Reverse input cut-off clutch

Abstract

As the output component (4) rotates in a predetermined direction, a pair of pressing surfaces (13) are pressed against the pressed surface (6), and as the input component (3) rotates in a direction opposite to the predetermined direction, the input side engaging portion (9) engages with the input side engaged portion (17). In this state, the contact portion (P) between the input side engaging portion (9) and the input side engaged portion (17) is closed. in ) and the rotation center (O) of the input component (3) in the second direction is greater than the contact portion (P out ) and the rotation center (O) of the output component (4) in the second direction are small. In the locked state or the semi-locked state, the contact portion (C1) between the output side engaging portion (12) and the output side engaged portion (14) is located on the side closer to the rotation center (O) of the output component (4) than the imaginary straight line (L) in the first direction. The imaginary straight line connects the contact portion (C2) between the pressing surface (13) of one of the pair of pressing surfaces (13) and the pressed surface (6) and the rotation center (O) of the output component (4).

Description

Technical Field

[0001] The present invention relates to a reverse input cut-off clutch that transmits a rotational torque input to an input member to an output member, and conversely completely cuts off a rotational torque input in the opposite direction to the output member so that it is not transmitted to the input member, or transmits only a portion of the rotational torque to the input member and cuts off the remaining portion.

[0002] This application claims priority based on Japanese Patent Application No. 2021-211833 filed on December 27, 2021, and Japanese Patent Application No. 2021-185429 filed on November 15, 2021, and incorporates the contents thereof herein. Background Art

[0003] The reverse input cut-off clutch includes an input member connected to an input-side mechanism such as a drive source and an output member connected to an output-side mechanism such as a speed reduction mechanism, and has the following functions: transmitting rotational torque input to the input member to the output member; and, conversely, completely cutting off rotational torque input to the output member in the reverse direction so that it is not transmitted to the input member, or transmitting only a portion of the rotational torque to the input member and cutting off the remaining portion.

[0004] Reverse input cutoff clutches are broadly categorized into locking and free-type clutches, depending on the mechanism used to cut off reverse torque input to the output member. Locking reverse input cutoff clutches have a mechanism that prevents the output member from rotating when reverse torque is input to the output member. Free-type reverse input cutoff clutches, on the other hand, have a mechanism that allows the output member to idle when torque is input to the output member. The decision to use either a locking or free-type reverse input cutoff clutch depends on the application of the device in which the reverse input cutoff clutch is incorporated, among other factors.

[0005] A locking reverse input cut-off clutch is described in International Publication No. 2021 / 054481. The reverse input cut-off clutch described in International Publication No. 2021 / 054481 comprises an input component having a pair of input-side engaging portions, an output component having an output-side engaging portion, a pressed component having a pressed surface, and a coupling component having a coupling component body and a connecting rod component. The coupling component body comprises an output-side engaged portion engaged with the output-side engaging portion and a swing support portion located on a side closer to the pressed surface than the input-side engaging portion. Furthermore, the connecting rod component comprises a first end portion swingably connected to the swing support portion and a second end portion swingably connected to the input-side engaging portion.

[0006] In the reverse input cutting-off clutch described in International Publication No. 2021 / 054481, the above-mentioned engaging part is constructed so that if a rotational torque is input to the above-mentioned input part, the above-mentioned swing support part is pulled by the above-mentioned input side engaging part via the above-mentioned connecting rod part, thereby being displaced away from the above-mentioned pressed surface, and the rotational torque input to the above-mentioned input part is transmitted to the above-mentioned output part by engaging the above-mentioned output side engaging part with the above-mentioned output side engaging part. If a rotational torque is input to the above-mentioned output part in the reverse direction, the above-mentioned pressing surface is pressed against the above-mentioned pressed surface based on the engagement of the above-mentioned output side engaging part with the above-mentioned output side engaged part, so that the above-mentioned pressing surface and the above-mentioned pressed surface are frictionally engaged.

[0007] According to the reverse input disconnecting clutch described in International Publication No. 2021 / 054481, when a rotational torque is input to the input component, it is possible to smoothly switch from a state in which the pressing surface is pressed against the pressed surface (locked state or semi-locked state) to a state in which the pressing surface is separated from the pressed surface (locked release state or semi-locked release state).

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: International Publication No. 2021 / 054481 Summary of the Invention

[0011] Problems to be solved by the invention

[0012] In the reverse input cut-off clutch described in International Publication No. 2021 / 054481, since the engagement member is configured to include an engagement member body and a link member, the number of components is large, component management and assembly costs are high, and manufacturing costs increase.

[0013] In view of the above situation, the object of the present invention is to realize a structure of a reverse input cutting-off clutch, which is configured so that when a rotational torque is input to the input component, it can smoothly switch from a state in which the pressing surface is pressed against the pressed surface (locked state or semi-locked state) to a state in which the pressing surface is separated from the pressed surface (locked release state or semi-locked release state), and can also suppress manufacturing costs.

[0014] Solutions to Problems

[0015] A reverse input cut-off clutch according to one aspect of the present invention includes a pressed member, an input member, an output member, and an engaging member.

[0016] The pressed member has a pressed surface on its inner peripheral surface.

[0017] The input member includes at least one input-side engaging portion disposed radially inward of the pressed surface and is disposed coaxially with the pressed surface.

[0018] The output member includes an output-side engaging portion that is arranged radially inward of the pressed surface and radially inward of the input-side engaging portion, and is coaxially arranged with the pressed surface.

[0019] The above-mentioned engaging part has a pair of pressing surfaces respectively opposite to the above-mentioned pressed surfaces and separated from each other in the circumferential direction, an input side engaged part capable of engaging with the above-mentioned input side engaging part, and an output side engaged part capable of engaging with the above-mentioned output side engaging part, and is configured to be able to move in the far and near direction relative to the above-mentioned pressed surface, i.e., the first direction.

[0020] In addition, if a rotational torque is input to the above-mentioned input component, the above-mentioned input side engaging portion engages with the above-mentioned input side engaged portion, based on which the above-mentioned engaging member is displaced in the first direction away from the above-mentioned pressed surface, and the rotational torque input to the above-mentioned input component is transmitted to the above-mentioned output component by engaging the above-mentioned output side engaged portion with the above-mentioned output side engaging portion, and if a rotational torque is input to the above-mentioned output component in the reverse direction, the above-mentioned output side engaging portion engages with the above-mentioned output side engaged portion, based on which the above-mentioned engaging member presses the above-mentioned pressing surface against the above-mentioned pressed surface, so that the above-mentioned pressing surface and the above-mentioned pressed surface are frictionally engaged.

[0021] In particular, in a reverse input disconnection clutch of one embodiment of the present invention, as the output member rotates in a predetermined direction, the pair of pressing surfaces are pressed against the pressed surfaces, and as the input member rotates in a direction opposite to the predetermined direction, the input side engaging portion engages with the input side engaged portion. In this state, a distance between a contact portion between the input side engaging portion and the input side engaged portion and a rotation center of the input member in a second direction orthogonal to both the first direction and the rotation center of the input member is smaller than a distance between a contact portion between the output side engaging portion and the output side engaged portion and a rotation center of the output member in the second direction.

[0022] In addition, when the rotational torque is input in the reverse direction to the above-mentioned output component and the above-mentioned pair of pressing surfaces are in contact with the above-mentioned pressed surfaces, the contact portion between the above-mentioned output side engaging portion and the above-mentioned output side engaged portion is located on the side closer to the rotation center of the above-mentioned output component than the imaginary straight line in the above-mentioned first direction, wherein the above-mentioned imaginary straight line connects the pressing surface of one of the above-mentioned pair of pressing surfaces with the abutment portion of the above-mentioned pressed surface and the rotation center of the above-mentioned output component.

[0023] The reverse input cut-off clutch according to one aspect of the present invention may include a pair of the engagement elements, and the input member may include a pair of the input-side engagement portions.

[0024] The effects of the invention are as follows.

[0025] According to a reverse input disconnection clutch of one embodiment of the present invention, when a rotational torque is input to the input component, it is possible to smoothly switch from a state in which the pressing surface is pressed against the pressed surface (locked state or semi-locked state) to a state in which the pressing surface is separated from the pressed surface (locked release state or semi-locked release state), and the manufacturing cost can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an end view of the reverse input cutoff clutch according to an example of the embodiment, viewed from the output member side.

[0027] Figure 2 yes Figure 1 II-II sectional view.

[0028] Figure 3 yes Figure 2 XX cross-sectional view.

[0029] Figure 4 The reverse input cut-off clutch of one embodiment is a clutch that shows a state in which a rotational torque is input to an input member. Figure 3 Same picture.

[0030] Figure 5 The reverse input cut-off clutch of one embodiment is a clutch that shows a state in which a rotational torque is input in reverse to an output member. Figure 3 Same picture.

[0031] Figure 6A It is a schematic diagram for explaining the effect of the reverse input cut-off clutch according to an example of the embodiment.

[0032] Figure 6B It is a schematic diagram for explaining the effect of the reverse input cut-off clutch according to an example of the embodiment.

[0033] Figure 6C It is a schematic diagram for explaining the effect of the reverse input cut-off clutch according to an example of the embodiment.

[0034] Figure 7 It is a schematic diagram for explaining the effect of the reverse input cut-off clutch according to an example of the embodiment. DETAILED DESCRIPTION

[0035] use Figures 1 to 6CAn example of an embodiment will be described. Unless otherwise specified, the axial, radial, and circumferential directions refer to the axial, radial, and circumferential directions of the reverse input cut-off clutch 1. In this example, the axial, radial, and circumferential directions of the reverse input cut-off clutch 1 coincide with the axial, radial, and circumferential directions of the input member 3, and also coincide with the axial, radial, and circumferential directions of the output member 4. Furthermore, the axial one-side refers to the input member 3 side ( Figure 2 The other axial side refers to the output component 4 side ( Figure 2 on the left side of the ).

[0036] [Description of the structure of the reverse input cut-off clutch]

[0037] The reverse input cut-off clutch 1 of this example includes a pressed part 2, an input part 3, an output part 4, and a pair of engaging parts 5. The reverse input cut-off clutch 1 has the following reverse input cut-off function: the rotational torque input to the input part 3 is transmitted to the output part 4, and the rotational torque input to the output part 4 in the reverse direction is completely cut off so that it is not transmitted to the input part 3, or only a part of it is transmitted to the input part 3 and the remaining part is cut off. In addition, in the following description, the case where the rotation direction of the input part 3 is counterclockwise and the case where the rotation direction of the output part 4 is clockwise is mainly used as an example, but it is not limited to this. That is, the reverse input cut-off clutch 1 of this example can implement the cut-off (locking action) and the lock release action of the reverse input rotational torque without relying on the rotation direction (torque input direction).

[0038] The pressed member 2 has a cylindrical shape and is fixed to another member (not shown) such as a housing or integrated with another member, thereby restricting its rotation. The pressed member 2 has a pressed surface 6 that is a cylindrical concave surface on its inner circumference.

[0039] The input member 3 is connected to an input-side mechanism such as an electric motor, and receives rotational torque. The input member 3 includes a base plate 7 , an input shaft 8 , and a pair of input-side engaging portions 9 .

[0040] The base plate portion 7 has a substantially circular end surface shape when viewed from the axial direction.

[0041] The input shaft portion 8 protrudes axially from the center of one axial side surface of the base plate portion 7. The input shaft portion 8 includes an input-side connecting portion 10a on one axial side for connecting to the output portion of the input-side mechanism in a torque-transmitting manner. In this example, the input-side connecting portion 10a has a two-sided shape (a two-sided shape) comprising a pair of parallel flat surfaces on the outer circumference. However, the input-side connecting portion 10a may have any shape as long as it connects to the output portion of the input-side mechanism in a torque-transmitting manner.

[0042] The pair of input-side engaging portions 9 have end surfaces that are generally fan-shaped or trapezoidal when viewed axially. They protrude toward the other axial side from two locations on radially opposite sides of the other axial side surface of the base plate portion 7. The pair of input-side engaging portions 9 are separated from each other in the radial direction of the input member 3. Therefore, each input-side engaging portion 9 is positioned on a portion of the other axial side surface of the base plate portion 7 that is radially offset from the rotation center O. Furthermore, each input-side engaging portion 9 has a circumferentially symmetrical shape.

[0043] In this example, the radially inner side surface 9a of each input-side engaging portion 9 is composed of mutually parallel flat surfaces, and the radially outer side surface 9b of each input-side engaging portion 9 has a cylindrical surface contour identical to the outer circumferential surface of the base plate portion 7. Furthermore, a pair of circumferential side surfaces 9c of each input-side engaging portion 9 is composed of flat surfaces that are inclined in a direction that separates from each other as they move radially outward.

[0044] The output member 4 is connected to an output-side mechanism such as a speed reduction mechanism to output rotational torque. The output member 4 is coaxially arranged with the input member 3. In this example, the output member 4 includes an output shaft portion 11 and an output-side engagement portion 12.

[0045] The output shaft portion 11 has a radially outwardly projecting flange 18 at one axial end portion. Furthermore, the output-side connecting portion 10b is provided on the other axial end portion for torque-transmittable connection to the input portion of the output-side mechanism. In this example, the output-side connecting portion 10b has a two-sided, opposing shape comprising a pair of parallel flat surfaces on its outer circumference. However, the output-side connecting portion 10b may have any shape, as long as it is torque-transmittable connection to the input portion of the output-side mechanism.

[0046] The output-side engaging portion 12 has a cam function. That is, the distance from the rotation center O of the output member 4 to the outer peripheral surface of the output-side engaging portion 12 is not constant in the circumferential direction. In this example, the output-side engaging portion 12 has an end surface shape that is roughly rectangular or roughly oblong when viewed from the axial direction, and protrudes axially from the center of the end surface on one side of the output shaft portion 11 toward one side. In other words, the outer peripheral surface of the output-side engaging portion 12 is composed of a pair of parallel flat surfaces 12a and a pair of convex curved surfaces 12b, each of which is partially cylindrical. Therefore, the distance from the rotation center O of the output member 4 to the outer peripheral surface of the output-side engaging portion 12 is not constant throughout the circumferential direction. Furthermore, in this example, the pair of convex curved surfaces 12b are composed of partially cylindrical surfaces centered on the rotation center O of the output member 4.

[0047] The output-side engaging portion 12 is plane-symmetrical with respect to an imaginary plane passing through the rotation center O of the output member 4 and perpendicular to the pair of flat surfaces 12a, and is also plane-symmetrical with respect to an imaginary plane passing through the rotation center O of the output member 4 and parallel to the pair of flat surfaces 12a. Such an output-side engaging portion 12 is disposed between the pair of input-side engaging portions 9.

[0048] The pair of engaging members 5 have end faces that are substantially semicircular when viewed from the axial direction, and are parallel to the flat face 15 described below and are substantially parallel to the flat face 15 described below. Figure 3 It has a symmetrical shape in the direction shown by arrow B).

[0049] The pair of engaging members 5 have a pair of pressing surfaces 13 on their radially outer surfaces, each of which is opposed to the pressed surface 6 and separated from each other in the circumferential direction. Each pressing surface 13 is composed of a convex surface with a curvature radius smaller than that of the pressed surface 6, which is partially cylindrical. In addition, when viewed from the axial direction, the portion of the radially outer side surfaces of the pair of engaging members 5 that deviates from the pair of pressing surfaces 13 in the circumferential direction is located radially inward of an imaginary circle centered on the central axis O of the input component 3 and in contact with the pair of pressing surfaces 13. In other words, when the pair of pressing surfaces 13 are in contact with the pressed surface 6, the portion of the radially outer side surfaces of the pair of engaging members 5 that deviates from the pair of pressing surfaces 13 in the circumferential direction does not abut with the pressed surface 6.

[0050] Each pressing surface 13 preferably has a surface characteristic of having a larger coefficient of friction with the pressed surface 6 than other parts of the engaging member 5. In addition, each pressing surface 13 may be integrally formed with other parts of the engaging member 5, or may be formed on the surface of a friction material fixed to other parts of the engaging member 5 by pasting, bonding, or the like.

[0051] In addition, the pair of engaging members 5 have an output-side engaged portion 14, which is engageable with the output-side engaging portion 12, at the center of the radially inner side surface in the width direction. In this example, the pair of engaging members 5 have a flat surface 15 on the radially inner side surface, and a pair of protrusions 16 protruding radially inward at two locations in the width direction of the flat surface 15. Furthermore, the output-side engaged portion 14 is composed of a portion of the flat surface 15 located between the pair of protrusions 16 in the width direction. Furthermore, in this example, the widthwise dimension of the output-side engaged portion 14 (the distance between the pair of protrusions 16) is larger than the widthwise dimension of the flat surface 12a of the output-side engaging portion 12.

[0052] In addition, the radial direction of the engaging member 5 is Figure 3 The direction indicated by the arrow A is perpendicular to the flat surface 15, and the width direction of the engaging member 5 is Figure 3The direction indicated by the arrow B is parallel to the flat surface 15. In this example, the radial direction of the engaging member 5 is the direction in which the pair of pressing surfaces 13 of the engaging member 5 move relative to the pressed surface 6, which corresponds to the first direction, and the width direction of the engaging member 5 corresponds to the second direction that is orthogonal to both the first direction and the rotation center O of the input member 3.

[0053] Furthermore, the pair of engaging members 5 have input-side engaged portions 17 in the radially intermediate portions of their widthwise central portions, which are capable of engaging with the input-side engaging portion 9. In this example, the input-side engaged portions 17 have a generally arcuate opening when viewed axially and consist of a through-hole extending axially through the radially intermediate portions of the widthwise central portions of the engaging members 5. The input-side engaged portions 17 are sized to allow the input-side engaging portions 9 to be loosely inserted. Therefore, when the input-side engaging portion 9 is inserted inside the input-side engaged portions 17, a gap exists between the input-side engaging portions 9 and the inner surfaces of the input-side engaged portions 17 in both the widthwise and radial directions of the engaging members 5. Consequently, the input-side engaging portion 9 can be displaced relative to the input-side engaged portions 17 (engaging member 5) in the rotational direction of the input component 3, and the input-side engaged portion 17 can be displaced relative to the input-side engaged portions 9 in the radial direction of the engaging member 5. In this example, the input-side engaged portion 17 has a flat surface 17 a parallel to the flat surface portion 15 on the radially inner side surface (the surface facing the radially outer side).

[0054] Furthermore, when implementing the present invention, the input-side engaged portion may be formed by a bottomed hole opening only on one axial side surface of the engaging member, or by a notch opening on the radially outer side surface of the engaging member.

[0055] In the reverse input disconnect clutch 1 of this example, the pair of engaging members 5 are arranged radially inwardly of the pressed member 2 so as to be movable in the radial direction (first direction) of the pair of engaging members 5, with the pair of pressing surfaces 13 of each engaging member 5 facing radially opposite sides and the radially inner side surfaces (flat surface portions 15) of each engaging member 5 facing each other. Furthermore, the pair of input-side engaging portions 9 of the input member 3, arranged on one axial side, are axially inserted into the input-side engaged portions 17 of the pair of engaging members 5, and the output-side engaging portion 12 of the output member 4, arranged on the other axial side, is axially inserted between the pair of output-side engaged portions 14. In other words, the pair of engaging members 5 are arranged so that the output-side engaging portions 12 are sandwiched radially outwardly by the output-side engaged portions 14.

[0056] In addition, when a pair of snap-fit ​​parts 5 are arranged radially inward of the pressed part 2, the inner diameter dimension of the pressed part 2 and the radial dimension of the snap-fit ​​part 5 are limited in such a manner that a gap exists in at least one of the parts between the pressed surface 6 and the pair of pressing surfaces 13, and the parts between the front end surfaces of the protrusions 16.

[0057] (Description of the action of the reverse input cut-off clutch)

[0058] use Figure 4 and Figure 5 The operation of the reverse input cut-off clutch 1 of this example will be described. Figure 4 and Figure 5 The radial gaps between the input member 3 and the output member 4 and the pair of engagement members 5 are shown in an exaggerated manner.

[0059] First, a case where rotational torque is input from the input-side mechanism to the input member 3 will be described.

[0060] If the rotation torque is input to the input member 3, then Figure 4 As shown, the input side engaging portion 9 is located inside the input side engaged portion 17 in the rotation direction of the input member 3 (in Figure 4 In this way, the radially inner side surface 9a of the input side engaging portion 9 presses the flat surface 17a of the input side engaged portion 17 radially inward, causing the pair of engaging members 5 to move in a direction away from the pressed surface 6. In other words, based on the engagement with the input member 3, the pair of engaging members 5 are moved radially inward as a direction of approaching each other (so that the pair of engaging members 5 located at the input side 17a is moved radially inward). Figure 4 The upper side of the engaging member 5 is facing downward, so that the Figure 4 The lower engaging member 5 moves toward the upper side). As a result, the radial inner surfaces of the pair of engaging members 5 move in a direction approaching each other, and the pair of output-side engaged portions 14 clamp the output-side engaging portion 12 of the output member 4 from both radial sides. That is, while the output member 4 is rotated in a manner such that the flat surface 12a of the output-side engaging portion 12 is parallel to the flat surface portion 15 of the engaging member 5, the output-side engaging portion 12 is engaged (abutted) with the pair of output-side engaged portions 14 without shaking. As a result, the rotational torque input to the input member 3 is transmitted to the output member 4 via the pair of engaging members 5 and output from the output member 4. In the reverse input disconnect clutch 1 of this example, if the rotational torque is input to the input member 3, the pair of engaging members 5 are respectively moved in a direction away from the pressed surface 6 regardless of the rotation direction of the input member 3. Then, the rotational torque input to the input member 3 is transmitted to the output member 4 via the pair of engaging members 5.

[0061] Next, a description will be given of a case where the rotational torque is input in reverse from the output-side mechanism to the output member 4 .

[0062] If the rotation torque is inputted to the output component 4 in the reverse direction, Figure 5 As shown, the output side engaging portion 12 is located inside a pair of output side engaged portions 14 in the rotation direction of the output member 4 (in the Figure 5 In this way, the connection portion (corner) between the flat surface 12a and the convex surface 12b on the outer peripheral surface of the output side engaging portion 12 presses the output side engaged portion 14 radially outward, causing the pair of engaging members 5 to move in a direction approaching the pressed surface 6. In other words, based on the engagement with the output member 4, the pair of engaging members 5 are moved radially outward as a direction of separation from each other (so that the output side engaging member 14 is positioned at the outermost position of the output side engaging member 14). Figure 5 The upper side of the engaging member 5 is facing upward, so that the Figure 5 The engaging member 5 on the lower side moves toward the lower side). Thus, the pressing surface 13 of each of the pair of engaging members 5 is frictionally engaged with the pressed surface 6.

[0063] As a result, the rotational torque inputted in the opposite direction to the output member 4 is completely cut off and not transmitted to the input member 3, or only a portion of the rotational torque inputted in the opposite direction to the output member 4 is transmitted to the input member 3, while the remaining portion is cut off. To completely cut off the rotational torque inputted in the opposite direction to the output member 4 and prevent it from being transmitted to the input member 3, the pair of engaging members 5 are supported between the output-side engaging portion 12 and the pressed member 2 so that the pair of pressing surfaces 13 cannot slide (relatively rotate) relative to the pressed surface 6, thereby locking the output member 4. Conversely, to transmit only a portion of the rotational torque inputted in the opposite direction to the output member 4 to the input member 3 and cut off the remaining portion, the pair of engaging members 5 are supported between the output-side engaging portion 12 and the pressed member 2 so that the pair of pressing surfaces 13 slide relative to the pressed surface 6, thereby partially locking the output member 4.

[0064] In the reverse input disconnect clutch 1 of this example, the gaps between the various components are adjusted to enable the above-described operation. Specifically, in the positional relationship where the pair of pressing surfaces 13 of each engaging member 5 contact the pressed surface 6, a gap exists between the radially inner side surface 9a of the input-side engaging portion 9 and the inner surface of the input-side engaged portion 17. This allows the output-side engaged portion 14 to be pressed further toward the pressed surface 6 by the corner of the output-side engaging portion 12. This prevents the radially outward movement of the engaging member 5 from being blocked by the input-side engaging portion 9 when reverse rotational torque is input to the output member 4. Furthermore, after the pair of pressing surfaces 13 contact the pressed surface 6, the surface pressure acting on the contact portion between the pair of pressing surfaces 13 and the pressed surface 6 varies according to the magnitude of the reverse rotational torque input to the output member 4, thereby appropriately locking or partially locking the output member 4.

[0065] In the reverse input cut-off clutch 1 of this example, the sizes and shapes of the pressed member 2 , the input member 3 , the output member 4 , and the pair of engaging members 5 are restricted so as to satisfy the following relationships.

[0066] First, the output member 4 is moved in a predetermined direction (eg Figure 3 The pair of pressing surfaces 13 are pressed against the pressed surface 6, and the input member 3 is rotated in the direction opposite to the predetermined direction (eg, Figure 3 The input side engaging portion 9 is engaged with the input side engaged portion 17 (a portion of the input side engaging portion 9 contacts the input side engaged portion 17). In this state, the contact portion P between the input side engaging portion 9 and the input side engaged portion 17 is in The first distance D1 in the second direction from the rotation center O of the input member 3 is set to be greater than the contact portion P between the output-side engaging portion 12 and the output-side engaged portion 14. out A second distance D2 in the second direction from the rotation center O of the output member 4 is small ( D1 < D2 ).

[0067] And, as Figure 5 As shown, when a rotational torque is inputted in the reverse direction to the output member 4 and the pair of pressing surfaces 13 of each engaging member 5 are in contact with the pressed surface 6 (locked state or semi-locked state), the contact portion C1 between the output-side engaging portion 12 and the output-side engaged portion 14 is located on the side closer to the rotation center O of the output member 4 than the imaginary straight line L in the first direction ( Figure 5 ), wherein the imaginary straight line L connects the abutment portion C2 between the pressing surface 13 of one of the pair of pressing surfaces 13 (the side closer to the contact portion C1 than the rotation center O of the output component 4 in the second direction) and the pressed surface 6 and the rotation center O of the output component 4.

[0068] According to the reverse input cutoff clutch 1 of this example, the axial dimension can be shortened and the number of components can be reduced.

[0069] The reverse input disconnect clutch 1 of this example converts the rotation of the input member 3 and the output member 4 into radial movement of the engaging member 5. Furthermore, by converting the rotation of the input member 3 and the output member 4 into radial movement of the engaging member 5 in this manner, the engaging member 5 engages with the output member 4 located radially inward of the engaging member 5, or presses the engaging member 5 against the pressed member 2 located radially outward of the engaging member 5. Thus, based on the radial movement of the engaging member 5 controlled by the rotation of the input member 3 and the output member 4, the reverse input disconnect clutch 1 of this example can switch between a locked or semi-locked state of the output member 4, which enables transmission of rotational torque from the input member 3 to the output member 4, and a locked or semi-locked state of the output member 4, which prevents or suppresses rotation of the output member 4. This allows the overall axial dimension of the reverse input disconnect clutch 1 to be reduced.

[0070] Moreover, the engaging member 5 is provided with two functions: the function of transmitting the rotational torque input to the input member 3 to the output member 4 and the function of locking or semi-locking the output member 4. Therefore, the number of components of the reverse input cut-off clutch 1 can be suppressed, and the operation can be stabilized compared to the situation in which different components are provided with the function of transmitting the rotational torque and the function of locking or semi-locking. For example, when different components are provided with the function of transmitting the rotational torque and the function of locking or semi-locking, the timing of unlocking or semi-locking unlocking may be staggered with the timing of starting to transmit the rotational torque. In this case, if the rotational torque is input to the output member in the reverse direction during the period from unlocking or semi-locking unlocking to starting to transmit the rotational torque, the output member is locked or semi-locked again. In this example, since the engaging member 5 is provided with two functions: the function of transmitting the rotational torque to the output member 4 and the function of locking or semi-locking the output member 4, such an undesirable situation can be prevented.

[0071] Furthermore, since the direction of the force acting on the engaging member 5 from the input member 3 and the direction of the force acting on the engaging member 5 from the output member 4 are set in opposite directions, the direction of movement of the engaging member 5 can be controlled by limiting the magnitude relationship between the two forces. Therefore, the switching operation of the output member 4 between the locked state or semi-locked state and the locked state or semi-locked state can be performed stably and reliably.

[0072] In the reverse input disconnect clutch 1 of this example, the first distance D1 is made smaller than the second distance D2, and in the locked state or the semi-locked state, the contact portion C1 is located closer to the rotation center O of the output member 4 than the imaginary straight line L in the first direction. Therefore, switching from the locked state or the semi-locked state to the locked release state or the semi-locked release state can be smoothly performed. Figures 6A to 6C The reasons are explained.

[0073] When a rotational torque is input to the input member 3 in the locked state or the semi-locked state of the reverse input cut-off clutch 1 , each engagement element 5 tends to rotate around the contact portion C1 .

[0074] In the case where the first distance D1 is larger than the second distance D2 (D1>D2), if Figure 6B As shown in FIG, if a counterclockwise rotation torque is input to the input member 3, the engaging member 5 tends to rotate counterclockwise around the contact portion C1. Figure 6B As shown by the single-dot chain line in FIG, one of the pair of pressing surfaces 13 is located on the opposite side of the contact portion C1 across the rotation center O of the output member 4 in the second direction ( Figure 6B The pressing surface 13 (on the right side of the input member 3) tends to be strongly pressed and embedded in the pressed surface 6. When the locked state or semi-locked state is switched to the unlocked state or semi-locked state in order to release the embedment of the pressing surface 13 with respect to the pressed surface 6, the rotational torque of the input member 3 increases instantaneously (peak torque is generated).

[0075] Furthermore, when the contact portion C1 is located on the side farther from the rotation center O of the output member 4 than the imaginary straight line L in the first direction, if Figure 6C As shown in FIG, when a counterclockwise rotation torque is input to the input member 3, the engaging member 5 tends to rotate clockwise around the contact portion C1. Figure 6C As shown by the single-dot chain line in FIG, one of the pair of pressing surfaces 13 is located closer to the contact portion C1 than the rotation center O of the output member 4 in the second direction ( Figure 6C The pressing surface 13 (on the left side of the pressing surface 13) tends to be strongly pressed and embedded in the pressed surface 6. When the locked state or semi-locked state is switched to the unlocked state or semi-locked state in order to release the embedment of the pressing surface 13 with respect to the pressed surface 6, the rotational torque of the input member 3 increases instantaneously.

[0076] On the other hand, in the case where the first distance D1 is smaller than the second distance D2 (D1 < D2) as in the reverse input disconnect clutch 1 of this example, and the contact portion C1 is located closer to the rotation center O of the output member 4 than the imaginary straight line L in the first direction, if Figure 6A As shown in FIG, if a counterclockwise rotation torque is input to the input member 3, the engaging member 5 tends to rotate clockwise around the contact portion C1. Figure 6AAs shown by the dot-dash lines r1 and r2 in FIG, neither pressing surface 13 is pressed against the pressed surface 6. Therefore, when switching from the locked or semi-locked state to the unlocked or semi-locked state, the rotational torque of the input member 3 does not increase instantaneously, allowing for smooth switching from the locked or semi-locked state to the unlocked or semi-locked state. Furthermore, since no peak torque is generated, there is no need to unnecessarily increase the maximum output torque of the input-side mechanism, thus preventing unnecessary enlargement of the input-side mechanism.

[0077] According to the reverse input disconnection clutch 1 of this embodiment, it is possible to realize a structure that can smoothly switch from a locked state or a semi-locked state to a locked state or a semi-locked state, unlike the reverse input disconnection clutch described in International Publication No. 2021 / 054481, by providing a structure that does not include a main body of the engaging member and a connecting rod. Therefore, the number of components can be reduced, and the manufacturing cost can be suppressed. In addition, Figures 6A to 6C In the contact part P in and the contact portion C2 are located at the same height in the first direction, but even at the contact portion P in Even when the position of the contact portion C2 in the first direction is different from that of the contact portion C2, the same operational effects as those described above can be achieved.

[0078] Figure 7 It is a schematic diagram for explaining the effect of the reverse input cut-off clutch according to an example of the embodiment. Figure 7 In the figure, the input component 3 is shown to be Figures 6A to 6C The example shown is an example of a case where the rotation is in the opposite direction (ie, clockwise).

[0079] In the above embodiment, the case where the input member 3 rotates counterclockwise in a state where the pair of pressing surfaces 13 are pressed against the pressed surface 6 and the input side engaging portion 9 is engaged with the input side engaged portion 17 is described as an example, but the same effect can be achieved when the input member 3 rotates clockwise. In other words, even in the case Figure 7 The contact portion P between the input side engaging portion 9 and the input side engaged portion 17 as a force point is shown. in Even when it is located to the right of the rotation center O of the output member 4, it is in contact with the contact portion P. in The same as the above embodiment, which is located to the left of the rotation center O of the output member 4, can suppress the occurrence of the insertion and improve the unlocking performance. That is, when the first distance D1 is smaller than the second distance D2 (D1 < D2), and the contact portion C1 is located on the side closer to the rotation center O of the output member 4 than the imaginary straight line L in the first direction, if Figure 7As shown in FIG, if a clockwise rotation torque is input to the input member 3, the engaging member 5 tends to rotate counterclockwise around the contact portion C1. Figure 7 As shown by the dot-dash lines r1 and r2 in the figure, neither pressing surface 13 is pressed against the pressed surface 6. Therefore, when switching from the locked or semi-locked state to the unlocked or semi-locked state, the rotational torque of the input member 3 does not increase instantaneously, allowing for smooth switching from the locked or semi-locked state to the unlocked or semi-locked state. Furthermore, since no peak torque is generated, there is no need to unnecessarily increase the maximum output torque of the input-side mechanism, thus preventing unnecessary enlargement of the input-side mechanism.

[0080] Furthermore, when implementing the reverse input cutoff clutch of the present invention, the number of engagement members can be one or three or more.

[0081] In addition, when implementing the reverse input cut-off clutch of the present invention, the engaging member can also be provided with an elastic member that elastically applies force to the pair of pressing surfaces in the direction toward the pressed surface. The elastic member can be composed of, for example, a torsion coil spring, a leaf spring, etc. In the case where a pair of the above-mentioned engaging members are provided and the elastic member is composed of a torsion coil spring, the protrusion (in this example) provided by the above-mentioned engaging member can also be provided. Figure 1 and Figures 3-5 The protrusion 16 shown is inserted into the end of the torsion coil spring to hold the torsion coil spring.

[0082] The materials of the input component, output component, pressed component, and engaging member are not particularly limited. For example, in addition to metals such as iron alloys, copper alloys, and aluminum alloys, synthetic resins mixed with reinforcing fibers may also be used as needed. Furthermore, the input component, output component, pressed component, and engaging member may be made of the same material or different materials.

[0083] Furthermore, when a rotational torque is input in the reverse direction to the output member, as long as the output member satisfies the locked or semi-locked conditions, lubricating oil can be introduced between the contacting portions of the input member, the output member, the pressed member, and the engaging member. Therefore, for example, at least one of the input member, the output member, the pressed member, and the engaging member can be made of oil-impregnated metal.

[0084] Explanation of symbols

[0085] 1—reverse input cut-off clutch, 2—pressed component, 3—input component, 4—output component, 5—engaging component, 6—pressed surface, 7—base plate portion, 8—input shaft portion, 9—input side engaging portion, 9a—radial inner surface, 9b—radial outer surface, 9c—circumferential side surface, 10a—input side connecting portion, 10b—output side connecting portion, 11—output shaft portion, 12—output side engaging portion, 12a—flat surface, 12b—convex curved surface, 13—pressing surface, 14—output side engaged portion, 15—flat surface portion, 16—convex portion, 17—input side engaged portion, 17a—flat surface, 18—flange portion.

Claims

1. A reverse input cut-off clutch, characterized in that: have: a pressed component having a pressed surface on its inner circumference; an input member having at least one input-side engaging portion disposed radially inward of the pressed surface and disposed coaxially with the pressed surface; an output member having an output-side engaging portion disposed radially inward of the pressed surface and further radially inward than the input-side engaging portion, and disposed coaxially with the pressed surface; and The engaging member comprises a pair of pressing surfaces respectively opposed to the pressed surfaces and separated from each other in the circumferential direction, an input-side engaged portion engageable with the input-side engaging portion, and an output-side engaged portion engageable with the output-side engaging portion, and is configured to be movable in a first direction, i.e., a distance direction relative to the pressed surfaces. When a rotational torque is input to the input component, the input-side engaging portion engages with the input-side engaged portion, and the engaging member is displaced in the first direction away from the pressed surface, so that the output-side engaged portion engages with the output-side engaging portion, thereby transmitting the rotational torque input to the input component to the output component. Furthermore, when a rotational torque is input to the output component in the reverse direction, the output-side engaging portion engages with the output-side engaged portion, and the engaging member presses the pressing surface against the pressed surface, causing the pressing surface and the pressed surface to frictionally engage. As the output member rotates in a predetermined direction, the pair of pressing surfaces are pressed against the pressed surfaces, and as the input member rotates in a direction opposite to the predetermined direction, the input-side engaging portion engages with the input-side engaged portion. In this state, a distance between a contact portion between the input-side engaging portion and the input-side engaged portion and a rotation center of the input member in a second direction perpendicular to both the first direction and the rotation center of the input member is smaller than a distance between a contact portion between the output-side engaging portion and the output-side engaged portion and a rotation center of the output member in the second direction. When a rotational torque is input in the reverse direction to the above-mentioned output component and the above-mentioned pair of pressing surfaces are in contact with the above-mentioned pressed surfaces, the contact portion between the above-mentioned output-side engaging portion and the above-mentioned output-side engaged portion is located on the side closer to the rotation center of the above-mentioned output component than the imaginary straight line in the above-mentioned first direction, wherein the above-mentioned imaginary straight line connects the pressing surface of one of the above-mentioned pair of pressing surfaces with the abutment portion of the above-mentioned pressed surface and the rotation center of the above-mentioned output component.

2. The reverse input cut-off clutch according to claim 1, characterized in that: The pair of engagement pieces is provided, and the input member has a pair of input-side engagement portions.

Images