provided on the outer circumferential surface of the drive cam can be made small, thereby reducing manufacturing costs.

[0115] [Example 2] 23 and 24 show a second embodiment of the present invention. In the electric friction clutch device 1a of this embodiment, the friction engagement portion 4a is formed by alternately stacking five first friction plates 32 and five second friction plates 33.

[0116] The electric friction clutch device 1a of this embodiment includes an end plate 74 having a substantially L-shaped cross section.

[0117] End plate 74 has a hollow circular plate portion 75 and a protruding portion 76 protruding around the entire circumference from a radially outer portion of one axial side surface of plate portion 75 toward one axial side. Plate portion 75 has an outer diameter side concave-convex portion 77 on its inner circumferential surface, in which concave portions and convex portions are alternately arranged in the circumferential direction.

[0118] The end plate 74 is fitted onto the first cylindrical portion 16 so as to be unable to rotate relative to it, by engaging the outer diameter side uneven portion 77 with the inner diameter side uneven portion 18 provided on the outer peripheral surface of the first cylindrical portion 16 of the first member 2. The end plate 74 has the inner peripheral surface of the convex portion 76 in contact with or closely facing the outer peripheral surface of the retaining ring 35, and has one axial side surface of the radially inner surface of the plate portion 75 in contact with the other axial side surface of the retaining ring 35.

[0119] In this example, of the first friction plate 32 and the second friction plate 33, the second friction plate 33 located furthest on one axial side is opposed to a retaining ring 35 engaged with the first tubular portion 16 via an end plate 74, thereby preventing the second friction plate 33 located furthest on one axial side from being displaced to one axial side.

[0120] In the electric friction clutch device 1 of this example, the inner peripheral surface of the protrusion 76 of the end plate 74 fitted onto the first cylindrical portion 16 is in contact with or closely opposed to the outer peripheral surface of the retaining ring 35. Therefore, even if centrifugal force is applied to the retaining ring 35 as the first member 2 rotates and the retaining ring 35 tries to lift up, it is possible to prevent the retaining ring 35 from accidentally falling off the first cylindrical portion 16. The configuration and effects of the other parts are the same as those of the first example.

[0121] [Example 3] 25 to 26(B) show a third embodiment of the present invention. In an electric friction clutch device 1b of this embodiment, an inner ring 24 of a radial rolling bearing 23 for rotatably supporting a first member 2a relative to a fixed member 10 is axially sandwiched between the other axial side surface of a side plate portion 21 of the first member 2a and a nut 78 screwed into the other axial end portion of the small diameter cylindrical portion 20a.

[0122] According to this example, even if the rotation speed of the first member 2 is high, it is possible to reliably prevent the inner ring 24 of the radial rolling bearing 23 from shifting in the axial direction relative to the small diameter cylindrical portion 20a. The configurations and effects of the other parts are similar to those of the first and second examples.

[0123] [Example 4] Fig. 27 shows a fourth embodiment of the present invention. In this example, the cam device 5 (see Fig. 3, etc.) includes a biasing member 80 that elastically biases the drive cam 37 in a direction that reduces the distance between the drive cam 37 and the holder 38. In this example, the biasing member 80 is provided on a fixed portion 81 that does not rotate even during use, and is configured of a torsion coil spring that is elastically sandwiched between a stepped surface 82 facing in the circumferential direction and one of the side surfaces on both circumferential sides of the protruding portion 43 of the drive cam 37 that faces the stepped surface 82.

[0124] The other circumferential side of the protruding portion 43 faces a stopper surface 83 provided on the fixed portion 81. This prevents the drive cam 37 from rotating excessively toward the other circumferential side when the electric actuator 6 is de-energized.

[0125] According to this example, the elastic restoring force of the elastic member 9 (see FIG. 3, etc.) that elastically biases the pressing member 7 toward the other axial side can be made smaller than that of the electric friction clutch device 1 of the first example. Therefore, it is possible to prevent the preload applied from the elastic member 9 to the rolling elements 39 and the rolling bearings 8, 23, 47 of the cam device 5 from becoming excessive, and it is possible to improve the durability of the cam device 5 and the rolling bearings 8, 23, 47.

[0126] The elasticity of the biasing member 80 is appropriately set so that when the electric actuator 6 is de-energized, the drive cam 37 can be rotated in a direction to reduce the distance between the drive cam 37 and the holder 38, and so that the force required to rotate the drive cam 37 in a direction to increase the distance between the drive cam 37 and the holder 38 in order to connect the frictional engagement portion 4 (see FIG. 3) is not excessively large. The configurations and effects of the other parts are the same as those of the first example.

[0127] [Example 5] 28 to 30 show a fifth embodiment of the present invention. In this embodiment, the electric actuator 6 (see FIG. 3, etc.) includes a biasing member 80a that elastically biases the drive cam 37 in a direction that reduces the distance between the drive cam 37 and the holder 38. In this embodiment, the biasing member 80a is configured by a power spring provided between a fixed portion 81a that does not rotate even when in use and a worm 62a. That is, the biasing member 80a applies elastic force to the worm 62a in a direction that rotates the worm 62a in a predetermined direction, and thereby elastically biases the drive cam 37 in a direction that reduces the distance between the drive cam 37 and the holder 38 via the meshing portion between the worm 62a and the gear portion 41.

[0128] The worm 62a has slits 84 at its base end, the slits 84 opening at two radially opposite positions on its outer circumferential surface and at the base end surface. The slits 84 have a narrow portion 85 on the inner end side and a wide portion 86 on the base end side.

[0129] The biasing member 80a formed of a power spring has a locking piece 87a provided at an end portion on the inner side in the radial direction (on the core side) locked to a narrow portion 85 of a slit 84 of the worm 62a, and a locking piece 87b provided at an end portion on the outer side in the radial direction locked to a locking portion 88 formed on the fixed portion 81a. As a result, the biasing member 80a is stretched between the fixed portion 81a and the worm 62a.

[0130] In this example, a connecting protrusion 90 having a two-face width shape is provided at the tip of an output shaft 89 of an electric motor that constitutes the electric actuator 6 (see Figure 3), and engages with the wide portion 86 of the slit 84 of the worm 62a, thereby connecting the worm 62a and the output shaft 89 and preventing the locking piece 87a of the biasing member 80a from falling off from the slit 84.

[0131] According to this example, similar to the structure of the fourth example, the elastic restoring force of the elastic member 9 (see FIG. 3, etc.) that elastically biases the pressing member 7 toward the other axial side can be made smaller than that of the electric friction clutch device 1 of the first example. Therefore, it is possible to prevent the preload applied from the elastic member 9 to the rolling element 39 and the rolling bearings 8, 23, 47 of the cam device 5 from becoming excessive, and it is possible to improve the durability of the cam device 5 and the rolling bearings 8, 23, 47.

[0132] The elasticity of the biasing member 80a is appropriately set so that when the electric actuator 6 is de-energized, the drive cam 37 can be rotated in a direction that reduces the distance between the drive cam 37 and the holder 38, and so that when the frictional engagement portion 4 (see FIG. 3) is connected, the force required for the electric actuator 6 to rotate the worm 62a in the direction opposite to the predetermined direction is not excessively large. The configurations and effects of the other parts are the same as those of the first and fourth examples. [Explanation of symbols]

[0133] 1, 1a, 1b Electric friction clutch device 2, 2a First member 3 Second member 4, 4a Friction engagement portion 5 Cam device 6 Electric Actuators 7 Pressing member 8. Rolling Bearings 9 Elastic Members 10 Fixing member 11 Fixed cylinder part 12 Flange 13 Male spline part 14 Flange member 15 Axis body 16 First cylinder part 17 Circular part 18 Inner diameter uneven part 19 Large diameter cylinder 20, 20a Small diameter cylinder 21 Side plate part 22 Locking groove 23 Radial Rolling Bearing 24 Inner Circle 25 Outer ring 26 Rolling elements 27 Retaining ring 28 Step surface 29 Retaining ring 30 Second cylinder part 31 Outer diameter side uneven part 32 1st friction plate 33 Second friction plate 34 Outer diameter side unevenness 35 Retaining ring 36 Inner diameter uneven part 37 Drive Cam 38 Holder 39 Rolling elements 40 Cam surface 41 Gear section 42 Main body 43 Protrusion 44 Bottom 45a, 45b Slope section 46 Flat surface section 47 Radial Rolling Bearing 48 Inner Circle 49 Outer Ring 50 Rolling elements 51 Step surface 52 Female spline part 53 Rectangular hole 54a, 54b Support plate part 55a, 55b support hole 56 Locking hole 57, 57a Support shaft 58 Around 59 Through hole 60 Anti-slip member 61 Reducer 62 Warm 63 Side plate part 64 Cylindrical part 65 Pressure plate part 66 Outer Ring 67 Inner Circle 68 balls 69 Rolling surface 70 through hole 71 Female spline part 72 First rotating member 73 Male spline part 74 End Plate 75 Plate section 76 Convex 77 Outer diameter side unevenness 78 Nut 79 Locking groove 80, 80a biasing member 81, 81a fixed part 82 Step surface 83 Stopper surface 84 Slit 85 Narrow part 86 Wide section 87a, 87b Locking piece 88 Locking part 89 Output shaft 90 Connection protrusion 100 Clutch device 101 Input member 102 Output member 103 First member 103a Small diameter cylinder part 103b Side plate part 103c Large diameter cylinder 104 Second member 104a Circular part 104b Cylindrical part 105 Friction engagement part 105a 1st friction plate 105b 2nd friction plate 106 Cam device 106a Drive cam 106a1 Drive side cam surface 106a2 Gear section 106b Cam plate 106b1 Fixed side cam surface 106c Ball 107 Electric Actuator 107a Electric motor 107b Reducer 107b1 Output gear 108 Pressing member 109 Rolling bearings 110 Elastic member

Claims

1. A first member; a second member supported coaxially with the first member and capable of relative rotation with respect to the first member; a friction engagement portion having at least one first friction plate and one second friction plate supported so as to be capable of relative displacement in the axial direction; a cam device including: a drive cam having a cam surface on one axial side surface, rotatable relative to a fixed portion that does not rotate even when in use but supported so as not to be displaced in the axial direction; a holder supported so as to be displaceable in the axial direction but not to be rotated relative to the fixed portion; and a plurality of rolling elements held by the holder, each of which has a rolling surface that comes into rolling contact with the cam surface; an electric actuator that rotates the drive cam; a pressing member that faces the other axial side surface of the friction plate that is located furthest to the other axial side among the first friction plate and the second friction plate, and is supported so as to be movable toward and away from the friction plate located furthest to the other axial side in the axial direction; a rolling bearing disposed between the holder and the pressing member; an elastic member that elastically biases the pressing member toward the other axial direction; Equipped with By driving the drive cam to rotate with the electric actuator, the holder is displaced in a direction that widens the gap between the holder and the drive cam, and the first friction plate and the second friction plate are pressed against each other, thereby switching to a connection mode in which the first member and the second member rotate together; and by displacing the holder in a direction that narrows the gap between the holder and the drive cam, the force pressing the first friction plate and the second friction plate against each other is released, thereby switching to a disconnection mode in which the first member and the second member rotate relative to each other. Electric friction clutch device.

2. The rolling element has a cylindrical shape, The cam device includes a plurality of support shafts, each of which has both axial end portions supported by the holder, and a plurality of rollers, each of which is rollably disposed between the inner peripheral surface of the rolling element and the outer peripheral surface of the support shaft.

2. The electric friction clutch device according to claim 1.

3. the cam device includes a retaining member that prevents the support shaft from being displaced in the axial direction of the support shaft relative to the holder.

3. The electric friction clutch device according to claim 2.

4. the first member has a first cylindrical portion, the first friction plate is supported on an outer peripheral surface of the first cylindrical portion, the elastic member, a portion of the pressing member, and the rolling bearing are disposed radially inside the first cylindrical portion.

2. The electric friction clutch device according to claim 1.

5. the first member comprises a flange member having a first cylindrical portion and a circular ring portion bent radially inward from one axial end of the first cylindrical portion, and a shaft main body joined and fixed to an inner circumferential surface of the circular ring portion, The first friction plate is supported on the outer peripheral surface of the first cylindrical portion.

2. The electric friction clutch device according to claim 1.

6. the flange member is a pressed product, The shaft body is a forged product.

6. The electric friction clutch device according to claim 5.

7. the first member includes a retaining ring engaged with an outer peripheral surface of the first cylindrical portion, the first friction plate is supported on the outer peripheral surface of the first cylindrical portion so as to be displaceable in the axial direction, and is prevented from being displaced to one side in the axial direction by the retaining ring; 6. The electric friction clutch device according to claim 5.

8. The elastic member is constituted by a disc spring.

2. The electric friction clutch device according to claim 1.

9. The drive cam and / or the holder are made of sintered metal.

2. The electric friction clutch device according to claim 1.

10. the cam device includes a biasing member that elastically biases the drive cam in a direction in which the distance between the drive cam and the holder decreases.

2. The electric friction clutch device according to claim 1.

11. the actuator includes a biasing member that elastically biases the drive cam in a direction that reduces the gap between the drive cam and the holder.

2. The electric friction clutch device according to claim 1.

Images