JP2006288740A - Reclining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reclining device capable of stably obtaining high locking strength. <P>SOLUTION: In the reclining device, a ratchet plate is rotatably stacked on a base plate, internal teeth whose center is the rotation center are formed on the ratchet plate, a pole is arranged on the base plate movably in the radial direction of the addendum circle of the internal teeth, locking is performed by engaging the external teeth of the pole with the internal teeth of the ratchet plate and unlocking is performed by detaching them. Among the external teeth 151 disposed in the width direction of the pole 150, the external teeth 151A disposed at a center part Lc are constituted of a tooth form formed by being negatively profile-shifted compared to the tooth form of the external teeth 151B and 151C disposed at both end parts Ls1 and Ls2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a reclining device that adjusts the angle of a backrest of a vehicle seat. More specifically, the ratchet plate is rotatably overlapped with the base plate, the operation shaft is disposed on the rotation center axis thereof, and the ratchet plate facing the base plate has a circular shape centering on the operation shaft. A concave portion is formed, and inner teeth are formed on the inner peripheral wall surface of the concave portion. Further, a pole having an outer tooth on the front end surface side that can be engaged and disengaged from the radial direction of the tip circle is arranged in the concave portion. On the other hand, the base plate is provided with a guide projection for sliding and guiding the pole in the radial direction, and a cam that can be rotated together with the operation shaft is disposed in the space on the rear end face side of the pole. The cam is urged in a direction that presses the rear end face of the pole and meshes the external teeth of the pole with the internal teeth of the ratchet plate, and with the operation shaft against the urging force of the urging means. When rotating the arm is a release means pole is forcibly moved to the rotation center side of the cam relates to a reclining device for disengaging the outer teeth of the pole from the inner teeth of the ratchet plate.

  Generally, the external teeth of the pole used in this type of reclining device are formed such that teeth having the same shape (same specifications) are aligned on one pitch circle. There are also different sequences as described in. In the configuration described in Patent Document 1, in order to increase the locking strength, the dimension in the width direction of the pole is increased to increase the number of external teeth, and the engagement strength between the external teeth and the internal teeth of the ratchet plate is increased. It is about to try.

When the dimension in the width direction of the pole is increased, the external teeth at both ends of the pole are greatly inclined with respect to the moving direction of the pole, resulting in poor meshing. In order to eliminate the meshing failure, the thickness of the external teeth located at both ends is reduced.
JP 2004-105637 A (FIGS. 4 to 5)

  In this type of reclining device, a heavy load is applied to the pole from the ratchet plate side through its internal teeth in the event of a collision with a vehicle or the like. It is most important to keep the tilt small. In order to minimize the inclination of the pole, in particular, the external teeth on both ends of the pole and the internal teeth of the ratchet plate are engaged with each other without gaps, and the side of the pole is supported firmly over a wide range with a large guide protrusion. Is required.

  For general external teeth in which teeth of the same shape (same specifications) are arranged in an arc, the external teeth at both ends of the pole and the internal teeth of the ratchet plate may mesh without gaps due to processing tolerances, etc. In some cases, it is difficult to keep the pole tilt small.

  On the other hand, in the configuration described in Patent Document 1 in which the dimension in the width direction of the pole is increased to increase the number of external teeth, both end portions that are most advantageous for suppressing the inclination of the pole are obtained although the width of the pole is increased. Since the tooth thickness of the outer teeth is made thinner, the gap between the outer teeth of this portion and the inner teeth of the ratchet plate is large, and the effect of suppressing the inclination of the pole cannot be expected so much. Moreover, by increasing the dimensions of the pole in the width direction, the guide protrusions have to be reduced accordingly, and as a result, the sides of the pole cannot be firmly supported, despite the fact that the pole is wide. There is also a risk of increasing the tilt of the pole.

  Therefore, in any configuration, it is difficult to keep the inclination of the pole small. For this reason, there is a problem in that the engagement allowance is reduced and sufficient lock strength cannot be obtained.

  The present invention solves the above problems, and an object of the present invention is to realize a reclining device that can stably obtain high lock strength.

  In the invention according to claim 1 which solves the above-mentioned problem, a ratchet plate is rotatably stacked on a base plate, an operation shaft is disposed on a rotation center axis thereof, and the ratchet plate is opposed to the base plate. Is formed with a circular recess centered on the operation shaft, and an inner tooth is formed on the inner peripheral wall surface of the recess. Further, the recess engages with the inner tooth from the radial direction of the tip circle. A pole having a removable external tooth on the front end face side is disposed, while the base plate is provided with a guide protrusion for slidingly guiding the pole in the radial direction, and the space on the rear end face side of the pole is provided. A cam that is rotatable together with the operation shaft is arranged, and the biasing means presses the rear end face of the pole so that the external teeth of the pole mesh with the internal teeth of the ratchet plate. When the cam is rotated by the operation shaft against the urging force of the urging means, the release means forces the pawl toward the rotation center of the cam. A reclining device that moves the external teeth of the pole away from the internal teeth of the ratchet plate, and the external teeth disposed in the center of the external teeth disposed in the width direction of the pole are The reclining device is configured with a tooth profile formed by a negative shift compared to the tooth profile of the external teeth disposed at both ends.

  In the present invention, the external teeth disposed in the central portion in the width direction of the pole are configured with a tooth profile formed by negatively shifting compared to the tooth profile of the external teeth disposed at both ends. Therefore, on the pitch circle of the external teeth disposed at both ends, the tooth thickness of the external teeth disposed in the central portion is thin, and the external teeth disposed in the central portion of the pole are ratchet It can mesh without interfering with the internal teeth of the plate. As a result, the external teeth disposed at both ends can be deeply engaged with the internal teeth of the ratchet plate when locked, and no gap is generated between the external teeth and the internal teeth disposed at both ends. In this locked state where both ends are firmly engaged, even if a load is applied to the pole from the ratchet plate via its internal teeth, the inclination of the pole can be kept small, and the meshing margin will not be greatly reduced. .

  According to a second aspect of the present invention, in the reclining device according to the first aspect, in order to increase the strength of the guide protrusion, no concave portion is formed on the back surface side of the guide protrusion on the base plate.

  According to the first aspect of the present invention, the external teeth disposed in the central portion of the pole can mesh without interfering with the internal teeth of the ratchet plate, and as a result, the external teeth disposed at both ends. However, when locked, it can mesh deeply with the inner teeth of the ratchet plate, and no gap is created between them. Therefore, in this locked state, both ends are firmly meshed, and even if a load is applied to the pole from the ratchet plate via its internal teeth, the inclination of the pole can be kept small, and the meshing margin is greatly reduced. No, stable and high lock strength can be obtained.

  According to the second aspect of the present invention, since the concave portion is not formed on the back surface side of the guide projection on the base plate, the strength of the guide projection is high. As a result, there is no deformation of the guide projection, so that the inclination of the pole is small. Stable and high lock strength can be obtained.

  Embodiments of the present invention will be described with reference to FIGS. First, as shown in FIG. 3, in the reclining device of this embodiment, the base plate 100 is attached to the lower arm 201 on the seat cushion side, and the ratchet plate 130 is attached to the upper arm 202 on the seat back side.

  As shown in FIGS. 2 to 5, the disc-shaped ratchet plate 130 is fitted to the disc-shaped base plate 100, so that both are overlapped so as to be relatively rotatable. The cylindrical mounting bracket 205 wraps the base plate 100 and the ratchet plate 130 from the outside, and prohibits the ratchet plate 130 from separating from the base plate 100. Specifically, one end of the mounting bracket 205 is locked to the outer peripheral portion of the base plate 100, and the ratchet plate holding portion 205a on the other end side presses the ratchet plate 130 from the rotation center axis direction.

  A hole 101 and a hole 131 are formed at positions on the rotation center axis of the base plate 100 and the ratchet plate 130, and the operation shaft 120 is inserted into the hole 101 and the hole 131. As shown in FIGS. 3 and 5, a circular recess 132 centered on the operation shaft 120 is formed on the surface of the ratchet plate 130 facing the base plate 100, and the inner peripheral wall surface of the recess 132 has an inner wall. Teeth 133 are engraved.

  As shown in FIGS. 3 and 5, a concave portion 104 is formed on the surface of the base plate 100 facing the concave portion 132 of the ratchet plate 130. As shown in FIG. A pair of guide projections 105, 106 and a pair of guide projections 107, 108 project toward the plate 130.

  The base plate 100 in this embodiment is formed by forging. When the base plate 100 is manufactured from a plate material by using normal press molding instead of forging, as shown in FIG. 9A, a press die (male die) is placed on the back side of the guide protrusions 105, 106, 107, and 108. ) Remains, and thin portions SL are formed in the guide protrusions 105, 106, 107, and 108, and the strength of the guide protrusions 105, 106, 107, and 108 is reduced.

  In this embodiment, the base plate 100 is manufactured by using forging, and at this time, as shown in FIG. 9B, the concave portions are not formed on the back side of the guide protrusions 105, 106, 107 and 108 on the base plate 100. In other words, the strength of the guide protrusions 105, 106, 107, and 108 is increased by forming the guide protrusions 105, 106, 107, and 108 in a solid shape and sufficiently increasing the thickness of the peripheral portion thereof. .

  On the surface of the base plate 100 opposite to the ratchet plate 130 side, a plurality of coupling projections 100a for attaching to the lower arm 201 on the seat cushion side are arranged at equal intervals on the same circumference centered on the hole 101. Has been. On the surface of the ratchet plate 130 opposite to the base plate 100 side, a plurality of coupling protrusions 130 a for mounting on the seat back side upper arm 202 are arranged at equal intervals on the same circumference centered on the hole 131. Has been.

  The pole 140 has outer teeth 141 that can be engaged and disengaged from the radial direction of the tip circle on the inner teeth 133 of the ratchet plate 130 on the front end surface side, and as shown in FIG. 6, the guide surfaces of the guide protrusions 105 and 106 105a and 106a are slidably guided in the direction orthogonal to the rotation center axis of the ratchet plate 130, that is, in the radial direction of the tip circle of the internal teeth 133.

  The pole 150 has the same shape as the pole 140, is sandwiched between the guide surfaces 107a and 108a of the guide protrusions 107 and 108, is slidably guided in the radial direction of the tip circle of the inner tooth 133, and is on the front end surface side. The outer teeth 151 can be engaged with the inner teeth 133 of the ratchet plate 130.

  Here, the external teeth 141 and 151 of the poles 140 and 150 will be described taking the external teeth 151 as an example. As shown in FIG. 1, the external teeth 151 (151A) disposed in the center portion Lc in the width direction of the pole 150 have the tooth shapes of the external teeth 151 (151B, 151C) disposed in both end portions Ls1, Ls2. In comparison, it is configured with a tooth profile formed by a negative dislocation. For this reason, when the tooth thickness of the external teeth 151B and 151C on the pitch circle of the external teeth 151B and 151C is compared with the tooth thickness of the external teeth 151A, the tooth thickness of the external teeth 151A disposed in the central portion Lc The outer teeth 151A can mesh with the inner teeth 133 of the ratchet plate 130 without interfering with each other. By reducing the tooth thickness of the outer teeth 151A, the outer teeth 151B and 151C disposed at the both end portions Ls1 and Ls2 can be deeply engaged with the inner teeth 133 of the ratchet plate 130 when locked, and the outer teeth 151B and 151C are engaged. There is no gap between the inner teeth 133 and the inner teeth 133.

  The number of external teeth 151B and 151C arranged at both ends Ls1 and Ls2 is, for example, about 3 crests, and the number of external teeth 151A arranged at the central portion Lc is, for example, about 19 crests. . The external tooth joint portion between the both end portions Ls1, Ls2 and the center portion Lc is formed so that the tooth bottom is smoothly connected. Further, O1 in FIG. 1 is the center of the pitch circle of the external teeth 151B and 151C.

  A cam 170 that can rotate together with the operation shaft 120 is disposed in the space on the rear end surfaces 146 and 156 side of the poles 140 and 150. That is, as shown in FIG. 3, a cross-sectional oval portion 123 is formed in the intermediate portion of the operation shaft 120, and this cross-sectional oval portion 123 is fitted in the oval hole 171 of the cam 170. As a result, the operation shaft 120 and the cam 170 are fitted in a state where relative rotation is impossible, and the cam 170 rotates together with the operation shaft 120.

  The poles 140 and 150 and the cam 170 are formed to have the same thickness and are disposed on the same plane of the base plate 100. The cam 170 has an inclined cam surface 174b for pressing the rear end surfaces 146 and 156 of the poles 140 and 150 when the cam 170 rotates to mesh the outer teeth 141 and 151 of the poles 140 and 150 with the inner teeth 133 of the ratchet plate 130. , 175b. In order to exert this function, the inclined cam surfaces 174b and 175b are inclined with respect to the contact between the inclined cam surfaces 174b and 175b and the rear end surfaces 146 and 156 of the poles 140 and 150 when the cam 170 rotates in the locking direction. The point is set in a direction away from the rotation center O of the cam 170. For example, if the inclined cam surface 175b in FIG.

  Further, the cam 170 is positioned on the front side in the rotation direction (counterclockwise direction in FIG. 7) of the cam 170 relative to the inclined cam surfaces 174b and 175b, and the outer teeth 141 and 151 of the poles 140 and 150 and the ratchet. When meshing with the internal teeth 133 of the plate 130, support surfaces 174a and 175a are provided at the ends of the rear end surfaces 146 and 156 of the poles 140 and 150 (front portions in the rotation direction when the cam 170 is locked) via a gap. ing. When the counterclockwise load in FIG. 7 is applied from the ratchet plate 130 to the poles 140 and 150 from the ratchet plate 130, the support surfaces 174a and 175a abut against the ends of the rear end surfaces 146 and 156 of the poles 140 and 150. And further tilting of the poles 140 and 150 is prohibited.

  Further, the cam 170 is located on the rear side in the rotation direction when the cam 170 is locked with respect to the inclined cam surfaces 174b and 175b, and between the outer teeth 141 and 151 of the poles 140 and 150 and the inner teeth 133 of the ratchet plate 130. Support surfaces 174c and 175c are provided so as to face the end portions of the rear end surfaces 146 and 156 of the poles 140 and 150 (the rear side portion in the rotation direction when the cam 170 is locked) when engaged. When the clockwise load in FIG. 7 is applied from the ratchet plate 130 to the poles 140 and 150 from the ratchet plate 130, the support surfaces 174c and 175c come into contact with the ends of the rear end surfaces 146 and 156 of the poles 140 and 150. It supports and prohibits further tilting of the poles 140 and 150.

  The detailed structures of the support surfaces 174a, 174c, 175a, 175c and their surroundings will be described using the support surface 175a as an example with reference to FIG. The support surface 175a includes a first inclined surface 175e having a length L1 inclined in the same direction as the inclined cam surface 175b, and a second inclined surface 175f having a length L2 inclined in the opposite direction to the inclined cam surface 175b. At the end portion of the rear end surface 156 of the 150, a first protrusion 150e that can contact the first inclined surface 175e and a second protrusion 150f that can contact the second inclined surface 175f are provided.

  Here, specific examples of the first inclined surface 175e and the second inclined surface 175f will be described. The first inclined surface 175e has an outer peripheral surface formed so that the distance between the part and the rotation center of the cam 170 becomes smaller as the part is in the rotation direction when locked. Conversely, the outer peripheral surface of the second inclined surface 175f is formed so that the distance between the part and the rotation center of the cam 170 increases as the part in the rotation direction when locked.

  Therefore, in the example in which the first inclined surface 175e and the second inclined surface 175f are formed using a part of the arc CT having the radius R passing through the boundary point M between the first inclined surface 175e and the second inclined surface 175f, The first inclined surface 175e above the point M is an inclined surface in a state where the arc CT is inclined counterclockwise (bent state) around the boundary point M, and the second inclined surface below the boundary point M. 175f is an inclined surface in a state where the arc is inclined clockwise around the boundary point M (bent state). The support surfaces 174a, 174c and 175c other than the support surface 175a are also provided with a first inclined surface and a second inclined surface with the same arrangement.

  Cam grooves 144 and 154 are formed on the surface of the poles 140 and 150 on the ratchet plate 130 side (in this embodiment, the cam grooves 144 and 154 are holes penetrating to the surface on the base plate 100 side). . The release plate 180 constituting the release means is disposed so that one surface thereof overlaps with the poles 140 and 150 and the cam 170 and the other surface is in sliding contact with the ratchet plate 130. A hole 181 through which the operation shaft 120 is inserted is formed in the central portion of the release plate 180.

  As shown in FIGS. 6 and 7, the cam 170 has protrusions 176 and 177 protruding toward the ratchet plate 130, and these protrusions 176 and 177 are formed at the edge of the hole 181 of the release plate 180. It is fitted in small slots 182 and 183 extending in the radial direction. For this reason, the cam 170 and the release plate 180 rotate in conjunction with each other.

  Further, as shown in FIGS. 3 and 6, projections 183 and 184 that engage with the cam grooves 144 and 154 are formed at the rotating end portion of the release plate 180 by press molding or the like. The cam grooves 144 and 154 are shaped so that when the release plate 180 rotates in the clockwise direction in FIG. 6, the pawls 140 and 150 are moved toward the rotation center side of the cam 170 by the interaction between the cam grooves 144 and 154 and the protrusions 183 and 184. It is set to move forcibly.

  As shown in FIGS. 6 and 7, the spiral springs 191 and 195 as urging means have inner ends hooked to the hooks 111 and 112 of the base plate 100 and outer ends hooked to the step portions 178 and 179 of the cam 170. The cam 170 is rotated and biased so that the cam 170 pushes the rear end surfaces 146 and 156 of the poles 140 and 150.

  The operation of the reclining device having the above configuration will be described. In the locked state, the urging force of the spiral springs 191 and 195 causes the cam 170 to push the rear end surfaces 146 and 156 of the poles 140 and 150, and the external teeth 141 and 151 of the poles 140 and 150 mesh with the internal teeth 133 of the ratchet plate 130. In this state, the rotation of the ratchet plate (seat back) 130 is prohibited.

  The movement at the time of shifting to the locked state will be described. The cam 170 that receives the urging force of the spiral springs 191 and 195 is a direction in which the external teeth 141 and 151 of the poles 140 and 150 are engaged with the internal teeth 133 of the ratchet plate 130. Rotate first. Accordingly, the inclined cam surfaces 174b and 175b of the cam 170 press the rear end surfaces 146 and 156 of the poles 140 and 150, and the outer teeth 141 and 151 of the poles 140 and 150 mesh with the inner teeth 133 of the ratchet plate 130. Move in the radial direction.

  The movement at this time will be described by taking the periphery of the support surface 175a of the cam 170 as an example. When the pole 150 moves, the first protrusion 150e, which is a part of the pole 150, also moves in the same direction and moves away from the rotation center O of the cam 170, but the first inclination of the cam 170 from the first protrusion 150e of the pole 150. When the surface 175e is viewed, the first inclined surface 175e of the cam 170 approaches the first protrusion 150e of the pole 150 as the cam 170 rotates.

  For this reason, it can avoid that the clearance gap between the 1st protrusion 150e of the pole 150 and the 1st inclined surface 175e of the cam 170 becomes large too much at the time of a lock | rock. Therefore, the lock strength is not greatly reduced, and a high lock strength can be obtained stably.

  In a locked state in which the external teeth 151 of the pole 150 and the internal teeth 133 of the ratchet plate 130 are engaged, when a load is applied from the ratchet plate 130 to the pole 150 due to a vehicle collision or the like, the pole 150 is slightly inclined and its first protrusion The portion 150e contacts the first inclined surface 175e of the cam 170, and the second protrusion 150f contacts the second inclined surface 175f of the cam 170. Therefore, the pole 150 is supported by a total of three points including the inclined cam surface 175b and the first and second inclined surfaces 175e and 175f of the cam 170.

  When a load is applied from the ratchet plate 130 to the pole 150, the contact pressure between the first inclined surface 175e of the cam 170 and the first protrusion 150e of the pole 150 causes a contact pressure in the common normal direction on the contact surface. Works. Therefore, by providing the first inclined surface 175e inclined in the same direction as the inclined cam surface 175b, the component force F1 (force that generates the clockwise torque in FIG. 8) that pushes the cam 170 back in the unlocking direction. ) Also acts on the cam 170.

  On the other hand, the cam 170 is provided with a second inclined surface 175f inclined in the opposite direction to the inclined cam surface 175b. In the contact surface between the second inclined surface 175f of the cam 170 and the second protrusion 150f of the pole 150, A component force F <b> 2 (a force that generates a counterclockwise torque in FIG. 8) that tries to rotate the cam 170 in the locking direction also acts on the cam 170. Therefore, the force F1 that is caused by providing the first inclined surface 175e and tries to push the cam 170 back in the unlocking direction is eliminated or reduced by the reverse force F2 generated by the presence of the second inclined surface 175f. Thus, the lock is not released, and a high lock strength can be obtained from this point.

  Note that there may be a case where the second inclined surface 175f of the cam 170 and the second protrusion 150f of the pole 150 do not come into contact with each other at the time of locking. The cam 170 stops when 150f and the second inclined surface 175f of the cam 170 come into contact with each other. This is because, when the second projecting portion 150f of the pole 150 and the second inclined surface 175f of the cam 170 are in contact with each other, the presence of the second inclined surface 175f causes a component force F2 to rotate the cam 170 in the locking direction. This is because it occurs.

  When the operation shaft 120 is rotated clockwise in FIG. 7 against the biasing force of the spiral springs 191 and 195 in the locked state, and the cam 170 is also rotated clockwise, the rear end surfaces of the poles 140 and 150 of the cam 170 are rotated. 146 and 156 are released, the projections 183 and 184 of the release plate 180 are in sliding contact with the inclined wall surfaces of the cam grooves 144 and 154 of the poles 140 and 150, and the external teeth 141 and 151 of the poles 140 and 150 are ratchet. The poles 140 and 150 retreat in a direction away from the inner teeth 133 of the plate 130, the meshing between the outer teeth 141 and 151 of the poles 140 and 150 and the inner teeth 133 of the ratchet plate 130 is released, and the ratchet plate (seat back) 130 can be tilted (unlocked state).

  When the seat back is tilted to a desired angle and the operation force to the operation shaft 120 is released, the cam 170 pushes the rear end surfaces 146 and 156 of the poles 140 and 150 by the urging force of the spiral springs 191 and 195, The 150 external teeth 141 and 151 mesh with the internal teeth 133 of the ratchet plate 130 again, and the ratchet plate (seat back) 130 returns to a state in which rotation is prohibited.

According to the configuration of such an embodiment, the following effects can be obtained.
(1) The external teeth 141 and 151 disposed at the center of the poles 140 and 150 can mesh with the internal teeth 133 of the ratchet plate 130 without interfering with each other, and as a result, the external teeth disposed at both ends. The teeth 141 and 151 can be deeply engaged with the inner teeth 133 of the ratchet plate 130 at the time of locking, and there is no gap between the outer teeth 141 and 151 and the inner teeth 133 disposed at both ends. Thus, in the locked state where both ends are firmly engaged, even if a load is applied to the poles 140 and 150 via the inner teeth 133 from the ratchet plate 130 side, the poles 140 and 150 are difficult to tilt, and the tilt is kept small. Thus, the engagement allowance is not greatly reduced, and a high lock strength can be obtained stably.

 (2) The guide protrusions 105, 106, 107, and 108 are formed in a solid shape so as not to be formed on the back surface side of the guide protrusions 105, 106, 107, and 108 on the base plate 100. The strength of the protrusions 105, 106, 107, and 108 can be increased. As a result, the guide protrusions 105, 106, 107, and 108 are not deformed or damaged, and the poles 140 and 150 are not easily tilted, thereby increasing the lock strength. Can do.

 (3) The gap between the first protrusions of the poles 140 and 150 and the first inclined surface of the cam 170 at the time of locking can be reduced, and the inclination of the poles 140 and 150 can also be reduced. Therefore, the lock strength is not greatly reduced, and a high lock strength can be obtained stably. In addition, when a load is applied from the ratchet plate 130 to the poles 140 and 150, a component force that pushes the cam 170 back in the unlocking direction also acts on the cam 170. However, the cam 170 is opposite to the inclined cam surface. A second inclined surface that is inclined in the direction is also provided, whereby a component force that causes the cam 170 to rotate in the locking direction also acts on the cam 170. Therefore, the force to push the cam 170 back in the unlocking direction caused by the provision of the first inclined surface is eliminated or reduced by the reverse force generated by the presence of the second inclined surface, and the lock is released. In this respect, high lock strength can be obtained.

 (4) In particular, before and after the meshing position between the external teeth 141 and 151 of the poles 140 and 150 and the internal teeth 133 of the ratchet plate 130, the first inclined surface 175e of the cam 170 and the first protrusions of the poles 140 and 150 If the shapes of the support surfaces (first inclined surface and second inclined surface) 174a, 174c, 175a, 175c and inclined cam surfaces 174b, 175b of the cam 170 are set so that the gap of the cam 170 is constant, they are meshed by component tolerance. Even if the position deviates from the normal target position, the lock strength does not vary greatly.

 (5) Protrusions 183 and 184 that engage with the cam grooves 144 and 154 are formed at the rotation end of the release plate 180, and the pawls 140 and 150 are moved by the interaction between the cam grooves 144 and 154 and the protrusions 183 and 184. Since the engaging portion to the cam grooves 144 and 154 is formed integrally with the release plate 180 by forcibly moving the cam 170 toward the rotation center side, the configuration of this portion can be simplified, Since the release plate can be molded at low cost by press molding, the cost of the apparatus can be reduced.

 (6) The meshing positions of the external teeth 141 and 151 of the poles 140 and 150 and the internal teeth 133 of the ratchet plate 130 and the contact positions of the side walls of the cam grooves 144 and 154 and the projections 183 and 184 of the release plate 180 are Since the cams 170 are positioned on substantially the same plane with respect to the rotation center axis direction of the cam 170, when the pawls 140 and 150 are moved using the release plate 180 (unlocking operation), the pawls 140 and 150 are rotated by the ratchet plate 130. Since no force is generated in the direction of rising from the plane, the unlocking feeling is good.

  The present invention is not limited to the above embodiment. For example, the shape and the like of the support surfaces 174a, 174c, 175a, 175c and the inclined cam surfaces 174b, 175b of the cam 170 are not limited to those of the above-described embodiment, for example, the first and second inclined surfaces are not provided. In addition, a surface whose peripheral shape is an arc centered on the rotation center of the cam 170 may be used as the support surfaces 174a, 174c, 175a, and 175c. In this case, the number of protrusions on the poles 140 and 150 may be one corresponding to the support surfaces 174a, 174c, 175a, and 175c.

  Further, as a method of attaching the apparatus, the ratchet plate 130 may be attached to the seat cushion side, and the base plate 100 may be attached to the seat back side. The number of poles (140, 150) may be one or three or more, and the biasing of the cam 170 is not limited to the method using the spiral springs 191, 195.

FIG. 8 is a detailed view of the pole in FIG. 7. It is a figure which shows the external appearance of the reclining apparatus of this example. FIG. 3 is a cross-sectional view taken along a cutting line CC in FIG. 2. FIG. 3 is a rear view of FIG. 2. FIG. 3 is a cross-sectional view taken along a cutting line DD in FIG. 2. It is sectional drawing in the cutting line EE of FIG. It is the figure which removed the release plate of FIG. It is an enlarged view of the principal part in FIG. It is sectional drawing of a guide protrusion.

Explanation of symbols

100 Base plate 105 to 108 Guide protrusion 120 Operation shaft 130 Ratchet plate 133 Internal tooth 140, 150 Pole 141, 151 External tooth 144, 154 Cam groove 170 Cam 174a, 174c, 175a, 175c Support surface 180 Release plate

Claims (2)

A ratchet plate is rotatably overlapped with the base plate, an operation shaft is disposed on the rotation center axis thereof, and a circular recess centered on the operation shaft is formed on a surface of the ratchet plate facing the base plate. And an inner tooth is formed on the inner peripheral wall surface of the recess, and the recess further includes a pole having outer teeth on the front end face side that can be engaged and disengaged from the radial direction of the tip circle of the inner tooth. On the other hand, the base plate is provided with a guide projection for slidingly guiding the pole in the radial direction, and a cam that is rotatable together with the operation shaft is arranged in the space on the rear end face side of the pole. The urging means urges the cam in a direction that presses the rear end surface of the pole and meshes the outer teeth of the pole with the inner teeth of the ratchet plate. When rotating the cam with the operation shaft against the urging force, the release means forcibly moves the pole toward the rotation center of the cam, and the external teeth of the pole are moved to the ratchet plate. A reclining device for separating from an internal tooth,
Of the external teeth disposed in the width direction on the pole, the external teeth disposed in the center portion are formed by shifting negatively compared to the external tooth shapes disposed at both ends. A reclining device that is configured.   The reclining device according to claim 1, wherein a recess is not formed on a back surface side of the guide protrusion on the base plate.

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