JP2010106950A - Reverse input preventing clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reverse input preventing clutch that prevents a catching phenomenon when reverse input torque is applied to an output side member. <P>SOLUTION: Rollers 10 arranged between an input outer ring 2 and an output inner ring 5 are protruded from one end of the cylindrical face of the inner ring 5, a cylindrical part 8a of a presser cover 8 as part of a fixing member 9 is extended to a position opposite to protruded parts of the rollers 10 in the radial direction, and an O-ring 13 is fitted into an annular groove 8b in the outer peripheral face thereof. When input torque is applied to the rollers 10 to engage with the outer ring 2 and the inner ring 5, the O-ring 13 is pushed by the rollers 10 and elastically deformed. When the input torque is no longer applied, the O-ring 13 thrusts the rollers 10 to the side of the outer ring 2 with elastic restoring force. Thus, when reverse input torque is applied, the rollers 10 are constrained not to be moved to the narrow side of a wedge space and does not engage with the outer ring 2 and the inner ring 5, and so the inner ring 5 and an output shaft 4 smoothly idle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a reverse input prevention clutch that transmits rotation of an input side member to an output side member and prevents rotation of the output side member from being transmitted to the input side member.

The reverse input prevention clutch that transmits the rotation of the input side member to the output side member and prevents the rotation of the output side member from being transmitted to the input side member is output when reverse input torque is applied to the output side member. There is a system in which the side member is idled (see, for example, Patent Document 1).
Japanese Patent No. 3914778

  The reverse input prevention clutch described in Patent Document 1 is arranged so that the input side member and the output side member rotate around the same axis, and forms a cylindrical surface on the outer peripheral side of the output side member. A plurality of cam surfaces are provided on the side member in the circumferential direction so as to face the cylindrical surface of the output side member in the circumferential direction, and a wedge-shaped space gradually narrowing in the circumferential direction is formed between the cylindrical surface and each cam surface. A roller is arranged in each wedge-shaped space, and each roller is accommodated one by one in a pocket of a cage arranged between both members, and is held so as to be disengageable from both members. The cage is centered on the input side member. A sliding spring that is connected via a spring and slides with the cylindrical portion of the fixing member in a state of being engaged with the cage is incorporated.

  When an input torque is applied to the input side member, the centering spring is elastically deformed between the input side member and the cage that receives the sliding resistance of the sliding spring, and the rotational position of the input side member and the cage is Due to the phase difference, the rollers held by the cage move relatively to the narrow side of the wedge-shaped space and engage with the input side member and the output side member, and the rotation of the input side member is transmitted to the output side member. On the other hand, when reverse input torque is applied to the output side member, the rollers are held in a state of being separated from the input side member and the output side member by the cage, so that the rotation of the output side member is not transmitted to the input side member. It has become.

  By the way, in the reverse input prevention clutch described above, when torque input is interrupted during rotation transmission from the input side to the output side, the rollers are in contact with the cam surface of the input side member and the cylindrical surface of the output side member ( Stop in lock standby mode. For this reason, when reverse input torque is applied in the same direction as the input torque before stopping, the rollers move to the wide side of the wedge-shaped space due to frictional force with the output side member, and the output side member idles. When reverse input torque in the direction is applied, the rollers intermittently engage with the input side member and the output side member at the start of rotation of the output side member. There may be a phenomenon that rotation is slightly transmitted (hereinafter referred to as “hook”).

  An object of the present invention is to prevent a catching phenomenon when reverse input torque is applied to an output side member in a reverse input prevention clutch.

  In order to solve the above-described problems, the present invention provides an input side member and an output side member so as to rotate around the same axis, and forms a cylindrical surface on the outer peripheral side or inner peripheral side of the output side member. A plurality of cam surfaces radially facing the cylindrical surface of the output side member on the input side member, and a wedge-shaped space gradually narrowing in the circumferential direction between the cylindrical surface and each cam surface. When the input torque is applied to the input side member by forming rollers in each wedge-shaped space, locking means provided between the rollers and the fixing member attach the rollers to the wedge-shaped space. Relative movement to the narrow side and engagement with the input side member and output side member causes the rotation of the input side member to be transmitted to the output side member, and when reverse input torque is applied to the output side member, The side member idles and the rotation of the output side member is transmitted to the input side member. In the reverse input prevention clutch, the lock release assisting means for restraining the rollers so that the rollers do not move to the narrow side of the wedge-shaped space when the output side member is rotated by the reverse input torque is provided. .

  That is, when the output side member is rotated by the reverse input torque, by restricting the movement of the roller toward the narrow side of the wedge-shaped space, the roller does not engage with the input side member and the output side member, and the output side member is smooth. It was made to idle.

  Here, as the unlocking assisting means, it is possible to employ a means for pressing each roller in the radial direction from the cylindrical surface side of the output side member toward the cam surface side of the input side member. Specifically, each roller protrudes from one end of the cylindrical surface of the output side member, and a part of the fixing member is opposed to the protruding portion of each roller in the radial direction from the output side member side. It is preferable that an elastic member that is elastically deformed by being pressed by the rollers when the rollers are engaged with the input side member and the output side member is provided between the roller facing portion and the protruding portion of each roller. At this time, if the position of one end of the cylindrical surface of the output side member is arranged closer to the center side in the axial direction than the position of one end of the cam surface of the input side member, the entire clutch is made compact in the axial direction. be able to. The elastic member may be an O-ring or a C-shaped spring.

  On the other hand, as the locking means, the rollers are accommodated one by one in a pocket of a cage arranged between the cam surface of the input side member and the cylindrical surface of the output side member, and engaged with the cage Incorporating a sliding spring that slides with the cylindrical portion of the fixed member, when input torque is applied to the input side member, it is pushed by the cam surface of the input side member and abuts against the pocket inner surface of the cage It is possible to adopt a roller that relatively moves the roller toward the narrow side of the wedge-shaped space with a cage that receives a frictional force between the sliding spring and the fixed member.

  Alternatively, the locking means is housed one by one in a pocket of a cage in which the rollers are arranged between the cam surface of the input side member and the cylindrical surface of the output side member and engaged with the cage. When a ball sandwiched between the input side member and the fixing member is incorporated and an input torque is applied to the input side member, the ball rolls with the rotation of the input side member and is pushed by the ball. A rotational phase difference is generated between the rotating cage and the input side member, so that the roller pressed against the cam surface of the input side member and abutted against the pocket inner surface of the cage is moved between the ball and the fixing member. A cage that receives a frictional force between them may be moved relative to the narrow side of the wedge-shaped space.

  As described above, the reverse input prevention clutch of the present invention is provided with means for restricting the movement of the roller toward the narrow side of the wedge-shaped space when the output side member is rotated by the reverse input torque. Even if reverse input torque is applied in the direction opposite to the input torque before stopping during the stop in the state, the rollers do not engage the input side member and the output side member, and the output side member smoothly slips and catches The phenomenon does not occur.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 3 show a first embodiment. As shown in FIGS. 1 (a), 1 (b) and 2, the reverse input preventing clutch has an input side member 3 composed of an input shaft 1 and an outer ring 2, an output shaft 4 and an inner ring 5 formed integrally. Between the outer ring 2 and the inner ring 5, the output member 6, the housing 7 in which the plate-like mounting portion 7 b is integrally formed on the outer periphery of the cylindrical portion 7 a, and the presser cover 8 fitted on the output side. A plurality of rollers 10 arranged, a retainer 11 that holds each roller 10, a sliding spring 12 that slides on the inner peripheral surface of the housing cylindrical portion 7 a while being engaged with the retainer 11, and a presser lid 8 And an O-ring 13 as an elastic member attached to the inner cylinder portion 8a.

  The fixing member 9 rotatably supports the input shaft 1 on the inner peripheral surface of the lid portion 7c formed on the input side of the housing 7, and the output shaft 4 on the inner peripheral surface of the presser lid 8 and the cylindrical portion 8a. It is supported rotatably. An annular groove 8b into which the O-ring 13 is fitted is formed on the outer peripheral surface of the cylinder portion 8a of the presser lid 8.

  The input side member 3 includes an input shaft 1 that is a shaft portion thereof and an outer ring 2 that is an engaging portion with the roller 10, which are formed separately. Then, the input shaft 1 is fitted into the outer ring 2 by aligning the positions of the protrusions 1a formed on the outer peripheral surface of the large diameter portion of the input shaft 1 and the notches 2a of the outer ring 2 corresponding thereto. And the outer ring 2 are connected so as to be integrally rotatable. Further, about half of the inner ring 5 is rotatably fitted in the hole in the center of the large diameter portion of the input shaft 1 so that the input side member 3 and the output side member 6 rotate around the same axis. .

  Further, as shown in FIG. 3 (a), cam surfaces 2b and 2c which are inclined in opposite directions are alternately arranged in the circumferential direction on the inner circumferential surface of the outer ring 2 which is radially opposed to the outer circumferential cylindrical surface of the inner ring 5. A plurality of wedge-shaped spaces that are gradually narrowed on both sides in the circumferential direction are formed between the cylindrical surface of the inner ring 5 and the cam surfaces 2b and 2c. When the roller 10 held by the cage 11 between the outer ring 2 and the inner ring 5 is in the center of the wedge-shaped space, the roller 10 is held in a state of being detached from the outer ring 2 and the inner ring 5. .

  The cage 11 is made of a synthetic resin, and includes an annular portion 11a and a column portion 11b that is erected on the inner surface of the annular portion 11a and is inserted between the outer ring 2 and the inner ring 5, and between the column portions 11b. The rollers 10 are accommodated one by one in the formed pocket. A cutout 11c for engaging with the sliding spring 12 is formed in the annular portion 11a.

  The sliding spring 12 includes a C-shaped sliding portion 12a that slides with the inner peripheral surface of the housing cylindrical portion 7a, and hook portions 12b that extend inward from both ends of the sliding portion 12a. Is inserted into the notch 11c of the cage annular portion 11a and brought into contact with the circumferential edge thereof, thereby engaging the cage 11 in the circumferential direction. The sliding portion 12a is in contact with the inner peripheral surface of the housing cylindrical portion 7a in an elastically contracted state, and receives a sliding resistance when the cage 11 rotates integrally with the sliding spring 12. ing.

  Further, the position of the output side end of the inner ring 5 cylindrical surface is arranged closer to the center side in the axial direction than the position of the output side end of the outer ring cam surfaces 2b, 2c, and each roller 10 protrudes from the output side end of the inner ring 5 cylindrical surface. It is arranged in a state. The cylindrical portion 8a of the presser lid 8 extends to a position facing the protruding portion of each roller 10 in the radial direction, and an O-ring 13 fitted in the annular groove 8b on the outer peripheral surface of each roller 10 as described later. When the outer ring 2 and the inner ring 5 are engaged with each other, the roller 10 is pushed by the roller 10 to be elastically deformed. A C-shaped spring can be used in place of the O-ring 13.

  Next, the operation of the reverse input prevention clutch will be described. FIG. 3B shows a state when a clockwise input torque is applied to the input shaft 1 in the drawing. When the input torque is applied, the input shaft 1 and the outer ring 2 rotate together and are pushed by the cam surface 2b of the outer ring 2 (2c when the input torque is counterclockwise), and the side surface of the pillar 11b of the cage 11 ( The roller 10 in contact with the pocket inner surface is relatively moved toward the narrow side of the wedge-shaped space by the cage 11 that receives the frictional force between the sliding spring 12 and the housing cylindrical portion 7a. As a result, the roller 10 presses the O-ring 13 to engage with the outer ring 2 and the inner ring 5, and the rotation of the input shaft 1 and the outer ring 2 is transmitted to the inner ring 5 and the output shaft 4 through the roller 10. When a counterclockwise input torque is applied, rotation transmission from the input side to the output side is performed in the same manner.

  As described above, when the input of torque is interrupted while the rotation is transmitted from the input side to the output side and the entire clutch stops, the force that the outer ring 2 pushes the roller 10 and the retainer 11 push the roller 10. While the force to return is lost, the O-ring 13 that is elastically deformed by being pressed by the roller 10 causes the roller 10 to move from the cylindrical surface side of the inner ring 5 toward the outer ring cam surface 2b (or 2c) side by the elastic restoring force. It comes to press in the radial direction. For this reason, even if the roller 10 is in contact with the outer ring cam surface 2b (or 2c) and the inner ring 5 cylindrical surface, the engagement with the outer ring 2 and the inner ring 5 is released, and the roller 10 is held in this released state.

  When a reverse input torque is applied to the output shaft 4 in the stop state, the roller 10 moves to the narrow side of the wedge-shaped space by the O-ring 13 even if the direction is the reverse direction to the input torque before the stop. Therefore, the roller 10 and the outer ring 2 and the inner ring 5 are not engaged with each other. Accordingly, the inner ring 5 and the output shaft 4 run idle, and no rotation is transmitted to the outer ring 2 and the input shaft 1. Similarly, even when the direction of the reverse input torque is the same as the input torque before stopping, rotation is not transmitted to the input side.

  As described above, this reverse input prevention clutch is provided with unlocking assisting means for restraining the roller 10 so that the roller 10 does not move to the narrow side of the wedge-shaped space when the output side member 6 is rotated by the reverse input torque. Therefore, even when a reverse input torque is applied in the direction opposite to the input torque before the stop when stopped in the lock standby state, the roller 10 does not engage with the outer ring 2 and the inner ring 5, and the inner ring 5 and the output shaft 4 slips smoothly and does not cause a catching phenomenon.

  4 (a) and 4 (b) show a second embodiment. In this embodiment, the positional relationship in the radial direction between the input side member and the output side member is reversed from that of the first embodiment. In the following, differences from the first embodiment will be mainly described. This reverse input prevention clutch includes an input side member 16 in which an input shaft 14 and an inner ring 15 are integrally formed, and an output side member 19 in which an output shaft 17 and an outer ring 18 are connected so as to be integrally rotatable. The connection method of the output shaft 17 and the outer ring 18 is the same as that of the input shaft 1 and the outer ring 2 of the first embodiment. Further, the input side member 16 and the output side member 19 are configured so that the small diameter portion 15a protruding from one end surface of the inner ring 15 is rotatably fitted in the hole in the center of the large diameter portion of the output shaft 17, so It is designed to rotate. And the holder | retainer 11, the sliding spring 12, and the O-ring 13 are distribute | arranged to the input side contrary to 1st Embodiment, The presser lid 8 does not have a cylinder part.

  The inner circumference of the outer ring 18 is formed in a cylindrical surface, and cam surfaces 15b and 15c that are inclined in opposite directions are alternately provided in the circumferential direction on the outer circumferential surface of the inner ring 15 that opposes the outer ring 18 in the radial direction. Similarly to the form, a plurality of wedge-shaped spaces that are gradually narrowed on both sides in the circumferential direction are formed between the inner ring 15 and the outer ring 18.

  The position of the input side end of the cylindrical surface of the outer ring 18 is arranged closer to the center side in the axial direction than the position of the input side ends of the inner ring cam surfaces 15b, 15c, and each roller 10 protrudes from the input side end of the cylindrical surface of the outer ring 18. It is arranged in a state. When the O-ring 13 disposed between the protruding portion of each roller 10 and the inner peripheral surface of the housing cylindrical portion 7a is engaged with each roller 10, the outer ring 18 and the inner ring 15, the roller 10 It is pushed and elastically deformed. Other configurations and clutch operations are the same as those in the first embodiment.

  Therefore, in this embodiment as well, as in the first embodiment, it is possible to prevent a catching phenomenon when reverse input torque is applied to the output side member 19.

  5 (a) and 5 (b) show a third embodiment. This embodiment is based on the first embodiment. When the input torque is applied, the roller 10 is relatively moved to the narrow side of the wedge-shaped space to engage with the input side member 3 and the output side member 6. Only the configuration is changed. That is, in the first (and second) embodiment, in order to constitute the locking means, the cage 11 that holds the roller 10 and the housing cylindrical portion 7a that slides in a state of being engaged with the cage 11 are slid. Although the sliding spring 12 is incorporated, in this embodiment, the retainer 20 that holds the roller 10 and the ball 21 that is sandwiched between the outer ring 2 and the presser lid 8 while being engaged with the retainer 20 are incorporated and the lock is held. Configured means. In the annular portion 20a of the retainer 20, a plurality of circular notches 20c are formed at positions that do not overlap the column portion 20b, and the balls 21 are fitted into the notches 20c so as to be freely rollable. The ball 21 and the cage 20 are engaged in the circumferential direction.

  According to the locking means of this embodiment, when an input torque is applied to the input side member 3, the ball 21 rolls with the rotation of the outer ring 2, and the cage 20 is pushed by the ball 21 and rotates. The roller 10 that is pressed by the cam surface 2b or 2c of the outer ring 2 and abuts against the side surface (inner surface of the pocket) of the retainer 20 is The cage 20 that receives frictional force with the presser lid 8 is moved relative to the narrow side of the wedge-shaped space and presses the O-ring 13 to engage with the outer ring 2 and the inner ring 5. Since the configuration other than the locking means and the clutch operation are the same as those in the first embodiment, this embodiment can also prevent a catching phenomenon when reverse input torque is applied.

a is a front sectional view of the clutch of the first embodiment, b is a sectional view taken along the line II of a. 1 is an exploded perspective view of the clutch of FIG. a and b are principal part expanded sectional views explaining the structure and operation | movement of the clutch of FIG. 1, respectively. a is a front sectional view of the clutch of the second embodiment, and b is a sectional view taken along line IV-IV of a. a is a front sectional view of the clutch of the third embodiment, b is a sectional view taken along the line VV of a.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input shaft 2 Outer ring 2b, 2c Cam surface 3 Input side member 4 Output shaft 5 Inner ring 6 Output side member 7 Housing 8 Presser lid 9 Fixing member 10 Roller 11 Cage 12 Sliding spring 13 O-ring 14 Input shaft 15 Inner ring 15b, 15c Cam surface 16 Input side member 17 Output shaft 18 Outer ring 19 Output side member 20 Cage 21 Ball

Claims (7)

  The input side member and the output side member are arranged to rotate about the same axis, a cylindrical surface is formed on the outer peripheral side or inner peripheral side of the output side member, and the cylinder of the output side member is formed on the input side member A plurality of cam surfaces that are radially opposed to the surface are provided in the circumferential direction to form wedge-shaped spaces that are gradually narrowed in the circumferential direction between the cylindrical surface and the respective cam surfaces, and rollers are arranged in each of these wedge-shaped spaces. When an input torque is applied to the input side member, the locking means provided between the rollers and the fixing member causes the rollers to move relative to the narrow side of the wedge-shaped space, thereby causing the input side member and the output to move. By engaging with the side member, the rotation of the input side member is transmitted to the output side member, and when a reverse input torque is applied to the output side member, the output side member idles and the output side member rotates. Is prevented from being transmitted to the input side member. In the above-described configuration, there is provided reverse input prevention means provided with a lock release assisting means for restraining the rollers so that the rollers do not move to the narrow side of the wedge-shaped space when the output side member is rotated by reverse input torque. clutch.   2. The lock release assisting means presses each of the rollers in a radial direction from the cylindrical surface side of the output side member toward the cam surface side of the input side member. Reverse input prevention clutch.   The unlocking assisting means causes each roller to protrude from one end of the cylindrical surface of the output side member, and causes a part of the fixing member to face the protruding portion of each roller in the radial direction from the output side member side. An elastic member is provided between the roller facing portion of the fixing member and the protruding portion of each roller, and is elastically deformed by being pressed by the roller when each roller engages with the input side member and the output side member. The reverse input preventing clutch according to claim 2.   4. The reverse input preventing clutch according to claim 3, wherein the position of one end of the cylindrical surface of the output side member is arranged closer to the center side in the axial direction than the position of one end of the cam surface of the input side member.   The reverse input prevention clutch according to claim 3 or 4, wherein the elastic member is an O-ring or a C-shaped spring.   The locking means accommodates the rollers one by one in a pocket of a cage arranged between the cam surface of the input side member and the cylindrical surface of the output side member, and is fixed in a state of being engaged with the cage. A roller that slides against the cylindrical portion of the roller and that is pressed against the cam surface of the input side member when the input torque is applied to the input side member, contacts the inner surface of the pocket of the cage. The reverse input according to any one of claims 1 to 5, wherein a cage that receives a frictional force between the sliding spring and the fixing member is moved relative to the narrow side of the wedge-shaped space. Prevent clutch.   The locking means accommodates the rollers one by one in a pocket of a cage arranged between the cam surface of the input side member and the cylindrical surface of the output side member, and engages with the cage in the input side. When a ball sandwiched between a member and a fixed member is incorporated and an input torque is applied to the input side member, the ball rolls with the rotation of the input side member and is pushed by the ball to rotate. A rotational phase difference is generated between the cage and the input side member, so that the roller pressed against the cam surface of the input side member and abutted against the pocket inner surface of the cage is moved between the ball and the fixing member. The reverse input prevention clutch according to any one of claims 1 to 5, wherein a cage that receives a frictional force is relatively moved toward a narrow side of the wedge-shaped space.

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