JP2006057688A - Reverse input shutoff device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To release a conical clutch stably in a reverse input shutoff device capable of transmitting power from an input shaft to an output shaft by releasing engagement of the conical clutch and shutting off reverse input from the output shaft to the input shaft by engagement. <P>SOLUTION: A friction disc 5 is fitted into the output shaft 2 provided on the same axis as the input shaft 1 to rotationally lock it and is movably supported in the axial direction to energize the friction disc 5 toward the input shaft 1 by an elastic member 7. A conical movable friction face 12 is provided at the outer periphery of the friction disc 5, and a conical fixed friction face 11 forming a conical clutch 13 with the movable friction face 12 is formed at the inner periphery of a ring-like member 8 integrated with a housing 3. A torque cam means 20 is provided between a flange 1a of the input shaft 1 and the friction disc 5. A rotation resistance imparting means 30 is provided between the friction disc 5 and a side plate 3b of the housing 3 to give rotation resistance to the friction disc 5 by the rotation resistance imparting means 30. When inputting power into the input shaft 1, the input shaft 1 and the friction disc 5 thus rotate smoothly relatively to stabilize releasing of the conical clutch 13. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a reverse input blocking device that transmits power input to an input shaft to an output shaft and blocks reverse input from the output shaft to the input shaft.

  A device described in Patent Document 1 has been conventionally known as this type of reverse input blocking device. The reverse input blocking device described in Patent Document 1 is provided with an output side member coaxially with an input side member, and is an intermediate member that is prevented from rotating with respect to the output side member and is movably supported in the axial direction. A conical friction surface that forms a conical clutch is formed on each of the outer periphery of the stationary member and the inner periphery of a stationary member provided on the outer periphery thereof, and the spring force of the spring is applied to the intermediate member so that the conical clutch is fastened. Propulsion cam means for urging the intermediate member and displacing the intermediate member in the axial direction against the elasticity of the spring by the relative rotation of both members is provided between the input side member and the intermediate member. .

  In the reverse input shut-off device configured as described above, when power is input to the input side member, the propulsion cam means moves the intermediate member in the axial direction against the elasticity of the spring to release the engagement of the conical clutch. The rotation of the input side member is transmitted to the output side member via the intermediate member by releasing the fastening.

When the input to the input side member is stopped, the intermediate member is displaced in the direction of the input side member by the elasticity of the spring, and the cone is formed by the frictional engagement of the friction surface on the outer periphery of the intermediate member and the friction surface on the inner periphery of the stationary member. The clutch is engaged, and the power input to the output side member is cut off by the conical clutch to prevent transmission to the input side member.
JP 2000-346099 A

  By the way, in the above-described reverse input blocking device, the propulsion cam means provided between the input side member and the intermediate member is composed of a substantially V-shaped convex cam and a substantially V-shaped concave cam. When the power input to the motor is relatively small, the axial force acting on the intermediate member by the propulsion cam means becomes small. As a result, the conical clutch cannot be released stably, and the conical clutch is engaged and released. There was a problem of showing an unstable behavior of repeating.

  In addition, the operating characteristics and capacity of the conical clutch depend on the friction characteristics of the friction surfaces formed on the intermediate member and the stationary member, respectively. As a result, there is a problem of reducing the frictional fastening characteristics.

  A first object of the present invention is to provide a reverse input shut-off device that can stably release a conical clutch.

  A second object of the present invention is to provide a reverse input shut-off device capable of preventing the frictional face of the conical clutch from being struck or unevenly worn and obtaining a stable frictional fastening characteristic.

  In order to solve the first problem, in the first aspect of the invention, the input shaft, the output shaft arranged coaxially with the input shaft, the anti-rotation with respect to the output shaft, and the axial direction A friction disc formed on the outer periphery of a conical movable friction surface supported so as to be movable and capable of contacting a conical fixed friction surface provided on a stationary member, and the movable friction surface of the friction disc is fixed friction An elastic member that biases the friction disk in a direction that frictionally engages the surface; and an input member that is provided between the input shaft and the friction disk, and that moves away from the fixed friction surface by the relative rotation of the input shaft with respect to the friction disk. It comprises torque cam means for applying axial force and transmitting rotational torque between the input shaft and the friction disk in a disengaged state of the movable friction surface with respect to the fixed friction surface. A reverse input blocking device for blocking reverse input from an output shaft to an input shaft by frictional engagement of a friction surface, and a rotation resistance applying means for applying a rotation resistance to the friction disk between the friction disk and a stationary member The structure which provided is adopted.

  Here, the rotational resistance applying means is composed of an annular friction plate facing the friction disk in the axial direction and an elastic member incorporated between the friction plate and the friction disk or between the stationary member and the friction plate. Can be adopted.

  In order to solve the second problem, in the second invention, in the reverse input shutoff device according to the first invention, one of the fixed friction surface and the movable friction surface is convex in a cross-sectional shape. A conical surface having a curved line is adopted.

  Here, if the fixed friction surface is formed on the inner periphery of the ring-shaped member integrated with the stationary member, it is easy to process the fixed friction surface, and a highly accurate fixed friction surface with less processing error is obtained. And the frictional engagement characteristics of the conical clutch can be further improved.

  As in the first aspect of the invention, the rotational resistance applying means is provided between the friction disk and the stationary member, and the rotational resistance is applied to the friction disk by the rotational resistance applying means, so that the power input to the input shaft is small. Even in the region, the friction disk causes a phase delay relative to the input shaft, and the torque cam means can be operated reliably. Since the axial force is generated by the operation of the torque cam means, and the friction disk moves to the output shaft side by the axial force, the conical clutch can be released stably.

  Further, as in the second aspect of the invention, one of the fixed friction surface and the movable friction surface is a conical surface having a convex circular curve in cross section, so In addition, uneven wear due to this can be prevented, and the frictional engagement characteristics of the conical clutch can be stabilized.

  Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the input shaft 1 and the output shaft 2 are arranged on the same axis, the shaft end faces are opposed, and the opposed ends are covered with a housing 3 as a stationary member.

  The housing 3 is fixedly arranged, and bearings 4 that rotatably support the input shaft 1 and the output shaft 2 are provided on the opposing side plates 3a and 3b, respectively.

  The input shaft 1 has a flange 1a at the shaft end located in the housing 3, and the friction disk 5 faces the flange 1a in the axial direction.

  The friction disk 5 is fitted to the shaft end portion of the output shaft 2, and the friction disk 5 is prevented from rotating with respect to the output shaft 2 by a spline 6 provided between the fitting surfaces, and is movable in the axial direction. ing.

  An elastic member 7 made of a disc spring is incorporated between the opposing surfaces of the flange 2 a formed at the shaft end of the friction disk 5 and the output shaft 2. The elastic member 7 urges the friction disk 5 toward the flange 1 a of the input shaft 1.

  A ring-shaped member 8 is provided outside the friction disk 5. The ring-shaped member 8 is fitted on the inner diameter surface of the housing 3. A plurality of holes 9 are formed in one side surface of the ring-shaped member 8 facing the one side plate 3 a of the housing 3, while one side plate 3 a of the housing 3 is added to the hole 9. A fastening projection 10 is provided, and the ring-shaped member 8 is integrated with the housing 3 by fitting the crimping projection 10 with the hole 9.

  A conical fixed friction surface 11 is provided on the inner periphery of the ring-shaped member 8, while a conical movable friction surface 12 is formed on the outer periphery of the friction disk 5. The conical clutch 13 is formed.

  Torque cam means 20 is provided between the friction disk 5 and the flange 1 a of the input shaft 1.

  As shown in FIGS. 1 to 3, the torque cam means 20 has a plurality of cam grooves 21, 22 that gradually decrease in the groove depth from the center in the circumferential direction to both ends in the circumferential direction on the opposing surfaces of the flange 1 a and the friction disk 5. Are formed at intervals in the circumferential direction, and a ball 23 is incorporated between the cam grooves 21 and 22. The torque cam means 20 applies an axial force to the friction disk 5 by relative rotation of the input shaft 1 and the friction disk 5, and moves the friction disk 5 in the axial direction in a direction in which the movable friction surface 12 is separated from the fixed friction surface 11. It is like that.

  As shown in FIG. 1, a rotational resistance applying means 30 for applying rotational resistance to the friction disk 5 is provided between the friction disk 5 and the other side plate 3 b of the housing 3.

  The rotation resistance applying means 30 includes an annular friction plate 31 that can contact the inner surface of the other side plate 3 b of the housing 3, and an elastic member 32 incorporated between the friction plate 31 and the friction disk 5. The friction plate 31 is pressed against the inner surface of the other side plate 3 b of the housing 3 by the member 32, and the friction resistance acting on the pressure contact surface, or the contact surface between the friction plate 31 and the elastic member 32, and the elastic member 32 and the friction disk 5 The frictional resistance acting on the contact surface is the rotational resistance of the friction disk 5.

  The reverse input blocking device shown in the embodiment has the above-described structure, and when the input shaft 1 is stopped, the friction disk 5 is incorporated between the output shaft 2 and the elastic member 7 of the rotational resistance applying means 30. The movable friction surface 12 on the outer periphery of the friction disk 5 is pressed against the fixed friction surface 11 of the ring-shaped member 8 by being pressed by 32, and the conical clutch 13 is held in the engaged state.

  When power is input to the input shaft 1 and the input shaft 1 rotates when the conical clutch 13 is engaged as described above, the input shaft 1 and the friction disk 5 rotate relative to each other, and the relative rotation causes the flange 1a to be provided. As shown in FIG. 5, the cam groove 21 formed in the friction disk 5 and the cam groove 22 are out of phase in the circumferential direction, and an axial force is generated in the torque cam means 20. At this time, the friction disk 5 Since the rotation resistance is loaded by the applying means 30, a stable axial force is generated regardless of the magnitude of the power input to the input shaft 1. Since this axial force is applied to the friction disk 5, the friction disk 5 moves away from the flange 1a of the input shaft 1 against the elasticity of the elastic members 7 and 32, and as shown in FIG. The movable friction surface 12 of the disk 5 is separated from the fixed friction surface 11 of the ring-shaped member 8 so that the conical clutch 13 is released from the engaged state.

  Therefore, the power input to the input shaft 1 is transmitted to the friction disk 5 via the balls 23 of the torque cam means 20, and is transmitted from the friction disk 5 to the output shaft 2 so that the output shaft 2 is in the same direction as the input shaft 1. Rotate to.

  When the input shaft 1 is stopped in the power transmission state from the input shaft 1 to the output shaft 2, the friction disk 5 is moved by the pressing force of the elastic member 7 provided on the output shaft 2 and the elastic member 32 of the rotation resistance applying means 30. It moves toward the flange 1a of the input shaft 1.

  At this time, the ball 23 presses the inclined groove bottom surface of the cam groove 21 formed in the flange 1 a and the inclined groove bottom surface of the cam groove 22 provided in the friction disk 5 presses the ball 23. The friction disk 5 rotates while moving in the axial direction, and as a result, the ball 23 is held in a stable state where the groove depths of the cam grooves 21 and 22 are the deepest as shown in FIG. As shown in FIG. 1, the movable friction surface 12 is brought into pressure contact with the fixed friction surface 11 of the ring-shaped member 8, and the conical clutch 13 is engaged.

  For this reason, when power is input to the output shaft 2, the reverse input is received by the conical clutch 13, and transmission to the input shaft 1 is interrupted.

  As shown in the embodiment, the rotational resistance applying means 30 is provided between the friction disk 5 and the other side plate 3 b of the housing 3, and the rotational resistance is applied to the friction disk 5 by the rotational resistance applying means 30. Even when the power input to 1 is small, the input shaft 1 and the friction disk 5 can be relatively reliably rotated.

  As a result, the torque cam means 20 can be operated reliably, the friction disk 5 can be moved away from the ring-shaped member 8 by the axial force generated by the torque cam means 20, and the conical clutch 13 can be stably operated. It can be released.

  Further, by forming the fixed friction surface 11 on the inner periphery of the ring-shaped member 8 integrated with the housing 3, the processing of the fixed friction surface 11 is performed as compared with the case where the fixed friction surface 11 is directly formed on the housing 3. Thus, the fixed friction surface 11 with high accuracy can be obtained, and the conical clutch 13 having excellent frictional fastening characteristics can be obtained.

  6 (I) to (III) show other examples of the conical clutch 13. In the conical clutch 13 shown in FIG. 6 (I), the fixed friction surface 11 on the inner periphery of the ring-shaped member 8 is a conical surface having a straight cross section, and the movable friction surface 12 on the outer periphery of the friction disk 5 is used. The conical surface is a convex circular curve.

  In the conical clutch 13 shown in FIG. 6 (II), the fixed friction surface 11 on the inner periphery of the ring-shaped member 8 is a conical surface having a straight cross section, and the movable friction surface 12 on the outer periphery of the friction disk 5 is used. The cross-sectional shape is a conical surface provided with circular arcs at both ends of the straight line C.

  In addition, in the conical clutch 13 shown in FIG. 6 (III), the fixed friction surface 11 on the inner periphery of the ring-shaped member 8 is a conical surface having a convex circular shape in cross section, and the outer periphery of the friction disk 5 The movable friction surface 12 is a conical surface having a straight cross-sectional shape.

  As shown in FIGS. 6 (I) to (III), one of the fixed friction surface 11 and the movable friction surface 12 is a conical surface having a curve with a convex cross section. Further, uneven wear caused by it can be prevented, and stable frictional fastening characteristics can be obtained.

  In the embodiment, the torque cam means 20 includes the cam grooves 21 and 22 and the ball 23. However, the torque cam means 20 may include a mountain-shaped cam protrusion and a V groove.

Longitudinal front view showing an embodiment of a reverse input blocking device according to the present invention Sectional view along the line II-II in FIG. Transverse plan view of the torque cam means shown in FIG. Sectional view showing the state of power transmission from the input shaft to the output shaft Sectional view of the torque cam means in the power transmission state (I) thru | or (III) is sectional drawing which shows the other example of a conical clutch

Explanation of symbols

1 Input shaft 2 Output shaft 3 Housing (stationary member)
5 friction disk 7 elastic member 8 ring-shaped member 11 fixed friction surface 12 movable friction surface 20 torque cam means 30 rotation resistance applying means 31 friction plate 32 elastic member

Claims (4)

  An input shaft, an output shaft arranged coaxially with the input shaft, and a conical fixed friction surface provided on a stationary member that is supported by the shaft so as to be non-rotatable and movable in the axial direction. A friction disk having a conical movable friction surface that can be contacted with the outer periphery formed on the outer periphery, an elastic member that biases the friction disk in a direction in which the movable friction surface of the friction disk frictionally engages the fixed friction surface, Provided between the input shaft and the friction disk, the relative rotation of the input shaft with respect to the friction disk applies an axial force in a direction away from the fixed friction surface to the friction disk, and disengages the movable friction surface from the fixed friction surface. Torque cam means that transmits rotational torque between the input shaft and the friction disk in the state, and reverse input from the output shaft to the input shaft by frictional engagement of the movable friction surface and the fixed friction surface of the friction disk. In the reverse input blocking device which is adapted to the cross-sectional, reverse input blocking device, characterized in that a rotational resistance applying means for applying rotational resistance to the friction disk therebetween of said friction disc and the stationary member.   2. The reverse input blocking device according to claim 1, wherein one of the fixed friction surface and the movable friction surface is a conical surface having a convex circular curve in cross-sectional shape.   The reverse input blocking device according to claim 1, wherein the fixed friction surface is provided on an inner diameter of a ring-shaped member attached to a stationary member.   The rotation resistance applying means comprises an annular friction plate facing the friction disk in the axial direction, and an elastic member incorporated between the friction plate and the friction disk or between the stationary member and the friction plate. 4. The reverse input shut-off device according to any one of 3.

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