JP2018168887A - Reverse input prevention clutch - Google Patents

Abstract

To provide a lock type reverse input prevention clutch which reduces a torque loss in transmitting rotation from an input-side member to an output-side member.SOLUTION: When transmitting rotation from an input side to an output side, a first unlock piece 11 pushed by a pillar part 2c of a rotation transmission ring 2 that is rotated integrally with an input shaft 1 is rotated in the same direction as input torque, and a pillar part 11c of the first unlock piece extrudes a roller (lock engage element) 14 at a rear side in a rotation direction to a wide part of a wedge-shaped space 16. A pin 18 which is fixed to the rotation transmission ring 2 turns a rotation direction conversion arm 13 around a support shaft 17 that is fixed to an output-side inner ring 5, and a second unlock piece 12 which is pushed by the rotation direction conversion arm 13 is rotated reversely to the input torque. A pillar part 12c of the second unlock piece extrudes a roller 14 at a front side in the rotation direction to the wide part of the wedge-shaped space 16. Thus, each of the rollers 14 is not brought into contact with a cylindrical surface of an inner periphery of an outer ring 7, and a torque loss is prevented from occurring because of friction between the roller 14 and the outer ring 7.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a reverse input prevention clutch that transmits rotation of an input side member to an output side member when input torque is applied, and prevents the input side member from rotating with respect to reverse input torque.

  The reverse input prevention clutch transmits its rotation to the output side member when input torque is applied to the input side member, and prevents the input side member from rotating when reverse input torque is applied to the output side member. It is to make. There is a type of the reverse input prevention clutch that locks the output side member against reverse input torque (hereinafter, this method is referred to as “lock type”).

  For example, in Patent Document 1, torque transmission that transmits rotation (input torque) of an input side member to an output side member with a slight angular delay between an input side member and an output side member that rotate about the same axis. A fixing member is arranged on the radially outer side of the output side member, a plurality of cam surfaces are provided on the outer peripheral surface of the output side member, and the inner peripheral cylindrical surface of the fixing member and each cam surface of the output side member A wedge-shaped space gradually narrowing on both sides in the circumferential direction is formed, and a pair of rollers (lock engagement elements) and springs (elastic members) that push the rollers into the narrow portion of the wedge-shaped space are incorporated in each wedge-shaped space, A lock-type reverse input prevention clutch has been proposed in which a column portion of an unlocking piece that rotates integrally with an input side member is inserted on each wedge-shaped space on both sides in the circumferential direction (positions facing the spring in the circumferential direction with a roller in between). Yes.

  In this reverse input prevention clutch, each roller is pushed into the narrow part of the wedge-shaped space by the elasticity of the spring. Therefore, even if reverse input torque is applied to the output side member, the roller on the rear side in the rotational direction is fixed to the fixed member and the output. By engaging with the side member, the output side member is locked with the fixed member, and rotation is not transmitted to the input side member.

  On the other hand, when an input torque is applied to the input side member, the column portion of the unlocking piece that rotates together with the input side member pushes the roller on the rear side in the rotation direction against the elastic portion of the spring to the wide portion of the wedge-shaped space. Thus, after the engagement between the roller and the fixing member and the output side member is released and the output side member is released from the locked state, the rotation is transmitted from the input side member to the output side member by the torque transmitting means. (At this time, since the roller on the front side in the rotational direction moves relative to the wide portion of the wedge-shaped space, it does not engage with the fixed member and the output side member).

JP 2010-281375 A

  By the way, in the lock type reverse input prevention clutch as described above, when the rotation is transmitted from the input side member to the output side member, the roller slides with the inner peripheral cylindrical surface of the fixing member, so that the roller is fixed. Torcross is generated due to friction with the member. At this time, since the roller on the rear side in the rotation direction rotates while being pushed out to the wide part of the wedge-shaped space, the torcross to be generated is difficult to increase. Since it rotates in the pressed state, a torque cross larger than the roller on the rear side in the rotation direction is generated. The torcross generated by the roller in the front in the rotational direction is often a size that cannot be ignored with respect to the rotational torque of only the output side member. This is an energy saving and driving mechanism for the device incorporating the reverse input prevention clutch. This is one of the factors that hinder miniaturization of motors.

  Then, this invention makes it a subject to provide the lock type reverse input prevention clutch with a small torque cross when transmitting rotation from an input side member to an output side member.

  In order to solve the above problems, a reverse input preventing clutch according to the present invention includes an input side member and an output side member arranged in a state of rotating around the same axis, and a radially outer side of the output side member. A locking member that locks the output side member and the fixing member with respect to the reverse input torque applied to the output side member, and the locking means with respect to the input torque applied to the input side member. Unlocking means for releasing the locked state, and torque transmitting means for transmitting the input torque applied to the input side member to the output side member when the locked state is released, wherein the locking means includes: A cylindrical surface is provided on the inner periphery of the fixed member, and a plurality of cam surfaces are provided on the outer periphery of the output side member, between the inner peripheral cylindrical surface of the fixed member and each cam surface of the output side member. Circumference Wedge-shaped spaces that are gradually narrowed on both sides are formed, a pair of lock engagement elements in each of these wedge-shaped spaces, and an elastic member that is sandwiched between the pair of lock engagement elements and pushes each lock engagement element into the narrow portion of the wedge-shaped space And the unlocking means includes a pair of lock engaging members incorporated in each wedge-shaped space when an input torque is applied to the input side member, both of which are the elastic members. It was set as the structure which extrudes to the vast part of the said wedge-shaped space against the elasticity of.

  According to the above configuration, when the input torque is applied to the input side member, the lock release means pushes out the pair of lock engagement elements to the wide part of the wedge-shaped space, so that only the lock engagement element on the rear side in the rotation direction is When the rotation is transmitted from the input side member to the output side member, the lock engagement element on the front side in the rotational direction comes into contact with the inner peripheral cylindrical surface of the fixing member. It becomes difficult to reduce the amount of the lock engagement element on the front side in the rotational direction in the torque cross due to the friction between each lock engagement element and the fixing member.

  Here, as the unlocking means, a first unlocking piece having a column part rotatably arranged around the axis of the input side member and inserted on one side in the circumferential direction of each wedge-shaped space. And a second unlocking piece having a column portion that is rotatably arranged around the axis of the input side member and is inserted on the other circumferential side of each wedge-shaped space, and the input side member When the input torque is applied, the first lock release piece and the second lock release piece rotate in opposite directions, and the lock engaging members whose respective pillar portions are opposed to each other in the circumferential direction are moved to the wedge shape. What pushes out to the vast part of space can be adopted.

  When the above-described unlocking means is employed, the means for rotating the first unlocking piece and the second unlocking piece in opposite directions is a support that extends in parallel with the axis of the output side member. A shaft is provided, and a longitudinally central portion of the rotational direction conversion arm is rotatably supported by the support shaft, and when the input torque is applied to the input side member, the first unlocking is performed. One unlocking piece of the piece and the second unlocking piece is pushed by the input side member and rotates in the same direction as the input torque, and the rotational direction conversion arm has one end thereof as the input side member. By pressing and rotating, it is preferable to push the other unlocking piece at the other end and rotate it in the direction opposite to the input torque.

  Further, as the first unlocking piece and the second unlocking piece, when the opposing surfaces of the respective column portions to the lock engaging element push out the lock engaging element to the wide part of the wedge-shaped space, By adopting an inclined surface that restricts the movement of the lock engagement element toward the inner peripheral cylindrical surface side of the fixing member, the contact of the lock engagement element with the fixing member is more reliably prevented, and the input side member It is possible to reduce the torque cross when the rotation is transmitted to the output side member.

  As described above, the reverse input preventing clutch of the present invention is configured such that when the input release member is applied with input torque and the unlocking means releases the locked state between the output side member and the fixing member, the unlocking means is a pair of the unlocking means. Both lock engagement elements are pushed out to the wide part of the wedge-shaped space between the fixed member and the output side member. Therefore, when the rotation is transmitted from the input side member to the output side member, The engaging element is also difficult to contact the fixing member, and the torque cross is small. Therefore, in the device incorporating this reverse input preventing clutch, energy saving and downsizing of the drive motor can be achieved as compared with the conventional device.

Vertical front view of reverse input prevention clutch of embodiment 1 is an exploded perspective view of FIG. Sectional view along line III-III in FIG. Sectional drawing explaining clutch operation when input torque is applied corresponding to FIG. Sectional drawing explaining the clutch operation | movement following FIG. 4 corresponding to FIG. Sectional drawing explaining the clutch operation | movement following FIG. 5 corresponding to FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 3, the reverse input prevention clutch includes an input side member 3 including an input shaft 1 and a rotation transmission ring 2, an output side member 6 in which an inner ring 5 is integrally formed on the output shaft 4, and A fixing member 10 including a housing 8 and a presser lid 9 integrally formed with the outer ring 7, first and second unlocking pieces 11 and 12 rotatably fitted on the outer periphery of the input shaft 1, and one of the inner rings 5 The rotation direction conversion arm 13 attached to the end face, the roller (lock engagement element) 14 and the coil spring (elastic member) 15 incorporated between the inner ring 5 and the outer ring 7 are basically configured. In addition, the roller 14 can be replaced with a lock engaging member made of another rolling element such as a ball, and the coil spring 15 can be replaced with another elastic member such as a leaf spring.

  The fixing member 10 is formed by integrally forming an outer ring 7 disposed on the radially outer side of the inner ring 5 with a two-stage cylindrical housing 8 and attaching a presser lid 9 to one end of the housing 8. The housing 8 has a plurality of notches 8a formed on the outer peripheral edge of the flange at one end, and the claws 9a formed on the outer peripheral edge of the presser lid 9 are fitted into these notches 8a and bent in the circumferential direction. Thus, it is integrated with the presser lid 9. Each of the three tongue-shaped projecting portions projecting from the outer periphery of the presser lid 9 is provided with attachment holes 9b. By these attachment holes 9b, the presser lid 9 is attached to an external member (not shown) on the housing 8. And are fixed together. The small-diameter cylindrical portion at the other end of the housing 8 serves as a bearing that rotatably supports the output shaft 4.

  The input side member 3 has a rotation transmission ring 2 fitted on the outer periphery of the input shaft 1. The input shaft 1 includes an engaging portion 1a having a two-sided width (two engaging surfaces parallel to the shaft center and parallel to each other) on the outer periphery, and a small-diameter cylindrical portion 1b protruding from the end surface of the engaging portion 1a. And have. The cylindrical portion 2a of the rotation transmission ring 2 is fitted into the axially central portion of the engagement portion 1a of the input shaft 1 so that the input shaft 1 and the rotation transmission ring 2 rotate integrally. And the front end side part of the engaging part 1a of the input shaft 1 is inserted into the engaging hole 5a provided in the center of the inner ring 5, and the small diameter cylindrical part 1b extends from the bottom of the engaging hole 5a of the inner ring 5 to the output shaft 4. The input side member 3 (input shaft 1 and rotation transmission ring 2) and the output side member 6 (output shaft 4 and inner ring 5) rotate around the same axis. Yes.

  Further, the engagement hole 5a of the inner ring 5 is formed so that a slight clearance in the rotational direction is generated when the engagement portion 1a of the input shaft 1 is inserted, whereby input torque applied to the input shaft 1 is formed. Is transmitted to the output side member 6 with a slight angular delay.

  An input torque is applied to the input shaft 1 from a drive source (not shown) such as a motor, and the output shaft 4 is a rotation transmission member (such as an output gear) attached to an engaging portion 4b having a two-sided width formed on the outer periphery. Torque is output in the illustration (not shown).

  The inner periphery of the outer ring 7 of the fixing member 10 is a cylindrical surface, and a plurality of cam surfaces 5 b are provided in the circumferential direction on the outer periphery of the inner ring 5, and the inner peripheral cylindrical surface of the outer ring 7 and each cam surface 5 b of the inner ring 5. A wedge-shaped space 16 is formed which gradually narrows on both sides in the circumferential direction. A pair of the rollers 14 is incorporated in each wedge-shaped space 16, and the coil spring 15 is assembled so as to be sandwiched between the pair of rollers 14, and each roller 14 is pushed into a narrow portion of the wedge-shaped space 16. Yes. As a result, a locking unit is configured to lock the inner ring 5 that is a part of the output side member 6 and the outer ring 7 that is a part of the fixing member 10 against reverse input torque applied to the output side member 6. .

  Each of the first and second unlocking pieces 11, 12 includes annular portions 11 a, 12 a that are rotatably fitted on the outer periphery of the input shaft 1, and an arm portion that extends radially outward from the annular portions 11 a, 12 a. Column portions 11c and 12c to be inserted into the radial gaps of the inner ring 5 and the outer ring 7 are formed at the tips of 11b and 12b. The column part 11c of the first unlocking piece 11 is inserted into one side in the circumferential direction of each wedge-shaped space 16 (a position facing the one end of the coil spring 15 in the circumferential direction with the roller 14 in between). The column portion 12c of the release piece 12 is inserted on the other circumferential side of each wedge-shaped space 16 (a position facing the other end of the coil spring 15 in the circumferential direction with the roller 14 interposed therebetween). The opposite surfaces of the column portions 11 c and 12 c of the lock release pieces 11 and 12 that are opposed to the rollers 14 are inclined surfaces that project radially outward toward the wide portion of the wedge-shaped space 16.

  And the pillar extended in the axial direction from the outer peripheral part of the annular part 2b of the said rotation transmission ring 2 between the opposing surfaces to the roller 14 of the pillar parts 11c and 12c of both lock release pieces 11 and 12 on the opposite side. Part 2c is inserted. Further, on the inner side in the radial direction of the column part 2 c of the rotation transmission ring 2, a support shaft 17 that extends in parallel with the shaft center from one end face of the inner ring 5 between the arm parts 11 b and 12 b of both lock release pieces 11 and 12. Is inserted, and the central portion in the longitudinal direction of the rotational direction conversion arm 13 is rotatably supported on each of the support shafts 17. At one end in the longitudinal direction of each rotation direction conversion arm 13, a notch 13a having a semicircular shape on the back side is formed, and a pin protruding from the annular portion 2b of the rotation transmission ring 2 to the output side in this notch 13a. 18 is slidably fitted.

  This reverse input prevention clutch has the above-described configuration, and each roller 14 is pushed into the narrow portion of the wedge-shaped space 16 by the elasticity of the coil spring 15, so that even if reverse input torque is applied to the output side member 6, The output side member 6 is locked to the fixing member 10 by engaging the roller 14 on the rear side in the rotation direction with the outer ring 7 which is a part of the fixing member 10 and the inner ring 5 which is a part of the output side member 6. The rotation is not transmitted to the member 3.

  On the other hand, when an input torque is applied to the input shaft 1 of the input side member 3, the rotation is transmitted to the output side member 6. This rotation transmission operation is shown in FIGS. A description will be given based on the case of counterclockwise rotation as viewed from the input side.

  When input torque is applied to the input shaft 1, first, as shown in FIG. 4, the rotation transmission ring 2 rotates integrally with the input shaft 1, and the column portion 2 c of the rotation transmission ring 2 becomes the first unlocking piece. 11, the plurality of pins 18 fixed to the rotation transmission ring 2 press one end of the rotation direction conversion arm 13, and the rotation direction conversion arm 13 is fixed to the inner ring 5. By rotating around the shaft 17, the other end of each rotation direction conversion arm 13 comes into contact with the arm portion 12 b of the second unlocking piece 12.

  After that, as shown in FIG. 5, the first unlocking piece 11 pushed by the column portion 2c of the rotation transmission ring 2 rotates in the same direction as the input torque, and the column portion 11c is a roller 14 on the rear side in the rotation direction. Is pushed out against the elasticity of the coil spring 15 to the wide portion of the wedge-shaped space 16, and the second unlocking piece 12 pushed by the rotation direction converting arm 13 rotates in the direction opposite to the input torque, and its column portion 12c. By pushing the roller 14 on the front side in the rotational direction against the elasticity of the coil spring 15 to the wide part of the wedge-shaped space 16, the engagement between each roller 14 and the outer ring 7 and the inner ring 5 is released, and the output side member 6 Is released from the locked state. That is, the lock for releasing the locked state of the output side member 6 by the mechanism that rotates the first unlocking piece 11 and the second unlocking piece 12 in the opposite directions by the rotation transmission ring 2 and the rotation direction conversion arm 13. Release means is configured.

  Then, when the input shaft 1 further rotates from the state of FIG. 5, the engaging portion 1a of the input shaft 1 and the engaging hole 5a of the inner ring 5 are engaged as shown in FIG. The rotation is transmitted to the output shaft 4 via the inner ring 5.

  Contrary to the examples described with reference to FIGS. 4 to 6, when a clockwise input torque is applied to the input shaft 1 as viewed from the input side, the column portion 2c of the rotation transmission ring 2 is second unlocked. Although the piece 12 is pushed and the rotation direction changing arm 13 pushes the first unlocking piece 11, the operation other than the above is performed, and the rotation is transmitted to the output side member 6.

  In this reverse input prevention clutch, as described above, when the rotation is transmitted from the input side member 3 to the output side member 6, each roller 14 is pushed out to the wide part of the wedge-shaped space 16, and each lock Since the opposing surfaces of the release portions 11 and 12 of the column portions 11c and 12c to the rollers 14 are inclined surfaces that restrict the movement of the rollers 14 toward the inner peripheral cylindrical surface of the outer ring 7, each roller 14 is an outer ring. 7 does not come into contact with the inner peripheral cylindrical surface, and the torcross due to friction between the roller 14 and the outer ring 7 does not occur. Therefore, in the device incorporating this reverse input preventing clutch, energy saving and downsizing of the drive motor can be achieved as compared with the conventional device. Further, since heat generation due to friction between the roller 14 and the outer ring 7 does not occur, the present invention can be applied to applications that rotate at high speed.

  In addition, it is desirable that the surface of each unlocking piece that faces the roller of the column portion is an inclined surface as in the above-described embodiment in order to reliably prevent the roller from coming into contact with the outer ring. It is good also as a plane substantially orthogonal to the direction which presses a roller. Even in this case, when the rotation is transmitted from the input side to the output side as compared with the conventional reverse input prevention clutch that pushes only the roller on the rear side in the rotation direction to the wide part of the wedge-shaped space, the front side in the rotation direction Since the roller is less likely to come into contact with the inner peripheral cylindrical surface of the outer ring, it is possible to reduce the amount of the roller on the front side in the rotational direction in the torque cross due to friction between each roller and the outer ring.

DESCRIPTION OF SYMBOLS 1 Input shaft 1a Engagement part 2 Rotation transmission ring 2c Column 3 Input side member 4 Output shaft 5 Inner ring 5a Engagement hole 5b Cam surface 6 Output side member 7 Outer ring 8 Housing 9 Presser lid 10 Fixing member 11 First unlocking Piece 11c Column 12 Second unlocking piece 12c Column 13 Rotation direction conversion arm 14 Roller (lock engagement element)
15 Coil spring (elastic member)
16 Wedge-shaped space 17 Spindle 18 Pin

Claims (4)

An input side member and an output side member arranged in a state of rotating around the same axis, a fixed member arranged on a radially outer side of the output side member, and a reverse input torque applied to the output side member The lock means for locking the output side member and the fixing member with respect to the above, the lock release means for releasing the lock state by the lock means for the input torque applied to the input side member, and the lock state released Torque transmitting means for transmitting an input torque applied to the input side member to the output side member when in a state;
The locking means is provided with a cylindrical surface on the inner periphery of the fixed member, and a plurality of cam surfaces are provided on the outer periphery of the output side member, and the inner peripheral cylindrical surface of the fixed member and each cam surface of the output side member Wedge-shaped spaces that are gradually narrowed on both sides in the circumferential direction, and a pair of lock engagement elements in each of these wedge-shaped spaces, and each lock engagement element sandwiched between the pair of lock engagement elements to narrow the wedge-shaped space And an elastic member that is pushed into the part,
When the input side member is applied with an input torque, the unlocking means applies a pair of lock engaging elements incorporated in each wedge-shaped space to both the wedge-shaped space against the elastic force of the elastic member. Reverse input prevention clutch that pushes out to the vast part of   The unlocking means is arranged so as to be rotatable around the axis of the input side member, and includes a first unlocking piece having a column part inserted on one side in the circumferential direction of each wedge-shaped space, and the input And a second unlocking piece having a column part that is rotatably arranged around the axis of the side member and inserted on the other circumferential side of each wedge-shaped space, and the input side member receives input torque. When added, the first unlocking piece and the second unlocking piece rotate in opposite directions to each other, and the lock engaging elements whose respective pillar parts oppose each other in the circumferential direction are moved to the wide part of the wedge-shaped space. 2. The reverse input preventing clutch according to claim 1, wherein the reverse input preventing clutch is pushed out to the rear.   The means for rotating the first unlocking piece and the second unlocking piece in directions opposite to each other is provided with a support shaft extending in parallel to the shaft center of the output side member, and is rotated about the support shaft. A central portion in the longitudinal direction of the direction conversion arm is rotatably supported, and one of the first unlocking piece and the second unlocking piece is applied when an input torque is applied to the input side member. The unlocking piece is rotated by the input side member in the same direction as the input torque, and the rotation direction conversion arm is rotated by being pushed by the input side member at one end thereof. 3. The reverse input prevention clutch according to claim 2, wherein the other end of the lock release piece is pushed at the end portion to rotate in the direction opposite to the input torque.   The first unlocking piece and the second unlocking piece are arranged such that the surfaces of the respective pillar portions facing the lock engaging member push the lock engaging member to the wide part of the wedge-shaped space. 4. The reverse input preventing clutch according to claim 2, wherein the clutch is an inclined surface that restricts movement of the lock engagement element toward the inner peripheral cylindrical surface.

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