JP5894788B2 - Clutch unit - Google Patents

Description

  The present invention relates to a clutch unit used in a vehicle seat height adjustment mechanism or the like.

  In the height adjustment mechanism for a vehicle seat, the output shaft rotates by operating a lever provided on the input side that swings up and down. However, the weight of the seat and the occupant applies a force to the seat to lower the seat. However, a clutch unit configured so that the output shaft does not rotate is used.

  Such a clutch unit transmits a driving force to the output shaft when the lever is moved up and down from the neutral position, but does not transmit a driving force when the lever is returned from the upper or lower position to the neutral position. There is provided a mechanism and a brake mechanism that transmits input torque from the ratchet mechanism to the output shaft but does not transmit reverse input torque from the output shaft to the ratchet mechanism. The clutch unit is provided with a return spring for returning the lever to the neutral position (Patent Documents 1 and 2).

JP 2011-153675 A JP 2011-163542 A

  However, in the conventional clutch unit, the clutch mechanism and the ratchet mechanism itself (the engaging portion of the component group that realizes torque transmission / cutoff) is housed in the housing, but the return spring is exposed to the outside of the housing. It was. For this reason, dust may adhere to the return spring or a string-like object may be tangled, resulting in malfunction.

  In addition, the clutch unit is required to be reduced in size and weight while ensuring a sufficient braking force against the force input to the output shaft.

  Therefore, an object of the present invention is to suppress dust from adhering to a return spring provided in a clutch unit. Another object of the present invention is to ensure the braking force of the clutch unit and to reduce the size and weight.

The present invention for achieving the above-described object includes a ratchet mechanism that is provided on the input side and transmits / cuts off an input torque generated by a swinging operation of an operation member to which a lever is attached, and is provided on the output side. thereby transmitting an input torque to the output shaft of a clutch unit and a brake mechanism for blocking reverse input torque from said output shaft, said brake mechanism includes a brake-side outer race with respect to the brake-side outer race as well as a rotatable and a brake-side cam does not rotate relative to the brake-side outer race when blocking a reverse input torque from the output shaft, the ratchet mechanism can transmit the rotational force to the brake cam such a first rotating member, the operation and the second rotary member swingable integrally with member, the first rotating body and the engagement or disengagement child to the second rotary member A housing in a movable piece which transmits and interruption of the input torque from the operating member, a return spring for returning the operating member to the neutral position, which covers at least from the radially outer side of the movable piece and the return spring, The operating member is made of one component and is located in the housing, the lever is mounted outside the housing and the lever is attached to the lever. The rotating body and the lever mounting portion are connected to each other, and a connecting portion that penetrates into and out of the housing is provided .

According to such a configuration, not only the variable Dohen, also the return spring, so to be covered with the housing at least from the radially outer side, is inhibited from dust return spring is attached. Moreover, it can also suppress that a string-like object is entangled with a return spring. Furthermore, since the cover return spring with a housing for covering the soluble Dohen, the housing covering the variable Dohen in comparison with the case of separately configure another housing, reducing the number of parts, the size and weight Can be planned.

  In the clutch unit described above, it is desirable that the housing also serves as the brake-side outer ring.

  According to this, the number of parts can be reduced and weight reduction can be achieved.

In this clutch unit, the housing has a front Symbol brake side outer ring, fitted to the outer periphery of the brake-side outer race, it is desirable that the a cover member for covering the input side of the side surface of the movable piece.

  In this way, when the cover member is fitted to the outer periphery of the brake side outer ring, the cover member reinforces the outer periphery of the brake side outer ring and suppresses deformation of the brake side outer ring in the radial direction, thereby improving the braking force. Can be planned.

In this clutch unit, the cover member, the pre-listen Dohen, it is desirable that restricts the movement to the input side.

In this way, by regulating the cover member from moving variable dynamic piece to the input side, as compared with the case of using other components, to suppress the axial thickness, it can be miniaturized.

  In this clutch unit, it is preferable that the lever mounting portion extends radially outward from the outer periphery of the housing.

  According to this, since the distance from the swing center becomes long at the tip of the lever mounting portion, it is easy to transmit the rotational torque from the lever to the lever mounting portion when the lever is mounted on the lever mounting portion. Therefore, since the load applied to the lever is small, the durability of the lever can be improved even when the lever is made of resin.

  In the configuration in which the operation member has a connection portion, the return spring can be held by the connection portion.

  According to this, many functions can be given to an operation member, and a number of parts can be reduced.

  In this clutch unit, the operation member has a spring support part that enters the housing on the opposite side of the connection part across the swing axis, and both ends of the return spring are connected to the spring support part. It can be locked.

  According to this, the adhesion of dust at the end of the return spring can be suppressed with a simple configuration.

According to the configuration of the first aspect, it is possible to suppress dust from adhering to the return spring, reduce the number of parts, and achieve compactness.

According to the configuration of the second aspect, the weight can be reduced by reducing the number of parts , and the braking force can be improved by suppressing the radial deformation of the brake side outer ring.

According to the structure of Claim 3 , the axial thickness of a brake unit can be suppressed and size reduction can be achieved.

According to the structure of Claim 4 , the burden of a lever can be made small.

According to the structure of Claim 5 , the number of parts can be reduced.

According to the structure of Claim 6 , the adhesion of the dust at the end part of the return spring can be suppressed with a simple structure.

It is a side view of the vehicle seat to which the clutch unit is applied. It is the front view which is (a) input side of a clutch unit, (b) side view, and (c) the rear view which is an output side. It is a disassembled perspective view of a clutch unit. It is IV-IV sectional drawing of FIG. It is the (a) front view and (b) side view of a posture control member. It is (a) front view of the state which combined the lever member and the return spring, and (b) side view. It is a front view of the state which combined the main axis | shaft, ratchet side outer ring | wheel, a roller holder | retainer, an attitude | position control member, a roller, a spring, a return spring, and a lever member. It is a front view of the state which combined the main axis | shaft, the brake side outer ring | wheel, the brake side cam, the transmission member, the roller, and the spring. It is figure (a)-(c) explaining operation | movement of a ratchet mechanism. It is figure (a)-(c) explaining operation | movement of a brake mechanism.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. As shown in FIG. 1, the clutch unit 1 of the present invention is applied to a known height adjustment mechanism (not shown) for adjusting the height of a seat cushion S1 of a vehicle seat S. In the clutch unit 1, a lever LV is attached to a lever member 13 as an example of an operation member, and by operating the lever LV, an output gear 21D (see FIG. 2) described later as an output shaft is rotated to drive a height adjustment mechanism. Thus, the height of the seat cushion S1 can be adjusted. Specifically, when the lever LV is raised from the neutral position N, the seat cushion S1 is raised by a predetermined amount, and when the lever LV is lowered from the neutral position N, the seat cushion S1 is lowered by a predetermined amount. When the lever LV is returned from the upper or lower position to the neutral position N, the output gear 21D does not rotate.

  As shown in FIGS. 2A to 2C, in the clutch unit 1, each member is housed in the housing 10, and only the main shaft 21 having the output gear 21D and the lever member 13 protrude from the housing 10. It has become. For this reason, it is difficult for dust to adhere to each component in the clutch unit 1, and it is suppressed that the string-like thing etc. which the passenger | crew carry are entangled with each component. In the following description, as shown in FIG. 2B, the side on which the lever member 13 is disposed is referred to as “input side”, and the side on which the output gear 21D is disposed is referred to as “output side”.

  As shown in FIG. 3, the clutch unit 1 is provided on the input side, and is provided with a ratchet mechanism 2 that transmits and interrupts input torque generated by the swinging motion of the lever member 13, and an input from the ratchet mechanism 2. A brake mechanism 3 is provided that transmits torque to the output gear 21D and blocks reverse input torque from the output gear 21D.

The outline of the components of the ratchet mechanism 2 and the brake mechanism 3 will be described. The ratchet mechanism 2 includes a cover member 12, a lever member 13, a posture regulating member 14, a roller retainer 15, a ratchet side outer ring 16, and a movable member. A roller 91 as an example of a piece and a return spring 95 as an urging member are provided. The brake mechanism 3 includes a brake side outer ring 11, a brake side cam 18, a transmission member 17, and a roller 92. The main shaft 21 outputs the rotation of the brake cam 18 to the outside and supports the rotation of the ratchet mechanism 2. The housing 10 described above is configured by a combination of a brake side outer ring 11 and a cover member 12. That is, the housing 10 also serves as the brake side outer ring 11. The main shaft 21 for extracting power from the brake mechanism 3 has a support shaft portion 21A having a plurality of types of diameters, a rotary engagement shaft portion 21B having a square cross section, a flange 21C, and an output gear from the input side to the output side. 21D in this order.

Next, details of the configurations of the brake mechanism 3 and the ratchet mechanism 2 will be described.
The brake-side outer ring 11 includes a cylindrical outer peripheral portion 11A and an output-side side wall 11B connected to the outer peripheral portion 11A. The inner peripheral surface 11C of the brake side outer ring 11 is a cylindrical surface. The side wall 11B is formed with a hole 11D having substantially the same diameter as the flange 21C of the main shaft 21. As shown in FIG. 4, the flange 21 </ b> C enters the hole 11 </ b> D and reduces the gap with the brake-side outer ring 11 to suppress dust from entering the housing 10.

  Returning to FIG. 3, the brake-side cam 18 is a slightly thin member having a thickness equivalent to the axial length of the roller 92, and is rotatable relative to the brake-side outer ring 11 when the lever LV is operated. The brake cam 18 has a plate-like main body 18A and a first protrusion 18D. The outer peripheral surface of the main body 18A has circular outer peripheral surfaces 18B having a circular cross section and cam surfaces 18C made of a plane alternately in the circumferential direction. Each cam surface 18C is arranged at four equal pitches in the circumferential direction. The cam surface 18C is a surface that is not parallel to the inner peripheral surface 11C of the brake-side outer ring 11, and the wedge-shaped space 81 (see FIG. 8) formed between the inner peripheral surface 11C and the cam surface 18C is the center in the circumferential direction. As it goes from the outside to the outside, the size in the radial direction becomes smaller. That is, the wedge-shaped space 81 has a wedge shape in which the tip is tapered toward both sides in the circumferential direction.

  The first protrusion 18D is a small protrusion formed toward the transmission member 17 side (input side), and is provided at a position corresponding to the circular outer peripheral surface 18B in the circumferential direction on the edge of the outer peripheral portion. The amount of protrusion of the first protrusion 18D is preferably equal to or greater than the thickness of the transmission member 17, and is more preferably substantially the same. As a result, the force applied from the transmission member 17 to the engaging portion of the brake cam 18 is reduced, the load is reduced, and the first projecting portion 18D does not project excessively, so that the weight can be reduced. The first protrusion 18D can be formed at a low cost by being formed by half blanking. Further, because of this processing method, a recess corresponding to the first protrusion 18D is formed on the back side (output side) of the first protrusion 18D. A rotation engagement hole 18E having a square cross section is formed at the center of the main body 18A. The rotation engagement hole 18E has a shape corresponding to the rotation engagement shaft portion 21B, and is fitted to the rotation engagement shaft portion 21B as shown in FIG. As a result, the brake cam 18 and the main shaft 21 rotate together.

  Returning to FIG. 3, the roller 92 is an example of a first movable piece, and is a member that locks and unlocks the rotation of the brake cam 18 by engaging and disengaging the brake cam 18 and the brake outer wheel 11. is there. As shown in FIG. 8, a pair of rollers 92 are included in each wedge-shaped space 81 formed between the brake side outer ring 11 and the brake side cam 18, and a spring 96 is interposed between the pair of rollers 92. Has been placed. The spring 96 always urges the rollers 92 away from each other, so that the rollers 92 are pushed into the narrower ends of the wedge-shaped space 81 and are not operating (the lever LV is in the neutral position N). ) Between the inner peripheral surface 11C of the brake side outer ring 11 and the cam surface 18C of the brake side cam 18. For this reason, even if reverse input torque is applied to the output gear 21D and the brake side cam 18 tries to rotate with respect to the brake side outer ring 11, one of the pair of rollers 92 is moved to the narrower side of the wedge-shaped space 81. Since it is pushed in, it cannot rotate. That is, the reverse input torque from the output gear 21D is cut off.

  As shown in FIG. 4, the roller 92 is slightly longer than the thickness of the main body 18A of the brake cam 18 and is provided so as to partially protrude from the main body 18A to the input side. Specifically, the roller 92 protrudes from the main body 18A so that the pure cylindrical surface excluding the rounded shape of the end includes the entire width of the transmission member 17 in the axial direction. The output side end face of the roller 92 and the outside in the radial direction (radial direction centered on the main shaft 21) are covered with the brake side outer ring 11.

  Returning to FIG. 3, the transmission member 17 can come into contact with the roller 92 to disengage the roller 92 from the brake side cam 18 and the brake side outer ring 11 (cancel the clamping by the brake side cam 18 and the brake side outer ring 11). And a member capable of transmitting the input torque from the ratchet mechanism 2 to the brake cam 18 by engaging with the brake cam 18. The transmission member 17 has a thin flat plate shape, is adjacent to the input side with respect to the main body portion 18A of the brake side cam 18, and is provided in contact with the main body portion 18A. The transmission member 17 has eight substantially rectangular cutouts 17A that are open toward the radially outer side on the outer periphery. And the remaining part in which notch 17A is not formed among the outer peripheral parts of transmission member 17 is large diameter part 17B which has a circular outer peripheral surface. A step 17C adjacent to the large diameter portion 17B of the notch 17A engages with the roller 92 to unlock the brake cam 18 or engages with the first protrusion 18D to the brake cam 18. It is a part that transmits input torque.

  The cutouts 17A have the same circumferential size, and are provided at equal pitches in the circumferential direction. As shown in FIGS. 8 and 4, four notches 17 </ b> A provided every 90 degrees receive the rollers 92, and the remaining four receive the first protrusions 18 </ b> D of the brake cam 18. In FIG. 4, the engagement between the first protrusion 18D and the notch 17A is a displacement view of the section deviated from the line IV-IV in FIG.

  In the present embodiment, the first opening that can receive and engage the first protrusion 18D and the second opening that can receive and engage the first movable piece (roller 92) in the present embodiment Is also realized by the notch 17A. As described above, the first opening and the second opening are provided on the outer periphery of the transmission member 17, that is, the portion farthest from the center of the main shaft 21, so that the first opening and the first protrusion are in contact with each other. The radius of rotation at the contact point can be increased. Therefore, the force applied to the edge of the first opening (stepped portion 17C) can be reduced, and the thickness of the transmission member 17 can be reduced.

  The first openings (notches 17A containing the first protrusions 18D) and the second openings (notches 17A containing the rollers 92) are alternately arranged in the circumferential direction in this embodiment. For this reason, a force is applied to the transmission member 17 in a balanced manner during operation, and the transmission member 17 can be smoothly rotated. Further, since both the first opening and the second opening are realized by notches 17A that are equivalent to each other, when the transmission member 17 is combined with the brake side cam 18, the first opening 18D is engaged with the first protrusion 18D. There is no need to select the notch 17A, and erroneous assembly can be prevented.

  During non-operation, the roller 92 is in contact with the inner peripheral surface 11C of the brake side outer ring 11 and the cam surface 18C of the brake side cam 18, but is slightly separated from the stepped portion 17C of the transmission member 17. A distance G1 between the stepped portion 17C and the roller 92 is smaller than a circumferential distance G2 between the stepped portion 17C of the notch 17A receiving the first protruding portion 18D and the first protruding portion 18D.

  Returning to FIG. 3, the transmission member 17 has a through hole 17 </ b> D through which the main shaft 21 passes at the center. Further, the transmission member 17 is formed with an engaging hole 17E penetrating radially inward of the notch 17A. The engagement holes 17E are arranged at an equal pitch in the circumferential direction.

  The ratchet-side outer ring 16 is an example of a first rotating body that is provided adjacent to the transmission member 17 on the input side in the axial direction and is rotatable integrally with the transmission member 17 and is formed in a cup shape by sheet metal. . The ratchet side outer ring 16 includes a cylindrical outer peripheral portion 16A and an output side wall 16B connected to the outer peripheral portion 16A. The inner peripheral surface 16C of the ratchet side outer ring 16 is a cylindrical surface. The side wall 16B has a second protrusion 16D that protrudes toward the output side by half blanking. The second protrusion 16D is provided with a size and an arrangement corresponding to the engagement hole 17E, and is engaged with the engagement hole 17E as shown in FIG. As a result, the ratchet side outer ring 16 and the transmission member 17 rotate integrally. A circular hole 16 </ b> E is formed at the center of the ratchet side outer ring 16, and the ratchet side outer ring 16 is connected to the main shaft 21 and the housing 10 by fitting the hole 16 </ b> E into the support shaft portion 21 </ b> A of the main shaft 21. It can be rotated.

  The roller holder 15 is a member for holding the roller 91 at a predetermined position along the inner periphery of the ratchet side outer ring 16. The roller retainer 15 has a circular hole 15A, and the position of the hole 15A with respect to the main shaft 21 is determined by fitting the hole 15A into the support shaft portion 21A of the main shaft 21. In the upper half of the outer periphery of the roller retainer 15, an arc-shaped roller retaining portion 15B is formed on the upper half of FIG. Yes. Two roller holding portions 15B are formed, and a roller holding wall 15C extending radially outward is provided at the upper end of the roller holding portion 15B, and radially outward at the lower end. An extended spring support wall 15D is provided. Further, the roller retainer 15 is formed with two posture regulating walls 15E extending from the center toward the left and right obliquely downward directions in FIG.

  As shown in FIG. 7, a roller 91 is arranged in a region adjacent to the roller holding wall 15 </ b> C in the space between the roller holding portion 15 </ b> B and the inner peripheral surface 16 </ b> C of the ratchet side outer ring 16. The roller 91 is a member that transmits and blocks input torque from the lever member 13 by being engaged and disengaged from the ratchet side outer ring 16 and a ratchet side cam 13C described later. A spring 97 is disposed between the roller 91 and the spring support wall 15D, and the roller 91 is constantly urged toward the roller holding wall 15C by the spring 97.

  The posture restricting member 14 is a member for restricting the posture of the roller retainer 15 with respect to the housing 10 as shown in FIGS. 3 and 5. The posture regulating member 14 includes a main body arm 14A extending in the radial direction, a hole 14B, a spring holding portion 14C, and a spring support portion 14D. The hole 14B is formed at the center of the main body arm 14A. The spring holding portion 14C is formed to extend from the main body arm 14A toward the output side (the roller holder 15 side) in a 45 degree direction with respect to the lower direction in FIG. Further, the spring holding portion 14C is engaged with the attitude regulating wall 15E of the roller holder 15, whereby the roller holder 15 and the attitude regulating member 14 are directions around the axis of the main shaft 21 (rotating direction). With respect to each other. The spring support portion 14D is formed to extend from the lower portion of the main body arm 14A toward the output side.

  The cover member 12 includes a cylindrical outer peripheral portion 12A and an input side wall 12B connected to the outer peripheral portion 12A. The side wall 12B is formed with an operation opening 12C that extends from the center toward the top of FIG. Further, in the lower half region of the side wall 12B, a spring locking opening 12D extending in a left and right arc shape is formed. Of the side wall 12B, the periphery of the upper edge of the operation opening 12C is a recess 12E that is recessed toward the output side. The portion of the side wall 12B constituting the recess 12E covers the side surface on the input side of the roller 91 and restricts the roller 91 from moving to the input side (see FIG. 4). In this way, by restricting the movement of the roller 91 to the input side by the cover member 12, the axial thickness is suppressed and the size of the clutch unit 1 can be reduced as compared with the case of using other components. Has been. In the outer peripheral portion 12A, notches 12F that are open toward the output side are formed at two locations on the left and right sides (only one is shown in FIG. 3).

  The cover member 12 has an outer peripheral portion 12A fitted on the outer side of the outer peripheral portion 11A of the brake side outer ring 11, and is integrated with the brake side outer ring 11 by welding or the like. And the front-end | tip part of 14 A of main body arms engages with each notch 12F of the cover member 12, and, thereby, the attitude | position of the attitude | position control member 14 and the roller holder 15 with respect to the housing 10 is being fixed. . That is, the roller retainer 15 is a stationary member that does not rotate relative to the housing 10 even when the lever LV is operated.

  As shown in FIGS. 3 and 6, the lever member 13 includes a lever mounting portion 13A, a ratchet side cam 13C, a connection portion 13E, and a spring support portion 13G.

The lever attachment portion 13 </ b> A is disposed outside the housing 10. The lever attachment portion 13A extends from the center to the left and right in FIG. 3, and is a portion to which the lever LV is attached. A circular hole 13B is formed at the center of the lever mounting portion 13A, and the lever mounting portion 13A can swing with respect to the housing 10 by fitting the hole 13B into the support shaft portion 21A.
The lever attachment portion 13 </ b> A extends outward in the radial direction from the outer periphery of the housing 10, that is, the outer periphery 12 </ b> A of the cover member 12. Therefore, the tip of the lever mounting portion 13A has a long distance from the swing center, and when the lever LV is mounted on the lever mounting portion 13A, it is easy to transmit the rotational torque from the lever LV to the lever mounting portion 13A. Thereby, since the reaction force applied to the lever LV from the lever mounting portion 13A when the lever LV is operated is small, the durability of the lever LV can be improved even when the lever LV is made of resin.

  The ratchet cam 13C is disposed inside the housing 10 and has two flat cam surfaces 13D as outer peripheral surfaces that are not parallel to the inner peripheral surface 16C of the ratchet outer ring 16 in the upper part of FIG. The cam surface 13D is disposed approximately corresponding to the position of the roller holding wall 15C. The ratchet side cam 13 </ b> C is an example of a second rotating body, and is configured as a part of the lever member 13, so that it can swing integrally with the lever member 13.

  The connecting portion 13E is a member that penetrates the inside and outside of the housing 10 through the operation opening 12C of the cover member 12 and connects the ratchet cam 13C and the lever mounting portion 13A.

  The spring support portion 13G is disposed on the opposite side of the connection portion 13E across the swing axis of the lever member 13 (same as the central axis of the main shaft 21), and extends to the output side to open the spring locking opening of the cover member 12 It enters into the housing 10 through 12D. A spring locking groove 13F is formed in the left and right outer edges of the portion of the spring support portion 13G that has entered the housing 10.

  The lever member 13 is assembled to the support shaft portion 21A, and is not detached from the support shaft portion 21A by fixing the lock member 22 to the support shaft portion 21A. Although the lock member 22 is simplified in the drawing, for example, a nut or the like that is screwed into the support shaft portion 22A can be employed.

The return spring 95 is a member obtained by bending a spring wire, and includes a circular portion 95A that extends in a circular shape with a lower end cut off, and an engagement end portion 95B that extends radially outward from both ends of the circular portion 95A. The return spring 95 is accommodated in the housing 10, and the outer side in the radial direction is completely covered by the housing 10.
As shown in FIG. 7, the circular portion 95 </ b> A is held on the outer peripheral surface of the connecting portion 13 </ b> E of the lever member 13 and the outer peripheral surface of the spring holding portion 14 </ b> C of the posture regulating member 14. The engaging end portion 95 </ b> B is engaged with the spring support portion 14 </ b> D of the posture regulating member 14 and the spring locking groove 13 </ b> F of the lever member 13. While the spring support portion 14D remains stationary even when the lever member 13 swings, the spring locking groove 13F moves due to the swing of the lever member 13, so that the lever member 13 is swung from the neutral position N. In some cases, the force applied from the return spring 95 to the spring locking groove 13F acts as a force for returning the lever member 13 to the neutral position N as shown in FIG.

The operation of the clutch unit 1 configured as described above will be described.
9A, the roller 91 is positioned between the inner peripheral surface 16C of the ratchet side outer ring 16 and the cam surface 13D of the lever member 13 as shown in the partially enlarged view. There is a slight gap between them, and they are not sandwiched between them. The roller 91 is pressed against the roller holding wall 15 </ b> C by a spring 97.
As shown in FIG. 9B, when the lever LV is swung downward, the cam surface 13D rotates clockwise to contact the roller 91, and the roller between the inner peripheral surface 16C and the cam surface 13D. 91 is clamped. Thereby, the ratchet side outer ring | wheel 16 and the lever member 13 can rotate integrally.
Therefore, as shown in FIG. 9C, if the lever member 13 is further rotated clockwise, the ratchet-side outer ring 16 and the lever member 13 are rotated clockwise while being integrated. That is, the input torque obtained by rotating the lever member 13 is transmitted to the ratchet side outer ring 16.

  When the lever LV is returned from the position below the neutral position N to the neutral position N, the lever member 13 rotates counterclockwise from the state of FIG. The roller 91 escapes clockwise, and the roller 91 is not sandwiched between the cam surface 13D and the inner peripheral surface 16C. Therefore, the lever member 13 rotates toward the neutral position N while the ratchet side outer ring 16 remains stationary. That is, the input torque for returning the lever member 13 is not transmitted to the ratchet side outer ring 16 but is blocked. The lever LV is assisted to operate toward the neutral position N by the urging force of the return spring 95 and is maintained at the neutral position N.

  The operation of raising the lever LV from the neutral position N and returning it from the upper position to the neutral position N is the same as that in the case of the downward swing described above, and thus the description thereof is omitted.

The operation of the brake mechanism 3 when the ratchet side outer ring 16 is rotated by operating the lever LV will be described.
As shown in FIG. 10A, before the ratchet side outer ring 16 rotates, the roller 92 is sandwiched between the inner peripheral surface 11C of the brake side outer ring 11 and the cam surface 18C. Thereby, the reverse input torque from the output gear 21D is interrupted. At this time, the roller 92 is slightly separated from the stepped portion 17 </ b> C of the transmission member 17.
When the ratchet side outer ring 16 rotates, the transmission member 17 also rotates integrally with the ratchet side outer ring 16. As shown in FIG. 10B, when the transmission member 17 is slightly rotated clockwise, the stepped portion 17C and the roller 92 come into contact with each other, and the roller 92 is pushed clockwise so that the inner peripheral surface 11C and the cam surface 18C The clamping of the roller 92 is released, and the brake is released. Thereafter, as shown in FIG. 10C, when the lever LV is lowered as it is, the transmission member 17 further rotates clockwise, and the first protrusion 18D and the first protrusion 18D enter. The stepped portion 17C of the cutout 17A is in contact with the circumferential direction. Due to the engagement between the stepped portion 17C and the first projecting portion 18D, the input torque for lowering the lever LV is transmitted from the transmitting member 17 to the brake side cam 18.

  When the brake cam 18 rotates clockwise, the main shaft 21 is integrated with the brake cam 18, so the main shaft 21 also rotates clockwise. When the lever LV is lowered, if the output gear 21D is applied with a force in a direction to lower the vehicle seat S, the brake cam 18 is also rotated by the force after the brake is released. . When the lever LV is stopped from being lowered and returned to the neutral position N, the brake cam 18 stops when the roller 92 is sandwiched between the inner peripheral surface 11C and the cam surface 18C.

  When the lever LV is swung upward from the neutral position N, the output gear 21D can be rotated by a substantially reverse operation when swung downward.

  In the brake mechanism 3 and the clutch unit 1 that realize the operation as described above, the return spring 95 is covered with the housing 10 at least in the radial direction. It is hard for dust to adhere. Even if the occupant has a string-like belonging, the string-like member is hardly entangled with the return spring 95 because the outer side in the radial direction of the return spring 95 is covered with the housing 10. Therefore, these dusts are prevented from interfering with the operation of the return spring 95, and the operation of returning the lever LV to the neutral position N can be realized stably. As shown in FIG. 2A, the return spring 95 is partially exposed from the operation opening 12C, but the operation opening 12C is recessed when viewed from the outside of the side wall 12B of the cover member 12. Since the recess 12E is formed, dust hardly enters the housing from the operation opening 12C and adheres to the return spring 95, or the return spring 95 is hardly entangled with a string.

  Since the end portion of the return spring 95 is supported by the spring support portion 13G that extends from the lever member 13 and enters the housing 10, dust adheres to the end portion of the return spring 95 with a simple configuration. Can be suppressed. Further, since the member that covers the return spring 95 is the housing 10 that accommodates the rollers 91 and 92, the number of parts is reduced and the clutch unit 1 can be downsized as compared with the case where a member different from the housing 10 is used. In addition, the weight can be reduced.

  Furthermore, since the outer peripheral portion 12A of the cover member 12 is fitted to the outer peripheral portion 11A of the brake-side outer ring 11, the housing 10 is configured so that the outer peripheral portion 11A of the brake-side outer ring 11 is the outer peripheral portion 12A of the cover member 12. It is reinforced by. For this reason, it becomes difficult to deform | transform the brake side outer ring | wheel 11 to radial direction outer side, and can aim at the improvement of a braking force.

  The lever member 13 is not only a member for attaching the lever LV, but also functions as a ratchet cam 13C, a function of holding the return spring 95 by the connecting portion 13E, and both end portions of the return spring 95 by the spring support portion 13G. Therefore, the clutch unit 1 can be made compact and lightweight by reducing the number of parts.

  Looking at the brake mechanism 3, the engagement between the transmission member 17 and the roller 92 is realized by slightly protruding the input side end of the roller 92 from the brake side cam 18. 18 is realized by forming a first protrusion 18D from the main body 18A of the brake cam 18 toward the input side. For this reason, the transmission member 17 can be formed in a flat plate shape, the size (thickness) in the axial direction is small, and the weight can be reduced. Further, since the transmission member 17 has a flat plate shape, it can be manufactured only by blanking the plate material, and thus can be manufactured at low cost.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. About a concrete structure, it can change suitably in the range which does not deviate from the meaning of this invention.

For example, the first movable piece and the second movable piece do not need to be rollers, and the shape is not limited as long as it is a small piece that can be engaged with and detached from the inner circumferential surface and the cam surface of the outer ring, and may be a sphere or a wedge. May be.
In the above embodiment, the ratchet side outer ring is illustrated as the first rotating body, and the ratchet side cam is illustrated as the second rotating body. However, the inner peripheral surface of the outer ring is cam-shaped and the outer peripheral surface of the inner ring is cylindrical. It doesn't matter.

  In the embodiment, the housing 10 has the return spring 95 slightly exposed to the input side. However, the lever member 13 is composed of two parts to reduce the size of the operation opening 12C or to cover the operation opening 12C. For example, a part may be provided so that the input side of the return spring 95 is completely covered. In this way, it is possible to further suppress the dust from adhering to the return spring 95.

  In the above-described embodiment, the brake-side outer ring 11 also serves as the housing 10.

  In the embodiment, the cover member 12 restricts the movement of the roller 91 to the input side, but this restriction may be realized by another component.

  In the embodiment, the lever attachment portion 13A extends to the radially outer side from the outer periphery of the housing 10, but may not extend to the radially outer side. Further, the operation member does not necessarily have a lever shape.

  The 1st opening part and 2nd opening part which are provided in a transmission member do not need to be a notch provided in outer periphery like the said embodiment, and may be a through-hole provided in the inner peripheral side more. The first opening and the second opening may have different shapes.

  Further, the engagement hole 17E does not need to be a through hole as long as the second protrusion 16D can be engaged, and may be a bottomed hole. And the arrangement | positioning may also be a position of radial outside rather than a 1st opening part and a 2nd opening part.

  Further, the brake mechanism and the clutch unit are not only used in the height adjustment mechanism of the vehicle seat S, but can be arbitrarily applied to other devices.

DESCRIPTION OF SYMBOLS 1 Clutch unit 2 Ratchet mechanism 3 Brake mechanism 10 Housing 11 Brake side outer ring 11A Outer peripheral part 11B Side wall 11C Inner peripheral surface 12 Cover member 12A Outer peripheral part 12B Side wall 12C Operation opening 12D Spring locking opening 13 Lever member 13A Lever mounting part 13B Hole 13C Ratchet side cam 13D Cam surface 13E Connection portion 13G Spring support portion 14 Posture restricting member 15 Roller retainer 15B Roller holding portion 15C Roller holding wall 16 Ratchet side outer ring 16A Outer peripheral portion 16B Side wall 16C Inner peripheral surface 16D Second projecting portion 17 Transmission Member 17A Notch 17C Stepped portion 17E Engagement hole 18 Brake cam 18A Main body 18C Cam surface 18D First protrusion 21 Main shaft 21D Output gear 91 Roller 92 Roller 95 Return spring 95B Engagement end L Lever

Claims (6)

A ratchet mechanism that is provided on the input side and transmits / cuts off the input torque due to the swinging motion of the operation member to which the lever is attached, and is provided on the output side, transmits the input torque from the ratchet mechanism to the output shaft, and A clutch unit including a brake mechanism for blocking reverse input torque from the output shaft,
The brake mechanism is used, the number and brake side outer ring, and a brake-side cam does not rotate relative to the brake-side outer race when blocking a reverse input torque from the output shaft with rotatable relative to the brake-side outer race And
The ratchet mechanism is associated with a first rotating body capable of transmitting a rotational force to the brake cam, a second rotating body swingable integrally with the operation member, and the first rotating body and the second rotating body. A movable piece that transmits and cuts off the input torque from the operation member by joining and leaving,
A return spring for returning the operating member to a neutral position;
A housing that covers the movable piece and the return spring at least from the outside in the radial direction ,
The operation member is made of one component and is located in the housing, the second rotating body, a lever mounting portion that is disposed outside the housing and to which the lever is mounted, and the second rotating body. A clutch unit comprising: a connecting portion connecting to the lever mounting portion and penetrating in and out of the housing . 2. The clutch according to claim 1, wherein the housing includes the brake-side outer ring and a cover member that fits on an outer periphery of the brake-side outer ring and covers an input-side side surface of the movable piece. unit. The clutch unit according to claim 2, wherein the cover member regulates movement of the movable piece toward the input side. The clutch unit according to any one of claims 1 to 3, wherein the lever mounting portion extends radially outward from the outer periphery of the housing. The clutch unit according to any one of claims 1 to 4, wherein the return spring is held by the connecting portion. The operation member has a spring support portion that enters the housing on the opposite side of the connection portion across the swing axis.
The clutch unit according to claim 5 , wherein both ends of the return spring are locked to the spring support portion.

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