JP6633277B2 - One-way clutch and reverse input prevention clutch - Google Patents

Description

  The present invention relates to a one-way clutch and a reverse input prevention clutch in which rolling elements serving as engaging elements are incorporated in a state of contacting each other.

  The one-way clutch is provided with a plurality of cam surfaces inclined in one predetermined direction on one of an inner peripheral surface of the outer member and an outer peripheral surface of the inner member, and uses the other as a cylindrical surface to form the outer member and the inner member. A plurality of wedge-shaped spaces narrowing on one side in the circumferential direction are formed therebetween, and rolling elements serving as engaging elements are housed in the respective wedge-shaped spaces, and each of the rolling elements is pushed into a narrow portion of the wedge-shaped space by an elastic member ( By engaging with the outer member and the inner member), when one of the outer member and the inner member rotates in a predetermined direction, both members are locked and torque is transmitted to the other member. In many cases, when one of the members rotates in the opposite direction, the locked state of both members is released, and only one of the members idles.

  Some one-way clutches described above incorporate all rolling elements in contact with each other in order to increase the number of rolling elements and increase the torque transmission capability (the rolling elements are rollers). Is called a full complement form). For the full-roller type one-way clutch, an elastic member that pushes each roller into the narrow portion of the wedge-shaped space is easy to be incorporated into the clutch and is not easily damaged. A C-shaped spring is arranged between the inner members so as to extend along the arrangement of the rollers. In a state where the diameter of the C-shaped spring is reduced, a hook provided at one end of the C-shaped spring is connected to the outer member or the inner member. It has been proposed that a hook portion provided at the other end be engaged with one of the rollers so as to abut one of the rollers (see Patent Document 1).

  On the other hand, the reverse input prevention clutch transmits the rotation to the output member when the input torque is applied to the input member, and prevents the input member from rotating when the reverse input torque is applied to the output member. This is a clutch having a function.

  As a specific configuration of the reverse input prevention clutch, for example, a torque transmission for transmitting the rotation of the input member to the output member with a slight angle delay between the input member and the output member rotating around the same axis. Means, a plurality of cam surfaces inclined in one predetermined direction and a plurality of cam surfaces inclined in the other direction are continuously provided on the outer peripheral surface of the output member, and a fixing member having a cylindrical surface facing each of these cam surfaces is provided. A plurality of first wedge-shaped spaces narrowing on one side in the circumferential direction and a plurality of second wedge-shaped spaces narrowing on the other side in the circumferential direction are continuously formed between the output member and the fixing member; A coil spring as an elastic member is provided in each wedge-shaped space, in which rollers as rolling elements serving as engagement elements are housed in contact with each other, and each roller is pushed into a narrow portion of the first or second wedge-shaped space. The narrow part of the wedge-shaped space and the second wedge Narrow portion between the at opposite positions in the circumferential direction, there is obtained by inserting the column portion of the linked cage to rotate integrally with the input member (see Patent Document 2.).

  In the reverse input prevention clutch described in Patent Document 2, each roller is pushed into the narrow portion of the first or second wedge-shaped space by the elastic force of the coil spring, and is engaged with the fixed member and the output member. Therefore, no matter which direction the reverse input torque is applied to the output member, the output member is locked by the fixed member, and the input member does not rotate. On the other hand, when input torque is applied to the input member, regardless of the direction in which the input member rotates, the column of the retainer, which rotates integrally with the input member, opposes in the rotation direction by the elasticity of the coil spring. After the output member is released from the locked state by pushing it to the wide side of the first or second wedge-shaped space against the force, the output member is transmitted by the torque transmitting means provided between the input member and the output member. , And the output member rotates.

Japanese Patent No. 3989702 Japanese Patent No. 4806264

  By the way, in the one-way clutch of Patent Document 1, hooks that extend linearly in the clutch axial direction are provided at both ends of a C-shaped spring, and the other end hooks are in contact with the cam surface over the entire length of the roller. Since it is designed to press one, the rollers cannot be pressed near the pitch circle of the arrangement, and when one of the outer member and the inner member rotates in a predetermined direction, The locking operation of both members may become unstable and the rotation of the other member may change irregularly.

  Further, when the member provided with the cam surface of the outer member and the inner member rotates in a direction opposite to the predetermined direction, the other end side hook portion of the C-shaped spring causes the roller and the cam surface to be in contact with each other. When the member is engaged between the cam surfaces, the member on the cam surface side cannot rotate idly, and the other member may rotate in the same direction.

  On the other hand, if the C-shaped spring is formed of a thick wire (a round wire having a large wire diameter or a square wire having a large side), the position at which the other end side hook portion contacts the rollers approaches the pitch circle of the rollers, As described above, the lock failure between the outer member and the inner member and the engagement of the hook portion on the other end hardly occur. However, since the secondary moment of area of the C-shaped spring increases and the spring constant increases, The dimensional error causes a large variation in the idling torque.

  On the other hand, in the reverse input prevention clutch disclosed in Patent Document 2, a coil spring is incorporated at a position where the wide portion of the first wedge-shaped space and the wide portion of the second wedge-shaped space are circumferentially opposed to each other. If the torque transmission capacity is increased by increasing the number, the installation space for the coil spring cannot be increased. Therefore, in order to obtain a stable locking operation when a reverse input torque is applied to the output member, it is necessary to use a coil spring having a relatively large spring constant. However, if the spring constant of the coil spring is large, an input torque is applied to the input member, so that the pillar portion of the retainer pushes the rollers toward the wide side of the first or second wedge-shaped space, and the output member and the fixed member When releasing the locked state, there is a problem that the force required to compress the coil spring by the amount of movement of the rollers increases, and the rotational torque tends to increase.

  Accordingly, the present invention provides a one-way clutch and a reverse input prevention clutch in which rolling elements serving as an engaging element are incorporated in a state in which they contact each other, while ensuring the stability of the clutch operation while maintaining the stability of the clutch operation and the idling torque of the one-way clutch. It is an object to reduce the rotational torque of an input prevention clutch.

  In order to solve the above-described problems, the present invention provides a method in which a plurality of cam surfaces inclined in one predetermined direction are continuously provided on one of an inner peripheral surface of an outer member and an outer peripheral surface of an inner member, and the other is a cylindrical surface. A plurality of wedge-shaped spaces which are narrowed on one side in the circumferential direction are continuously formed between the outer member and the inner member, and the rolling elements are accommodated in the respective wedge-shaped spaces in contact with each other, and A C-shaped spring extending along the arrangement of the rolling elements is disposed between the side member and the inner member, and one end of the C-shaped spring is connected to the outer member or the inner member in a state where the diameter of the C-shaped spring is reduced. The hooks provided at the other end are brought into contact with one of the rolling elements, and each of the rolling elements is pushed into a narrow portion of the wedge-shaped space by the elastic force of the C-shaped spring. In the directional clutch, a configuration is employed in which the hook at the other end of the C-shaped spring is curved.

  That is, for a one-way clutch in which rolling elements are assembled in contact with each other, a hook portion provided at the other end of a C-shaped spring whose one end is locked and in contact with one of the rolling elements is curved. By forming it in the form, the hook portion can press the rolling elements around the pitch circle of the array of the rolling elements, and the locking operation of the two members when transmitting torque between the outer member and the inner member When the outer member or the inner member is to be idled, biting of the hook at the other end of the C-shaped spring is less likely to occur, so that a smooth idling operation can be obtained. It is. Further, as a result, the C-shaped spring can be formed of a wire rod having a small (small) spring constant, so that it is possible to suppress a variation in the idling torque due to a dimensional error of each component.

  Here, if the hook portion at the other end of the C-shaped spring is brought into contact with one of the rolling elements at at least two points near the pitch circle of the array of the rolling elements, the outer member and the inner member are formed. Can further enhance the stability of the locking operation, and the hook at the other end side hook portion of the C-shaped spring can be more reliably prevented.

  Further, according to the present invention, a torque transmitting means for transmitting the rotation of the input member to the output member with a slight angle delay is provided between the input member and the output member which rotate around the same axis, and an outer periphery of the output member is provided. On the surface or inner peripheral surface, a plurality of cam surfaces inclined in one predetermined direction and cam surfaces inclined in the other direction are respectively provided continuously, and a fixing member having a cylindrical surface facing each of these cam surfaces is provided. A plurality of first wedge-shaped spaces narrowing on one side in the circumferential direction and a plurality of second wedge-shaped spaces narrowing on the other side in the circumferential direction are continuously formed between the output member and the fixing member, respectively. An elastic member that accommodates the rolling elements in the wedge-shaped space in contact with each other and pushes each of the rolling elements into a narrow portion of the first or second wedge-shaped space is provided, and a narrow portion of the first wedge-shaped space and a second member are provided. At the position where the narrow part of the wedge-shaped space of In a reverse input prevention clutch in which a pillar of a retainer connected so as to rotate integrally with an input member is inserted, the elastic member may extend along the arrangement of the rolling elements between the output member and the fixed member. The C-shaped springs are arranged so that hooks provided at both ends thereof are brought into contact with one of the rolling elements in an elastically reduced state, and the hooks at both ends of the C-shaped spring are bent. Configuration was adopted.

  That is, for a reverse input prevention clutch in which rolling elements are incorporated in a state of contact with each other, a C-shaped spring in which hook portions at both ends contacting one of the rolling elements are curved as elastic members for pressing the rolling elements. By using this, a stable locking operation can be obtained with respect to the reverse input torque. As a result, the spring constant can be set smaller than in the case of using the conventional coil spring, and the force required to release the locked state between the output member and the fixed member can be reduced, so that the rotational torque is reduced. Can be.

  Further, if the hook portions at both ends of the C-shaped spring are brought into contact with one of the rolling elements at at least two points near the pitch circle of the array of the rolling elements, the stability of the locking operation against the reverse input torque is improved. Can be further increased.

  As described above, the one-way clutch of the present invention uses the C-shaped spring in which the hook portion abutting against one of the rolling elements uses a curved C-shaped spring. Since it is designed to be able to be pressed, the stability of the locking operation is high, and the hook portion of the C-shaped spring is hardly caught, so that a smooth idling operation can be obtained. In addition, as a result, the spring constant of the C-shaped spring can be set to be small, and the variation in the idling torque due to the dimensional error of each part can be suppressed.

  In addition, the reverse input prevention clutch of the present invention uses a C-shaped spring in which hook portions at both ends contacting one of the rolling elements are curved as elastic members for pressing the rolling elements. , While ensuring the stability of the locking operation with respect to, the spring constant is set smaller than in the case of using the conventional coil spring, and the rotational torque can be reduced.

Longitudinal front view of the one-way clutch according to the first embodiment. Sectional view along the line II-II in FIG. a and b are cross-sectional views each showing a modified example of the hook on the other end side of the C-shaped spring. Longitudinal front view of a reverse input prevention clutch according to a second embodiment. FIG. 4 is a sectional view taken along the line VV in FIG. 4.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 and 2 show a one-way clutch according to a first embodiment. In the one-way clutch, a plurality of cam surfaces 1a that are inclined in one predetermined direction are continuously provided on an inner peripheral surface of an outer ring (outer member) 1 and a rotating shaft (inner member) 2 that is passed through the outer ring 1 is provided. A plurality of wedge-shaped spaces 3 narrowing on one side in the circumferential direction are continuously formed between the outer ring 1 and the rotation shaft 2 with the outer peripheral surface being a cylindrical surface, and rollers (rolling elements serving as engaging elements) are formed in each of the wedge-shaped spaces 3. The rollers 4 are housed in contact with each other, and each roller 4 is pushed into a narrow portion of the wedge-shaped space 3 by a C-shaped spring 5 arranged so as to extend along the arrangement of the rollers 4 between the outer ring 1 and the rotating shaft 2. It is a complete roller type.

  A plurality of ridges 1b extending in the axial direction are integrally formed on the outer peripheral surface of the outer race 1 as torque transmitting means. In addition, a locking groove 1c for locking one end of the C-shaped spring 5 is provided at one location in the circumferential direction on the inner circumferential surface of the outer race 1 as described later.

  The C-shaped spring 5 is formed of a round wire, and has hook portions 5a and 5b extending at both ends thereof along the clutch axial direction. The hook portion 5a at one end is formed so as to extend linearly, and the hook portion 5b at the other end is formed so as to be bent in a substantially rectangular shape in a cross section in the clutch radial direction.

  In the C-shaped spring 5, the hook portion 5 a at one end is locked by one side wall of the locking groove 1 c of the outer ring 1 while the diameter of the C-shaped spring 5 is reduced, and the hook portion 5 b at the other end is engaged with the outer ring 1. The outer peripheral surface of the roller 4 arranged near the other side wall of the retaining groove 1c is incorporated so as to abut at two points near the pitch circle P1 of the arrangement of the rollers 4. As a result, the pressing force due to the elastic force of the C-shaped spring 5 is transmitted from the roller 4 in contact with the C-shaped spring 5 to all the other rollers 4, and each roller 4 is pushed into the narrow portion of the wedge-shaped space 3. The outer ring 1 and the rotating shaft 2 are engaged with each other.

  This one-way clutch has the above configuration, and when input torque is applied to the rotating shaft 2, when the rotating shaft 2 rotates clockwise in FIG. 1, the outer race 1 and the rotating shaft 2 When the torque of the rotating shaft 2 is locked and transmitted to the outer ring 1, and the rotating shaft 2 rotates counterclockwise, the locked state of the outer ring 1 and the rotating shaft 2 is released, and only the rotating shaft 2 idles. Conversely, when the input torque is applied to the outer ring 1, when the outer ring 1 rotates counterclockwise, torque is transmitted to the rotating shaft 2, and when the outer ring 1 rotates clockwise, the outer ring 1 and each roller 4 The C-shaped spring 5 idles integrally.

  Here, in this one-way clutch, the other end side hook portion 5b of the C-shaped spring 5 is formed in a curved form, and the rollers 4 are pressed at two points near the pitch circle P1 of the arrangement of the rollers 4, When a conventional C-shaped spring is used, both members for transmitting torque between the outer ring 1 and the rotating shaft 2 are compared with the case where the other end side hook portion presses the rollers near the cam surface over the entire length. When the outer ring 1 or the rotating shaft 2 is to be idled, the locking of the other end side hook portion 5b of the C-shaped spring 5 is unlikely to occur, and a smooth idling operation is performed. can get. Further, as a result, since the C-shaped spring 5 can be formed of a wire having a small (thin) spring constant, there is also an advantage that variations in idling torque due to dimensional errors of each component are small.

  FIG. 3 shows a modification of the hook 5b on the other end of the C-shaped spring 5. 3 (a) shows an example in which the other end side hook portion 5b is bent in a substantially annular shape and abuts the roller 4 at two points as in the example of FIG. 2, and FIG. 3 (b) shows another example. This is an example in which the end hook portion 5b is curved in a wave shape and abuts on the roller 4 at three points. If the number of places where the other end side hook portion 5b of the C-shaped spring 5 comes into contact with the rollers 4 near the pitch circle P1 in the arrangement of the rollers 4 is two or more as in these examples, the contacting point is one. It is preferable because the stability of the locking operation between the outer ring 1 and the rotating shaft 2 is improved as compared with the case where only the point is used.

  4 and 5 show a reverse input prevention clutch according to a second embodiment. This reverse input prevention clutch includes an input shaft (input member) 11, an output member 14 including an output shaft 12 and an inner ring 13, a fixing member 18 including a housing 15, an outer ring 16 and a holding lid 17, an inner ring 13 and an outer ring 16, And a roller (rolling element serving as an engagement element) 20 that is incorporated between the two column portions 19a of the retainer 19; And two C-shaped springs 21 arranged so as to extend along the arrangement of the rollers 20 therebetween.

  The input shaft 11 is provided with an engaging portion 11a having a two-sided width portion near the distal end thereof. The engaging portion 11a is inserted into an engaging hole 13a provided at the center of the inner ring 13 and has a small diameter distal end. The portion 11b is fitted into a shaft hole 12a provided at the center of the end face of the output shaft 12, and rotates around the same axis as the output shaft 12.

  The output member 14 connects the output shaft 12 and the inner ring 13 so as to rotate integrally. In the engagement hole 13a of the inner ring 13, there is formed a two-plane width portion facing the two-plane width portion of the engagement portion 11a of the input shaft 11 with a slight gap, and the rotation of the input shaft 11 is slightly reduced. The rotation is transmitted to the inner ring 13 and the output shaft 12 with an appropriate angle delay.

  The fixing member 18 is formed by sequentially fitting an outer ring 16 and a holding lid 17 on the inner periphery of the housing 15. The outer ring 16 is non-rotatably restrained by the housing 15 and is prevented from coming off by the presser lid 17.

  The retainer 19 is provided with a column portion 19a at a position opposite to a periphery of a disk portion 19b through which the input shaft 11 passes, and the disk portion 19b is fitted to the outer periphery of the engaging portion 11a of the input shaft 11. It is fixed and rotates integrally with the input shaft 11.

  Further, as shown in FIG. 4, a plurality of cam surfaces 13b inclined in one predetermined direction and a plurality of cam surfaces 13c inclined in the other direction are continuously provided on the outer peripheral surface of the inner race 13, whereby A plurality of first wedge-shaped spaces 22a narrowing on one side in the circumferential direction and a plurality of second wedge-shaped spaces 22b narrowing on the other side in the circumferential direction are formed between the inner ring 13 and the outer ring 16, respectively. I have. The rollers 20 are accommodated in the continuous wedge-shaped spaces 22a and 22b in a state where the rollers 20 are in contact with each other, and are held at positions where the narrow portion of the first wedge-shaped space 22a and the narrow portion of the second wedge-shaped space 22b face each other in the circumferential direction. The column 19a of the container 19 is inserted.

  Each of the C-shaped springs 21 is formed of a round wire, and has hook portions 21a at both ends thereof extending in the clutch axial direction and curved in a substantially rectangular shape in the clutch radial cross section. . Then, in a state where the hook portion 21a at one end is housed in the first wedge-shaped space 22a and the hook portion 21a at the other end is housed in the second wedge-shaped space 22b in a state where the diameter is reduced elastically. Each of the rollers 20 is assembled so as to abut at two points near the pitch circle P2 of the arrangement of the rollers 20. Thereby, each C-shaped spring 21 pushes each roller 20 into the narrow portion of the first or second wedge-shaped space 22a, 22b by its elastic force.

  This reverse input prevention clutch has the above-described configuration, and each roller 20 is pushed into the narrow portion of the first or second wedge-shaped space 22a, 22b by the elastic force of the C-shaped spring 21, and the outer ring 16 and the inner ring 13 Because of the engagement, the output member 14 is locked to the fixed member 18 and the input shaft 11 does not rotate even if a reverse input torque in any direction is applied to the output shaft 12.

  On the other hand, when an input torque is applied to the input shaft 11, no matter what direction the input shaft 11 rotates, the column 19 a of the retainer 19 that rotates integrally with the input shaft 11 faces in the rotation direction. The output member 14 is released from the locked state by pushing out the first or second wedge-shaped space 22a, 22b toward the wide side of the first or second wedge-shaped space 22a, 22b against the elastic force of the C-shaped spring 21. Then, when the input shaft 11 further rotates and the two-plane width portion of the engagement portion 11 a engages with the two-plane width portion of the engagement hole 13 a of the inner ring 13, the rotation of the input shaft 11 is output via the inner ring 13. It is transmitted to the shaft 12.

  Here, in this reverse input prevention clutch, a C-shaped spring 21 is used as an elastic member that presses the rollers 20 incorporated in a state of contact with each other, and hook portions 21a at both ends thereof are formed in a curved form. Since the hook portions 21a press the rollers 20 at two points near the pitch circle P2 in the arrangement of the rollers 20, the stability of the locking operation against the reverse input torque is ensured, while the hooks 21a are different from the case of using the conventional coil spring. The rotational torque can also be reduced by setting the spring constant small.

  Further, since the hook portions 21a at both ends of the C-shaped spring 21 are hard to bite between the rollers 20 and the cam surfaces 13b and 13c of the inner ring 13 due to the curved shape, the input torque is applied to the input shaft 11. When released, the column portion 19a of the retainer 19 smoothly pushes the rollers 20 to the wide side of the first or second wedge-shaped spaces 22a, 22b to release the locked state of the output member 14 and the fixed member 18. Can be.

  Furthermore, the hook portions 21a at both ends of the C-shaped spring 21 are only inserted in the space where the wide portion of the first wedge-shaped space 22a and the wide portion of the second wedge-shaped space 22b face each other in the circumferential direction. As compared with the case where a conventional coil spring is incorporated, the amount of movement of the roller 20 when the pillar portion 19a of the retainer 19 pushes the roller 20 is set to be larger, so that the locked state of the output member 14 and the fixed member 18 can be released. It can be performed more reliably.

  In each of the above-described embodiments, the one-way clutch and the reverse input prevention clutch using the rollers 4 and 20 as the rolling elements serving as the engagement members have been described. However, the present invention uses a ball or the like other than the rollers as the rolling elements. Of course, the present invention can be applied to a one-way clutch or a reverse input prevention clutch.

  Further, in the one-way clutch of the present invention, the arrangement of the cam surface and the cylindrical surface is reversed from that of the first embodiment, the cam surface is provided on the outer peripheral surface of the inner member, and the inner peripheral surface of the outer member is set as the cylindrical surface. Is also good. On the other hand, in the reverse input prevention clutch of the present invention, the arrangement of the output member and the fixed member is reversed from that of the second embodiment, and the fixed member having the outer peripheral cylindrical surface inside the output member provided with the cam surface on the inner peripheral surface. May be arranged.

1 outer ring (outer member)
1a Cam surface 2 Rotary shaft (inner member)
3 wedge-shaped space 4 rollers (rolling element)
5 C-shaped springs 5a, 5b Hook 11 Input shaft (input member)
11a engaging portion 12 output shaft 13 inner ring 13a engaging holes 13b, 13c cam surface 14 output member 15 housing 16 outer ring 17 holding lid 18 fixing member 19 retainer 19a pillar portion 20 roller (rolling element)
21 C-shaped spring 21a Hook portion 22a First wedge-shaped space 22b Second wedge-shaped space P1, P2 Pitch circle

Claims (3)

A plurality of cam surfaces inclined in one predetermined direction are continuously provided on one of an inner peripheral surface of the outer member and an outer peripheral surface of the inner member, and the other is a cylindrical surface, and the cam surface is provided between the outer member and the inner member. A plurality of wedge-shaped spaces that are narrowed on one side in the circumferential direction are continuously formed, and the rolling elements are accommodated in the respective wedge-shaped spaces in contact with each other, and the rolling elements are provided between the outer member and the inner member. A C-shaped spring extending along the arrangement of the above is arranged, and one end of the C-shaped spring is engaged with the outer member or the inner member while the diameter of the C-shaped spring is reduced, and a hook portion provided at the other end is provided. Is brought into contact with one of the rolling elements, and each of the rolling elements is pushed into a narrow portion of the wedge-shaped space by the elastic force of the C-shaped spring. a hook portion, to one of the rolling elements at least two points in the vicinity of the pitch circle of the sequence before Kiten body those As to the one-way clutch, characterized in that it is curved in a plane including the tangential line of the outer periphery of the rolling element.   A torque transmitting means for transmitting the rotation of the input member to the output member with a slight angle delay is provided between the input member and the output member rotating around the same axis, and the outer peripheral surface or the inner peripheral surface of the output member is provided. A plurality of cam surfaces inclined in one predetermined direction and a plurality of cam surfaces inclined in the other direction are continuously provided, and a fixing member having a cylindrical surface facing each of the cam surfaces is provided, and the output member and the fixing member are provided. In between, a plurality of first wedge-shaped spaces narrowing on one side in the circumferential direction and a plurality of second wedge-shaped spaces narrowing on the other side in the circumferential direction are respectively formed continuously, and rolling elements are provided in the respective wedge-shaped spaces. An elastic member is provided which is housed in contact with each other and pushes each rolling element into the narrow portion of the first or second wedge-shaped space, and the narrow portion of the first wedge-shaped space and the narrow portion of the second wedge-shaped space are provided. Is integrated with the input member at the position where In the reverse input prevention clutch in which a pillar portion of a retainer connected to roll is inserted, the elastic member is disposed so as to extend along the arrangement of the rolling elements between the output member and the fixed member, In the reduced diameter state, a C-shaped spring is used in which hooks provided at both ends thereof are brought into contact with one of the rolling elements, and the hooks at both ends of the C-shaped spring are curved. And reverse input prevention clutch. The reverse input prevention clutch according to claim 2 , wherein the hook portions at both ends of the C-shaped spring abut against one of the rolling elements at at least two points near a pitch circle of the array of the rolling elements. .

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