Torque control clutch

Abstract

To easily manufacture a clutch device.SOLUTION: A clutch device 1 includes: an input member 2 including first and second input retaining parts 22A, 22B; an output member 3 including an output retaining part 32 whose cross-sectional shape orthogonal to a rotation axis line A is flat; an element 4 into which the first and second input retaining parts 22A, 22B are inserted so as to hold the rotation axis line A therebetween and which can hold the output retaining part 32; and a housing 5 including a housing inner peripheral surface 51d facing the element 4 and housing the element 4. The element 4 is an integrally molded article having: first and second element piece parts 40A, 40B each including an element pressing surface 41d and an input retaining hole 41H, and disposed so as to hold the output member 3 therebetween; and first and second element spring parts 43A, 43B disposed between the first element piece part 40A and the second element piece part 40B.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a torque control clutch.

Background Art

[0002] A torque control clutch has a function of allowing torque transmission from an input shaft to an output shaft and a function of restricting torque transmission from the output shaft to the input shaft. For example, Patent Document 1 discloses a reverse input blocking clutch having these functions.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The reverse input blocking clutch shown in Patent Document 1 has an input member, an output member, a pair of engaging elements, and a pair of springs. In particular, the configuration for restricting reverse input torque is formed by a pair of engaging elements and a pair of springs. Therefore, the manufacture of the reverse input blocking clutch requires a process of combining a plurality of parts. As a result, the manufacture of the reverse input blocking clutch was complicated.

[0005] An object of the present invention is to provide a torque control clutch that can be easily manufactured.

Means for Solving the Problems

[0006] A torque control clutch according to one embodiment of the present invention includes an input member provided so as to sandwich a rotation axis and including a pair of input latching portions extending along the rotation axis, an output member coaxial with the rotation axis, having a flat cross-sectional shape orthogonal to the rotation axis, and including an output latching portion extending along the rotation axis, an engaging member into which the pair of input latching portions are inserted so as to sandwich the rotation axis and which can sandwich the output latching portion between the inserted pair of input latching portions, and a pressed member including a pressed surface facing the engaging member and accommodating the engaging member. The engaging member includes an engaging member pressing surface facing the pressed surface and an input latching hole into which the input latching portion is inserted, and includes a first engaging member piece portion and a second engaging member piece portion disposed with the output member therebetween, and a portion continuous with the first engaging member piece portion and a portion continuous with the second engaging member piece portion, and is an integrally molded product having an engaging member elastic portion disposed between the first engaging member piece portion and the second engaging member piece portion.

[0007] The above torque control clutch allows transmission of torque from the input member to the output member and restricts reverse input of torque from the output member to the input member. The engaging member for achieving the function of transmitting torque and the function of restricting reverse input of torque is configured as an integral part including the first and second engaging member piece portion main bodies and the engaging member elastic portion. Therefore, the above torque control clutch can be easily manufactured because the number of parts is small.

[0008] In a torque control clutch of one form, the first engaging piece portion includes a first engaging piece portion main surface extending along the direction of the rotation axis, and a first engaging piece portion side surface extending along the direction of the rotation axis and facing a direction different from the first engaging piece portion main surface. The second engaging piece portion includes a second engaging piece portion main surface extending along the direction of the rotation axis and facing the first engaging piece portion main surface, and a second engaging piece portion side surface extending along the direction of the rotation axis and facing the same direction as the first engaging piece portion side surface. An output latching portion is disposed between the first engaging piece portion main surface and the second engaging piece portion main surface. The first end of the engaging piece elastic portion is continuous with the first engaging piece portion side surface, and the second end of the engaging piece elastic portion may be continuous with the second engaging piece portion side surface. Even with this configuration, a force in a direction to bring the first and second engaging piece portions closer to each other or a force in a direction to separate the first and second engaging piece portions from each other can be generated.

[0009] In a torque control clutch of one form, the first engaging piece portion includes a first engaging piece portion main surface extending along the direction of the rotation axis. The second engaging piece portion includes a second engaging piece portion main surface extending along the direction of the rotation axis and facing the first engaging piece portion main surface. An output latching portion is disposed between the first engaging piece portion main surface and the second engaging piece portion main surface. The first end of the engaging piece elastic portion is continuous with the first engaging piece portion main surface, and the second end of the engaging piece elastic portion may be continuous with the second engaging piece portion main surface. According to this configuration, a force in a direction to bring the first and second engaging piece portions closer to each other or a force in a direction to separate the first and second engaging piece portions from each other can be generated.

[0010] In a torque control clutch of one form, when the engaging piece is in a state of being accommodated in the pressed member, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is a first distance. When the engaging piece is not accommodated in the pressed member and the engaging piece elastic portion does not generate an elastic force, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is a second distance, and the first distance may be equal to the second distance.

[0011] In one form of the torque control clutch, when the engaging element is accommodated in the pressed member, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the first distance. When the engaging element is not accommodated in the pressed member and the engaging element elastic portion does not generate an elastic force, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the second distance. The first distance may be shorter than the second distance. According to this configuration, in a state where no torque is input from the input member, the engaging element pressing surface can be pressed against the pressed surface.

[0012] In one form of the torque control clutch, when the engaging element is accommodated in the pressed member, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the first distance. When the engaging element is not accommodated in the pressed member and the engaging element elastic portion does not generate an elastic force, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the second distance. The first distance may be longer than the second distance. According to this configuration, since the output locking portion is inserted between the first and second engaging element pieces to make the first distance longer than the second distance, the output locking portion can always be in contact with the first and second engaging element pieces.

[0013] The torque control clutch according to another aspect of the present invention includes an input member that is coaxial with the rotation axis, has a flat cross-sectional shape perpendicular to the rotation axis, and includes an input locking portion extending along the rotation axis, an output member that is coaxially arranged with the rotation axis and includes a pressed surface, and an engaging element that is coaxially arranged with the rotation axis and includes an engaging element locking surface facing the input locking portion and an engaging element pressing surface facing the pressed surface. The output member accommodates the engaging element. The engaging element includes an engaging element pressing surface and an engaging element locking surface respectively. The engaging element is an integrally molded product having a first engaging element piece and a second engaging element piece arranged with the input locking portion therebetween so that the engaging element locking surface faces the input locking portion, a portion continuous with the first engaging element piece, a portion continuous with the second engaging element piece, and an engaging element elastic portion arranged between the first engaging element piece and the second engaging element piece.

[0014] The above torque control clutch also allows the transmission of torque from the input member to the output member and restricts the reverse input of torque from the output member to the input member. The engaging element for achieving the functions of transmitting torque and restricting the reverse input of torque is configured as an integral part including a first and a second engaging element piece main body parts and an engaging element elastic part. Therefore, the above torque control clutch can be easily manufactured because the number of parts is small.

[0015] In another form of the torque control clutch, the first engaging element piece includes a first engaging element piece main surface extending along the direction of the rotation axis and a first engaging element piece side surface extending along the direction of the rotation axis and facing a direction different from that of the first engaging element piece main surface. The second engaging element piece includes a second engaging element piece main surface extending along the direction of the rotation axis and facing the first engaging element piece main surface, and a second engaging element piece side surface extending along the direction of the rotation axis and facing the same direction as the first engaging element piece side surface. An input latching portion is disposed between the first engaging element piece main surface and the second engaging element piece main surface. The first end of the engaging element elastic part may be continuous with the first engaging element piece side surface, and the second end of the engaging element elastic part may be continuous with the second engaging element piece side surface. Also with this configuration, a force in a direction to bring the first and second engaging element pieces closer to each other or a force in a direction to separate the first and second engaging element pieces from each other can be generated.

[0016] In another form of the torque control clutch, the first engaging element piece includes a first engaging element piece main surface extending along the direction of the rotation axis, and the second engaging element piece includes a second engaging element piece main surface extending along the direction of the rotation axis and facing the first engaging element piece main surface. An input latching portion is disposed between the first engaging element piece main surface and the second engaging element piece main surface. The first end of the engaging element elastic part may be continuous with the first engaging element piece main surface, and the second end of the engaging element elastic part may be continuous with the second engaging element piece main surface. According to this configuration, a force in a direction to bring the first and second engaging element pieces closer to each other or a force in a direction to separate the first and second engaging element pieces from each other can be generated.

[0017] In another form of torque control clutch, when the engaging element is accommodated in the output member, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the first distance, and when the engaging element is not accommodated in the output member, the distance from the portion continuous with the first engaging element piece when the engaging element elastic portion does not generate an elastic force to the portion continuous with the second engaging element piece is the second distance, and the first distance may be equal to the second distance.

[0018] In another form of torque control clutch, when the engaging element is accommodated in the output member, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the first distance, and when the engaging element is not accommodated in the output member, the distance from the portion continuous with the first engaging element piece when the engaging element elastic portion does not generate an elastic force to the portion continuous with the second engaging element piece is the second distance, and the first distance may be shorter than the second distance. According to this configuration, in a state where no torque is input from the input member, the engaging element pressing surface can be pressed against the pressed surface.

[0019] In another form of torque control clutch, when the engaging element is accommodated in the output member, the distance from the portion continuous with the first engaging element piece to the portion continuous with the second engaging element piece is the first distance, and when the engaging element is not accommodated in the output member, the distance from the portion continuous with the first engaging element piece when the engaging element elastic portion does not generate an elastic force to the portion continuous with the second engaging element piece is the second distance, and the first distance may be longer than the second distance. According to this configuration, since the input locking portion is inserted between the first and second engaging element pieces to make the first distance longer than the second distance, the input locking portion can always be in contact with the first and second engaging element pieces.

Advantages of the Invention

[0020] The torque control clutch of the present invention can be easily manufactured.

Brief Description of the Drawings

[0021]

Figure 1

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Figure 18

Mode for Carrying Out the Invention

[0022] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are assigned to the same elements, and redundant descriptions are omitted.

[0023] In the following description, the "axial direction" refers to the axial direction of the torque control clutch. The "radial direction" refers to the radial direction of the torque control clutch. The "circumferential direction" refers to the circumferential direction of the torque control clutch. And the "axial direction" of the torque control clutch coincides with the "axial direction" of the input member, the "radial direction" of the torque control clutch coincides with the "radial direction" of the input member, and the "circumferential direction" of the torque control clutch coincides with the "circumferential direction" of the input member. Similarly, the "axial direction" of the torque control clutch coincides with the "axial direction" of the output member, the "radial direction" of the torque control clutch coincides with the "radial direction" of the output member, and the "circumferential direction" of the torque control clutch coincides with the "circumferential direction" of the output member.

[0024] The clutch device 1 shown in Fig. 1 is a reverse input brake mechanism that transmits torque from the input side to the output side and restricts the transmission of torque from the output side to the input side. The clutch device 1 of the first embodiment will be described by taking the lock type that cuts off rotation from the output side as an example. The clutch device 1 can also be made to correspond to the free type by changing its internal configuration. The free type clutch device 1S (see Fig. 13) will be described as the second embodiment. The lock type clutch device 1 includes an input member, an output member, and a pressed member as components. The free type clutch device 1S includes an input member and an output member as components. The free type output member can be regarded as an integrated body of the lock type output member and the pressed member.

[0025] The clutch device 1 of the first embodiment is a so-called lock type torque control clutch. The lock type clutch device 1 transmits torque from the input member 2 to the output member 3, which will be described later. On the other hand, the clutch device 1 restricts the transmission of torque from the output member 3 to the input member 2. The restriction of torque transmission includes not transmitting any torque from the output member 3 to the input member 2 (torque cutoff) and transmitting reduced torque from the output member 3 to the input member 2 (torque suppression). Further, in the following description, when simply referring to "input", it means the input of torque from the input member 2. When simply referring to "reverse input", it means the input of torque from the output member 3. When simply referring to "neutral", it means that there is no input of torque from the input member 2 and no input of torque from the output member 3 either.

[0026] The clutch device 1 can be used as a torque limiter, for example. In short, it is used in such a way that when a torque equal to or greater than a certain value is reversely input, the lock is released. Conventional clutch devices require other components such as friction materials and springs, and the structure is complex. The clutch device 1 according to the first embodiment can block or limit the reverse input torque with a simple structure because the element 4 (engaging element, see FIG. 2) has a spring function. Moreover, by selecting the material and shape of the element 4, the performance of transmitting torque from the input side to the output side and the performance of restricting the transmission of torque from the output side to the input side can be made as desired.

[0027] As shown in FIG. 2, the clutch device 1 has a clutch case 11 and a clutch unit 12.

[0028] The clutch case 11 houses the clutch unit 12. The shape of the clutch case 11 shown in FIG. 2 is cylindrical, but the outer diameter shape of the clutch case 11 is not particularly limited. The clutch case 11 has a case input surface 11a and a case output surface 11b. Further, the clutch case 11 has a case hole 11H extending from the case input surface 11a to the case output surface 11b. The cross-sectional shape of the case hole 11H is circular. The clutch unit 12 is disposed in the case hole 11H.

[0029] The clutch unit 12 has a clutch module 121, an input shaft side bearing 122, and an output shaft side bearing 123. Note that the clutch unit 12 may be defined with only the clutch module 121 as a component. That is, the input shaft side bearing 122 and the output shaft side bearing 123 are arbitrary components that constitute the clutch unit 12. The clutch unit 12 may or may not have the input shaft side bearing 122 and the output shaft side bearing 123. For example, when the input shaft portion 21 and the output shaft portion 31 are supported by a structure different from that of the clutch device 1, the clutch unit 12 does not require the input shaft side bearing 122 and the output shaft side bearing 123.

[0030] The clutch module 121 is the "torque control clutch" referred to in the claims. Note that the clutch device 1 having the clutch module 121 as one of its components may also be referred to as the "torque control clutch" in the claims. The clutch module 121 is composed of four parts. The clutch module 121 has an input member 2, an output member 3, a housing 5 (pressed member), and an element 4 (engager).

[0031] [Input member 2] The input member 2 shown in FIGS. 3(a) and 3(b) receives torque from a drive source such as an electric motor. The input member 2 may be directly connected to the shaft of the drive source. The input member 2 may be connected to the drive source via a plurality of gears, shafts, etc.

[0032] The input member 2 has an input shaft portion 21, a first input latching portion 22A, and a second input latching portion 22B.

[0033] The shape of the input shaft portion 21 is, for example, cylindrical. The shape of the input shaft portion 21 is not limited to a cylinder. The input shaft portion 21 has an input shaft outer peripheral surface 21a and an input shaft main surface 21b. An input shaft side bearing 122 is attached to the input shaft portion 21. The input shaft side bearing 122 abuts against an input shaft portion flange 23 provided on the side of the input shaft main surface 21b on the input shaft outer peripheral surface 21a. The input shaft side bearing 122 is fitted into a case hole 11H of the clutch case 11. Therefore, the input shaft portion 21 is rotatably attached to the clutch case 11 by the input shaft side bearing 122. Further, the rotation axis A of the input shaft portion 21 coincides with the rotation axis A of the input shaft side bearing 122, and the rotation axis A of the input shaft side bearing 122 coincides with the rotation axis A of the clutch case 11. Therefore, the rotation axis A of the input shaft portion 21 coincides with the rotation axis A of the clutch case 11.

[0034] On the main surface 21b of the input shaft portion, first and second input engaging portions 22A and 22B are provided. The first and second input engaging portions 22A and 22B engage with the element 4 and transmit torque from the input member 2 to the element 4. The first and second input engaging portions 22A and 22B are convex portions protruding from the main surface 21b of the input shaft portion. The first and second input engaging portions 22A and 22B are provided symmetrically with respect to the rotation axis A. That is, the first and second input engaging portions 22A and 22B do not overlap with the rotation axis A. The first and second input engaging portions 22A and 22B are radially separated from the rotation axis A by a predetermined distance. The distance from the rotation axis A to the first input engaging portion 22A may be the same as the distance from the rotation axis A to the second input engaging portion 22B. When these distances are the same, good assemblability can be achieved. Note that the distance from the rotation axis A to the first input engaging portion 22A does not necessarily have to be the same as the distance from the rotation axis A to the second input engaging portion 22B and may be different.

[0035] As an example, the cross-sectional shape of the first and second input engaging portions 22A and 22B is a sector. The cross-sectional shape of the first and second input engaging portions 22A and 22B is not limited to a sector and may be a shape different from a sector. Each of the first and second input engaging portions 22A and 22B has an input engaging main surface 22a, an input engaging back surface 22b, a pair of input engaging side surfaces 22c, and a pair of input engaging end surfaces 22d.

[0036] The input engagement main surface 22a is, for example, a plane and contacts the element 4. The input engagement main surface 22a is not limited to a plane and may be, for example, a curved surface. The input engagement main surface 22a of the first input engagement portion 22A faces the input engagement main surface 22a of the second input engagement portion 22B and is, for example, parallel to each other. Note that the input engagement main surface 22a of the first input engagement portion 22A does not necessarily have to be parallel to the input engagement main surface 22a of the second input engagement portion 22B. The input engagement back surface 22b does not contact the element 4. The input engagement back surface 22b that does not contact the element 4 may be a curved surface or may not be a curved surface. For example, the input engagement back surface 22b that does not contact the element 4 may be a plane. The pair of element side surfaces 41c connect the input engagement main surface 22a to the input engagement back surface 22b. The pair of input engagement side surfaces 22c that connect the input engagement main surface 22a to the input engagement back surface 22b may be planes or may not be planes. For example, the pair of input engagement side surfaces 22c that connect the input engagement main surface 22a to the input engagement back surface 22b may be curved surfaces. The angle formed between the input engagement main surface 22a and the input engagement side surface 22c is, for example, an obtuse angle. Note that the angle formed between the input engagement main surface 22a and the input engagement side surface 22c is not limited to an obtuse angle and may be an acute angle. The ridge line between the input engagement main surface 22a and the input engagement side surface 22c can be a fulcrum in the transmission of torque from the input member 2 to the element 4.

[0037] [Output member 3] The output member 3 shown in FIGS. 4(a) and 4(b) receives torque from the input member 2 via the element 4. The output member 3 is connected to a speed reduction mechanism or the like. The output member 3 has an output shaft portion 31 and an output engagement portion 32.

[0038] The shape of the output shaft portion 31 is cylindrical. The output shaft portion 31 has an outer peripheral surface 31a of the output shaft portion and a main surface 31b of the output shaft portion. An output shaft side bearing 123 is attached to the output shaft portion 31. The output shaft side bearing 123 abuts against an output shaft portion flange 33 provided on the side of the main surface 31b of the output shaft portion on the outer peripheral surface 31a of the output shaft portion. The output shaft side bearing 123 is fitted into a case hole 11H of the clutch case 11. Therefore, the output shaft portion 31 is rotatably attached to the clutch case 11 by the output shaft side bearing 123. Further, the rotation axis A of the output shaft portion 31 coincides with the rotation axis A of the output shaft side bearing 123, and the rotation axis A of the output shaft side bearing 123 coincides with the rotation axis A of the clutch case 11. Therefore, the rotation axis A of the output shaft portion 31 coincides with the rotation axis A of the clutch case 11.

[0039] An output engaging portion 32 is provided on the main surface 31b of the output shaft portion. The output engaging portion 32 meshes with the element 4 and receives torque from the element 4. Also, when there is reverse input of torque from the output shaft portion 31, the output engaging portion 32 transmits torque to the element 4.

[0040] The output engaging portion 32 is one convex portion protruding from the main surface 31b of the output shaft portion. The rotation axis A of the output engaging portion 32 coincides with the rotation axis A of the output shaft portion 31. The output engaging portion 32 exhibits a so-called cam function. The cross-sectional shape of the output engaging portion 32 is a flattened oval. That is, the distance from the rotation axis A to the outer peripheral surface of the output engaging portion 32 is not constant in the circumferential direction. The output engaging portion 32 has a pair of output engaging main surfaces 32a and a pair of output engaging peripheral surfaces 32b. For example, the thickness from one output engaging main surface 32a to the other output engaging main surface 32a is shorter than the width from one output engaging peripheral surface 32b to the other output engaging peripheral surface 32b.

[0041] For example, when viewing the first and second input latching portions 22A and 22B and the output latching portion 32 from the direction of the rotation axis A (see Fig. 5(b)), the width of the output latching main surface 32a is larger than the width of the input latching main surface 22a. According to this configuration, the position of the force point in the torque transmission from the input member 2 to the element 4 overlaps with the region where the output latching portion 32 and the element 4 are in contact. Therefore, when transmitting torque from the input member 2 to the output member 3, the occurrence of unintended deformation of the element 4 can be suppressed.

[0042] That the width of the output latching main surface 32a is larger than the width of the input latching main surface 22a means, in other words, that the width of the input latching main surface 22a is narrower than the width of the output latching main surface 32a. In this case, the distance from the rotation axis A, which is the torque axis, to the position where the input latching portions 22A and 22B are in contact with the element 4 (input latching main surface 22a, latching hole main surface 41Ha) is short. Then, since the input latching portions 22A and 22B are pressed against the element 4 with a large force, the output latching portion 32 is strongly sandwiched by the first element piece portion 40A and the second element piece portion 40B. As a result, the intermittent contact between the pressing surface and the pressed surface due to fluctuations in the output-side torque and the like is less likely to occur. Therefore, the torque transmission efficiency is improved.

[0043] Incidentally, contrary to the above configuration, the width of the output locking main surface 32a may be smaller than the width of the input locking main surface 22a. In other words, the width of the input locking main surface 22a may be larger than the width of the output locking main surface 32a. In this case, the distance from the rotational axis line A, which is the torque shaft, to the positions where the input locking portions 22A and 22B contact the element 4 (input locking main surface 22a, locking hole main surface 41Ha) is long. Then, since the input locking portions 22A and 22B are pressed against the element 4 with a small force, the output locking portion 32 is weakly sandwiched between the first element piece portion 40A and the second element piece portion 40B. As a result, intermittent contact between the pressing surface and the pressed surface due to fluctuations in the torque on the output side or the like is likely to occur. Therefore, the torque transmission efficiency is inferior to the above configuration. On the other hand, when reverse input of torque occurs from the output shaft portion 31, the element 4 presses the input locking portions 22A and 22B with a weak force. As a result, contact between the pressing surface and the pressed surface starts before the torque is transmitted to the input shaft portion 21. Then, since the output shaft portion 31 is locked while the rotation angle of the output shaft portion 31 is small, an angular deviation due to reverse input of torque is unlikely to occur. That is, high positioning accuracy can be obtained.

[0044] [Housing 5] As shown in FIG. 2, the housing 5 houses the element 4. When torque is transmitted to the element 4 via the input member 2, the force applied from the element 4 to the housing 5 decreases. As a result, the element 4 can rotate with respect to the housing 5. On the other hand, when torque is transmitted to the element 4 via the output member 3 (reverse input), the force applied from the element 4 to the housing 5 increases. As a result, the rotation of the element 4 with respect to the housing 5 is suppressed.

[0045] The shape of the housing 5 is a thin-walled cylinder. The housing 5 is made of, for example, metal. The housing 5 has a housing outer peripheral surface 51a, an input-side main surface 51b, an output-side main surface 51c, and a housing inner peripheral surface 51d (pressed surface). The housing outer peripheral surface 51a faces the inner peripheral surface of the case hole 11H in the clutch case 11. The input-side main surface 51b faces the input shaft-side bearing 122. The planar shape of the input-side main surface 51b is a circle. The outer diameter of the input-side main surface 51b may be the same as the outer diameter of the input shaft-side bearing 122. The output-side main surface 51c faces the output shaft-side bearing 123. The planar shape of the output-side main surface 51c is also a circle. The outer diameter of the output-side main surface 51c may be the same as the outer diameter of the output shaft-side bearing 123.

[0046] The element 4 is pressed against the housing inner peripheral surface 51d during reverse input. The housing inner peripheral surface 51d faces the outer peripheral surface of the element 4. When in a neutral state with no torque input from either the input member 2 or the output member 3, the element 4 is in contact with a part of the housing inner peripheral surface 51d. Also, when in the neutral state, the element 4 is not in contact with another part of the housing inner peripheral surface 51d. (See Fig. 6).

[0047] [Element 4] The element 4 shown in Figs. 5(a) and 5(b) transmits torque to the output member 3 when receiving torque input from the input member 2. On the other hand, the element 4 blocks or suppresses the transmission of torque to the input member 2 when receiving torque input (reverse input) from the output member 3. The element 4 has first and second element piece parts 40A, 40B (first engaging piece part, second engaging piece part) and first and second element spring parts 43A, 43B (engaging piece elastic part). The element 4 is an integral part formed of a resin material or a metal material.

[0048] By selecting the type of material that composes Element 4, the mode of torque transmission can be adjusted arbitrarily. For example, when Element 4 is composed of a metal material, rapid torque switching due to high rigidity characteristics can be achieved. Furthermore, it can withstand high-torque reverse input. And complete blocking of reverse input torque is also possible. For example, when Element 4 is composed of a resin material, gentle torque switching due to low rigidity characteristics can be achieved.

[0049] Element 4, which is an integral part composed of a metal material, can be manufactured by machining, pressing, forging, sintering, or the like. Element 4, which is an integral part formed of a resin material, can be obtained by an injection molding method or a laminated manufacturing method using a so-called 3D printer.

[0050] In addition to selecting the type of material that composes Element 4, by adjusting the gap between the housing 5 (pressed member) and Element 4 (engaging element), the shape of Element 4, the shapes of the first and second element spring portions 43A and 43B, etc., torque transmission control can be achieved according to various requirements.

[0051] The shape of Element 4 in plan view is substantially circular. That is, the shape of Element 4 is a thin substantially circular plate. The thickness of Element 4 may be substantially the same as the thickness of the housing 5. Therefore, the end faces (element input surface 41a and element output surface 41b) of Element 4 are generally flush with the end faces (input side main surface 51b, output side main surface 51c) of the housing 5.

[0052] When there is a reverse input of torque, the first and second element piece portions 40A and 40B cooperate with the inner peripheral surface 51d of the housing to generate a braking torque that counteracts the reverse input torque. The first element piece portion 40A has a first element main body portion 41A and a first element convex portion 42A. Similarly, the second element piece portion 40B has a second element main body portion 41B and a second element convex portion 42B.

[0053] The shapes of the first and second element main bodies 41A and 41B in plan view are each substantially semi-circular. The first and second element main bodies 41A and 41B are symmetrically arranged with the rotation axis A interposed therebetween. Each of the first and second element main bodies 41A and 41B has an element input surface 41a, an element output surface 41b, an element side surface 41c, and an element pressing surface 41d (engagement element pressing surface).

[0054] The element input surface 41a faces the input shaft portion main surface 21b. From the side of the element input surface 41a, the first and second input latching portions 22A and 22B are inserted into the element 4. The element input surface 41a may contact the input shaft portion main surface 21b or may be slightly spaced apart therefrom. The element output surface 41b faces the output shaft portion main surface 31b. From the side of the element output surface 41b, the output latching portion 32 is inserted into the element 4. The element output surface 41b may contact the output shaft portion main surface 31b or may be slightly spaced apart therefrom. The element side surface 41c connects one end of the arc-shaped element pressing surface 41d to the other end. The element side surface 41c is parallel to and spaced from an axis orthogonal to the rotation axis A. The element pressing surface 41d faces the inner peripheral surface 51d of the housing. The element pressing surface 41d has a contact portion 41d1 that contacts the inner peripheral surface 51d of the housing in a neutral state and a non-contact portion 41d2 that does not contact the inner peripheral surface 51d of the housing.

[0055] The first and second element main bodies 41A and 41B each have an input latching hole 41H. The input latching hole 41H is a through hole extending from the element input surface 41a to the element output surface 41b. The first input latching portion 22A is inserted into the input latching hole 41H of the first element main body 41A. The second input latching portion 22B is inserted into the input latching hole 41H of the second element main body 41B. The shape of the input latching hole 41H in plan view is substantially semi-circular. The input latching hole 41H is a region surrounded by a latching hole main surface 41Ha which is a plane and a latching hole inner peripheral surface 41Hb which is a curved surface. The latching hole main surface 41Ha is parallel to an axis orthogonal to the rotation axis A and is spaced apart from the axis. The input latching main surface 22a contacts the latching hole main surface 41Ha. That is, when the input member 2 receives torque input, the first and second input latching portions 22A and 22B are pressed against the latching hole main surface 41Ha to receive torque transmission. The latching hole inner peripheral surface 41Hb faces the input latching back surface 22b. The latching hole inner peripheral surface 41Hb does not contact the input latching back surface 22b. That is, a gap exists between the latching hole inner peripheral surface 41Hb and the input latching back surface 22b.

[0056] The first and second element convex portions 42A and 42B each have an element convex portion main surface 42a (engagement piece portion main surface) and an element convex portion side surface 42b (engagement piece portion side surface). The element convex portion main surface 42a has a portion facing the output latching main surface 32a. When receiving torque input from the input member 2, the element convex portion main surface 42a is pressed against the output latching main surface 32a. That is, the element convex portion main surface 42a transmits the torque received from the input member 2 to the output member 3. The respective element convex portion main surfaces 42a of the first and second element convex portions 42A and 42B sandwich the output latching portion 32. In the neutral state, the element convex portion main surface 42a is slightly spaced apart from the output latching main surface 32a. The element convex portion main surface 42a of the first element convex portion 42A also has a portion facing the element convex portion main surface 42a of the second element convex portion 42B.

[0057] The first and second element body parts 41A and 41B, which have moved so as to be pressed against the housing 5 upon the occurrence of a reverse input, are each returned to their initial positions upon the release of the reverse input. In other words, the first and second element spring parts 43A and 43B generate a force that brings the first and second element body parts 41A and 41B closer to each other. Note that the "initial position" means the positions of the first and second element body parts 41A and 41B when in a neutral state.

[0058] The first and second element spring parts 43A and 43B are disposed between the first element body part 41A and the second element body part 41B. The first and second element spring parts 43A and 43B are connected to the first and second element body parts 41A and 41B via first and second element convex parts 42A and 42B that extend in the radial direction. The first and second element convex parts 42A and 42B respectively project from the element side surfaces 41c of the first and second element body parts 41A and 41B. The widths of the first and second element convex parts 42A and 42B are greater than the width of the output latching main surface 32a (output latching part 32). Further, the widths of the first and second element convex parts 42A and 42B may be greater than the width of the input latching main surface 22a (input latching parts 22A and 22B). Note that the widths of the first and second element convex parts 42A and 42B may also be smaller than the width of the input latching main surface 22a (input latching parts 22A and 22B).

[0059] The ends of the first and second element spring parts 43A and 43B are connected to the tips of the element convex part side surfaces 42b. The shapes of the first and second element spring parts 43A and 43B in plan view are U-shaped. The first and second element spring parts 43A and 43B each have a first beam part 43a, a second beam part 43b, and an arc part 43c. The first end 43a1 of the first beam part 43a is connected to the first element convex part 42A. The second end 43b1 of the second beam part 43b is connected to the second element convex part 42B.

[0060] Here, in a state where the element 4 is disposed in the housing 5 (see Fig. 6(a)), let the distance from the first end portion 43a1 of the first beam portion 43a to the second end portion 43b1 of the second beam portion 43b be the first distance L1. And in a state where the element 4 is not disposed in the housing 5 (see Fig. 5(b)), let the distance from the first end portion 43a1 of the first beam portion 43a to the second end portion 43b1 of the second beam portion 43b be the second distance L2. Note that the second distance L2 can also be said to be the separation distance from one element convex portion main surface 42a to the other element convex portion main surface 42a. When comparing this first distance L1 and the second distance L2, the first distance L1 when the element 4 is in a state of being disposed in the housing 5 is equal to the second distance L2 when the element 4 is in a state of not being disposed in the housing 5.

[0061] [Explanation of the operation of the clutch device Part 1 (when torque is input to the input member 2)] When the input member 2 receives torque from the drive source, as shown in Fig. 6(b), the first and second input latching portions 22A, 22B inserted into the pair of input latching holes 41H rotate (see the arrow CW in Fig. 6(b)). Due to this rotation, the first and second input latching portions 22A, 22B of the input member 2 exert a force F1T on the pair of latching hole main surfaces 41Ha of the element 4. By the force F1T, the upper first element main body portion 41A in Fig. 6(b) moves downward, and by the force F1T, the lower second element main body portion 41B in Fig. 6(b) moves upward. That is, the first element main body portion 41A and the second element main body portion 41B approach each other. In other words, the gap between the element side surface 41c of the first element main body portion 41A and the element side surface 41c of the second element main body portion 41B narrows.

[0062] According to the operation in which the first and second element main bodies 41A and 41B approach each other, the first and second element convex portions 42A and 42B sandwich the output latching portion 32 of the output member 3. Specifically, each element convex portion main surface 42a of the first and second element convex portions 42A and 42B is pressed against the output latching main surface 32a of the output member 3. In this state, the output latching portion 32 receives a force at a position separated from the rotation axis A by a predetermined distance. Therefore, the output latching portion 32 receives a torque defined by the product of the predetermined distance and the force. As a result, the torque of the input member 2 is transmitted to the output member 3.

[0063] In addition, the above description is an example when the input member 2 rotates in the clockwise direction (see the arrow CW in FIG. 6) as shown in FIG. 6. The above description also holds when the input member 2 rotates in the counterclockwise direction.

[0064] [Explanation of the operation of the clutch device Part 2 (when torque is reversely input to the output member 3)] When the output member 3 receives torque, as shown in FIG. 7, the output latching portion 32 inserted between the first and second element convex portions 42A and 42B rotates (see the arrow CW in FIG. 7). By this rotation, the output latching portion 32 exerts a force F2T on the first and second element convex portions 42A and 42B. Due to the force F2T, the upper first element main body 41A in FIG. 7 moves upward, and due to the force F2T, the lower second element main body 41B in FIG. 7 moves downward. That is, the first element main body 41A and the second element main body 41B move away from each other. In other words, the gap between the element side surface 41c of the first element main body 41A and the element side surface 41c of the second element main body 41B increases.

[0065] The operation in which the first and second element main bodies 41A and 41B move away from each other has one effect. That is, the operation in which the first and second element main bodies 41A and 41B move away from each other generates braking torque. Specifically, when the upper first element main body 41A moves upward, the element pressing surface 41d is pressed against the inner peripheral surface 51d of the housing 5 of the housing. Specifically, the element pressing surface 41d exerts a force F3T on the inner peripheral surface 51d of the housing. The braking torque is caused by the frictional force between the element 4 and the housing 5. Since the frictional force is proportional to the force F3T (normal reaction force) exerted by the element pressing surface 41d on the inner peripheral surface 51d of the housing, the braking torque (frictional force) increases as the force F3T increases.

[0066] When the braking torque is equal to the reverse input torque from the output member 3, the element 4 does not move relative to the housing 5. That is, the transmission of torque from the output member 3 to the input member 2 is completely blocked. The state in which the element 4 does not move relative to the housing 5 is referred to as "lock". On the other hand, when the braking torque is smaller than the reverse input torque from the output member 3, the element 4 can move relative to the housing 5. That is, the reduced torque is transmitted from the output member 3 to the input member 2. The state in which the reduced torque is transmitted from the output member 3 to the input member 2 is referred to as "semi-lock". The relationship between the braking torque and the reverse input torque can be controlled by several parameters. Examples of the parameters will be described later as modification examples, such as the magnitude of the preload in the neutral state, the coefficient of friction between the element pressing surface 41d and the inner peripheral surface 51d of the housing, and the elastic coefficients of the first and second element spring portions 43A and 43B.

[0067] For example, as shown in the graph G6a of FIG. 8(a), when a reverse input torque is applied, as long as the braking torque generated is always equal to the reverse input torque regardless of the magnitude of the reverse input torque and does not exceed the breaking strength of each component, the reverse input torque continues to be blocked. For example, when a relatively small reverse input torque (R1) is applied, a braking torque (B1) of the same magnitude is generated. Similarly, when a relatively large reverse input torque (R2) is applied, a braking torque (B2a) of the same magnitude is generated. The loss of the braking function occurs when a torque equal to or greater than the limit value of the braking performance is input or when a component breaks.

[0068] On the other hand, as shown in the graph G6b of FIG. 8(b), in a state where the reverse input torque is small (S6a), a braking torque equal to the reverse input torque can be generated, but in a state where the reverse input torque is large (S6b), it may not be possible to generate a braking torque equal to the reverse input torque. In this case, the torque of the difference between the reverse input torque and the braking torque is transmitted from the output member 3 to the input member 2. For example, when a relatively small reverse input torque (R1) is applied, a braking torque (B1) of the same magnitude is generated. On the other hand, when a relatively large reverse input torque (R2) is applied, a braking torque (B2b) smaller than the reverse input torque (R2) is generated. In this case, a part of the reverse input torque is transmitted from the output member 3 to the input member 2.

[0069] FIG. 8(b) shows the relationship between the reverse input torque and the torque transmitted to the input member 2. For example, as shown in the graph G6c, when the element 4 is formed of a metal material (when formed of a material with a relatively large elastic modulus), as long as the breaking strength of each component is not exceeded, a braking torque of the same magnitude as the reverse input torque can be generated regardless of the magnitude of the reverse input torque. As a result, the transmission of torque from the output member 3 to the input member 2 continues to be blocked. That is, the transmitted torque is in the above-mentioned "locked" state and is always zero regardless of the magnitude of the reverse input torque.

[0070] On the one hand, as shown in graph G6d, when element 4 is formed of a resin material (when formed of a material with a relatively small elastic modulus), in the case of a relatively small reverse input torque, the transmission of torque from output member 3 to input member 2 is blocked. That is, the transmitted torque is in the "locked" state as described above and is zero in the case of a relatively small reverse input torque. On the other hand, in the case of a relatively large reverse input torque, it is in the "semi-locked" state as described above, and torque is transmitted from output member 3 to input member 2.

[0071] [Function and effect] Clutch device 1 is provided so as to sandwich the rotation axis A, and includes an input member 2 including first and second input latching portions 22A and 22B extending along the rotation axis A, and is coaxial with the rotation axis A. An output member 3 including an output latching portion 32 having a flat cross-sectional shape perpendicular to the rotation axis A and extending along the rotation axis A, and the first and second input latching portions 22A and 22B are inserted so as to sandwich the rotation axis A. And an element 4 capable of sandwiching the output latching portion 32 between the inserted first and second input latching portions 22A and 22B, and a housing inner peripheral surface 51d facing the element 4, and a housing 5 for accommodating the element 4. Element 4 includes an element pressing surface 41d facing the housing inner peripheral surface 51d and input latching holes 41H into which the first and second input latching portions 22A and 22B are inserted, and first and second elements disposed with the output member 3 interposed therebetween. Element pieces 40A and 40B, a portion continuous with the first element piece 40A and a portion continuous with the second element piece 40B, and first and second element spring portions 43A and 43B disposed between the first element piece 40A and the second element piece 40B. It is an integrally molded product having

[0072] The clutch device 1 allows the transmission of torque from the input member 2 to the output member 3 and restricts the reverse input of torque from the output member 3 to the input member 2. The element 4 for performing the functions of transmitting torque and restricting the reverse input of torque is configured as an integral part including first and second element piece portions 40A and 40B and first and second element spring portions 43A and 43B. Therefore, the clutch device 1 described above can be easily manufactured because the number of parts is small.

[0073] Conventional clutch devices for restricting reverse input torque have a problem that the cost is high because the number of components is large and the assembly is complicated. The clutch device 1 of the first embodiment has an integral structure for the element 4 (engager) that forms the core of the locking mechanism. As a result, the clutch device 1 can be composed of the input member 2, the output member 3, the housing 5 (pressed member), and the element 4 (engager), so that it is possible to achieve both reduction of components and reverse input brake control. And by making the element 4, which is an engager, an integral body including springs (first and second element spring portions 43A and 43B), the structure of the element 4 can be simplified. As a result, the assemblability and the number of parts of the clutch device 1 can be reduced.

[0074] The clutch device 1 of the first embodiment is composed of four parts: an input member 2, an output member 3, an element 4, and a housing 5. When the input member 2 is rotated, the element 4 (engager) with first and second element spring portions 43A and 43B (engager elastic portions) is deformed so as to be separated from the inner peripheral surface 51d of the housing of the housing 5 (pressed member). As a result, the element 4 rotates in accordance with the rotation of the input member 2. And since the element 4 sandwiches the output member 3 by the first and second element piece portions 40A and 40B, the output member 3 also rotates in accordance with the rotation of the element 4. As a result, the torque from the input side is transmitted. On the other hand, when the output member 3 is rotated, the output member 3 expands the element 4, thereby generating a braking torque that counteracts the torque reversely input from the element 4.

[0075] The first element piece portion 40A includes a first element convex portion main surface 42a extending along the direction of the rotation axis A, and a first element convex portion side surface 42b extending along the direction of the rotation axis A and facing a direction different from that of the first element convex portion main surface 42a. The second element piece portion 40B includes a second element convex portion main surface 42a extending along the direction of the rotation axis A and facing the first element convex portion main surface 42a, and a second element convex portion side surface 42b extending along the direction of the rotation axis A and facing the same direction as the first element convex portion side surface 42b. An output latching portion 32 is disposed between the first element convex portion main surface 42a and the second element convex portion main surface 42a. A first end portion 43a1 of the first element spring portion 43A is continuous with the first element convex portion side surface 42b. A second end portion 43b1 of the first element spring portion 43A is continuous with the second element convex portion side surface 42b. According to this configuration, a force in a direction to bring the first and second element piece portions 40A, 40B closer to each other or a force in a direction to separate the first and second element piece portions 40A, 40B from each other can be generated.

[0076] When the element 4 is accommodated in the housing 5, the clutch device 1 sets the distance from the portion continuous with the first element piece portion 40A to the portion continuous with the second element piece portion 40B as a first distance L1. When the element 4 is not accommodated in the housing 5, the distance from the portion continuous with the first element piece portion 40A to the portion continuous with the second element piece portion 40B when the element spring portions 43A, 43B do not generate an elastic force is set as a second distance L2. The first distance L1 is equal to the second distance L2. According to this configuration, in a state where no torque is input from the input member 2, the element pressing surface 41d can be prevented from being pressed against the inner peripheral surface 51d of the housing, that is, the preload can be set to zero. When the preload is zero, the loss of the input torque can be minimized. Theoretically, when the preload is zero, the loss of the input torque can be set to zero.

[0077] The lock-type torque control clutch device 1 of the first embodiment is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention. The lock-type clutch device 1 of the first embodiment can also adopt the configurations of Modifications 1 to 5.

[0078] [Modification 1] For example, the clutch device 1F of Modification 1 may have an element 4F shown in FIGS. 9 and 10 instead of the element 4 shown in FIG. 2 and the like. The clutch device 1F of the modification is different from the clutch device 1 of the embodiment in that the element 4F is different. Specifically, the element 4F of the modification is different from the element 4 of the embodiment in that the first and second element spring portions 44F1 and 44F2 are different. In the clutch device 1F of the modification, the configurations of the input member 2, the output member 3, the housing 5, the input shaft side bearing 122, the output shaft side bearing 123, and the clutch case 11 are the same as those of the clutch device 1 of the embodiment. Hereinafter, the first and second element spring portions 44F1 and 44F2 will be described with attention.

[0079] As shown in FIGS. 10(a) and 10(b), the element 4F has first and second element piece portions 40FA and 40FB, and first and second element spring portions 44F1 and 44F2. The first element piece portion 40FA has a first element main body portion 41F1 and a first element convex portion 42F1. Similarly, the second element piece portion 40FB has a second element main body portion 41F2 and a second element convex portion 42F2. Since the configurations of the first and second element main body portions 41F1 and 41F2 and the first and second element convex portions 42F1 and 42F2 are the same as those of the first and second element main body portions 41A and 41B and the first and second element convex portions 42A and 42B of the embodiment, detailed description thereof will be omitted.

[0080] The first and second element spring portions 44F1 and 44F2 of the modified example also function as so-called compression springs. The shape of the first and second element spring portions 44F1 and 44F2 in a plan view is V-shaped. Each of the first and second element spring portions 44F1 and 44F2 has a first beam portion 44a, a second beam portion 44b, and a bent portion 44c. The first end portion 44a1 of the first beam portion 44a is connected to the element side surface 41c (the main surface of the first engaging piece portion) of the first element main body portion 41F1. The second end portion 44b1 of the second beam portion 44b is connected to the element side surface 41c (the main surface of the second engaging piece portion) of the second element main body portion 41F2. In the examples shown in FIGS. 10(a) and 10(b), the first end portion 44a1 and the second end portion 44b1 are located outside in the radial direction from the bent portion 44c. According to this configuration, the restoring force generated by the first and second element spring portions 44F1 and 44F2 acts on the first element main body portion 41F1 at the position of the first end portion 44a1 and acts on the second element main body portion 41F2 at the position of the second end portion 44b1.

[0081] In the clutch device 1F of the modified example, the first element piece portion 40A includes a first element convex portion main surface 42a extending along the direction of the rotation axis A. The second element piece portion 40B extends along the direction of the rotation axis A and includes a second element convex portion main surface 42a facing the first element convex portion main surface 42a. An output latching portion 32 is disposed between the first element convex portion main surface 42a and the second element convex portion main surface 42a. The first ends of the element spring portions 44F1 and 44F2 are continuous with the element side surface 41c of the first element main body portion 41F1. The second ends of the element spring portions 44F1 and 44F2 are continuous with the element side surface 41c of the second element main body portion 41F2. According to this configuration, a force in a direction to bring the first and second element piece portions 40A and 40B closer to each other or a force in a direction to separate the first and second element piece portions 40A and 40B from each other can be generated.

[0082] Note that the element 4F included in the clutch device 1F of Modification 1 can also be applied to the clutch device 1S of the second embodiment described later.

[0083] [Modification 2] <Structure of Modification 2> As shown in Fig. 11(a), the clutch device 1A of Modification 2 includes an element 4A and a housing 5A. In a state where the element 4A is disposed in the housing 5A, the distance from the end 43a1 of the first beam portion 43a to the end 43b1 of the second beam portion 43b is a first distance L1A. The first distance L1A when the element 4A is disposed in the housing 5A is shorter than a second distance L2 (see Fig. 5(b)) when the element 4A is not disposed in the housing 5A.

[0084] <Relationship between the housing and preload in Modification 2> The element spring portions 43A and 43B of the clutch device 1A of Modification 2 generate a preload F3N that presses the first and second element piece portions 40A and 40B against the housing 5A when in a neutral state.

[0085] <Relationship between the output locking portion and the clamping force in Modification 2> The clutch device 1A of Modification 2 has a gap formed between the output locking portion 32A and the first element piece portion 40A, and between the output locking portion 32A and the second element piece portion 40B when in a neutral state. More specifically, the clutch device 1A of Modification 2 has a predetermined gap formed between the main surface 42a of the element convex portion and the main surface 32a of the output locking portion. The output locking portion 32 of the clutch device 1A of Modification 2 does not receive a clamping force F1N from the first and second element piece portions 40A and 40B.

[0086] <Operational effects of Modification 2> According to the configuration with a gap that the clutch device 1A of Modification 2 has, the first and second element pieces 40A and 40B can be closer to each other. As a result, the preload F3N weakens, so the braking torque (frictional force) generated between the element 4A and the housing 5A weakens. Therefore, the clutch device 1A of Modification 2 can transmit a predetermined torque from the input side to the output side by sandwiching the output locking portion 32A between the first element convex portion 42A and the second element convex portion 42B. The magnitude of the preload F3N when there is an input of torque from the input side only needs to be smaller than the magnitude of the preload F3N in the neutral state. For example, the magnitude of the preload F3N when there is an input of torque from the input side may be a predetermined magnitude smaller than the magnitude of the preload F3N in the neutral state. In this case, the torque attenuated by the amount of the braking torque corresponding to the weakened preload F3N is transmitted to the output side. The magnitude of the weakened preload F3N may be zero. In this case, a slight gap is generated between the inner peripheral surface 51d of the housing and the element pressing surface 41d. That is, since no braking torque is generated between the element 4A and the housing 5A, the torque input from the input side (input member 2) is transmitted to the output side (output member 3) without attenuation.

[0087] [Modification 3] <Structure of Modification 3> As shown in FIG. 11(b), the clutch device 1B of Modification 3 includes an element 4B and a housing 5B. In a state where the element 4B is disposed in the housing 5B, the distance from the end 43a1 of the first beam portion 43a to the end 43b1 of the second beam portion 43b is the first distance L1B. The first distance L1B when the element 4B is disposed in the housing 5B is shorter than the second distance L2 (see FIG. 5(b)) when the element 4B is not disposed in the housing 5B.

[0088] <Relationship between the housing and the preload in Modification 3> When the clutch device 1B of Modification 3 is in the neutral state, the element spring portions 43A and 43B generate a preload F3N that presses the first and second element piece portions 40A and 40B against the housing 5B.

[0089] <Relationship between the output engaging portion and the clamping force in Modification 3> The clutch device 1A of Modification 2 had a predetermined gap formed between the main surface 42a of the element convex portion and the main surface 32a of the output engaging portion. The clutch device 1B of Modification 3 has no gap formed between the output engaging portion 32B and the first element piece portion 40A, and between the output engaging portion 32B and the second element piece portion 40B when in the neutral state. More specifically, the main surface 42a of the element convex portion of the clutch device 1B of Modification 3 is pressed against the main surface 32a of the output engaging portion. According to this configuration, the output engaging portion 32 of the clutch device 1B of Modification 3 receives a clamping force F1N from the first and second element piece portions 40A and 40B.

[0090] <Operating effects of Modification 3> In the clutch device 1A of Modification 2, the first and second element piece portions 40A and 40B cannot approach each other. Therefore, in the clutch device 1A of Modification 2, the preload F3N does not decrease even when torque is input from the input side. As a result, in the clutch device 1A of Modification 2, torque attenuated by the amount of braking torque corresponding to the preload F3N is transmitted to the output side. On the other hand, in the clutch device 1B of Modification 3, the first and second element piece portions 40A and 40B are in contact with the output engaging portion 32B respectively when in the neutral state. As a result, the clutch device 1B of Modification 3 can block the transmission of torque to the input side without delay in response to reverse input of torque from the output side. In other words, the clutch device 1B of Modification 3 can improve the responsiveness to reverse input of torque from the output side.

[0091] [Modification 4] <Structure of Modification 4> As shown in Fig. 12(a), the clutch device 1C of Modification 4 includes an element 4C and a housing 5C. In a state where the element 4C is disposed in the housing 5C, the distance from the end 43a1 of the first beam portion 43a to the end 43b1 of the second beam portion 43b is the first distance L1C. The first distance L1C when the element 4C is disposed in the housing 5C is longer than the second distance L2 (see Fig. 5(b)) when the element 4C is not disposed in the housing 5C. This is because an output latching portion 32C having a thickness longer than the second distance L2 is inserted between the first and second element pieces 40A and 40B. Specifically, the thickness of the output latching portion 32C is longer than the second distance L2. When the output latching portion 32C is inserted between the first and second element pieces 40A and 40B, the distance from the first element piece 40A to the second element piece 40B becomes the same as the thickness of the output latching portion 32C. That is, the gap between the first element piece 40A and the second element piece 40B is expanded by the output latching portion 32C, so that the first distance L1C becomes longer than the second distance L2.

[0092] <Relationship between the housing and the preload in Modification 4> The inner diameter of the housing 5C in the clutch device 1C of Modification 4 is slightly larger than the outer diameter of the element 4 into which the output latching portion 32C is inserted. In the clutch device 1C of Modification 4, when in the neutral state, the element pressing surface 41d is not pressed against the housing inner peripheral surface 51d. More specifically, the element pressing surface 41d of the clutch device 1C of Modification 4 may be slightly separated from the housing inner peripheral surface 51d. That is, in the clutch device 1C of Modification 4, the preload F3N does not occur.

[0093] <Relationship between the output latching portion and the clamping force in Modification 4> When the clutch device 1C of Modification 4 is in the neutral state, no gap is formed between the output latching portion 32C and the first element piece portion 40A, and between the output latching portion 32C and the second element piece portion 40B. More specifically, the main surface 42a of the element convex portion of the clutch device 1C of Modification 4 is pressed against the main surface 32a of the output latching. According to this configuration, the output latching portion 32C of the clutch device 1C of Modification 4 receives the clamping force F1N from the first and second element piece portions 40A and 40B.

[0094] <Operational Effects of Modification 4> The output latching portion 32C in the clutch device 1C of Modification 4 is always in contact with the first and second element piece portions 40A and 40B when in the neutral state. As a result, the clutch device 1C of Modification 4 can cut off the transmission of torque to the input side without delay in response to reverse input of torque from the output side. In other words, the clutch device 1C of Modification 4 can enhance the responsiveness to reverse input of torque from the output side. Furthermore, in the clutch device 1C of Modification 4, there is no preload F3N. As a result, when in the neutral state, there is no braking torque in the clutch device 1C of Modification 4. Therefore, the torque from the input side is transmitted to the output side without being attenuated by the braking torque.

[0095] [Modification 5] <Structure of Modification 5> As shown in Fig. 12(b), the clutch device 1D of Modification 5 includes an element 4D and a housing 5D. When the element 4D is disposed in the housing 5D, the distance from the end 43a1 of the first beam portion 43a to the end 43b1 of the second beam portion 43b is the first distance L1D. The first distance L1D when the element 4D is disposed in the housing 5D is longer than the second distance L2 (see Fig. 5(b)) when the element 4D is not disposed in the housing 5D. This is because an output latching portion 32D having a thickness longer than the second distance L2 is inserted between the first and second element piece portions 40A and 40B.

[0096] <Relationship between the housing and the preload in Modified Example 5> In the clutch device 1C of Modified Example 4, the element pressing surface 41d was not pressed against the inner peripheral surface 51d of the housing. In the clutch device 1D of Modified Example 5 shown in FIG. 12(b), the first and second element pieces 40A and 40B are pressed against the inner peripheral surface 51d of the housing. According to this configuration, when the element spring portions 43A and 43B of the clutch device 1D of Modified Example 5 are in the neutral state, a preload F3N is generated that presses the first and second element pieces 40A and 40B against the housing 5B.

[0097] <Relationship between the output locking portion and the clamping force in Modified Example 5> In the clutch device 1D of Modified Example 5, when in the neutral state, no gap is formed between the output locking portion 32D and the first element piece 40A, and between the output locking portion 32D and the second element piece 40B. More specifically, the main surface 42a of the element convex portion of the clutch device 1D of Modified Example 5 is pressed against the main surface 32a of the output locking portion. According to this configuration, the output locking portion 32D of the clutch device 1D of Modified Example 5 receives a clamping force F1N from the first and second element pieces 40A and 40B.

[0098] <Operational effects of Modified Example 5> When the clutch device 1D of Modification 5 is in the neutral state, the first element piece portion 40A contacts the output locking portion 32D, and the second element piece portion 40B contacts the output locking portion 32D. As a result, the clutch device 1D of Modification 5 can block the transmission of torque to the input side without delay with respect to the reverse input of torque from the output side. In other words, the clutch device 1D of Modification 5 can enhance the responsiveness to the reverse input of torque from the output side. Also, similar to the clutch device 1C of Modification 4, the output locking portion 32D of the clutch device 1D of Modification 5 always contacts the first and second element piece portions 40A and 40B. Therefore, in the clutch device 1D of Modification 5, the first and second element piece portions 40A and 40B do not approach each other. That is, in the clutch device 1D of Modification 5, the preload F3N is not reduced even by the input of torque from the input side. Therefore, since the preload F3N exists when the clutch device 1D of Modification 5 is in the neutral state, the torque from the input side is always reduced by only the braking torque corresponding to the preload F3N and is transmitted to the output side.

[0099] [Second Embodiment] The clutch device 1 of the first embodiment was a so-called lock-type torque control clutch. The clutch device 1S of the second embodiment shown in FIGS. 13 and 14 is a so-called free-type torque control clutch. The free-type clutch device 1S also allows the transmission of torque from the input member 2S to the output member 3S and restricts the transmission of torque from the output member 3S to the input member 2S.

[0100] The clutch device 1S includes a clutch case 11 and a clutch unit 12S. Since the configuration of the clutch case 11 of the second embodiment is the same as the configuration of the clutch case 11 of the first embodiment, a detailed description thereof will be omitted.

[0101] The clutch unit 12S includes a clutch module 121S, an input shaft side bearing 122, and an output shaft side bearing 123. The clutch module 121S is composed of three parts. The clutch module 121S includes an input member 2S, an output member 3S, and an element 4.

[0102] The configurations of the input member 2S and the input shaft side bearing 122 in the second embodiment are the same as those of the output member 3 and the output shaft side bearing 123 in the first embodiment. That is, the input member 2S has an input shaft portion 21S and an input latching portion 22S. The input shaft portion 21S corresponds to the output shaft portion 31 in the output member 3 of the first embodiment. The input latching portion 22S corresponds to the output latching portion 32 in the output member 3 of the first embodiment. And the input latching portion 22S is inserted between the first and second element convex portions 42A and 42B in the element 4.

[0103] In the clutch device 1 of the first embodiment, the element 4 disposed in the housing 5 was in a state where no preload was generated. In the clutch device 1S of the second embodiment as well, the element 4 disposed in the output member 3S may also be in a state where no preload is generated.

[0104] When no preload is generated between the output member 3S and the element 4, the element 4 is in the state described below. That is, in the state where the element 4 is disposed in the output member 3S (see FIG. 16), the distance from the end portion 43a1 of the first beam portion 43a to the end portion 43b1 of the second beam portion 43b is defined as a first distance L1. And in the state where the element 4 is not disposed in the output member 3S (see FIG. 5(b)), the distance from the end portion 43a1 of the first beam portion 43a to the end portion 43b1 of the second beam portion 43b is defined as a second distance L2. Note that the second distance L2 can also be said to be the separation distance from one element convex portion main surface 42a to the other element convex portion main surface 42a. Comparing this first distance L1 and the second distance L2, the first distance L1 when the element 4 is in the state of being disposed in the housing 5 is equal to the second distance L2 when the element 4 is not in the state of being disposed in the housing 5. Further, the inner diameter of the housing portion 35S is slightly larger than the outer diameter of the element 4 into which the input latching portion 22S is inserted. According to these configurations, in a state where no torque is input from the input member 2S, it is possible to set a state where no preload is generated between the inner peripheral surface 51d of the housing and the element pressing surface 41d.

[0105] The configuration of the single element 4 in the second embodiment is the same as that of the single element 4 in the first embodiment. In FIGS. 13 to 16, an input latching hole 41H is shown in the element 4, but the input latching hole 41H does not perform a special function in the free clutch device 1S. Therefore, in the free clutch device 1S, the input latching hole 41H can be omitted.

[0106] In the free clutch device 1S, the output member 3S can be regarded as an integrated body of the output member 3 of the locking clutch device 1 and the housing 5. In the free clutch device 1S, in response to the rotation of the input member 2S, the element pressing surfaces 41d of the first and second element main body portions 41A, 41B are pressed against the inner peripheral surface 35d of the housing of the output member 3S. Due to the frictional force caused by this pressing, the element pressing surface 41d and the inner peripheral surface 35d of the housing can rotate integrally without relative displacement.

[0107] The output member 3S receives torque from the input member 2S via the element 4. The output member 3S has a housing portion 35S and an output shaft portion 31S.

[0108] The shape of the housing portion 35S is a thin-walled cylinder. The axis of the housing portion 35S overlaps with the axis of the input member 2S. The housing portion 35S houses the element 4. The housing portion 35S has a housing outer peripheral surface 35a, an input-side main surface 35b, an output-side main surface 35c, a housing inner peripheral surface 35d, and a housing bottom surface 35e. The housing outer peripheral surface 35a is rotatable with respect to the inner peripheral surface of the case hole 11H in the clutch case 11. For example, a slight gap may be formed between the housing outer peripheral surface 35a and the inner peripheral surface of the case hole 11H. The input-side main surface 35b faces the input shaft-side bearing 122. The output-side main surface 35c faces the output shaft-side bearing 123.

[0109] The inner peripheral surface 35d of the housing and the bottom surface 35e of the housing form a space for accommodating the element 4. The inner peripheral surface 35d of the housing is pressed against by the element 4 when torque is input from the input member 2S. The inner peripheral surface 35d of the housing faces the element pressing surface 41d of the element 4.

[0110] The shape of the output shaft portion 31S is cylindrical. The output shaft portion 31S has an outer peripheral surface 31a of the output shaft portion and a main surface 31b of the output shaft portion. The axis of the output shaft portion 31S overlaps with the axis of the housing portion 35S. An output shaft side bearing 123 is provided on the outer peripheral surface 31a of the output shaft portion. That is, the output member 3S including the output shaft portion 31S is rotatably attached to the clutch case 11. The main surface 31b of the output shaft portion is common with the aforementioned bottom surface 35e of the housing.

[0111] [Explanation of the operation of the clutch device Part 1 (When torque is input to the input member 2S)] When torque is input from the input member 2S, as shown in Fig. 15, the input latching portion 22S inserted between the first and second element convex portions 42A and 42B rotates about the rotation axis A (see the arrow CWa in Fig. 15). Due to this rotation, the input latching portion 22S exerts a force F2T on the first and second element convex portions 42A and 42B. By the force F2T, the upper first element main body portion 41A in Fig. 15 moves upward, and by the force F2T, the lower second element main body portion 41B in Fig. 15 moves downward. That is, the first element main body portion 41A and the second element main body portion 41B move away from each other. In the neutral state, the force applied from the element 4 to the housing portion 35S was zero, but due to the operation of the first and second element main body portions 41A and 41B moving away from each other, a force F3T is generated from the element 4 to the housing portion 35S. This force F3T generates a frictional force between the element pressing surface 41d of the element 4 and the inner peripheral surface 35d of the housing of the output member 3S. Since the coupling torque caused by the frictional force is equal to the torque input from the input member 2S, the element 4 does not rotate relative to the housing portion 35S. That is, when the element 4 rotates in response to the rotation of the input member 2S (arrow CWa), the housing portion 35S also rotates together with the element 4 (arrow CWb).

[0112] [Explanation of the operation of the clutch device Part 2 (when torque is reversely input to the output member 3S)] When there is no input of torque from the input member 2S and no input of torque from the output member 3S, and it is in a neutral state, it may be considered that no substantial force acts between the element pressing surface 41d and the inner peripheral surface 35d of the housing. Even when there is an input of torque from the output member 3S, it may be considered that no substantial force acts. In a state where no substantial force acts, it can be considered that no frictional force substantially occurs between the element pressing surface 41d of the element 4 and the inner peripheral surface 35d of the output member 3S. Then, the output member 3S is in a state where relative rotational movement with respect to the element 4 is permitted. As shown in FIG. 16, when the output member 3S rotates (reverse input), the housing portion 35S of the output member 3S can rotate relative to the element 4. That is, since the element 4 does not rotate in accordance with the rotation of the housing portion 35S, the reverse input torque is blocked.

[0113] [Function and effect] The clutch device 1S of the second embodiment includes an input member 2S that is coaxial with the rotation axis A, has a flat cross-sectional shape perpendicular to the rotation axis A, and includes an input latching portion 22S extending along the rotation axis A; an output member 3S that is arranged coaxially with the rotation axis A and includes an inner peripheral surface 35d of the housing; and an element 4 that is arranged coaxially with the rotation axis A and includes an element latching surface 42f facing the input latching portion 22S and an element pressing surface 41d facing the inner peripheral surface 35d of the housing. The output member 3S houses the element 4. The element 4 includes an element pressing surface 41d and an element latching surface 42f respectively, and a first element piece portion 40A and a second element piece portion 40B arranged with the input latching portion 22S sandwiched therebetween so that the element latching surface 42f faces the input latching portion 22S, and a portion continuous with the first element piece portion 40A and a portion continuous with the second element piece portion 40B, and element spring portions 43A and 43B arranged between the first element piece portion 40A and the second element piece portion 40B, and is an integrally molded product.

[0114] The clutch device 1S allows the transmission of torque from the input member 2S to the output member 3S and blocks the reverse input of torque from the output member 3S to the input member 2S. The element 4 for performing the function of transmitting torque and the function of blocking the reverse input of torque is configured as an integral part including first and second element piece portions 40A and 40B and first and second element spring portions 43A and 43B. Therefore, the above-described clutch device 1S can be easily manufactured because the number of parts is small.

[0115] In short, the clutch device 1S of the second embodiment, which is a free type, is composed of three parts: an input member 2S, an output member 3S, and an element 4. The output member 3S in the lock-type clutch device 1S is used as the input member 2S. And the element 4 (engager) provided with first and second element spring portions 43A and 43B (first and second engaging element elastic portions) is configured to sandwich the input member 2S in advance. Further, it is configured so that no preload is generated between the element 4 and the housing portion 35S of the output member 3S. When the input member 2S is rotated, the element 4 is expanded, so the element 4 contacts the housing portion 35S of the output member 3S. As a result, the torque of the input member 2S is transmitted to the output side through the housing portion 35S of the output member 3S. The point that the timing at which torque transmission becomes possible can be controlled according to the degree of the gap between the input latching portion 22S of the element 4 and the first and second element piece portions 40A and 40B when in the neutral state is the same as that of the lock type.

[0116] The free-type torque control clutch device 1S of the second embodiment is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention. The free-type clutch device 1S of the second embodiment can also adopt the configurations of Modifications 6 to 9.

[0117] [Modification 6] <Structure of Modification 6> As shown in Fig. 17(a), the clutch device 1E of Modification 6 includes an element 4E and an output member 3E. In a state where the element 4E is disposed in the housing portion 35E of the output member 3E, the distance from the end portion 43a1 of the first beam portion 43a to the end portion 43b1 of the second beam portion 43b is the first distance L1E. The first distance L1E when the element 4E is disposed in the housing portion 35E is shorter than the second distance L2 (see Fig. 5(b)) when the element 4E is not disposed in the housing portion 35E.

[0118] <Relationship between the housing and preloading in Modification 6> When in the neutral state, the element spring portions 43A and 43B of the clutch device 1E of Modification 6 generate a preloading force F3N that presses the first and second element piece portions 40A and 40B against the housing portion 35E.

[0119] <Relationship between the output latching portion and the clamping force in Modification 6> When in the neutral state, the clutch device 1E of Modification 6 has a gap formed between the input latching portion 22E and the first element piece portion 40A, and between the output latching portion 32A and the second element piece portion 40B. More specifically, the clutch device 1E of Modification 6 has a predetermined gap formed between the main surface 42a of the element convex portion and the main surface 32a of the output latching portion. The input latching portion 22E of the clutch device 1E of Modification 6 does not receive the clamping force F1N from the first and second element piece portions 40A and 40B.

[0120] <Operation and effect of Modification 6> In the clutch device 1E of Modification 6, the first and second element piece portions 40A and 40B are pressed against the housing portion 35E of the output member 3E by the rotation of the input latching portion 22E. As a result, a force F3T (see FIG. 7) caused by the rotation of the input latching portion 22E is added to the preload F3N. Therefore, since the frictional force based on the resultant force of the preload F3N and the force F3T acts between the output member 3E and the element 4E, the clutch device 1E of Modification 6 can transmit the torque from the input side to the output side. Further, when there is reverse input of torque from the output side, the output member 3E rotates while slipping with respect to the element 4E. That is, the clutch device 1E of Modification 6 can attenuate the torque from the output side and transmit it to the input side. The degree of torque attenuation can be determined by the preload F3N in the neutral state.

[0121] [Modification 7] <Structure of Modification 7> As shown in FIG. 17(b), the clutch device 1G of Modification 7 includes an element 4G and an output member 3G. In a state where the element 4G is disposed in the housing portion 35G of the output member 3G, the distance from the end portion 43a1 of the first beam portion 43a to the end portion 43b1 of the second beam portion 43b is the first distance L1G. The first distance L1G when the element 4G is disposed in the housing portion 35G is shorter than the second distance L2 (see FIG. 5(b)) when the element 4G is not disposed in the housing portion 35G.

[0122] <Relationship between the housing and the preload in Modification 7> Similar to the clutch device 1E of Modification 6, the element spring portions 43A and 43B of the clutch device 1G of Modification 7 generate a preload F3N that presses the first and second element piece portions 40A and 40B against the housing portion 35G in the neutral state.

[0123] <Relationship between the output latching portion and the clamping force in Modification 7> Unlike the clutch device 1E of Modification 6, when the clutch device 1G of Modification 7 is in the neutral state, no gap is formed between the input latching portion 22G and the first element piece portion 40A, and between the output latching portion 32A and the second element piece portion 40B. More specifically, the main surface 42a of the element convex portion is pressed against the main surface 32a of the output latching portion. According to this configuration, the input latching portion 22G receives the clamping force F1N from the first and second element piece portions 40A and 40B.

[0124] <Effect of Modification 7> Similar to the clutch device 1E of Modification 6, the clutch device 1G of Modification 7 can transmit torque from the input side to the output side. Furthermore, according to the configuration of Modification 7, the responsiveness to the input of torque from the input side can be enhanced. Furthermore, similar to the clutch device 1E of Modification 6, the clutch device 1G of Modification 7 can attenuate the torque from the output side and transmit it to the input side. The degree of torque attenuation can be determined by the preload F3N when in the neutral state.

[0125] [Modification 8] <Structure of Modification 8> As shown in FIG. 18(a), the clutch device 1H of Modification 8 includes an element 4H and an output member 3H. When the element 4H is disposed in the housing portion 35H of the output member 3H, the distance from the end 43a1 of the first beam portion 43a to the end 43b1 of the second beam portion 43b is the first distance L1H. The first distance L1H when the element 4H is disposed in the housing portion 35H is longer than the second distance L2 (see FIG. 5(b)) when the element 4H is not disposed in the housing portion 35H. This is because an input latching portion 22H having a thickness longer than the second distance L2 is inserted between the first and second element piece portions 40A and 40B.

[0126] <Relationship between the housing and the preload in Modification 8> In the clutch device 1H of Modification 8, the inner diameter of the housing portion 35H is slightly larger than the outer diameter of the element 4H into which the input engaging portion 22H is inserted. The element spring portions 43A and 43B of the clutch device 1H of Modification 8 do not generate a preload F3N that presses the first and second element piece portions 40A and 40B against the housing portion 35H when in the neutral state.

[0127] <Relationship between the output engaging portion and the clamping force in Modification 8> In the clutch device 1H of Modification 8, when in the neutral state, no gap is formed between the input engaging portion 22H and the first element piece portion 40A, and between the input engaging portion 22H and the second element piece portion 40B. More specifically, the main surface 42a of the element convex portion of the clutch device 1H of Modification 8 is pressed against the main surface 22a of the input engagement. According to this configuration, the input engaging portion 22H of the clutch device 1H of Modification 8 receives a clamping force F1N from the first and second element piece portions 40A and 40B.

[0128] <Operation and effect of Modification 8> Similar to the clutch device 1E of Modification 6, the clutch device 1H of Modification 8 can transmit torque from the input side to the output side. Furthermore, the clutch device 1H of Modification 8 can enhance the responsiveness to the input of torque from the input side. Also, when there is reverse input of torque from the output side, the output member 3H of the clutch device 1H of Modification 8 idles with respect to the element 4H. That is, the clutch device 1H of Modification 8 can block the transmission of torque from the output side to the input side.

[0129] [Modification 9] <Structure of Modification 9> As shown in FIG. 18(b), the clutch device 1K of Modification 9 includes an element 4K and an output member 3K. In a state where the element 4K is disposed in the housing portion 35K of the output member 3K, the distance from the end portion 43a1 of the first beam portion 43a to the end portion 43b1 of the second beam portion 43b is a first distance L1K. The first distance L1K when the element 4K is disposed in the housing portion 35K is longer than a second distance L2 (see FIG. 5(b)) when the element 4K is not disposed in the housing portion 35K. This is because an input latching portion 22K having a thickness longer than the second distance L2 is inserted between the first and second element pieces 40A and 40B.

[0130] <Relationship between the housing and preload in Modification 9> Similar to the clutch device 1E of Modification 6, the element spring portions 43A and 43B of the clutch device 1K of Modification 9 generate a preload F3N that presses the first and second element pieces 40A and 40B against the housing portion 35K when in the neutral state.

[0131] <Relationship between the output latching portion and the clamping force in Modification 9> When the clutch device 1K of Modification 9 is in the neutral state, no gaps are formed between the input latching portion 22K and the first element piece 40A, and between the input latching portion 22K and the second element piece 40B. More specifically, the main surface 42a of the element convex portion is pressed against the main surface 22a of the input latching portion. According to this configuration, the input latching portion 22K of the clutch device 1K of Modification 9 receives a clamping force F1N from the first and second element pieces 40A and 40B.

[0132] <Operational effects of Modification 9> The clutch device 1K of Modification 9 can transmit the torque from the input side to the output side, similarly to the clutch device 1E of Modification 6. Further, the clutch device 1K of Modification 9 can enhance the responsiveness to the input of the torque from the input side. Further, the clutch device 1K of Modification 9 can attenuate the torque from the output side and transmit it to the input side, similarly to the clutch device 1E of Modification 6. The degree of torque attenuation can be determined by the preload F3N in the neutral state.

[0133] This disclosure includes the following configurations.

[0134] This disclosure includes: [1] "an input member including a pair of input engaging portions provided so as to sandwich a rotation axis and extending along the rotation axis, an output member coaxial with the rotation axis, having a flat cross-sectional shape orthogonal to the rotation axis, and including an output engaging portion extending along the rotation axis, an engaging element into which the pair of input engaging portions are inserted so as to sandwich the rotation axis, and capable of sandwiching the output engaging portion between the inserted pair of input engaging portions, a pressed member including a pressed surface facing the engaging element and housing the engaging element, and comprising, the engaging element includes an engaging element pressing surface facing the pressed surface and an input engaging hole into which the input engaging portion is inserted, and includes a first engaging element piece portion and a second engaging element piece portion arranged with the output member therebetween, and a portion continuous with the first engaging element piece portion and a portion continuous with the second engaging element piece portion, and an engaging element elastic portion arranged between the first engaging element piece portion and the second engaging element piece portion, and is an integrally molded product, a torque control clutch."

[0135] This disclosure includes: [2] "the first engaging element piece portion includes a first engaging element piece portion main surface extending along the direction of the rotation axis, and a first engaging element piece portion side surface extending along the direction of the rotation axis and facing a direction different from that of the first engaging element piece portion main surface, The second engaging piece portion extends along the direction of the rotation axis and includes a second engaging piece portion main surface facing the main surface of the first engaging piece portion, and a second engaging piece portion side surface extending along the direction of the rotation axis and facing the same direction as the side surface of the first engaging piece portion. The output latching portion is disposed between the main surface of the first engaging piece portion and the main surface of the second engaging piece portion. The first end portion of the engaging elastic portion is continuous with the side surface of the first engaging piece portion. The torque control clutch according to [1] above, wherein the second end portion of the engaging elastic portion is continuous with the side surface of the second engaging piece portion.

[0136] This disclosure is [3] "The first engaging piece portion includes a first engaging piece portion main surface extending along the direction of the rotation axis. The second engaging piece portion extends along the direction of the rotation axis and includes a second engaging piece portion main surface facing the main surface of the first engaging piece portion. The output latching portion is disposed between the main surface of the first engaging piece portion and the main surface of the second engaging piece portion. The first end portion of the engaging elastic portion is continuous with the main surface of the first engaging piece portion. The torque control clutch according to [1] above, wherein the second end portion of the engaging elastic portion is continuous with the main surface of the second engaging piece portion.

[0137] This disclosure is [4] "When the engaging member is in a state of being housed in the pressed member, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is a first distance. When the engaging member is not housed in the pressed member and the engaging elastic portion does not generate an elastic force, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is a second distance. The torque control clutch according to any one of [1] to [3] above, wherein the first distance is equal to the second distance.

[0138] The present disclosure is as follows: [5] "When the engaging member is accommodated in the pressed member, the distance from the portion continuous with the first engaging member piece portion to the portion continuous with the second engaging member piece portion is a first distance, When the engaging member is not accommodated in the pressed member, and when the engaging member elastic portion does not generate an elastic force, the distance from the portion continuous with the first engaging member piece portion to the portion continuous with the second engaging member piece portion is a second distance, The first distance is shorter than the second distance, and the torque control clutch according to any one of the above [1] to [3]."

[0139] The present disclosure is as follows: [6] "When the engaging member is accommodated in the pressed member, the distance from the portion continuous with the first engaging member piece portion to the portion continuous with the second engaging member piece portion is a first distance, When the engaging member is not accommodated in the pressed member, and when the engaging member elastic portion does not generate an elastic force, the distance from the portion continuous with the first engaging member piece portion to the portion continuous with the second engaging member piece portion is a second distance, The first distance is longer than the second distance, and the torque control clutch according to any one of the above [1] to [3]."

[0140] The present disclosure is as follows: [7] "The engaging member pressing surface facing the pressed surface includes a contact portion in contact with the pressed surface and a non-contact portion not in contact with the pressed surface, and the torque control clutch according to any one of the above [1] to [6]."

[0141] The present disclosure is as follows: [8] "The engaging member is an integrally formed product made of a metal material, and the torque control clutch according to any one of the above [1] to [7]."

[0142] The present disclosure is as follows: [9] "The engaging member is an integrally formed product made of a resin material, and the torque control clutch according to any one of the above [1] to [7]."

[0143] The present disclosure is "

[10] The engagement member is an integrally formed product including the engagement member elastic portion formed of a metal material, and the first engagement member piece portion and the second engagement member piece portion formed of a resin material, and is the torque control clutch according to any one of [1] to [7] above."

[0144] The present disclosure is "

[11] The engagement member is an integrally formed product including the engagement member elastic portion formed of a resin material, and the first engagement member piece portion and the second engagement member piece portion formed of a metal material, and is the torque control clutch according to any one of [1] to [7] above."

[0145] The present disclosure is "

[12] An input member that is coaxial with the rotation axis, includes an input latching portion having a flat cross-sectional shape orthogonal to the rotation axis and extending along the rotation axis, an output member arranged coaxially with the rotation axis and including a surface to be pressed, an engagement member arranged coaxially with the rotation axis and including an engagement member latching surface facing the input latching portion and an engagement member pressing surface facing the surface to be pressed, and the output member houses the engagement member, the engagement member includes the engagement member pressing surface and the engagement member latching surface respectively, and includes a first engagement member piece portion and a second engagement member piece portion arranged with the input latching portion sandwiched therebetween so that the engagement member latching surface faces the input latching portion, and a portion continuous with the first engagement member piece portion and a portion continuous with the second engagement member piece portion, and is an integrally formed product having an engagement member elastic portion arranged between the first engagement member piece portion and the second engagement member piece portion, and is a torque control clutch."

[0146] The present disclosure is "

[13] The first engagement member piece portion includes a first engagement member piece portion main surface extending along the direction of the rotation axis, and a first engagement member piece portion side surface extending along the direction of the rotation axis and facing a direction different from that of the first engagement member piece portion main surface, The second engaging piece portion extends along the direction of the rotation axis and includes a second engaging piece portion main surface facing the first engaging piece portion main surface, and a second engaging piece portion side surface extending along the direction of the rotation axis and facing the same direction as the first engaging piece portion side surface. The input latching portion is disposed between the first engaging piece portion main surface and the second engaging piece portion main surface. The first end of the engaging elastic portion is continuous with the first engaging piece portion side surface. The torque control clutch according to

[12] above, wherein the second end of the engaging elastic portion is continuous with the second engaging piece portion side surface.

[0147] The present disclosure is

[14] "The first engaging piece portion includes a first engaging piece portion main surface extending along the direction of the rotation axis, The second engaging piece portion extends along the direction of the rotation axis and includes a second engaging piece portion main surface facing the first engaging piece portion main surface, The input latching portion is disposed between the first engaging piece portion main surface and the second engaging piece portion main surface. The first end of the engaging elastic portion is continuous with the first engaging piece portion main surface. The torque control clutch according to

[12] above, wherein the second end of the engaging elastic portion is continuous with the second engaging piece portion main surface.

[0148] The present disclosure is

[15] "When the engaging member is accommodated in the output member, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is a first distance, When the engaging member is not accommodated in the output member, the distance from the portion continuous with the first engaging piece portion when the engaging elastic portion does not generate an elastic force to the portion continuous with the second engaging piece portion is a second distance, The torque control clutch according to any one of

[12] to

[14] above, wherein the first distance is equal to the second distance.

[0149] The present disclosure is "

[16] When the engaging member is accommodated in the output member, the distance from the portion continuous with the first engaging member piece to the portion continuous with the second engaging member piece is a first distance, When the engaging member is not accommodated in the output member, the distance from the portion continuous with the first engaging member piece when the engaging member elastic portion does not generate an elastic force to the portion continuous with the second engaging member piece is a second distance, The first distance is shorter than the second distance, and the torque control clutch according to any one of

[12] to

[14] above."

[0150] The present disclosure is "

[17] When the engaging member is accommodated in the output member, the distance from the portion continuous with the first engaging member piece to the portion continuous with the second engaging member piece is a first distance, When the engaging member is not accommodated in the output member, the distance from the portion continuous with the first engaging member piece when the engaging member elastic portion does not generate an elastic force to the portion continuous with the second engaging member piece is a second distance, The first distance is longer than the second distance, and the torque control clutch according to any one of

[12] to

[14] above."

[0151] The present disclosure is "

[18] The engaging member pressing surface facing the pressed surface includes a contact portion in contact with the pressed surface and a non-contact portion not in contact with the pressed surface, and the torque control clutch according to any one of

[12] to

[17] above."

[0152] The present disclosure is "

[19] The engaging member is an integrally formed product made of a metal material, and the torque control clutch according to any one of

[12] to

[18] above."

[0153] The present disclosure is "

[20] The engaging member is an integrally formed product made of a resin material, and the torque control clutch according to any one of

[12] to

[18] above."

[0154] The present disclosure is "

[21] The engagement element is an integrally formed product including the engagement element elastic part formed of a metal material, the first engagement element piece part and the second engagement element piece part formed of a resin material, and is the torque control clutch according to any one of

[12] to

[18] above."

[0155] The present disclosure is "

[22] The engagement element is an integrally formed product including the engagement element elastic part formed of a resin material, the first engagement element piece part and the second engagement element piece part formed of a metal material, and is the torque control clutch according to any one of

[12] to

[18] above."

Explanation of Signs

[0156] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1K, 1S... clutch device, 2, 2S... input member, 3, 3E, 3G, 3H, 3K, 3S... output member, 4, 4A, 4B, 4C, 4D, 4E, 4F, 4G, 4H, 4K... element (engager), 5, 5A, 5B, 5C, 5D... housing (pressed member), 11... clutch case, 12, 12S... clutch unit, 21, 21S... input shaft portion, 22A... first input latching portion, 22B... second input latching portion, 22E, 22G, 22H, 22K, 22S... input latching portion, 23... input shaft portion flange, 31, 31S... output shaft portion, 32, 32A, 32B, 32C, 32D... output latching portion, 33... output shaft portion flange, 35E, 35G, 35H, 35K, 35S... housing portion, 40A, 40FA... first element piece portion (first engager piece portion), 40B, 40FB... second element piece portion (second engager piece portion), 41A, 41F1... first element main body portion, 41B, 41F2... second element main body portion, 41d... element pressing surface (engager pressing surface), 41d1... contact portion, 41d2... non-contact portion, 42A, 42F1... first element convex portion, 42B, 42F2... second element convex portion, 43A, 44F1... first element spring portion (engager elastic portion), 43B, 44F2... second element spring portion (engager elastic portion), 51d... housing inner peripheral surface (pressed surface), 121, 121S... clutch module, 122... input shaft side bearing, 123... output shaft side bearing, A... axis of rotation, F1N... clamping force, F3N... preload, L1, L1A, L1B, L1C, L1D, L1E, L1G, L1H, L1K... first distance, L2... second distance.

Claims

1. An input member provided so as to sandwich a rotation axis, the input member including a pair of input latching portions extending along the rotation axis; An output member coaxial with the rotation axis, the output member including an output latching portion having a flat cross-sectional shape orthogonal to the rotation axis and extending along the rotation axis; An engaging element into which the pair of input latching portions are inserted so as to sandwich the rotation axis, and which can sandwich the output latching portion between the inserted pair of input latching portions; A pressed member including a pressed surface facing the engaging element and housing the engaging element; Comprising; The engaging element includes an engaging element pressing surface facing the pressed surface and an input latching hole into which the input latching portion is inserted, and includes a first engaging element piece portion and a second engaging element piece portion disposed with the output member therebetween, and includes a portion continuous with the first engaging element piece portion and a portion continuous with the second engaging element piece portion, and has an engaging element elastic portion disposed between the first engaging element piece portion and the second engaging element piece portion, and is an integrally molded product, a torque control clutch.

2. The first engaging element piece portion includes a first engaging element piece portion main surface extending along the direction of the rotation axis, and a first engaging element piece portion side surface extending along the direction of the rotation axis and facing a direction different from the first engaging element piece portion main surface; The second engaging element piece portion includes a second engaging element piece portion main surface extending along the direction of the rotation axis and facing the first engaging element piece portion main surface, and a second engaging element piece portion side surface extending along the direction of the rotation axis and facing the same direction as the first engaging element piece portion side surface; The output latching portion is disposed between the first engaging element piece portion main surface and the second engaging element piece portion main surface; A first end portion of the engaging element elastic portion is continuous with the first engaging element piece portion side surface; The torque control clutch according to claim 1, wherein a second end portion of the engaging element elastic portion is continuous with the second engaging element piece portion side surface.

3. The first engaging element piece portion includes a first engaging element piece portion main surface extending along the direction of the rotation axis; The second engaging element piece portion includes a second engaging element piece portion main surface extending along the direction of the rotation axis and facing the first engaging element piece portion main surface; The output latching portion is disposed between the first engaging element piece portion main surface and the second engaging element piece portion main surface; A first end portion of the engaging element elastic portion is continuous with the first engaging element piece portion main surface; The torque control clutch according to claim 1, wherein a second end portion of the engagement elastic portion is continuous with a main surface of the second engagement piece portion.

4. When the engagement member is accommodated in the pressed member, a distance from a portion continuous with the first engagement piece portion to a portion continuous with the second engagement piece portion is a first distance, When the engagement member is not accommodated in the pressed member, a distance from a portion continuous with the first engagement piece portion when the engagement elastic portion does not generate an elastic force to a portion continuous with the second engagement piece portion is a second distance, The torque control clutch according to any one of claims 1 to 3, wherein the first distance is equal to the second distance.

5. When the engagement member is accommodated in the pressed member, a distance from a portion continuous with the first engagement piece portion to a portion continuous with the second engagement piece portion is a first distance, When the engagement member is not accommodated in the pressed member, a distance from a portion continuous with the first engagement piece portion when the engagement elastic portion does not generate an elastic force to a portion continuous with the second engagement piece portion is a second distance, The torque control clutch according to any one of claims 1 to 3, wherein the first distance is shorter than the second distance.

6. When the engagement member is accommodated in the pressed member, a distance from a portion continuous with the first engagement piece portion to a portion continuous with the second engagement piece portion is a first distance, When the engagement member is not accommodated in the pressed member, a distance from a portion continuous with the first engagement piece portion when the engagement elastic portion does not generate an elastic force to a portion continuous with the second engagement piece portion is a second distance, The torque control clutch according to any one of claims 1 to 3, wherein the first distance is longer than the second distance.

7. An input member that is coaxial with a rotation axis, includes an input latching portion having a flat cross-sectional shape orthogonal to the rotation axis and extending along the rotation axis, An output member that is coaxially arranged with respect to the rotation axis and includes a pressed surface, An engagement member that is coaxially arranged with respect to the rotation axis and includes an engagement latching surface facing the input latching portion and an engagement pressing surface facing the pressed surface, and The output member accommodates the engagement member. The engaging element includes an engaging element pressing surface and an engaging element latching surface, and is an integrally formed product having a first engaging element piece portion and a second engaging element piece portion that sandwich the input latching portion such that the engaging element latching surface faces the input latching portion, and includes a portion continuous with the first engaging element piece portion and a portion continuous with the second engaging element piece portion, and an engaging element elastic portion disposed between the first engaging element piece portion and the second engaging element piece portion, the torque control clutch.

8. The first engaging element piece portion includes a first engaging element piece main surface extending along the direction of the rotation axis, and a first engaging element piece side surface extending along the direction of the rotation axis and facing a direction different from that of the first engaging element piece main surface. The second engaging element piece portion includes a second engaging element piece main surface extending along the direction of the rotation axis and facing the first engaging element piece main surface, and a second engaging element piece side surface extending along the direction of the rotation axis and facing the same direction as the first engaging element piece side surface. The input latching portion is disposed between the first engaging element piece main surface and the second engaging element piece main surface. The first end of the engaging element elastic portion is continuous with the first engaging element piece side surface. The torque control clutch according to claim 7, wherein the second end of the engaging element elastic portion is continuous with the second engaging element piece side surface.

9. The first engaging element piece portion includes a first engaging element piece main surface extending along the direction of the rotation axis. The second engaging element piece portion includes a second engaging element piece main surface extending along the direction of the rotation axis and facing the first engaging element piece main surface. The input latching portion is disposed between the first engaging element piece main surface and the second engaging element piece main surface. The first end of the engaging element elastic portion is continuous with the first engaging element piece main surface. The torque control clutch according to claim 7, wherein the second end of the engaging element elastic portion is continuous with the second engaging element piece main surface.

10. When the engaging element is accommodated in the output member, the distance from the portion continuous with the first engaging element piece portion to the portion continuous with the second engaging element piece portion is a first distance. When the engaging element is not accommodated in the output member, the distance from the portion continuous with the first engaging element piece portion to the portion continuous with the second engaging element piece portion when the engaging element elastic portion does not generate an elastic force is a second distance. The torque control clutch according to any one of claims 7 to 9, wherein the first distance is equal to the second distance.

11. When the engaging member is accommodated in the output member, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is the first distance. When the engaging member is not accommodated in the output member, the distance from the portion continuous with the first engaging piece portion when the engaging member elastic portion does not generate an elastic force to the portion continuous with the second engaging piece portion is the second distance. The torque control clutch according to any one of claims 7 to 9, wherein the first distance is shorter than the second distance.

12. When the engaging member is accommodated in the output member, the distance from the portion continuous with the first engaging piece portion to the portion continuous with the second engaging piece portion is the first distance. When the engaging member is not accommodated in the output member, the distance from the portion continuous with the first engaging piece portion when the engaging member elastic portion does not generate an elastic force to the portion continuous with the second engaging piece portion is the second distance. The torque control clutch according to any one of claims 7 to 9, wherein the first distance is longer than the second distance.

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