JP2023094515A - Reverse input cutoff clutch and clutch unit comprising the same - Google Patents

Abstract

To realize a reverse input cutoff clutch with excellent operability.SOLUTION: A reverse input cutoff clutch (one-way clutch 20A) switches between a locked state in which rotation of an output shaft 22 with respect to a stationary member 23 is restricted and an unlocked state in which rotation of the output shaft 22 is permitted, by radially displacing an engaging element 28 fitted into a concave groove 22c of the output shaft 22 depending on whether or not torque T is input to an input member 21. In the reverse input cutoff clutch, a releasing force application unit M for applying releasing force to the engaging element 28 for releasing an engagement state with the stationary member 23 as the torque T is input to the input member 21, is arranged on the inside in a circumferential direction with respect to both end parts of the engaging element 28 in the circumferential direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to a reverse input cutoff clutch and a clutch unit having the same.

As is well known, a reverse input cut-off clutch transmits torque input to an input member to an output member (for example, an output shaft), cuts off reverse input torque input to the output shaft, and receives reverse input torque. It has the function of not transmitting to the member. Some of the reverse input cutoff clutches are of a locking type that locks the output shaft against a stationary member whose rotation is restricted when a reverse input torque is applied. Japanese Patent Laying-Open No. 2014-122647 (Patent Document 1) discloses, for example, a clutch unit incorporated in a seat lifter that adjusts the seat surface height of an automobile seat, and includes a lock type reverse input cutoff clutch. is described.

FIG. 16 shows a vertical cross-sectional view of a reverse input cut-off clutch to which the technical means described in Patent Document 1 is applied in a no-load state. The reverse input cut-off clutch 100 includes an input member 101 to which torque is input, an output shaft 102 as an output member for outputting the torque, an annular stationary member 103 whose rotation is restricted, the output shaft 102 and the stationary member. 103 and a plurality of (three in the illustrated example) engaging elements 104 arranged at intervals in the circumferential direction. It is fitted in a concave groove 102a provided on the output shaft 102. As shown in FIG. Between the groove bottom of the concave groove 102a and the engaging element 104, an elastic member 105 such as a coil spring is interposed in a radially compressed state. Therefore, the engaging element 104 is always urged radially outward by the elastic restoring force of the elastic member 105 .

A serrated tooth surface 103a is formed along the entire circumference of the inner peripheral surface of the stationary member 103, and is formed on the outer peripheral surface of each engaging element 104 when no torque is input to the input member 101. A serrated tooth surface 104a meshes with the tooth surface 103a. In this state, each engaging piece 104 is engaged with the output shaft 102 and the stationary member 103 in the circumferential direction, thereby restricting the rotation of the output shaft 102 with respect to the stationary member 103. Therefore, the reverse input torque input to the output shaft 102 Transmission of T' (see FIG. 17) to the input member 101 is blocked.

The input member 101 is an arc-shaped column interposed between two engaging elements 104 adjacent in the circumferential direction and between the inner peripheral surface (tooth surface 103a) of the stationary member 103 and the outer peripheral surface of the output shaft 102. When torque is input to the input member 101, the column portion 101a engages the engaging element 104 (more specifically, the engaging element 104 on the front side in the rotational direction of the input member 101). On the other hand, it functions as a release force application unit that applies pressure (disengagement force) for releasing the engagement state with the stationary member 103 . That is, as shown in FIG. 17, the torque (torque in the same direction as the reverse input torque T') T input to the input member 101 is arranged adjacently on the front side in the rotational direction of the input member 101 via each column portion 101a. When input (transmitted) to (the inclined surface of) the engaging element 104 , each engaging element 104 is displaced radially inward against the elastic restoring force of the elastic member 105 . As a result, the meshing state between the tooth surface 104a of each engaging element 104 and the tooth surface 103a of the stationary member 103, that is, the circumferentially engaged state between the stationary member 103 and each engaging element 104 is released. , the engaging element 104 and the input member 101 are rotatable in the input direction of the torque T.

When the torque input to the input member 101 disappears, the disengagement force input to the engaging element 104 also disappears. Then, the tooth surface 104a meshes with the tooth surface 103a of the stationary member 103 again (see FIG. 16). This restricts the rotation of the output shaft 102 with respect to the stationary member 103 .

In short, in the above-described reverse input cutoff clutch 100, the radial displacement of the engaging element 104 within the groove 102a of the output shaft 102 results in a locked state in which the rotation of the output shaft 102 is restricted, and a rotation of the output shaft 102. is switched between an unlocked state that allows Therefore, as schematically shown in the enlarged view of FIG. 16, between the peripheral end surfaces of the engaging member 104 and the groove 102a (the fan-shaped groove defining portion 102b defining the groove 102a) facing each other in the circumferential direction is provided with a circumferential clearance δ having a predetermined width in order to ensure smooth radial displacement of the engaging element 104 .

JP 2014-122647 A

In the reverse input interrupting clutch 100 described above, when a reverse input torque T' is input to the output shaft 102 as shown in FIG. , and there is a possibility that the engaging element 104 that receives the rotational force of the output shaft 102 rotates within the groove 102a (tilts with respect to the depth direction of the groove 102a). Torque T in the same direction as the reverse input torque T′ input to the output shaft 102 with the engaging element 104 tilted is input (transmitted) to the engaging element 104 via the column portion 101a. Accordingly, when the disengagement force (pressurizing force for displacing radially inward) is applied to the engaging element 104, the engaging element 104 is also subjected to a rotational force R in the direction of increasing the rotation (inclination). works. In this case, since the engaging element 104 is displaced radially inward while making point contact with the peripheral end surface of the groove defining portion 102b provided on the output shaft 102, abnormal noise is generated. In other words, the torque T to be input to the input member 101 may increase.

Accordingly, the present invention provides a locked state in which the rotation of the output shaft is restricted by radially displacing an engaging member fitted in a groove of the output shaft according to the presence or absence of torque input to the input member, and an output shaft. To realize a reverse input interrupting clutch excellent in operability by making an engaging element smoothly displaceable in a reverse input interrupting clutch switched between an unlocked state in which rotation of a shaft is permitted.

The present invention, which has been devised to achieve the above objects,
An input member to which torque is input, an output shaft capable of outputting torque, a stationary member whose rotation is restricted, and a plurality of engaging elements arranged at intervals in the circumferential direction between the output shaft and the stationary member. with
each engaging element is fitted in a concave groove formed in the output shaft so as to be displaceable in the radial direction;
an elastic member is interposed between the groove bottom of the concave groove and the engaging element in a state of being compressed in a radial direction;
The engaging element receiving the elastic restoring force of the elastic member engages with the stationary member and the output shaft in the circumferential direction, thereby locking the rotation of the output shaft with respect to the stationary member, and the engaging element moves as described above with the torque input to the input member. In a reverse input interrupting clutch in which the engaged state of the engaging element and the stationary member in the circumferential direction is released by displacing radially inward against the elastic restoring force,
A releasing force applying portion that applies a releasing force to the engaging element for releasing the state of engagement with the stationary member in response to torque input to the input member is arranged circumferentially inward of both circumferential direction end portions of the engaging element. It is characterized by

In the conventional reverse input cut-off clutch 100 described with reference to FIGS. The column portion 101a of the input member 101 interposed between the input member 101 and the outer diameter surface of 102 (groove defining portion 102b) functions as a "releasing force applying portion". In such a configuration, the groove defining portion 102b of the output shaft 102 is entirely positioned away from the column portion 101a so that the groove defining portion 102b of the output shaft 102 does not interfere with the column portion 101a of the input member 101 disposed on the outer diameter side thereof. must also be provided on the inner diameter side. Therefore, when a reverse input torque T' is input to the output shaft 102, the contact area between (the recessed groove defining portion 102b of) the output shaft 102 and the engaging element 104 is the inner diameter side area of the peripheral end surface of the engaging element 104. limited (see FIG. 17). Such a structure and a structure in which the engaging element 104 is fitted in the groove 102a of the output shaft 102 so as to be displaceable in the radial direction (a circumferential gap δ is provided between the engaging element 104 and the groove 102a). structure), when a reverse input torque T' is input to the output shaft 102, as shown in FIG. It is considered to be a thing.

On the other hand, in the reverse input clutch according to the present invention, the release force applying portion is arranged circumferentially inside the circumferential direction end portions of the engaging element, that is, within the circumferential direction range of the engaging element. In this case, the input member has a pillar portion (arranged between two engaging members adjacent in the circumferential direction and radially outside the concave groove defining portion of the output shaft) as shown in FIGS. , pillars for pressing the engaging element with the rotation of the input member), the recessed groove defining part is enlarged radially outward compared to the conventional structure, and the engaging element and the recessed groove defining part are separated from each other. Contact length can be increased. As a result, when the recessed groove defining portion comes into contact with the engaging element housed in the recessed groove so as to be displaceable in the radial direction as a reverse input torque is input to the output shaft, the engaging element is displaced from the recessed groove. It is possible to suppress or prevent tilting with respect to the depth direction (radial direction). Therefore, as torque (torque in the same direction as the reverse input torque) is input to the input member, a pressing force for releasing the engagement state of the engaging element with the stationary member is applied from the releasing force applying section. When applied, the engaging element can be smoothly displaced radially inward along the concave groove.

In the above configuration, the releasing force applying section is arranged to apply the releasing force to the engaging element in a region of the engaging element on the front side in the torque input direction from the center of rotation of the engaging element in the recessed groove. is preferred.

In this way, when the engaging element fitted in the concave groove of the output shaft is inclined with respect to the depth direction of the concave groove due to the reverse input torque being input to the output shaft (the engaging element When the torque is input to the input member, the releasing force is applied to the engaging member from the releasing force applying unit even when the input member rotates in the recessed groove), the above inclination (rotation) occurs. can be applied to the engaging element to return the engaging element to the proper posture. Accordingly, when torque is input to the input member, the engaging element can be smoothly displaced radially inward.

The above-described present invention provides a reverse input interrupting clutch in which an input member is provided with a convex portion extending in the axial direction that constitutes the releasing force applying portion, and an engaging member is provided with a hole into which the convex portion is inserted. It can be preferably applied.

The reverse input cut-off clutch according to the present invention can have a displacement limiting portion that limits radially inward displacement of the engaging element before the elastic member reaches a compression limit. As a result, for example, the elastic member is excessively compressed and deformed, thereby losing its original elastic restoring force and smoothly displacing the engaging element radially outward (smoothly displacing the reverse input cut-off clutch from the unlocked state). It is possible to reduce the possibility of problems such as being unable to shift to the locked state. Therefore, the durability and reliability of the reverse input cut-off clutch can be enhanced.

The displacement limiting portion may be provided on the output shaft or may be provided on the engaging element. In any case, the displacement limiting portion may be provided integrally with the base material (the output shaft or the engaging element), or may be configured as a separate member fixed to the base material.

A first clutch portion for controlling transmission and interruption of torque input by lever operation and a second clutch portion comprising a reverse input cutoff clutch according to the present invention are provided, and the output of the first clutch portion (input by lever operation) is provided. The reverse input interrupting clutch according to the present invention is excellent in operability and switches between the locked state and the unlocked state (especially from the locked state to the unlocked state). transition) can be performed smoothly, so it is used in applications where torque is frequently input to the input member while reverse input torque is being input, such as a seat lifter for adjusting the seat height of an automobile seat. can be preferably employed.

As described above, according to the present invention, according to the presence or absence of torque input to the input member, the engaging element fitted in the concave groove of the output shaft is displaced in the radial direction, thereby restricting the rotation of the output shaft. In a reverse input interrupting clutch that switches between a state and an unlocked state in which rotation of an output shaft is permitted, an engaging member can be smoothly displaced, thereby realizing a reverse input interrupting clutch with excellent operability. .

1 is a schematic longitudinal sectional view of a clutch unit including a reverse input cutoff clutch according to one embodiment of the present invention; FIG. 2 is a cross-sectional view taken along line A1-A1 of FIG. 1; FIG. FIG. 2 is a cross-sectional view taken along line A2-A2 of FIG. 1; FIG. 2 is a cross-sectional view taken along line A3-A3 of FIG. 1; 4 is a partially enlarged view of FIG. 3; FIG. FIG. 2 is a schematic perspective view of an input member of the reverse input blocking clutch shown in FIG. 1; FIG. 4 is a partial enlarged view for explaining the operating mode of a second clutch portion composed of a reverse input cut-off clutch, in which (a) shows a state (locked state) in which torque is input to the input member, and (b); The figure shows a state in which the rotation of the input member has progressed slightly from (a) as a result of torque input to the input member, and (c) shows a state in which the rotation of the input member has progressed further than in (b). and (d) shows a state in which the output shaft is rotating. FIG. 8 is a schematic perspective view of an input member of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 6 is a vertical cross-sectional view of a reverse input cutoff clutch according to another embodiment of the present invention; FIG. 10 is a vertical cross-sectional view of a conventional reverse input cutoff clutch in a no-load state; FIG. 17 is a longitudinal sectional view schematically showing a state in which a reverse input torque is input to the output shaft of the reverse input cutoff clutch shown in FIG. 16;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic vertical cross-sectional view of a clutch unit 1 including a reverse input cutoff clutch according to an embodiment of the present invention, and FIGS. A cross-sectional view taken along line A2 and a cross-sectional view taken along line A3-A3 are shown. The clutch unit 1 shown in FIG. 1 is used, for example, by being incorporated in a seat lifter for adjusting the seat surface height of an automobile seat. A second clutch part 20 is provided in which two one-way clutches, which are clutches, are arranged side by side. Hereinafter, the structure and the like of the first clutch portion 10 will be briefly described first, and then the structure and the like of the second clutch portion 20 will be described in detail. In the following description, the terms “axial direction”, “radial direction” and “circumferential direction” used to indicate directionality refer to the axial center of the output shaft 22 of the second clutch portion 20 (clutch unit 1). A direction parallel to X, a radial direction of a circle centered on the axis X, and a circumferential direction of a circle centered on the axis X.

As shown in FIGS. 1 and 2, the first clutch portion 10 includes a side plate 11, an outer ring 12 and an inner ring 13, which are fitted to the outer periphery of the output shaft 22 in a rotatable state about the axis X of the output shaft 22. , a plurality of engaging elements (cylindrical rollers) 14 for transmitting torque input to the outer ring 12 through the side plate 11 to the inner ring 13;

The outer ring 12 has a cylindrical portion having a plurality of cam surfaces 12a formed on the inner peripheral surface thereof at regular intervals in the circumferential direction. The outer ring 12 is connected by appropriate means to a side plate 11 to which an operating lever (not shown) of the seat lifter is attached, and constitutes an input member of the first clutch portion 10 together with the side plate 11 .

An annular retaining member (for example, a washer) 2 that can be axially engaged with the first clutch portion 10 (outer ring 12 ) is fixed to the output shaft 22 . An elastic member (for example, a wave washer) 3 that is compressively deformable in a direction is interposed. This allows the input member of the first clutch portion 10 including the outer ring 12 to rotate smoothly, and prevents the first clutch portion 10 from coming off from the output shaft 22 .

As shown in FIGS. 1 and 2, the inner ring 13 has a cylindrical outer peripheral surface 13a forming a wedge clearance Ga between which the cylindrical rollers 14 are arranged and a cam surface 12a provided on the inner peripheral surface of the outer ring 12. and a flange portion 13c extending radially outward from the end of one axial side of the tubular portion 13b (the left side of the paper surface of FIG. 1; hereinafter referred to as “one axial side”), It integrally has a claw portion 13d extending in one axial direction from the outer peripheral edge portion of the flange portion 13c. A plurality (here, three) of the claw portions 13d are provided at intervals in the circumferential direction, and are recess-shaped cutout portions formed on the outer diameter surface of the concave groove defining portion 22d of the output shaft 22, which will be described later. (See FIGS. 3 and 4). The inner ring 13 having the above structure functions as an output member of the first clutch portion 10 and also functions as an input member 21 of the second clutch portion 20 . Therefore, torque input to the first clutch portion 10 due to lever operation is input (transmitted) to the second clutch portion 20 via the inner ring 13 .

As shown in FIG. 2, the retainer 15 is a tubular member in which a plurality of pocket portions 15a for individually accommodating a plurality of cylindrical rollers 14 are formed at regular intervals in the circumferential direction. The rollers 14 are rotatably held.

The inner centering spring 16 is an elastic member formed by bending a metal wire into a C shape, and is arranged between the retainer 15 and the stationary member 23 of the second clutch portion 20 . When torque is input to the outer ring 12 (the input member of the first clutch portion 10) due to the lever operation, the inner centering spring 16 is expanded due to the rotation of the retainer 15 that rotates following the outer ring 12. An elastic restoring force is accumulated in the inner centering spring 16 . When the torque input to the outer ring 12 ceases, the elastic restoring force accumulated in the inner centering spring 16 is released, and the retainer 15 returns to the neutral position (neutral state).

The outer centering spring 17 is an elastic member formed by bending a metal band plate into a C shape, and is between the outer ring 12 and the stationary member 23 of the second clutch portion 20 and in the radial direction of the inner centering spring 16. placed outside. When the outer ring 12 rotates by inputting torque to the outer ring 12 as the lever is operated, the outer centering spring 17 is expanded with this rotation, and elastic restoring force is accumulated in the outer centering spring 17 . Then, when the torque input to the outer ring 12 disappears, the elastic restoring force accumulated in the outer centering spring 17 is released, and the outer ring 12 returns to the neutral position.

The first clutch portion 10 configured as described above operates as follows. First, when torque is input to the outer ring 12 through the side plate 11 by operating an operation lever (not shown), the cylindrical rollers 14 are engaged with the wedge clearance Ga between the outer ring 12 and the inner ring 13, and the cylindrical rollers 14 Torque is transmitted to the inner ring 13 via , and the inner ring 13 rotates. At this time, elastic restoring force is accumulated in both centering springs 16 and 17 as the outer ring 12 and retainer 15 rotate. When the lever operation is stopped and the torque input to the outer ring 12 ceases, the retainer 15 and the outer ring 12 return to the neutral position due to the elastic restoring force of both the centering springs 16 and 17, while the inner ring 13 returns to the given rotational position. be kept as is. Therefore, the inner ring 13 is inching rotated by operating the lever.

Next, the second clutch portion 20 having a lock type reverse input cutoff clutch according to the embodiment of the present invention will be described. The second clutch portion 20 of the present embodiment is a two-layer structure two-way clutch in which two one-way clutches 20A and 20B, which are locking type reverse input cut-off clutches, are axially arranged side by side.

As shown in FIGS. 1 and 3, one of the two one-way clutches (one-way clutch 20A) is an input member 21 to which torque is input from the first clutch portion 10, and an input member 21 to which torque is input. It is arranged between the output shaft 22 capable of outputting torque, the stationary member 23 whose rotation is restricted, and the output shaft 22 and the stationary member 23 (specifically, the first outer ring 26 which is a component of the stationary member 23). An engaging element 28, an elastic member 30, and pins 31 and 32 are provided. The input member 21 is composed of the inner ring 13 of the first clutch portion 10 as described above.

1 and 4, the other of the two one-way clutches (one-way clutch 20B) has an input member 21 to which torque is input from the first clutch portion 10, and an input member 21 to which torque is input. between the output shaft 22 capable of outputting torque, the stationary member 23 whose rotation is restricted, and the output shaft 22 and the stationary member 23 (specifically, the second outer ring 27 that is a component of the stationary member 23). It has an engaging element 29 and an elastic member 30, and pins 31 and 32, which are arranged. In short, in the second clutch portion 20, the input member 21, the output shaft 22, the stationary member 23 (strictly speaking, a part of the stationary member 23; details will be described later), the elastic member 30, and the pins 31, 32 are combined into two parts. The two one-way clutches 20A and 20B are also used. Although the details will be described later, when the torque T is input to the second clutch portion 20, the engaging element 29 of the one-way clutch 20B moves differently from the engaging element 28 of the one-way clutch 20A. Therefore, when a coil spring is used for the elastic member 30 as in the present embodiment, it is preferable to individually incorporate the coil spring as the elastic member 30 into the one-way clutches 20A and 20B.

As shown in FIGS. 1, 3 and 4, the output shaft 22 of the present embodiment includes a shaft portion 22a having a cylindrical portion 13b of the input member 21 (inner ring 13) fitted on the outer circumference thereof, and an output shaft portion 22a of the output shaft 22. to a rotation transmission target (for example, a gear of an automobile seat lifter), and a fan-shaped concave groove defining portion 22d projecting radially outward from the shaft portion 22a. A plurality (here, three) of the defining portions 22d are provided at intervals in the circumferential direction. An outer diameter surface (outermost diameter surface) of the concave groove defining portion 22 d is arranged close to the inner peripheral surfaces of the first outer ring 26 and the second outer ring 27 . Two recessed groove defining portions 22d that are adjacent in the circumferential direction form a recessed groove 22c that extends in the radial direction and that is open on the outer diameter side and has a constant groove width. Engagers 28 and 29 are fitted in the recessed grooves 22c so as to be arranged side by side in the axial direction.

As shown in FIG. 1, the stationary member 23 is composed of a side plate 24, a first outer ring 26, a second outer ring 27, and a cover 25 which are arranged in order from one axial side to the other side in the axial direction. formed by The first outer ring 26 is a component of the one-way clutch 20A, and the second outer ring 27 is a component of the one-way clutch 20B. Therefore, of the components of the stationary member 23, the side plate 24 and the cover 25 are also used by the two one-way clutches 20A and 20B.

As shown in FIG. 3, the inner peripheral surface of the first outer ring 26 is formed with a serrated tooth surface 26a over the entire circumference. A serrated tooth surface 27a is formed along the entire circumference. The tooth flank 26a formed on the inner peripheral surface of the first outer ring 26 is formed by alternately arranging a plane along the radial direction and an inclined plane forming an acute angle with respect to the plane in the circumferential direction. A tooth surface 27a formed on the inner peripheral surface of the outer ring 27 forms an acute angle with a plane extending in the radial direction, and is inclined in the direction opposite to the inclined surface forming the tooth surface 26a of the first outer ring 26. It is formed by alternately arranging the slanted surfaces in the circumferential direction. In other words, the slanted surface forming the serrated tooth surface 26a and the slanted surface forming the serrated tooth surface 27a are inclined in opposite directions.

The engaging elements 28 and 29 are fitted into the groove 22c so as to be displaceable along the radial direction (the depth direction of the groove 22c of the output shaft 22). Therefore, although detailed illustration is omitted, there is a minute circumferential gap as described with reference to FIG. The outer diameter surface of the engaging element 28 is formed with a sawtoothed tooth surface 28a that meshes with the tooth surface 26a formed on the inner peripheral surface of the first outer ring 26, and the outer diameter surface of the engaging element 29 is formed with a second A saw-toothed tooth surface 29a that meshes with the tooth surface 27a formed on the inner peripheral surface of the outer ring 27 is formed. The shape of the tooth flank 28 a of the engaging element 28 is the same as the shape of the tooth flank 26 a of the first outer ring 26 , and the shape of the tooth flank 29 a of the engaging element 29 is the same as the shape of the tooth flank 27 a of the second outer ring 27 . The tooth flanks 28a and 29a are formed only in the circumferential central regions of the outer diameter surfaces of the engaging elements 28 and 29, and the end regions of the outer diameter surfaces of the engaging elements 28 and 29 on one side and the other side in the circumferential direction are uneven. It is formed on a smooth arc surface without (tooth surface).

It should be noted that the engaging element 29 of the present embodiment uses the engaging element 28 which is turned upside down, that is, the same parts as the engaging element 28 are used. Therefore, when the engaging element 28 is reversed with respect to the plane perpendicular to the axis X of the output shaft 22 and overlapped with the engaging element 29, the outlines of the two completely match. In this way, if the engaging elements 28 and 29 are made up of the same parts, the cost of the second clutch part 20 and thus of the clutch unit 1 can be reduced compared to the case where the engaging elements 28 and 29 are separate parts having different shapes and the like. It is advantageous in planning.

The elastic member 30 is arranged in a radially compressed state between the groove bottom of the groove 22c provided on the output shaft 22 and the engaging elements 28, 29. As shown in FIG. Therefore, the engaging elements 28 and 29 fitted into the groove 22c are always urged radially outward, and when there is no torque input to the input member 21, the tooth surfaces 28a and 29a of the engaging elements 28 and 29 are maintained. are engaged with the tooth flanks 26a, 27a of the outer rings 26, 27 facing each other, the engaging elements 28, 29 are engaged with both the output shaft 22 and the stationary member 23 in the circumferential direction. The elastic member 30 in the illustrated example is a so-called coil spring (compression coil spring) in which a wire material represented by a metal wire is spirally wound. It is of course possible to use elastic members 30 other than springs.

As described above, in the second clutch portion 20 in a state where there is no torque input to the input member 21, the engaging elements 28 and 29 engage both the output shaft 22 and the stationary member 23 in the circumferential direction, thereby 22 is locked with respect to the stationary member 23 (the rotation of the output shaft 22 with respect to the stationary member 23 is restricted). Therefore, in this locked state, reverse input torque in the forward direction with respect to the output shaft 22 (here, reverse input torque in the counterclockwise direction in FIG. 3 when the one-way clutch 20A is viewed from one side in the axial direction). In the following, "forward direction" means the same direction. 4 viewed from the side, the clockwise reverse input torque is hereinafter referred to as "reverse direction", the same direction as this.) In any case where T' is input, the reverse input torque T' The return flow to the first clutch portion 10 is cut off.

As shown in FIGS. 1 and 6, the flange portion 13c of the inner ring 13 as the input member 21 is formed with axial through holes 13c1 and 13c2. In the through-hole 13c1, the end portion of the first pin 31 on the other side in the axial direction as the "protrusion extending in the axial direction" is fixed by appropriate means such as press-fitting, adhesion, combination of press-fitting and adhesion, etc. The other end of the second pin 32 in the axial direction is fixed to the through-hole 13c2 by appropriate means similar to the first pin 31. As shown in FIG. In this embodiment, since the first pin 31 and the second pin 32 are provided three each at equal intervals in the circumferential direction, a total of six through holes for pin fixing are provided at intervals in the circumferential direction. It is

The first pin 31 rotates the output shaft 22 in the positive direction by engaging the engaging element 28 with both the output shaft 22 and the stationary member 23 (first outer ring 26) in the circumferential direction in the one-way clutch 20A. The second pin 32 functions as a "releasing force applying portion M" that applies a releasing force to the engaging element 28 for releasing the locked state that restricts 22 and the stationary member 23 (second outer ring 27) in the circumferential direction to apply a releasing force to the engaging element 29 for releasing the locked state in which the reverse rotation of the output shaft 22 is restricted. It functions as a release force application unit M'. The operation mode of the second clutch portion 20 when the locked state is released will be described in detail later.

As shown in FIG. 3, the engaging element 28 constituting the one-way clutch 20A has a first hole portion 28b into which the first pin 31 is inserted and a second hole portion 28c into which the second pin 32 is inserted. They are spaced apart in the circumferential direction. With such a configuration, the first pin 31 and the second pin 32 as the releasing force applying portion M are arranged circumferentially inward from both ends of the engaging elements 28 and 29 in the circumferential direction.

The first hole portion 28b is provided on one circumferential side of the central portion of the engaging element 28 in the circumferential direction, and the second hole portion 28c is provided on the other circumferential side of the central portion of the engaging element 28 in the circumferential direction. there is More specifically, the first hole portion 28b receives an input force when a forward torque T for releasing the locked state of the one-way clutch 20A in the locked state is input to the input member 21. It is provided on the front side in the rotational direction of the member 21 .

As shown in an enlarged view in FIG. 5, contour shapes of the first hole portion 28b and the second hole portion 28c provided in the engaging member 28 are different from each other. The second hole portion 28c is configured such that the second pin 32 engages the engaging element 28 while the forward torque T (the torque T for releasing the locked state of one of the one-way clutches 20A) is input to the input member 21. While the first hole 28b is formed in a shape that does not positively pressurize, when the torque T in the positive direction is input to the input member 21, the tooth surface 28a of the engaging element 28 and the first outer ring 26 are displaced. It has a pressurizing surface (guide surface) capable of pressurizing (guiding) the engaging element 28 in a direction (inwardly in the radial direction) in which the meshing state of the tooth surface 26a is released. Specifically, in the region of the first hole portion 28b on the front side in the rotation direction of the input member 21 that rotates as the torque T in the positive direction is input to the input member 21, the pressure surface (the guide surface) is provided. There is provided an inclined surface 28b1 that is inclined with respect to the radial direction and functions as a surface. In the one-way clutch 20A in the unloaded state where there is no input of the forward torque T to the input member 21 and no input of the reverse input torque T' in the positive direction to the output shaft 22, the first hole portion 28b The inserted first pin 31 is arranged in contact with the inclined surface 28b1, or is arranged close to the inclined surface 28b1.

The angle θ (see FIG. 5) formed by the inclined surface 28b1 provided in the first hole 28b with respect to the input direction (circumferential direction) of the torque T input to the first pin 31 is 40°±20° (20 ° to 60°). When the above angle (hereinafter referred to as "pressure angle") θ exceeds 60°, the release force required to release the meshing state (locked state) between the tooth flanks 26a and 28a, that is, This is because the force required to displace inward increases rapidly, and when the pressure angle θ falls below 20°, the amount of displacement of the engaging element 28 required to release the locked state increases rapidly. is.

As shown in FIG. 4, the engaging element 29 constituting the other one-way clutch 20B has a first hole portion 29b into which the first pin 31 is inserted and a second hole portion 29c into which the second pin 32 is inserted. are spaced apart in the circumferential direction. The second hole portion 29c is positioned forward in the rotational direction of the input member 21 when a reverse torque T for releasing the locked state of the one-way clutch 20B in the locked state is input to the input member 21. be provided. As described above, since the engaging element 28 whose front and back sides are reversed is used as the engaging element 29, the contour shape of the first hole 29b of the engaging element 29 is the same as the second hole 28c of the engaging element 28. , and a straight line extending radially through the circumferential central portions of the engaging elements 28, 29. It has the same shape as the first hole portion 28b that is inverted with respect to the straight line.

When a torque is input to the input member 21 of the second clutch portion 20 in the locked state having the above configuration in accordance with the lever operation of the first clutch portion 10, the second clutch portion 20 operates as follows. . Hereinafter, the operation mode of the second clutch portion 20 when the forward torque T is input from the first clutch portion 10 to the input member 21 will be described with reference to FIGS. 7(a) to 7(d).

When a torque T in the positive direction is input to the input member 21 and the input member 21 and the pins 31 and 32 fixed thereto begin to rotate counterclockwise together, one side of the second clutch portion 20 is rotated. In the directional clutch 20A, as shown in the left diagram of FIG. 7(a), a circumferential pressurizing force derived from the torque T acts on the inclined surface 28b1 of the first hole 28b of the engaging element 28. As shown in FIG. At this time, the second pin 32 inserted into the second hole 28b of the engaging element 28 is out of contact with the engaging element 28 in the input direction of the torque T (circumferential direction). Therefore, only the circumferential pressing force from the first pin 31 acts on the engaging element 28 . At this time, in the other one-way clutch 20B, as shown in the right diagram of FIG. 7A, the first pin 31 inserted into the first hole 29b of the engaging element 29 and the None of the second pins 32 inserted into the two holes 29c come into contact with the engaging elements 29 in the circumferential direction.

As the rotation of the input member 21 (circumferential movement of the pins 31 and 32) progresses, the engaging element 28 of the one-way clutch 20A moves toward the first pin 31 as shown in the left diagram of FIG. 7(b). While being guided along the inclined surface 28b1 in contact with the elastic member 30, it is displaced radially inward against the elastic restoring force of the elastic member 30. As shown in FIG. As a result, the engagement state between the tooth surface 28a of the engaging element 28 and the tooth surface 26a of the first outer ring 26 begins to be released. At this time, the second pin 32 inserted into the second hole 28b of the engaging element 28 is still out of contact with the engaging element 28 in the circumferential direction. At this time, in the other one-way clutch 20B, both the first pin 31 and the second pin 32 and the engaging element 29 are still out of contact with the engaging element 29, as shown in the right diagram of FIG. 7(b). is.

As shown in the left diagram of FIG. 7(c), the first pin 31 inserted into the first hole 28b of the engaging member 28 is positioned at the outermost diameter portion of the first hole 28b (the front side in the rotational direction of the input member 21). ), the tooth surface 28a of the engaging element 28 and the tooth surface 26a of the first outer ring 26 are completely disengaged. At this time, the second pin 32 inserted into the second hole portion 28c of the engaging member 28 also radially contacts the outermost diameter portion of the second hole portion 28c on the front side of the input member 21 in the rotational direction. This restricts further radially inward displacement of the engaging element 28 . When the tooth surface 28a of the engaging element 28 and the tooth surface 26a of the first outer ring 26 are completely disengaged from each other as described above, the output shaft 22 moves in the torque T input direction to the engaging element 28 and the like. together with the input member 21 [see also the left diagram of FIG. 7(d)].

As described above, when the engagement state between the tooth surface 28a of the engaging element 28 and the tooth surface 26a of the first outer ring 26 is completely released in the one-way clutch portion 20A, in the other one-way clutch portion 20B, As shown in the right diagram of FIG. 7(c), the first pin 31 inserted into the first hole 29b of the engaging element 29 and the second pin 32 inserted into the second hole 29c of the engaging element 29 are input. The front side of the member 21 in the rotational direction comes into contact with the engaging element 29 in the circumferential direction. As a result, the torque T input to the input member 21 can be transmitted to the output shaft 22 via the pins 31 and 32 and the engaging element 29 in the one-way clutch portion 20B. When the torque T is continuously input to the input member 21 in this state, in the one-way clutch portion 20B, the tooth flank 27a of the second outer ring 27 and the tooth flank 29a of the engaging element 29 meshing therewith are inclined. Because the direction of inclination of the surface is substantially parallel to the input direction of the torque T, and the fact that the engaging element 29 is always urged radially outward by the elastic member 30, the engaging element 29 is pushed toward the second outer ring 27. The output shaft 22 rotates integrally with the input member 21 while repeating the displacement radially inward and outward along the shape of the tooth surface 27a of (see the right diagram of FIG. 7(d)).

Although detailed description is omitted, when the torque T in the reverse direction is input from the first clutch portion 10 to the input member 21, the one-way clutch portion 20B receives the torque T in the forward direction from the first clutch portion. The one-way clutch portion 20A operates in the same manner as the one-way clutch portion 20A when the input is input to the member 21, and the one-way clutch portion 20A is the one-way clutch when the torque T in the positive direction is input to the input member 21 from the first clutch portion. It operates similarly to section 20B. As a result, the output shaft 22 rotates integrally with the input member 21 and the like in the opposite direction.

As described above, in the one-way clutch 20A comprising the reverse input cut-off clutch according to the embodiment of the present invention, the torque T is input to the input member 21, and the first outer ring constituting the stationary member 23 26 (the locked state of the output shaft 22). Circumferentially inner than both ends, that is, within the circumferential range of the engaging element 28 . In this case, the input member 21 has a column portion (between two circumferentially adjacent engagers 28 and an output shaft portion) provided in the conventional input member described with reference to FIGS. 22, and pressurizes the engaging element 28 as the input member 21 rotates.

Therefore, the groove defining portion 22d provided on the output shaft 22 can be expanded radially outward compared to the conventional structure, and the contact length between the engaging element 28 and the groove defining portion 22d can be increased. In this embodiment, as shown in FIG. The recessed groove defining portion 22d can be brought into contact with substantially the entire peripheral end surface of the joint 28. As shown in FIG. As a result, as the reverse input torque T′ (in the forward direction) is input to the output shaft 22, the engaging element 28 fitted in the groove 22c of the output shaft 22 is displaceable in the radial direction. It is possible to suppress or prevent the engaging element 28 from tilting with respect to the depth direction of the recessed groove 22c when the forming portion 22d contacts. Therefore, when the one-way clutch 20A, which is the reverse input cutoff clutch, is in the locked state, when a torque T in the forward direction is input to the input member 21 (because the locked state is released in accordance with the input of this torque T). is applied to the engaging element 28 from the first pin 31 as the releasing force applying portion M), the engaging element 28 can be smoothly displaced radially inward along the groove 22c. can.

Further, in the one-way clutch 20A, the first pin 31 as the releasing force applying portion M is located forward of the rotation center C of the engaging element 28 in the concave groove 22c of the engaging element 28 in the input direction of the torque T in the positive direction. It is arranged so as to apply the above-mentioned pressure force to the engaging element 28 in the side area (see FIG. 5).

In this way, when the positive reverse input torque T' is input to the output shaft 22, the engaging element 28 fitted in the groove 22c is inclined with respect to the depth direction of the groove 22c. Even when the engaging element 28 is rotating in the concave groove 22c, the first pin 31 disengages the engaging element 28 from the first pin 31 as the positive torque T is input to the input member 21. When a force is applied, a force in a direction that cancels the inclination (rotation) is applied to the engaging element 28, and the engaging element 28 can be returned to the proper posture. As a result, when the torque T in the positive direction is input to the input member 21, the engaging element 28 can be displaced radially inward smoothly.

The effects that can be enjoyed with one of the one-way clutches 20A described above can also be enjoyed with the other one-way clutch 20B having the same structure. For this reason, the second clutch portion 20 having the one-way clutches 20A and 20B, which are lock type reverse input cut-off clutches, has excellent operability. The clutch unit 1 is characterized by excellent operability and operability.

The clutch unit 1 including the second clutch portion 20 provided with the one-way clutches 20A and 20B, which are reverse input cutoff clutches, according to one embodiment of the present invention has been described above. The input cutoff clutch is not limited to this.

For example, in the above embodiment, the releasing force applying portion M is configured by the pins 31 and 32 fixed to the input member 21 (inner ring 13), but the releasing force applying portion M may be provided integrally with the input member 21. can also FIG. 8 is a schematic perspective view of an input member 21 integrally having a releasing force applying portion M. In this input member 21, release is performed by claw portions 13e and 13f provided between two circumferentially adjacent claw portions 13d. A force applying section M is configured. When the input member 21 shown in FIG. 8 is incorporated into the clutch unit 1 shown in FIG. 1, the claw portion 13e is inserted into the first holes 28b and 29b of the engaging elements 28 and 29, and the claw portion 13f is inserted into the engaging elements 28 and 29. 29 are inserted into the second holes 28c and 29c.

In the one-way clutch 20A that is a reverse input cutoff clutch, two engaging elements 28 may be provided at intervals in the circumferential direction as shown in FIG. You may provide (illustration omitted). Although illustration is omitted, the same applies to the one-way clutch 20B (engager 29) composed of a similar reverse input cutoff clutch.

Further, in the second clutch portion 20 of the clutch unit 1 shown in FIG. 10, the second pin 32 (either one of the two axial projections) is omitted. I don't mind. In this case, the first pin 31 and the hole into which the first pin 31 is inserted are preferably arranged on a straight line extending radially through the circumferential central portion of the engaging element. This allows the first pin 31 to function as the releasing force applying portion M for the two one-way clutches 20A and 20B.

By the way, for example, in the one-way clutch 20A shown in FIGS. Although it has been described that radially inward displacement of the engaging element 28 is restricted by contacting the outermost diameter portion of the second hole 28c of the engaging element 28 in the radial direction, the one-way clutch 20A does not have an engaging member. A displacement limiter may also be provided to limit excessive radially inward displacement of the clasp 28 beyond the compression limit of the elastic member 30 . Specific examples of the displacement limiting portion that can be provided in the one-way clutch 20A will be described below with reference to FIGS. A configuration (displacement limiter) is applied.

The one-way clutch 20A shown in FIG. 11 is integrally formed at the base of the recessed groove defining portion 22d of the output shaft 22 so as to be arranged at the ends of the groove bottom of the recessed groove 22c on one side and the other side in the circumferential direction. The convex portion 22e is used as the displacement limiting portion 40, and a compression coil spring as the elastic member 30 is arranged in a compressed state between the pair of convex portions 22e. The convex portion 22e is sized and arranged such that its radially outer end is located radially outward by a predetermined amount from the radially outer end of the elastic member 30 (compression coil spring) that has reached its compression limit. The shape (radial outer end position) is adjusted.

Therefore, for example, even if an impact load in the same direction as the torque T is input to the input member 21 and the engaging element 28 is vigorously displaced inward in the radial direction, the engaging element 28 will not reach the compression limit of the elastic member 30. Since it engages with the convex portion 22e in the radial direction before reaching, it is possible to restrict (prevent) the engaging element 28 from being displaced radially inward so as to exceed the compression limit of the elastic member 30. FIG. As a result, the elastic restoring force originally possessed by the elastic member 30 is lost ("settling" occurs in the compression coil spring), and as a result, the engaging element 28 is smoothly displaced radially outward (reverse input interrupting clutch can be smoothly shifted from the unlocked state to the locked state). Therefore, the durability and reliability of the one-way clutch 20A, which is a reverse input cutoff clutch, can be enhanced.

A one-way clutch 20A shown in FIG. 12 has a protrusion 22f formed integrally with the output shaft 22 so as to be arranged in the circumferential center of the groove bottom of the recessed groove 22c as the displacement limiter 40. The radially outer end of the portion 22f is located at the radially outer end when the elastic member 30 (compression coil spring) disposed circumferentially outside the convex portion 22f within the groove 22c reaches its compression limit. The size and shape (position of the radially outer end portion) are adjusted so that the radially outer end portion is positioned radially outward by a predetermined amount. As a result, the same effects as those of the one-way clutch 20A shown in FIG. 11 can be obtained.

The one-way clutch 20A shown in FIGS. 13 and 14 is a specific example in which the displacement limiting portion 40 is provided integrally with the engaging element 28 instead of the output shaft 22. In FIG. The radially inwardly protruding protrusions 28d provided on the outer edges are defined as displacement limiting portions 40, and in FIG. 28d is a displacement limiting portion 40. As shown in FIG. Before the elastic member 30 (compression coil spring) interposed in a compressed state between the engaging member 28 and the groove bottom of the groove 22c reaches the compression limit, the convex portion 28d is formed such that the radially inner end thereof forms the groove. The size and shape are adjusted so as to contact the groove bottom of 22c. As a result, the same effects as those of the one-way clutch 20A shown in FIG. 11 can be obtained.

A one-way clutch 20A shown in FIG. 15 is an example of a case where the displacement limiting portion 40 is configured by a separate member 33 different from the output shaft 22 and the engaging element 28, and is formed in the circumferential central portion of the groove bottom of the concave groove 22c. A separate member 33 functioning as a displacement limiting portion 40 is fixed to the fixed portion 22h. That is, this embodiment corresponds to a configuration in which the convex portion 22f shown in FIG. 12 is replaced with a separate member 33. Although not shown, the separate member 33 functioning as the displacement restricting portion 40 may be provided on the engaging element 28 instead of the output shaft 22 (fixed to the engaging element 28).

In the reverse input cut-off clutch according to the embodiment of the present invention described above, the pins 31 and 32 (FIG. 6) or the claw portions 13e and 13f (FIG. 8) serving as projections extending in the axial direction and forming the release force applying portion M ) is provided in the input member 21, and the holes 28b, 28c, 29b, and 29c into which the releasing force applying portion M is inserted are provided in the engaging members 28 and 29. The member provided with the hole into which the portion M is inserted may be reversed. That is, for example, the pins 31 and 32 constituting the releasing force applying portion M may be provided in the engaging members 28 and 29, and a hole portion into which the releasing force applying portion M is inserted may be provided in the input member 21 (not shown). .

The clutch unit 1 including the reverse input cut-off clutch according to the embodiment of the present invention described above can be used not only for seat lifters for adjusting the seat surface height of automobile seats, but also for electric sliding doors, power windows, and electric steering. It is possible to incorporate it into a driving mechanism such as

The second clutch unit 20 including the one-way clutches 20A and 20B, which are reverse input cutoff clutches, according to the embodiment of the present invention, and the clutch unit 1 including the same have been described above, but the present invention has been described above. It is needless to say that the present invention is not limited to the embodiment, and can be embodied in various forms without departing from the gist of the present invention. The scope of the present invention is indicated by the scope of the claims, and includes equivalent meanings and all changes within the scope of the claims.

1 clutch unit 10 first clutch portion 13 inner ring (input member)
20 Second clutch portion (reverse input cutoff clutch)
21 Input member 22 Output shaft 22c Groove 22d Groove defining portion 22e Protruding portion (displacement limiting portion)
22f convex portion (displacement limiting portion)
23 Stationary member 26 First outer ring 26a Tooth surface 27 Second outer ring 27a Tooth surface 28 Engager 28a Tooth surface 28d Convex portion (displacement limiting portion)
29 Engaging piece 29a Tooth surface 30 Elastic member 31 First pin 32 Second pin 40 Displacement limiting portion M Release force applying portion T Torque T' Reverse input torque

Claims (7)

An input member to which torque is input, an output shaft capable of outputting the torque, a stationary member whose rotation is restricted, and a plurality of circumferentially spaced intervals between the output shaft and the stationary member. and an engaging element,
each engaging element is fitted in a concave groove formed in the output shaft so as to be displaceable in the radial direction;
An elastic member is interposed between the groove bottom of the recessed groove and the engaging element in a state of being radially compressed,
The engaging element that receives the elastic restoring force of the elastic member engages the stationary member and the output shaft in the circumferential direction, thereby locking the rotation of the output shaft with respect to the stationary member and allowing torque input to the input member. A reverse input interrupting clutch in which the engagement element and the stationary member are disengaged by displacing the engagement element radially inward against the elastic restoring force associated with
A releasing force imparting portion that imparts a releasing force to the engaging element for releasing the state of engagement with the stationary member in response to torque input to the input member is positioned more circumferentially than both ends of the engaging element in the circumferential direction. A reverse input cut-off clutch, characterized in that it is arranged inside. 2. The method according to claim 1, wherein the releasing force applying section applies the releasing force to the engaging element in a region of the engaging element on the front side in the torque input direction from the center of rotation of the engaging element in the concave groove. A reverse input blocking clutch as described. 2. The reverse input according to claim 1, wherein the input member is provided with a convex portion extending in the axial direction forming the releasing force applying portion, and the engaging element is provided with a hole into which the convex portion is inserted. shut-off clutch. 2. A reverse input cut-off clutch according to claim 1, further comprising a displacement limiting portion that limits radially inward displacement of said engaging element before said elastic member reaches a compression limit. 5. A reverse input interrupting clutch according to claim 4, wherein said displacement limiting portion is provided on said output shaft. 5. A reverse input interrupting clutch according to claim 4, wherein said displacement limiting portion is provided on said engaging element. A first clutch part for controlling transmission and interruption of torque input by lever operation, and a second clutch part comprising the reverse input interruption clutch according to any one of claims 1 to 6, wherein the first A clutch unit in which an output of a clutch portion is input to the input member.

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