Reverse input cutoff clutch

Abstract

To provide a reverse input cutoff clutch in which a clutch strength is improved and a size is reduced to a compact size, and an output member can be rotated even in an emergency or an abnormal situation.SOLUTION: A clutch includes: an away movement mechanism in which an input of a torque into an input member moves a first brake member and a second brake member in a direction closer to a relatively radial direction, and the first brake member and the second brake member are moved in a direction away from a stationary member; and a transmission mechanism for transmitting the torque input in the input member in a state where the first brake member and the second brake member are away from the stationary member to the output member. A cam member is interposed between the first brake member and the second brake member, a rotation of a reverse input of torque into the output member is transmitted to the cam member, the first brake member and the second brake member are moved away in a radial direction to each other, the first brake member and the second brake member are pressed against the stationary member, and the transmission of the torque from the output member to the input member is cut off.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a reverse input disconnecting clutch. [Background technology]

[0002] As shown in Fig. 28, the reverse input cutoff clutch is a clutch that transmits the rotation of the input member 2 to the output member 3 when input torque is applied, and prevents the input member 2 from rotating in response to reverse input torque. Such a reverse input cutoff clutch is described, for example, in Patent Document 1.

[0003] In the reverse input cutoff clutch described in Patent Document 1, when torque is reversely input to the output member 3, the output member 3 moves a pair of engaging members (engagements) 5, 5 radially outward, thereby pressing the pressing surfaces 11, 11 of the engaging members 5, 5 against the pressed surface 10 (inner diameter surface consisting of a cylindrical surface) of the pressed member 4, thereby cutting off the torque. Furthermore, when torque is input to the input member 2, the pair of engaging members 5, 5 move radially inward, thereby moving the pressing surfaces 11, 11 of the engaging members 5, 5 away from (separating from) the pressed surface 10 of the pressed member 4. The torque input to the input member 2 is transmitted to the output member 3 via the engaging members 5, 5.

[0004] JIS B 8433-1 (2015) stipulates in sections "5.5.2 Emergency Stop" and "5.13 Movement without Drive Power" that industrial robots must have an emergency stop function and must be designed so that axes can move without drive power in an emergency or abnormal situation.

[0005] For this reason, many actuators that move the joints of robots incorporate electromagnetic brakes as emergency stop mechanisms (hereinafter also referred to as "brakes"). Generally, during normal robot operation, electromagnetic brakes are released by using the attractive force of an electromagnet to attract the armature, compressing the brake spring and releasing a brake plate attached to the output shaft so that it cannot rotate relative to the output shaft but can move axially. During a power outage, the attractive force of the electromagnet disappears, causing the brake spring to press the brake plate against a fixed member via the armature, braking the output shaft through frictional forces between the armature and the brake plate and between the brake plate and the fixed member. Even during a power outage, the brake can be released and the output shaft can be moved manually by supplying power from an auxiliary power source such as a battery.

[0006] However, in robots that use actuators incorporating electromagnetic brakes like those described above, the electromagnetic brakes must be constantly energized and released during operation, resulting in the problem of high power consumption. Also, because wiring for the electromagnetic brake is required for each actuator, the more joints a robot has, the more wiring there will be, which creates the problem of a complex structure.

[0007] Furthermore, when braking the output shaft during a power outage, friction powder is generated between the armature and brake plate, and between the brake plate and fixed member, and this friction powder may adversely affect the operation of the reducer and rotation sensor (encoder) built into the actuator.In order to protect the reducer and rotation sensor from wear powder, it has been proposed to arrange the components that make up the actuator in the following order: reducer-motor-brake (electromagnetic brake)-rotation sensor.However, if this arrangement is adopted, it will be impossible to standardize the connection structure between the motor and rotation sensor, as with actuators that do not require a brake and are arranged in the following order: reducer-motor-rotation sensor.

[0008] A conventional electromagnetically actuated brake with a manual release device equipped with a manual release lever has been disclosed (Patent Document 2). In this case, the manual release lever is formed so that it can be attached to and detached from the field core by elastically deforming so that the distance between its two ends increases, and pressing portions are provided near both ends of the manual release lever that are supported by the field core, which press the armature toward the field core when the manual release lever is turned.

[0009] That is, in the non-excitation operating brake, the rotating end of the manual release lever is formed so as to be located outside the field core when viewed from the axial direction of the rotating shaft, and the part of the field core that supports the manual release lever is composed of an axial hole into which the support shafts that form both ends of the manual release lever are inserted so as to be freely inserted and removed, and a recessed groove that is formed shallower than this axial hole and extends from this axial hole along the outer surface of the field core, and the recessed groove is formed so as to gradually move away from the armature as it approaches the end of the field core that is closest to the rotating end of the manual release lever when viewed from the axial direction when the manual release lever rotates. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] International Publication No. 2021 / 172558 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-2617 Summary of the Invention [Problem to be solved by the invention]

[0011] In the device described in Patent Document 1, a gap is provided between the output member 3 and the engaging members 5, 5 to allow the engaging members 5, 5 to separate from the pressed member 4. In other words, there is a so-called backlash (play). The size of the backlash is determined by the size of the gap and the distance from the center of rotation of the contact portion X of the output member 3 and the engaging members 5, 5. In this case, the distance r (see FIG. 27) from the center of rotation O of the contact portion X is short, and the backlash that occurs is large. If the "backlash" is large, it may cause abnormal noise.

[0012] That is, in the clutch described in Patent Document 1, when rotational torque is input to the input member 2, the input-side engaging portion 7 rotates inside the input-side engaged portion 12 in the rotational direction of the input member 2. Then, the radially inner surface of the input-side engaging portion 7 presses the radially inner portion of the inner surface of the input-side engaged portion 12 radially inward. In this case, each engaging element 5 elastically contracts the pair of springs 18, moving in a direction away from the pressed surface 10. Then, the output-side engaged surface 16 of each engaging element 5 comes into surface contact with both sides of the output-side engaging portion 9 of the output member 3 in the lateral direction. As a result, the rotational torque input to the input member 2 is transmitted to the output member 3 via the pair of engaging elements 5.

[0013] When a rotational torque is reversely input to the output member 3, the reverse input cutoff clutch 1 moves each of the engaging elements 5 in a direction approaching the pressed surface 10, regardless of the rotational direction of the output member 3. Then, the rotational torque reversely input to the output member 3 is completely cut off and not transmitted to the input member 2, or only a portion of the rotational torque reversely input to the output member 3 is transmitted to the input member 2, with the remainder being cut off. In other words, when a rotational torque is reversely input to the output member 3, the output-side engaging portion 9 rotates in the rotational direction of the output member 3, inside the pair of output-side engaged portions 13. Then, the corners of the output-side engaging portion 9 press the output-side engaged surface 16 radially outward. As a result, each of the engaging elements 5 moves in a direction approaching the pressed surface 10, and the engaging elements 5 move radially outward, away from each other, based on their engagement with the output member 3.

[0014] In order to cut off the reverse input, the reverse input torque must be smaller than the brake torque. In other words, the following equation 1 must be satisfied:

number

[0015] In this case, it is necessary to reduce the distance r from the contact point X between the output member 2 and the engaging member 5 to the center of rotation O. However, if the distance r (see FIG. 29) is reduced, the load acting on the output member 23 increases, causing durability problems. Furthermore, to satisfy the relationship of the above equation (1), if the distance from the center of rotation O to the contact point C (see FIG. 28) between the engaging member 5 and the pressed member 4 is R (see FIG. 28), then the distance R needs to be increased. However, if the distance R is increased, the outer diameter of the reverse input cutoff clutch increases, which makes it impossible to make it compact, makes it difficult to install, and increases its weight.

[0016] Furthermore, the non-excitation operating brake described in Patent Document 2 has a large number of parts, which makes it difficult to assemble, resulting in high overall costs.

[0017] Therefore, in consideration of the above problems, the present invention provides a reverse input cut-off clutch that has increased clutch strength, is compact, and is capable of rotating the output member in an emergency or abnormality. [Means for solving the problem]

[0018] The reverse input disconnect clutch of the present invention is a reverse input disconnect clutch having an input member to which torque is input, an output member to which torque is output, a first braking member and a second braking member capable of reciprocating in a radial direction, and a stationary member arranged radially outside the first braking member and the second braking member, and further comprising a separating movement mechanism that, when torque is input to the input member, moves the first braking member and the second braking member in a direction to approach each other in the radial direction and moves the first braking member and the second braking member in a direction to move them away from the stationary member, and a separating movement mechanism that moves the first braking member and the second braking member in a direction to move them away from the stationary member when torque is input to the input member while the first braking member and the second braking member are away from the stationary member. and a transmission mechanism that transmits torque to an output member, the cam member being interposed between the first brake member and the second brake member, such that when torque is input in reverse to the output member, the rotational motion is transmitted to the cam member, causing the first brake member and the second brake member to move in a direction radially away from each other, and the first brake member and the second brake member to be pressed against the stationary member, thereby blocking the transmission of torque from the output member to the input member, and further comprising a release mechanism that restricts the relative rotation of the output member and the cam member and releases the blockage of the transmission of torque from the output member to the input member.

[0019] According to the reverse input cutoff clutch of the present invention, when torque is input to the input member, the pair of brake members separate from the stationary member. In this separated state, the torque input to the input member is transmitted to the output member, causing the output member to rotate. Furthermore, when torque is input reversely to the output member, the cam member rotates, causing the first and second brake members to separate relatively. This presses the first and second brake members against the stationary member, blocking the transmission of torque from the output member to the input member. The first and second brake members separate relatively by rotation of the cam member interposed between the first and second brake members. At this time, the cam member restricts the first and second brake members from approaching each other, effectively preventing the pair of brake members from separating from the stationary member. Furthermore, when the first and second brake members are relatively separated, the end of the cam member facing the first brake member contacts the first brake member, the end of the cam member facing the second brake member contacts the second brake member, and if the end of the cam member facing the first brake member rotates counterclockwise, the end of the cam member facing the second brake member also rotates counterclockwise. In this case, the end of the cam member facing the first brake member presses the first brake member toward the opposite side of the second brake member, and the end of the cam member facing the second brake member presses the second brake member toward the opposite side of the first brake member. Therefore, by setting the distance between the first contact portion on the cam member side that contacts the first brake member and the second contact portion on the cam member side that contacts the second brake member relatively long, the angle of rotation of the cam member between the first and second brake members is reduced, thereby reducing backlash of the output member. Furthermore, the load acting on the cam member can be reduced, thereby increasing the strength of the clutch.

[0020] Furthermore, even if the distance from the contact point between one braking member and the cam member to the rotation center O is long, the reverse input torque can be made smaller than the braking torque without increasing the distance from the rotation center O to the braking member and the stationary member. As a result, the outer diameter of this clutch does not need to be large.

[0021] Furthermore, a release mechanism is provided to release the interruption of the transmission of torque from the output member to the input member, so that the brake can be released in the event of a power outage, etc., and the output member can be rotated manually. In this case, by restricting the relative rotation of the output member and the cam member, the output member can be rotated manually, which has the advantage of not being complicated as a mechanism.

[0022] The output member has an output shaft portion disposed coaxially with the axis of the input shaft portion of the input member, and an arm portion extending radially from the output shaft portion, and the cam member has a cam main body portion extending radially and having one radial end connected to the radially outer diameter side end of the arm portion of the output member, and a protrusion portion provided on the cam main body portion and disposed between the first braking member and the second braking member, and the cam main body can be configured so that when torque is reversely input to the output member, the connecting portion of the arm portion swings around the output shaft portion of the output member, and the pair of first contact portion and second contact portion of the protrusion portion press the brake member pressed surfaces of the first braking member and the second braking member, respectively, and move in directions radially apart from each other.

[0023] With this configuration, the output member has an output shaft portion that is coaxial with the input shaft portion of the input member, allowing the output member to rotate stably without wobbling when torque is input to the input member. Furthermore, when torque is input in reverse to the output member, the connecting portion of the arm portion of the cam main body swings around the output shaft portion of the output member, causing the pair of first and second contact portions of the protrusion to press the first and second brake members, respectively, and move in a direction away from each other in the radial direction. This allows the first and second brake members to slide stably in a direction away from each other, i.e., radially outward. When the first and second brake members slide in a direction away from each other, they are pressed against the stationary member, thereby blocking the transmission of torque from the output member to the input member. This allows the state in which torque transmission to the input member is blocked to be stably achieved.

[0024] The release mechanism can be configured by providing through holes in the axial center of the output shaft and the center of the cam member and fitting pin members into these through holes. That is, by fitting the pin members into the through holes in the axial center of the output shaft and the center of the cam member, the axial center of the output member and the center of the cam member cannot become misaligned, and the cam member cannot come into contact with one of the braking members (first braking member). As a result, the braking member no longer presses against the stationary member, allowing the output member to rotate.

[0025] The release mechanism may include a biasing member interposed between the cam member and the output member to bias the cam member and the output member in a direction separating them from each other, and a guide portion that limits the relative rotation between the cam member and the output member when the cam member and the output member are close to each other against the biasing member, and by limiting the relative rotation between the cam member and the output member, the reverse input blocking state is released.

[0026] With this configuration, when the cam member and the output member are brought closer together against the biasing member, the guide portion restricts the relative rotation between the cam member and the output member, which is equivalent to the state in which the pin member is fitted into the axial center of the output shaft and the through-hole in the center of the cam member, thereby releasing the reverse input blocking state.

[0027] The device may also include a screw member attached to the stationary member, and by screwing the screw member forward, the screw member presses the input member and the cam member toward the output member, and the guide portion restricts the relative rotation between the cam member and the output member, thereby releasing the reverse input blocking state.

[0028] In this case, by threading the screw member, the screw member can press the input member and the cam member toward the output member. As a result, when the cam member and the output member are brought closer together, the guide portion restricts the relative rotation between the cam member and the output member. This creates a state similar to when the pin member is inserted into the axial center of the output shaft and the through-hole in the center of the cam member, thereby releasing the reverse input blocking state.

[0029] It is preferable that an intermediate portion between the first contact portion and the second contact portion is disposed at a position radially spaced from the rotation center of the input shaft of the input member, and that the first contact portion and the second contact portion of the cam member have different distances to the rotation center of the input shaft of the input member, or that the first contact portion is disposed on the opposite side of the second contact portion with respect to a perpendicular line that passes through the rotation center of the cam member and is perpendicular to the pressed surface of the brake member.Furthermore, it is preferable that the first braking member and the second braking member swing around one radial end side, and that the swing center is disposed on the opposite side of the intermediate portion between the first contact portion and the second contact portion with respect to a perpendicular line that passes through the rotation center of the input shaft and is perpendicular to the pressed surface of the brake member.Furthermore, it is preferable that a connecting portion between the arm portion of the output member and the cam member is disposed radially outward from the rotation center of the cam member. Here, the intermediate portion between the first contact portion and the second contact portion refers to the midpoint of the line segment connecting the first contact portion and the second contact portion.

[0030] Therefore, it is possible to increase the frictional force at the contact portion (contact surface) between the stationary member and one of the braking members, thereby increasing the braking torque in a self-amplifying manner. A force for interrupting the transmission of torque to the input member can be effectively generated. In addition, by arranging the connecting portion between the arm portion of the output member and the cam member radially outward from the center of the protrusion of the cam member, the rotation angle of the output member at the position where rotation of the cam member is restricted becomes smaller, and backlash of the output member is reduced, enabling stable interruption of torque. [Effects of the Invention]

[0031] In the present invention, the backlash of the output member can be reduced. Moreover, the load acting on the cam member can be reduced, and the strength of the clutch can be increased. Furthermore, the output member can be rotated manually during a power outage or other such event. In other words, the output member can be rotated in an emergency or abnormal situation. [Brief explanation of the drawings]

[0032] [Figure 1] FIG. 2 is a simplified exploded perspective view of the reverse input cutoff clutch according to the present invention. [Figure 2] FIG. 10 is a vertical cross-sectional view showing a state in which the pin member is not inserted. [Figure 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. [Figure 4] FIG. 10 is a vertical cross-sectional view showing a state in which the pin member is fitted. [Figure 5] FIG. 5 is a cross-sectional view taken along line BB in FIG. 4. [Figure 6] FIG. 2 is a simplified diagram viewed from the output side in a state where torque is input to an input member. [Figure 7] FIG. 10 is a simplified diagram viewed from the output side in a state where torque is reversely input to the output member. [Figure 8] FIG. 10 is a simplified diagram viewed from the input side in a state where torque is reversely input to the output member. [Figure 9] 2A and 2B show a state in which torque is reversely input to the output member of the reverse input cutoff clutch shown in FIG. 1, where FIG. 2A is a cross-sectional view and FIG. 2B is an enlarged cross-sectional view of a main portion. [Figure 10] 10 is a simplified diagram viewed from the output side in a state where reverse input interruption is released and torque is reversely input to the output member; FIG. [Figure 11] 10 is a simplified diagram viewed from the input side in a state in which reverse input interruption is released and torque is reversely input to the output member; FIG. [Figure 12] FIG. 10 is a simplified exploded perspective view showing a first modified example of the reverse input cutoff clutch. [Figure 13] FIG. 10 is a simplified diagram viewed from the input side in a state where torque is reversely input to the output member. [Figure 14] FIG. 2 is a simplified diagram viewed from the output side in a state where torque is input to an input member. [Figure 15] FIG. 10 is a simplified cross-sectional view showing a second modified example of the reverse input cutoff clutch. [Figure 16] FIG. 16 is a vertical cross-sectional view of the reverse input cutoff clutch shown in FIG. [Figure 17] FIG. 17 is a cross-sectional view taken along line DD in FIG. 16. [Figure 18] 16 is a vertical cross-sectional view of the reverse input cutoff clutch shown in FIG. 15 in a state where reverse input cutoff is released. FIG. [Figure 19] 19 is a cross-sectional view taken along the line EE in FIG. 18. [Figure 20] FIG. 10 is a simplified cross-sectional view showing a third modified example of the reverse input cutoff clutch. [Figure 21] FIG. 21 is a vertical cross-sectional view of the reverse input cutoff clutch shown in FIG. 20. [Figure 22] 22 is a cross-sectional view taken along the line FF in FIG. 21. [Figure 23] 22 is a vertical cross-sectional view of the reverse input cutoff clutch shown in FIG. 21 in a state where reverse input cutoff is released. FIG. [Figure 24] 24 is a cross-sectional view taken along line GG in FIG. 23. [Figure 25] FIG. 10 is a simplified cross-sectional view showing a fourth modified example of the reverse input cutoff clutch. [Figure 26] FIG. 26 is a vertical cross-sectional view of the reverse input cutoff clutch shown in FIG. 25. [Figure 27] 27 is a cross-sectional view taken along line HH in FIG. 26. [Figure 28] 1 is a simplified diagram showing a conventional reverse input cutoff clutch in a state where a reverse torque is input to an output member. [Figure 29] FIG. 29 is an enlarged view of a main part of FIG. 28. DETAILED DESCRIPTION OF THE INVENTION

[0033] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 25. FIG. 1 shows a simplified perspective view of a reverse input cutoff clutch according to the present invention, FIG. 2 shows a longitudinal cross-sectional view of the reverse input cutoff clutch, FIG. 3 shows a cross-sectional view taken along line AA in FIG. 2, FIG. 4 shows a longitudinal cross-sectional view of the reverse input cutoff clutch with a pin member inserted, FIG. 5 shows a cross-sectional view taken along line BB in FIG. 4, and FIG. 6 is a simplified view of the reverse input cutoff clutch as seen from the output side. The reverse input cutoff clutch is a reverse input cutoff clutch having an input member 21 to which torque is input, an output member 22 to which torque is output, a pair of first and second braking members 23A and 23B capable of reciprocating radially, and a stationary member 24 disposed radially outward so as to cover the first and second braking members 23A and 23B. Here, the radial direction refers to a direction perpendicular to the rotation axis. The device also includes a separating mechanism M1 that moves the pair of first and second braking members 23A, 23B in a direction radially approaching each other when torque is input to the input member 21, thereby moving the first and second braking members 23A, 23B in a direction away from the stationary member 24, and a transmission mechanism M2 that transmits the torque input to the input member 21 to the output member when the first and second braking members 23, 23 are away from the stationary member 24.

[0034] In addition, this reverse input disconnection clutch is provided with a release mechanism K that releases the reverse input disconnection state, i.e., the transmission of torque from the output member 22 to the input member 21, and in this case, a pin member 55 is provided as the release mechanism K.

[0035] The input member 21 includes an input shaft portion 21a and a main body portion 21b connected to one end surface of the input shaft portion 21a. The main body portion 21b has a disk portion 27 and a pair of bulging portions 28A, 28B provided on the opposite side of the disk portion 27 from the input shaft portion. The bulging portions 28A, 28B are provided at positions 180° opposite each other with respect to the center of the disk portion 27. The bulging portions 28A, 28B are provided on the outer peripheral edge side of the disk portion 27, and their inner diameter portions are flat surfaces 29a, 29a that face each other, and their outer diameter surfaces are arcuate surfaces 29b, 29b that are integrated with the outer peripheral edge of the disk portion 27.

[0036] The output member 22 has an output shaft portion 22a and an arm portion 22b extending radially outward from the axial end (the end on the input member side) of the output shaft portion 22a, and is connected to a cam member 30. Here, the axial direction refers to the direction along the central axis of the output shaft portion 22a, i.e., the direction of the center line of rotation when an object rotates. The cam member 30 has a flat body portion 30a extending radially and a protrusion portion 30b provided on the end surface of the body portion 30a facing the input member. The protrusion portion 30b has a rectangular parallelepiped shape and is not provided on one radially outer side of the body portion 30a. The arm portion 22b of the output member 22 is connected to the cam body portion 30a of the cam member 30 via a support shaft portion 31, which constitutes a connecting portion, with the arm portion 22b of the output member 22 and the back side (the side opposite the input member side) of the cam body portion 30a of the cam member 30 overlapping each other. In this case, the output member 22 and the cam member 30 are pivotally connected via the support shaft portion 31, and the output member 22 and the cam member 30 swing around the support shaft portion 31. Through holes 31a, 31a are provided in the arm portion 22b and the cam main body portion 30a, and the support shaft portion 31 is fitted into these through holes 31a, 31a.

[0037] The output shaft portion 22a of the output member 22 and the cam member 30 are provided with axial holes 56, 57, respectively, and a pin member 55 constituting the release mechanism K is fitted into the axial holes 56, 57 as shown in FIGS.

[0038] The braking members 23A, 23B each have a flat plate-shaped main body 32 and a protrusion 33 protruding inward from one longitudinal end of the main body 32. The braking members 23A, 23B are pivotally connected via a support shaft 34 that forms the center of oscillation while overlapping the protrusion 33, and the braking members 23A, 23B oscillate around the support shaft 34. When the braking members 23A, 23B are connected, a gap S1 (see FIG. 8) is provided between the main bodies 32, and the protrusion 30b of the cam member 30 is fitted into this gap S1. Each protrusion 33 is provided with a through hole 33a, into which the support shaft 34 is fitted.

[0039] Furthermore, the braking members 23A, 23B are interposed between the bulging portions 28A, 28B of the input member 21. When torque is input to the input member 21 in the direction of arrow A1 shown in FIG. 5, the input shaft portion 21a of the input member 21 rotates in the direction of arrow A1 about its axis, and the pair of bulging portions 28A, 28B also rotate about the axis of the input shaft portion 21a. As a result, one end (the lower end in the illustrated example) of the flat surface 29a on the inner diameter of the first bulging portion 28A presses the braking member 23A inward, and the other end (the upper end in the illustrated example) of the flat surface 29a on the inner diameter of the second bulging portion 28B presses the braking member 23B inward. As a result, the braking members 23A, 23B come relatively close to each other.

[0040] 1 and 2, the stationary member 24 is composed of a first frame 35 and a second frame 36. The first frame 35 is composed of a short cylindrical peripheral wall portion 35b, and an axial hole 37 is formed in the disk portion 35a. The second frame 36 is also disk-shaped, and in this case, an axial hole 38 is also formed. A circumferential cutout portion 36a is formed in the outer end of the inner surface of the second frame 36, and the first frame 35 and the second frame 36 are integrated with each other in a state where the end of the peripheral wall portion 35b of the first frame 35 is fitted into this circumferential cutout portion 36a. Therefore, the stationary member 24 has an accommodation chamber S (see FIG. 2, etc.) in which the braking members 23, 23, the cam member 30, etc. are accommodated.

[0041] With the arm portion 22b of the output member 22 housed in the housing chamber S of the stationary member 24, the output shaft portion 22a is supported in the shaft hole 37 via a bearing 40, and with the main body portion 21b of the input member 21 housed in the housing chamber S, the input shaft portion 21a is supported in the shaft hole 38 via a bearing 41. Also, as shown in FIG. 2, the input shaft portion 21a of the input member 21 and the output shaft portion 22a of the output member 22 are arranged on the same axis.

[0042] The longitudinal outer end faces of the braking members 23A, 23B are formed as arcuate contact surfaces 42, 42, and the curvature of the contact surface 42 is smaller than the curvature of the inner diameter surface 43 of the peripheral wall portion 35b of the stationary member 24.

[0043] Next, the operation of the reverse input cutoff clutch configured as described above will be described. The operation will be described when the pin member 55 is not inserted into the axial holes 56, 57. When torque is input to the input member 21, that is, when a rotational force is applied in the direction of arrow A1 as shown in FIG. 6, the braking members 23A, 23B move closer to each other in the radial direction, as described above. This movement causes the abutment surface 42 of the braking member 23 to move away from the abutted surface 43a of the stationary member 24. In this spaced-apart state, the input member 21 rotates around its axis (the axis of the input shaft portion 21a). This rotation causes the braking members 23, 23 to rotate. Furthermore, the cam member 30 sandwiched between the braking members 23, 23 rotates around the axis of the input member 21. When the cam member 30 rotates, the output member 22 connected to the cam member 30 rotates around the axis of the output shaft portion 22a. That is, when torque is input to the input member 21, the torque is transmitted to the output member 22, and the output shaft portion 22a of the output member 22 rotates.

[0044] For this reason, the present reverse input disconnecting clutch has a separation movement mechanism M1 that moves the first and second braking members 23A, 23B in a direction separating them from the stationary member 24, and the separation movement mechanism M1 can be configured by a pair of bulging portions 28A, 28B of the disk portion 27.

[0045] Furthermore, this reverse input cutoff clutch is provided with a transmission mechanism M2 that transmits torque input to the input member 21 to the output member 22 when the first and second braking members 23, 23 are separated from the stationary member 24, and this transmission mechanism M2 can be composed of the first and second braking members 23, 23, a cam member 30, etc.

[0046] However, if torque is input in reverse to the output member 22, the torque is not transmitted to the input member 21. In other words, if torque is input (reverse input) to the output member 22, the output member 22 rotates. When the output member 22 rotates, the support shaft 31 connecting the cam member 30 and the output member 22 rotates around the axis of the output shaft 22a of the output member 22. Therefore, the cam member 30 rotates around the axis of the output shaft 22a of the output member 22, as shown in FIG. 7. Therefore, the cam member 30 presses each of the pair of braking members 23, 23 that are connected by the support shaft 34 so as to be rotatable relative to each other, toward the stationary member 24. In other words, as shown in FIGS. 8 and 9(a), the protrusion 30b interposed between the pair of braking members 23, 23 rotates around the axis O. The axis O is the axis of the input shaft portion 21a of the input member 21 and the axis of the output shaft portion 22b of the output member 22, which are coaxially aligned.

[0047] When the protrusion 30b rotates around the axis O, an edge X1 on the support shaft side of the side surface of the protrusion 30b facing the first braking member presses the first braking member 23A toward the stationary member 24, and an edge X2 on the anti-support shaft side of the side surface of the protrusion 30b facing the second braking member presses the second braking member 23B toward the stationary member 24. As a result, torque transmission is interrupted by a frictional force generated between the abutting surface 42 of the braking member 23 and the abutted surface 43a of the stationary member 24. Here, the midpoint position of the line segment connecting the edge X1 (first contact portion) and the edge X2 (second contact portion) is defined as an intermediate portion X3.

[0048] However, in order to block and stop the reverse input, regarding the relationship of the forces acting on one of the braking members 23 (in this case, the first braking member 23A), if the reverse input torque is T and the braking torque is T', it is necessary that T < T'. In this case, among the respective contact portions X1, X2 between the cam member 30 and the pair of braking members 23A, 23B, the distance from the contact portion X1 close to the rotation center O to the rotation center is r (see FIGS. 9(a) and (b)), the distance from the contact portion X2 far from the rotation center O to the rotation center is r', the distance from the rotation center O to the braking member 23 and the stationary member 24 is R, the friction coefficient between the contact portions X1, X2 of the cam member 30 and the braking member 23 is μ, and the friction coefficient between the contact portion C of the braking member 23 and the stationary member 24 is μ'. In this case, a tangential force Ft orthogonal to the straight line connecting the contact portion X1 and the rotation center O acts on the contact portion X1, and among the angles formed by the direction in which the tangential force Ft acts and the braking member pressed surface 23a, the acute angle side angle is β (see FIG. (b)). The braking member pressed surface 23a is the surface of the braking member 23 that faces the protrusion 30b of the cam member 30 and is pressed by the protrusion 30b. Let the angle formed by the tangent Y at the contact portion C between the braking member 23 and the stationary member 24 and the perpendicular line P passing through the rotation center O and orthogonal to the contact surface of the braking member pressed surface 23a be α. Therefore, in order to satisfy the above-mentioned T < T', it is necessary to satisfy the formula shown in Equation 2 below.

Equation

[0049] Meanwhile, one of the brake members 23A, which comes into contact with the cam member 30 at X1, is pressed against the stationary member 24 by the cam member 30, satisfying the reverse input blocking condition of Equation 2, and the brake member 23A comes to a standstill. The other brake member 23B, which comes into contact with the cam member 30 at X2, which is farther from the support shaft 31 than X1, is pressed against the stationary member 24 by the cam member 30. However, since r' is large and does not satisfy the reverse input blocking condition of Equation 2, a rotational torque acts in the same direction as the reverse input torque acting on the output member 22, and this torque is transmitted to the support shaft 34. The cam member 30 presses the brake members 23A and 23B against the stationary member 24 between the brake members 23A and 23B, restricting their movement toward each other. Therefore, the movement of the pair of brake members 23A and 23B away from the stationary member 24 is restricted. Furthermore, frictional force acts on braking member 23A in the direction opposite to the rotational direction of output member 22, causing it to rotate around support shaft 34 in a direction away from the other braking member 23B. This rotation increases the frictional force on the contact surface between stationary member 24 and braking member 23A, causing a self-amplifying increase in braking torque. Therefore, braking members 23A and 23B come to a standstill, restricting the rotation of cam member 30 and output member 22.

[0050] It is desirable to increase the distance between the contact portions of the cam member 30 and the pair of braking members 23A, 23B. Increasing the distance reduces the angle of rotation of the cam member 30 (specifically, the protrusion 30b of the cam member 30) sandwiched between the braking members 23A, 23B within the gap S1, thereby reducing backlash of the output member 22. Furthermore, the load acting on the cam member 30 is reduced, thereby increasing the strength of the clutch. It is also desirable to position the support shaft 31 connecting the cam member 30 and the output member 22 radially outward. Positioning the support shaft 31 radially outward reduces the rotation angle of the output member 22 at the position where the rotation of the cam member 30 is restricted, thereby reducing backlash of the output member 22. Furthermore, the load acting on the support shaft 31 is reduced, thereby increasing the strength of the clutch. In addition, in the prior art, the engagement portion of the output member and the contact portion of the pair of engaging members are symmetrical, and the length of r is limited because it significantly affects the strength and backlash of the output member. However, in the clutch according to the present invention, the distance between the contact portions X1 and X2 between the cam member 30 and the pair of braking members 23A and 23B can be increased even if r is reduced, so there is a high degree of freedom in designing r. Therefore, there is no need to increase R to satisfy the relationship in Equation 2, and the outer diameter size can be reduced.

[0051] As described above, according to the reverse input cutoff clutch of the present invention, when torque is input to the input member 21, the pair of braking members 23A, 23B separate from the stationary member 24. In this separated state, the torque input to the input member 21 is transmitted to the output member 22, causing the output member 22 to rotate. Furthermore, when torque is input to the output member 22, the cam member 30 rotates, causing the first and second braking members 23A, 23B to move relatively apart. This presses the first and second braking members 23A, 23B against the stationary member 24, thereby cutting off the transmission of torque from the output member 22 to the input member 21. The relative separation of the first and second braking members 23A, 23B is achieved by the rotation of the cam member 30 interposed between the first braking member 23A and the second braking member 23B. At this time, the cam member 30 restricts the first and second braking members 23A, 23B from approaching each other, effectively preventing the pair of braking members 23A, 23B from moving away from the stationary member 24. Furthermore, when the first and second braking members 23A, 23B move away from each other, the end of the cam member 30 on the first braking member side comes into contact with the first braking member 23A, and the end on the second braking member side comes into contact with the second braking member 23B, and if the end on the first braking member side rotates counterclockwise, the end on the second braking member side also rotates counterclockwise. In this case, the end on the first braking member side presses the side of the first braking member opposite the second braking member, and the end on the second braking member side presses the side of the second braking member opposite the first braking member. Incidentally, the distance between the first contact portion X1 on the cam member side that contacts the first braking member 23A and the second contact portion X2 on the cam member side that contacts the second braking member 23B can be set relatively long, and by setting it long, the angle of rotation of the cam member 30 between the first and second braking members 23A and 23B is reduced, thereby reducing backlash of the output member 22. Moreover, the load acting on the cam member 30 can be reduced, thereby increasing the strength of the clutch.

[0052] Therefore, in the present invention, it is possible to reduce backlash in the output member 22. Moreover, it is possible to reduce the load acting on the cam member 30, thereby increasing the strength of the clutch.

[0053] However, when torque is reversely input to the output member 22 with the pin member 55 fitted in the axial holes 56, 57, the output member 22 rotates about its rotational axis O. Accompanying this rotation, the cam member 30, whose relative rotation with the output member 22 is restricted, rotates synchronously with the output member 22. In this case, as shown in FIGS. 10 and 11 , the cam member 30 does not come into contact with the brake member 23A, but only with the brake member 23B. Therefore, a gap is formed between the brake member 23A and the cam member 30, and movement of the brake member 23A toward the brake member 23B is not restricted. In this case, the brake member 23A does not satisfy the reverse input blocking condition of Mathematical Expression 2 described above, and therefore a rotational torque acts on the output member 22 in the same direction as the reverse input torque acting on the output member 22, and the torque is transmitted to the support shaft portion 34. Furthermore, because braking member 23A is movable around support shaft portion 34 in a direction away from braking member 23B, a reaction force from the contact portion with stationary member 24 causes braking member 23A to move away from stationary member 24 and rotate synchronously with braking member 23A and cam member 30. Braking members 23A and 23B come into contact with input member 21, causing braking members 23A and 23B and input member 21 to rotate synchronously. As a result, reverse input blocking is released, and output member 22 and input member 21 rotate synchronously. Furthermore, when torque is input to input member 21, input member 21 and output member 22 rotate synchronously as in the operation shown in FIG. 6.

[0054] Therefore, by providing a release mechanism K that releases the interruption of the transmission of torque from the output member 22 to the input member 21, the brake can be released in the event of a power outage, etc., and the output member 22 can be rotated manually. In addition, in the configuration shown in Fig. 1, the relative rotation of the output member 22 and the cam member 30 can be restricted simply by fitting the pin member 55 into the axial holes 56, 57 of the output member 22 and the cam member 30, and this makes it possible to rotate the output member 22 manually, which has the advantage of not being a complicated mechanism.

[0055] In the reverse input cutoff clutch shown in Fig. 1 etc., the braking members 23A, 23B are connected by a support shaft portion 34, but the reverse input cutoff clutch shown in Figs. 12 to 14 does not use a support shaft portion 34. The protrusions 33, 33 protruding inward from one end in the longitudinal direction of the main body portions 32, 32 of the braking member 23 are cylindrical protrusions 33A, 33B whose opposing surfaces are cylindrical surfaces.

[0056] In the reverse input cutoff clutch shown in FIG. 12, when torque is reversely input to the output member 22, the output member 22 rotates in the same manner as in the reverse input cutoff clutch shown in FIG. 1, etc., and as shown in FIG. 13, the support shaft 31, which rotatably connects the output member 22 and the cam member 30, rotates (revolves). The rotation (revolution) of the support shaft 31 causes the cam member 30 to press each of the pair of braking members 23A, 23B toward the stationary member 24. The braking member 23A, which comes into contact with the cam member 30 at X1, is stationary because the relationship of reverse input torque T<braking torque T'. The braking member 23B, which has the relationship of reverse input torque T>braking torque T', rotates around the rotation axis O, and the cylindrical protrusions 33A, 33B of the braking member 23A come into contact with each other. A force acts on the cylindrical protrusion 33A of the braking member 23A in the same rotational direction as the output member 22. The cam member 30 presses the brake members 23A, 23B against the stationary member 24, restricting the movement of the brake members 23A, 23B toward each other. Therefore, the movement of the pair of brake members 23A, 23B away from the stationary member 24 is restricted. Furthermore, frictional force acts on the brake member 23A in the direction opposite to the rotational direction of the output member 22, causing the brake member 23A to rotate away from the brake member 23B around the contact points of the cylindrical protrusions 33A, 33B as a fulcrum. This rotation increases the frictional force at the contact surfaces between the stationary member 24 and the brake member 23A, resulting in a self-amplifying increase in braking torque. Therefore, the brake members 23A, 23B are stationary, restricting the rotation of the cam member 30 and the output member 22.

[0057] FIG. 14 shows the operation when torque is input to the input member 21. When torque is input to the input member 21, the input member 21 comes into contact with each of the pair of braking members 23A, 23B, pressing the pair of braking members 23 toward each other. The pair of braking members 23 come into contact with each other's cylindrical protrusions 33A, 33B, and rotate around the centers of the cylindrical protrusions 33A, 33B as fulcrums in a direction in which the braking members 23 approach each other. This rotation causes the braking members 23 to move away from the stationary member 24, and the pair of braking members 23 rotate with the cam member 30 sandwiched between them. The rotation of the cam member 30 rotates the output member 22, which is connected to the cam member 30 by the support shaft portion 31. Therefore, the input member 21 and the output member 22 rotate synchronously.

[0058] 1, and the reverse input cutoff clutch shown in FIG. 12 etc. has the same components as those shown in FIG. 1 etc., with the same reference numerals used to designate the same components, and their description will be omitted. Therefore, the reverse input cutoff clutch shown in FIG. 12 also achieves the same effects as the reverse input cutoff clutch shown in FIG. 1. Moreover, the reverse input cutoff clutch shown in FIG. 12 can reduce the number of parts compared to the reverse input cutoff clutch shown in FIG. 1, and can also form a load transmission path between the braking members by contact between the cylindrical protrusions, thereby improving strength.

[0059] Next, the reverse input cutoff clutch shown in Figures 15 to 19 includes a release mechanism K, such as a biasing member 60 made of a coil spring. Specifically, the release mechanism K in this case includes a biasing member 60 interposed between the output member 22 and the cam member 30, and a guide portion 63 that limits relative rotation between the cam member 30 and the output member 22 when the cam member 30 and the output member 22 approach each other against the biasing member. A simplified cross-sectional view showing a second modified example of the reverse input cutoff clutch is shown in Figure 16. Figure 17 is a cross-sectional view taken along line DD in Figure 15. Figure 18 is a cross-sectional view of the reverse input cutoff clutch shown in Figure 15 in a state where reverse input cutoff is released, and Figure 19 is a cross-sectional view taken along line EE in Figure 18.

[0060] A recessed portion 61 is provided on the end face 22a1 of the output shaft portion 22a of the output member 22 on the cam member 30 side, and a recessed portion 62 is provided on the end face 30a1 of the cam member 30 corresponding to this recessed portion 61, and the ends of the urging member 60 are fitted into each recessed portion 61, 62, respectively.

[0061] Further, the guide portion 63 is composed of plate-like pieces 63A, 63B provided on both side ends of the arm portion 22b of the output member 22. In this case, the distance between the plate-like pieces 63A, 63B is the same as the width dimension of the cam main body portion 30a of the cam member 30. Here, "similar" means that when the output member 22 approaches the cam member 30, the output member 22 and the cam member 30 are allowed to come into contact with each other as shown in FIG. 18, and when the output member 22 and the cam member 30 are in contact with each other, the cam main body portion 30a of the cam member 30 is interposed between the plate-like pieces 63A, 63B, and the cam member 30 cannot swing relative to the output member 22. The guide portion 63 may be provided on the cam member 30 instead of the output member 22.

[0062] 16, the elastic force of biasing member 60 causes guide portion 63 and output member 22 to be separated from each other, and cam main body portion 30a of cam member 30 is not interposed between plate-like piece portions 63A and 63B, allowing cam member 30 to swing relative to output member 22. Therefore, in this state, the reverse input blocking state is not released, and when torque is reversely input to output member 22, the torque is not transmitted to input member 21.

[0063] Furthermore, from the state shown in Figure 16, as shown in Figure 18, if the input member 22 is pushed toward the cam member 30 against the elastic force of the biasing member 60, bringing the output member 22 and cam member 30 into contact with each other and the cam main body portion 30a of the cam member 30 into a state where it is interposed between the plate-shaped piece portions 63A and 63B, the cam member 30 will not be able to swing relative to the output member 22.

[0064] In this way, if the cam member 30 cannot swing relative to the output member 22, as shown in Figure 11, when torque is input in reverse to the output member 22, the cam member 30 will not press the first braking member 23A, and the braking members 23A and 23B will not be pressed against the stationary member 24, and the torque will be transmitted to the input member 21.

[0065] 20 to 24, unlike the reverse input cutoff clutches shown in FIGS. 15 to 19, a screw member 65 can be screwed into the stationary member 24. That is, a screw hole 66 is provided in the second frame 36 of the stationary member 24, and the screw member 65 is screwed into this screw hole 66 from the outside into the stationary member 24. In the illustrated example, a hexagon socket set screw is used as the screw member 65. FIG. 20 is a simplified cross-sectional view showing a third modified example of the reverse input cutoff clutch, FIG. 21 is a longitudinal cross-sectional view of the reverse input cutoff clutch shown in FIG. 20, FIG. 22 is a cross-sectional view taken along line FF in FIG. 21, FIG. 23 is a longitudinal cross-sectional view of the reverse input cutoff clutch shown in FIG. 21 in a state in which reverse input cutoff is released, and FIG. 24 is a cross-sectional view taken along line GG in FIG. 23.

[0066] 21, when tip surface 65a of screw member 65 has not entered accommodation chamber S, it is not pressing input member 21 against output member 22. Therefore, the elastic force of biasing member 60 causes output member 22 to be spaced apart from cam member 30. In other words, cam main body 30a of cam member 30 is not interposed between plate-like piece portions 63A, 63B, and cam member 30 is able to swing relative to output member 22. When torque is input in reverse to output member 22, torque transmission to input member 21 is interrupted.

[0067] However, as shown in Fig. 23, if screw member 65 is threaded forward and tip surface 65a of screw member 65 presses input member 21 toward output member 22, arm portion 22b of output member 22 is pressed via cam member 30 until it contacts the inner end surface of first member 35 of stationary member 24. In this state, cam main body portion 30a of cam member 30 is interposed between plate-like piece portions 63A and 63B, and cam member 30 cannot swing relative to output member 22. As a result, if cam member 30 cannot swing, when torque is reversely input to output member 22 as shown in Fig. 11, cam member 30 does not press first braking member 23A, braking members 23A and 23B do not come into pressure contact with stationary member 24, and torque is transmitted to input member 21. That is, the relative rotation between the output member 22 and the cam member 30 is restricted, and the transmission of torque from the output member 22 to the input member 21 is released from the interruption.

[0068] In the illustrated example, the support shaft portion 31 protrudes from the arm portion 22b of the output member 22 toward the anti-input side, so a recess 70 is provided in the disk portion 35a of the first member 35 of the stationary member 24 at a portion corresponding to the support shaft portion, and as shown in Figure 23, when the input member 21 is pressed toward the output member 22 by the screw member 65, the protruding portion of the support shaft portion 31 is fitted into the recess 70.

[0069] In the reverse input cut-off clutch shown in Figures 25 to 27, the braking members 23A, 23B are urged by the elastic member 50 in a direction in which they move relatively apart along the radial direction, and in a free state, the abutment surfaces 42, 42 of the braking members 23A, 23B abut against the abutted surface 43a of the inner diameter surface 43 of the peripheral wall portion 35b of the stationary member 24.

[0070] Specifically, the elastic member 50 is made of a coil spring, and recessed portions 51, 51 are provided on the corresponding surfaces 23A1, 23B1 of the braking members 23A, 23B that face each other, and the ends of the elastic member 50 fit into the recessed portions 51, 51. As a result, the elastic member 50 is elastically biased in a direction that moves it away from the braking members 23A, 23B.

[0071] With this configuration, it is possible to synchronize the attitudes of the braking members 23, 23 and stabilize the attitude of each braking member 23, thereby enabling accurate radial movement of each braking member 23. Furthermore, as will be described later, except when rotational torque is input to the input member 21, it is possible to keep the contact surface 42 of each braking member 23 pressed against the contacted surface 43a.

[0072] Although the above describes an embodiment of the present invention, various modifications are possible without being limited to the above embodiment. For example, the contact portions X1 and X2 formed on the protrusion 30b of the cam member 30 may be rounded or obtuse-angled. Furthermore, the dimensions r, r', and R, and the friction coefficients μ and μ' may be set arbitrarily as long as they satisfy the formula (2) described in the embodiment. Although the reverse input disconnecting clutches shown in FIGS. 12 to 24 do not include an elastic member 50, it is preferable to include an elastic member 50. The elastic member 50 may be a spring made of metal or other material (such as a coil spring, leaf spring, or disc spring), rubber, or resin. The position of the elastic member 50 is not limited to the position shown in FIGS. 25 to 27, and may be any position capable of biasing the braking members 23A and 23B in a radially spaced apart direction.

[0073] Furthermore, the protrusion 30b of the cam member 30 may be configured as a pair of spaced apart protrusions. The protrusion closer to the support shaft 31 is designated as the first protrusion, and the protrusion farther from the support shaft 31 is designated as the second protrusion. The edge of the first protrusion facing the first braking member is designated as the first contact portion X1, and the edge of the second protrusion facing the first braking member is designated as the second contact portion X2. This configuration provides a space between the first protrusion and the second protrusion, which has the advantage of reducing the volume compared to the protrusion 30b shown in FIG. 1 and thereby reducing the weight of the cam member 30. Note that this reverse input disconnect clutch is symmetrical when viewed from both the input side and the output side. When torque is input to the input member 21, it operates in the same manner whether the torque is clockwise or counterclockwise. When torque is input reversely to the output member 22, it operates in the same manner whether the torque is clockwise or counterclockwise. [Explanation of symbols]

[0074] 21 Input member 21a Input shaft 22 Output member 22a Output shaft 22b Arm part 23, 23A, 23B braking members 23a Braking member pressed surface 24 Stationary Members M1 Separation movement mechanism M2 transmission mechanism 30 Cam member 30a Cam body 30b Protrusion (convex part) 30c convex part 30d convex part 31 Support shaft part (connection part) 33, 33A, 33B protrusion 34 Support shaft part K release mechanism M1 Separation movement mechanism M2 transmission mechanism O Rotation axis X1, X2 Contact area (edge)

Claims

1. A reverse input cutoff clutch having an input member to which torque is input, an output member to which torque is output, a first braking member and a second braking member capable of reciprocating in a radial direction, and a stationary member disposed radially outward of the first braking member and the second braking member, a separating movement mechanism that, when torque is input to the input member, moves the first braking member and the second braking member in a direction in which they approach each other in the radial direction, and moves the first braking member and the second braking member in a direction in which they move away from the stationary member; a transmission mechanism that transmits torque input to the input member to the output member in a state in which the first braking member and the second braking member are spaced apart from the stationary member, A reverse input cut-off clutch characterized in that a cam member is interposed between the first brake member and the second brake member, and when torque is reverse input to the output member, the rotational motion is transmitted to the cam member, causing the first brake member and the second brake member to move in a direction separating them radially from each other, and the first brake member and the second brake member are pressed against the stationary member, thereby cutting off the transmission of torque from the output member to the input member, and further comprising a release mechanism that restrains the relative rotation of the output member and the cam member and releases the cut-off of the transmission of torque from the output member to the input member.

2. 2. The reverse input cutoff clutch according to claim 1, wherein the output member has an output shaft portion disposed coaxially with the axis of the input shaft portion of the input member, and an arm portion extending radially from the output shaft portion, and the cam member has a cam main body portion extending radially and having one radial end connected to a radially outer diameter side end of the arm portion of the output member, and a protrusion portion provided on the cam main body and disposed between the first braking member and the second braking member, and when torque is reverse input to the output member, the connecting portion of the arm portion swings around the output shaft portion of the output member, and the pair of first contact portion and second contact portion of the protrusion portion press against braking member pressed surfaces of the first braking member and the second braking member, respectively, and move in directions radially apart from each other.

3. 2. The reverse input cutoff clutch according to claim 1, wherein a through hole is provided in the axial center of the output shaft portion and the center of the cam member, and the release mechanism is configured by inserting a pin member into this through hole.

4. 3. The reverse input disconnection clutch according to claim 2, wherein the release mechanism comprises a biasing member interposed between the cam member and the output member to bias the cam member and the output member in directions separating them from each other, and a guide portion that limits relative rotation between the cam member and the output member when the cam member and the output member are close to each other against the biasing member, and by limiting the relative rotation between the cam member and the output member, the reverse input disconnection clutch is released from the reverse input disconnection state.

5. 5. The reverse input disconnection clutch according to claim 4, further comprising a screw member attached to the stationary member, wherein by threading the screw member, the screw member presses the input member and the cam member toward the output member, and the guide portion limits the relative rotation between the cam member and the output member, thereby releasing the reverse input disconnection state.

6. 3. The reverse input cutoff clutch according to claim 2, wherein an intermediate portion between the first contact portion and the second contact portion is disposed at a position radially spaced apart from the rotation center of the input shaft portion of the input member, and the first contact portion and the second contact portion of the cam member have a different distance to the rotation center of the input shaft portion of the input member.

7. 3. The reverse input cutoff clutch according to claim 2, wherein the first contact portion is disposed on the opposite side of the second contact portion with respect to a perpendicular line that passes through the rotation center of the cam member and is perpendicular to the pressed surface of the brake member.

8. 3. The reverse input cut-off clutch according to claim 2, wherein the first braking member and the second braking member swing about one radial end side, and the swing center is disposed on the opposite side of the intermediate portion of the first contact portion and the second contact portion with respect to a perpendicular line that passes through the rotation center of the input shaft and is perpendicular to the pressed surface of the braking member.

9. 3. The reverse input cutoff clutch according to claim 2, wherein a connecting portion between the arm portion of the output member and the cam member is disposed radially outward from a rotation center of the cam member.

10. 2. The reverse input disconnect clutch according to claim 1, wherein the input member and the output member are rotatably supported relative to the stationary member.

Images