JP4683967B2 - Reclining device - Google Patents

Description

  The present invention relates to a reclining device mounted on a vehicle seat or the like, and in particular, a neutral position return function in which a forward-turned seat back is returned and fixed to a preset position in an inclination angle adjustment range by a simple operation. It is related with the reclining apparatus provided with.

  Conventionally, a wide variety of reclining devices have been proposed as a reclining device installed in a vehicle seat or the like, but for the purpose of getting on and off the rear seat in a coupe type two-door car or a minivan type car. In addition, the seat back of the front seat is largely moved forward, and the seat back is automatically returned and fixed to a preset position (neutral position) simply by raising the seat back after getting on and off the rear seat. The reclining apparatus provided with is put into practical use.

  As a reclining device having the neutral position return function, for example, a device described in Patent Document 1 is known. In the device described in Patent Document 1, a sector plate in which external sector gears are formed is fixed to a backrest-side rotating bracket, and a lock plate in which lock gears are formed is fixed to a seat-side fixing bracket. A memory plate is disposed to prevent engagement with the lock gear under certain conditions. Then, by the action of the memory plate, the seat back is returned and fixed to a preset neutral position only by raising the seat back that has been tilted forward.

  Here, what is called a round reclining device has been put to practical use as a reclining device that can be easily attached to a seat and is reduced in size and weight. In this round reclining device, a substantially disc-shaped base plate and a substantially disc-shaped gear plate are combined facing each other, and a lock mechanism is arranged in the internal space facing both plates, with the center shaft as a fulcrum. Both plates are relatively rotated and adjusted and fixed.

  As a specific configuration of the round reclining device, for example, one described in Patent Document 2 is known. In addition to the above-described components, the device described in Patent Document 2 has two pegs (protrusions) protruding in the axial direction on a follower (lock gear), and a locking mechanism within a predetermined range by one peg. Is held at the disengagement position, and the unlocking is controlled by a thin plate having the other peg and a stepped circular track (guide hole). That is, in the seat where the device is mounted, if the seat back is moved forward when getting on and off the rear seat of the vehicle, the lock mechanism is held in the disengaged position even if the operation of the operation member is released, and the When the back is raised, the seat back is fixed back to the foremost end of the adjustment range (the most upright position where the seat back can be fixed).

  Then, a function for returning and fixing to the position within the adjustment range is added to the round reclining device as described above, and when the seat back is tilted backward from the forward tilt position, it is automatically returned to the original adjustment angle position before tilting. As a device provided with a function (full memory function) that can be used, there is a reclining device described in Patent Document 3. The reclining device includes a first side plate (disk-shaped plate), a second side plate (disk-shaped plate), and a ring having a pair of internal teeth, and the space between the ring teeth and the first side plate. And a mechanism M (ordinary angle adjusting mechanism) that is locked and unlocked at the first position and a first position that is locked and unlocked between the tooth of the ring and the second side plate and that stores the adjustment position in cooperation with the transverse plate. 2 mechanisms (full memory mechanism). That is, the round reclining device described in Patent Document 3 has a mechanism M for adjusting a normal reclining angle and a second mechanism that performs a full memory function, and angle adjustment in a normal reclining device. It is the structure which combined the mechanism twice.

JP-A-2-177908 Japanese Patent No. 3343039 JP-A-8-300990

  The reclining device described in Patent Document 1 includes a sector plate in which external sector gears are formed, a lock plate in which lock gears are formed, and a memory that prevents engagement between the sector gears and the lock gears under certain conditions. The neutral position return function consisting of a plate is adopted. For this reason, the neutral position return to the round reclining device in which a substantially disc-shaped base plate and a substantially disc-shaped gear plate are combined facing each other and a lock mechanism is provided in the internal space facing both plates. It was difficult to incorporate functions.

  Further, the round reclining device described in Patent Document 2 includes a follower (lock gear) and a thin plate, and two pegs (projections) are formed on the follower, and a lock mechanism is formed by one peg (projection). It is held in the disengaged position, and unlocking is controlled by the other peg (projection) and thin plate. For this reason, in this apparatus, the forward movement of the seat back is maintained even if the operation means is released, but when the seat back is raised, the seat back is returned and fixed to the frontmost position of the adjustment range. The neutral position return function was not provided, and the convenience was insufficient.

  The round reclining device described in Patent Document 3 has a more convenient full memory function, but a mechanism M for performing normal angle adjustment and a second function that performs the full memory function. Therefore, there is an inconvenience that the structure is doubled and the structure becomes complicated and the structure is expensive due to the double combination of the angle adjusting mechanisms.

  The present invention eliminates the above-mentioned difficulties and inconveniences, and is small and lightweight with a neutral position return function in which the seat back is automatically returned and fixed to a preset neutral position when a forward-turned seat back is caused. An object of the present invention is to provide a simplified round reclining device.

  In order to achieve the above object, the invention according to claim 1 is a substantially disk-shaped base plate fixed to either the seat cushion side or the seat back side of the seat, and the base plate is assembled so as to be rotatable face to face. A substantially disc-shaped gear plate having internal teeth, a plurality of lock gears having outer teeth that are guided and assembled to the base plate so as to be movable only in the radial direction and can mesh with the internal teeth of the gear plate; A cam that controls the outward movement in the radial direction and meshes the lock gear with the internal teeth of the gear plate, a spring that rotates and biases the cam in the direction that meshes the lock gear with the internal teeth, and the cam are integrated. Lever base that engages with the protrusions protruding on the lock gear and controls the movement of the lock gear radially inward, and the base A center shaft that is inserted through substantially the center of the rate and gear plate and that can rotate integrally with the cam; and an operation member that is connected to the center shaft and capable of rotating the center shaft against the biasing force of the spring; In a reclining device comprising: a locking portion provided on the gear plate; and a substantially disc shape centered on a center shaft, and having at least one notch portion locked on the locking portion on an outer peripheral edge. The locking portion is rotatable with respect to the gear plate within a certain range movable within the notch, and restricts the lock gear from moving radially outward by the abutment of the lock gear protrusion inside the disk. A memory plate in which a long hole having a substantially arc-shaped guide portion around the center shaft as a part of the periphery is formed, and a spring for urging the memory plate And when the seat back is in the most upright position from the forward position, the projection of the lock gear that rotates relative to the memory plate is within the angular range of the guide portion to form a lock-free range, When the back is at the last tilted position from the most upright position, the lock gear protrusion is in the range that does not contact the memory plate inside the elongated hole to form an adjustment range, and the spring member has the lock gear protrusion from the guide portion. The memory plate is urged to rotate in the direction of disengagement, and the memory plate is within the predetermined range with respect to the gear plate when the seat back is tilted backward with the projection of the lock gear in contact with the guide portion. In the case where it is possible to rotate, it is possible to rotate integrally with the base plate against the urging force of the spring member.

  The invention according to claim 2 is the reclining device according to claim 1, wherein the gear plate is formed in a substantially bowl shape having a stepped step portion, and the inner teeth are formed on the inner periphery of the opening. The first step portion, the second step portion having a smaller circumferential radius than the first step portion, and being in sliding contact with the outer peripheral edge of the lever plate; and the memory plate having a smaller circumferential radius than the second step portion. And a third step portion that is in sliding contact with the outer peripheral edge of the first and second outer peripheral edges, and the spring member is disposed between the memory plate and the gear plate.

  According to a third aspect of the present invention, there is provided a substantially disk-shaped base plate fixed to either the seat cushion side or the seat back side of the seat, and an approximately tooth having an internal tooth that is assembled to the base plate so as to be rotatable face to face. A disk-shaped gear plate, a plurality of lock gears that are guided and assembled to the base plate so as to be movable only in the radial direction, and have external teeth that can mesh with the internal teeth of the gear plate; and A cam that controls movement and meshes the lock gear with the internal teeth of the gear plate, a spring that rotates and biases the cam in a direction that meshes the lock gear with the internal teeth, and rotates integrally with the cam and A lever plate that engages with the projecting projection and controls the movement of the lock gear inward in the radial direction, a base plate, and a gear plate A recliner comprising: a center shaft that is inserted substantially through the center of the shaft and rotatable integrally with the cam; and an operation member that is connected to the center shaft and capable of rotating the center shaft against the biasing force of the spring. In the apparatus, the engaging portion provided on the gear plate and a substantially ring shape centering on a center shaft, and having at least one notch portion engaging with the engaging portion on an outer peripheral edge, A center shaft that can be rotated with respect to the gear plate within a certain range in which the stop portion is movable within the notch portion, and that restricts the lock gear from moving radially outward by the contact of the protrusion of the lock gear on the inner peripheral edge. A memory plate having a substantially arc-shaped guide portion at the center, and a spring member that urges the memory plate to rotate, and the seat back is in the upright position from the forward position. When the seat back is at the most tilted position from the most upright position, the lock gear protrusion that rotates relative to the memory plate is in the angular range of the guide portion to form a lock-free range. The protrusion is in a range where it does not contact the memory plate and forms an adjustment range, and the spring member urges the memory plate to rotate in a direction in which the protrusion of the lock gear disengages from the guide portion, and the memory plate When the seat back is tilted backward with the projection of the lock gear in contact with the guide portion, if the seat back can rotate within the predetermined range, it is integrated with the base plate against the biasing force of the spring member. It can be rotated automatically.

  The invention according to claim 4 is the reclining device according to claim 3, wherein the gear plate is formed in a substantially bowl shape having a stepped step portion, and the inner teeth are formed in the inner periphery of the opening. The first step portion, the second step portion having a smaller circumferential radius than the first step portion, and being in sliding contact with the outer peripheral edge of the lever plate; and the memory plate having a smaller circumferential radius than the second step portion. A third step portion slidably in contact with the outer peripheral edge of the spring member, and the spring member is bent in a direction opposite to the winding direction at the terminal outside the spiral, and the terminal on the center side is in the same direction as the winding. A spiral spring with a bent shape, the outer end is locked to a hook-shaped hook protruding from the inner periphery of the memory plate, and the center end protrudes from the bottom of the gear plate And that the spiral spring is And it is disposed in the third step portion, the features.

  The invention according to claim 5 is the reclining device according to one of claims 1 to 4, wherein the gear plate is provided with an arc portion in which no internal teeth are formed. Is formed to be higher than the inner teeth, and an end portion of the guide portion provided on the memory plate is provided with an inclined portion inclined outward in the radial direction, When the seat back is tilted forward within the lock-free range, the lock gear protrusion is moved in the radial center direction by the inclined portion after the outer teeth of the lock gear ride on the arc portion, and is guided and abutted on the guide portion. And features.

  The invention according to claim 6 is the reclining device according to one of claims 1 to 5, wherein a peripheral edge reaching the end of the guide portion is an arc of the guide portion centered on the center shaft. It is characterized by overhanging in the center direction.

  According to the first aspect of the present invention, the neutral position return function is realized by a spring member that constantly urges the memory plate and the memory plate in the direction in which the seat back is tilted backward with respect to the gear plate. Further, the neutral position return function can be easily incorporated into the round reclining device. The seat back that has returned to the neutral position can be easily seated thereafter, and the reclining device can be readjusted from the neutral position to the original adjustment position or a desired adjustment position with a slight adjustment width, which is convenient.

  According to the second aspect of the present invention, the gear plate is formed in a substantially bowl shape having a stepped step portion, and a lever plate and a memory plate are slidably fitted into the step portion, thereby having functions separated from each other. Since it can be put together into a layered structure and the spring member is also housed in the round reclining device, a small and simple structure can be realized.

  According to the third aspect of the present invention, the neutral position return function is realized by a spring member that constantly urges the memory plate and the memory plate in a direction in which the seat back is tilted backward with respect to the gear plate. Further, the neutral position return function can be easily incorporated into the round reclining device. The seat back that has returned to the neutral position can be easily seated thereafter, and the reclining device can be readjusted from the neutral position to the original adjustment position or a desired adjustment position with a slight adjustment width, which is convenient.

  According to a fourth aspect of the present invention, the gear plate is formed in a substantially bowl shape having a stepped step portion, and the lever plate and the memory plate are slidably fitted into the step portion, thereby having functions separated from each other. Since it can be put together into a layered structure and the spring member is also housed in the round reclining device, a small and simple structure can be realized. The spring member is a spiral spring having a shape in which the terminal outside the spiral is folded back in the direction opposite to the winding direction and the terminal on the center side is bent in the same direction as the winding, and the spring member is placed inside the hollow memory plate. Since the arrangement can be made, the space where the spring member is arranged in the axial direction of the center shaft can be reduced, and the size can be reduced.

  According to the fifth aspect of the present invention, the guide plate provided on the memory plate is provided on the inner periphery of the gear plate on which the inner teeth are formed, with a circular arc portion that is higher than the inner teeth on which the inner teeth are not formed. When the seat back is tilted forward within the lock-free range by providing an inclined portion that is inclined outward in the radial direction at the end of the lock gear, after the lock gear outer teeth ride on the arc portion, Is moved in the radial center direction by the inclined portion and guided to the guide portion. With such a configuration, the engagement between the lock gear and the gear plate near the most upright position can be ensured.

  According to a sixth aspect of the present invention, the memory plate is rotated with respect to the gear plate by projecting the peripheral edge reaching the end of the guide portion in the center direction rather than the arc of the guide portion centered on the center shaft. The memory plate is prevented from being rotated by the gear plate within a certain range. This is because if the memory plate rotates without friction between the notch of the memory plate and the locking portion of the gear plate due to friction between the peripheral edge of the memory plate and the gear plate, the external teeth of the lock will be correspondingly removed from the gear plate. Since the position of meshing with the internal teeth deviates from the neutral position, the extension of the guide portion provides resistance to the rotation of the memory plate, and until the lock projection is released from the guide portion, the notch of the memory plate and the gear plate The locking portion is brought into contact.

  FIG. 1 is a side view showing a state in which a reclining device 105 according to the present invention is attached to a seat 100, and the seat 100 includes a seat cushion 101 and a seat back 102. In the reclining device 105, a substantially disc-shaped base plate 1 and a substantially disc-shaped gear plate 2 which will be described later are combined face-to-face, the outer shape is round, one plate is fixed to the lower bracket 103, and the other The plate is fixed to the upper bracket 104. A center shaft 106 is provided at the center of the reclining device 105, and 107 is an operation lever having one end attached to the center shaft 106.

  The lower end portion of the lower bracket 103 is attached to the rear end portion of the seat cushion 101, and the upper end portion of the upper bracket 104 is attached to the lower end portion of the seat back 102. When the reclining device 105 is operated by the operation lever 107, the inclination angle of the seat back 102 can be arbitrarily adjusted and fixed within the adjustment range a from the most upright position A to the most upright position D in FIG. In the lock-free range b at the forward position B, the seat back 102 is not locked even if the operation of the operation lever 107 is released.

  Note that the position indicated by C in FIG. 1 is a neutral position that is automatically returned and fixed when the seat back 102 is raised from the forward-turned state to the backward-tilt direction, and is the most used at the time of sitting in the adjustment range a. Positions that are likely to be set are set in advance. For this reason, the neutral position C is easier to sit than the most upright position A, and the seat back to the original adjustment position or a desired adjustment position locked before the seat back is moved forward with a slight adjustment width. Can be readjusted.

  Next, a detailed configuration of the reclining device 105 will be described with reference to FIGS. The reclining device 105 has a substantially disk-shaped base plate 1 and a substantially disk-shaped gear plate 2 combined face to face to form a round shape, and a center shaft 106 is inserted into the center of the reclining device 105. The gear plate 2 can rotate relative to the center shaft 106. Further, a ring member 3 is disposed on the circular outer peripheral edge of the reclining device 105, and the circular outer peripheral joining portion between the base plate 1 and the gear plate 2 is slidably contacted by the crimped ring member 3 so as to be relatively rotatable. Is retained.

  In addition, a cavity (space) 4 is provided at a joint portion between the base plate 1 and the gear plate 2, and two lock gears 5, 5, a central cam 6, and two spiral springs are provided in the cavity 4. A well-known lock mechanism composed of 7, 7 and lever plate 8 is accommodated. Similarly, the cavity 4 also accommodates members constituting a neutral position return mechanism including the memory plate 9 and the coil spring 10 which are the main features of the present invention.

  A plurality of circular protrusions 17 and 27 are formed on the outer surfaces of the base plate 1 and the gear plate 2 (surfaces opposite to the mating surfaces), and the base plate 1 is attached to the lower bracket 103 by the circular protrusions 17. The gear plate 2 is attached to the upper bracket 104 by the circular protrusion 27. For this reason, when the relative rotation and the relative angle between the base plate 1 and the gear plate 2 are fixed around the center shaft 106 of the reclining device 105, the relative rotational positions of the lower bracket 103 and the upper bracket 104 are adjusted and fixed. The inclination angle of the seat back 102 is adjusted and fixed to the seat cushion 101.

  The inner surface of the base plate 1 (the mating surface with the gear plate 2) has a substantially bowl shape having concentric steps, and a hole 1a through which the center shaft 106 is inserted is provided at the center. . Also, referring to FIG. 3, a pair of guide portions 50a, 50a including a protrusion 11 and a protrusion 12 are integrally formed on the inner surface of the base plate 1 by press working or the like. Both guide portions 50a are provided at symmetrical positions with respect to the hole 1a, and the opposing surfaces 11a, 12a of the projections 11, 12 are set in parallel to each other, and the guide portions 50a The accommodated lock gears 5 and 5 are slidable in the radial direction of the base plate 1 in a state where the lock gears 5 and 5 are in sliding contact with the surfaces 11a and 12a.

  The lock gear 5 accommodated in the guide portion 50a has parallel side walls facing the opposing surfaces 11a and 12a of the protrusions 11 and 12, and has one end in the radial direction that slides within the guide portion 50a. External teeth 51 are formed, and a pressing portion 5a that changes in a curved shape is formed at the other end in the center direction of the base plate 1 on the opposite side. A guide projection 52 is integrally formed on the surface of the gear plate 2 facing the base plate 1 in which the lock gear 5 is slidably fitted in the guide portion 50a.

  A cam 6 is disposed at substantially the center of the base plate 1 so as to be interposed between the lock gears 5 and 5. The cam 6 has a substantially plate shape and has a square hole 61 into which the center shaft 106 is fitted and inserted at the center, and is rotated integrally with the center shaft 106 in accordance with an operation by the operation lever 107. A pair of cam surfaces 6a and 6a are formed at rotationally symmetrical positions around the square hole 61 of the cam 6, and the cam surfaces 6a and 6a are rotated by the rotation of the cam 6. The pressing portions 5 a and 5 a are pressed, and the lock gears 5 and 5 are moved outward in the radial direction of the base plate 1.

  The cam 6 is integrally formed with a pair of hook engaging portions 6b, 6b adjacent to the cam surfaces 6a, 6a, and the spiral springs 7, 7 are locked. The center of the spiral spring 7, which is the opposite end where the spiral spring 7 is locked to the hook engaging portion 6 b, is locked to the meniscus 13 formed integrally with the base plate 1, and the spiral spring 7 is The cam 6 is urged so as to rotate in the direction in which the lock gear 5 pushes radially outward (clockwise in FIG. 3). The cam 6 has a pair of cylindrical protrusions 62 and 62 projecting in the direction of the gear plate 2 at rotationally symmetric positions around the square hole 61, and is integrated with a lever plate 8 described later. It is assembled to rotate.

  A circular lever plate 8 is placed so as to sandwich the lock gears 5 and 5, the cam 6 and the spiral springs 7 and 7 placed on the base plate from the base plate 2 in the axial direction. The lever plate 8 has a circular hole through which the center shaft 106 is inserted at the center, and the columnar projections 62 and 62 of the cam 6 are engaged with the engagement holes 8a and 8a of the lever plate 8 so that the cam 6 and the lever plate 8 are formed to operate integrally by this engagement.

  The lever plate 8 is provided with a pair of cam holes 81, 81 at rotationally symmetrical positions around the center shaft 106, and guide holes 52 provided on the lock gear 5 are provided in the cam holes 81, 81. Each is loosely fitted. Then, the periphery of the cam hole 81 and the protrusion 52 come into contact with each other by the rotation of the lever plate 8, and the lock gear 5 can be moved toward the radial center by pulling the protrusion 52 toward the radial center. . Therefore, the lock gears 5 and 5 and the cam 6 are rotated in conjunction with the center shaft 106.

  The above-described components are arranged in an axial direction in the cavity 4. The gear plate 2 has a substantially disk-like outer shape and is provided with a hole 2a through which the center shaft 106 is inserted at the center thereof. The inner teeth 21 and the arc portion 22 are formed on the inner periphery of the inner surface facing the base plate 1. The first step portion 23 is provided with a second step portion 24 and a third step portion 25 formed therein in a step-like manner in the axial direction. The first step portion 23 of the gear plate 2 is fitted to the outer shape of the base plate 1, and the outer teeth 51 are engaged with the inner teeth 21 of the gear plate 2 as the lock gears 5 and 5 slide in the radial direction. The position in the axial direction is set so that mating and unmating is performed.

  When the operation lever 107 is not operated, the cam 6 and the lever plate 8 are integrally rotated by the spiral spring 7, and the external teeth 51 of the lock gear 5 are engaged with the internal teeth 21 of the gear plate 2, The reclining device 105 is locked. In this state, when the operation lever 107 is operated against the urging force of the spiral spring 7, the cam 6 and the lever plate 8 rotate together (rotate counterclockwise in FIG. 3), and the lock gear 5 by the cam 6 is rotated. Is released, and the projection 52 of the lock gear 5 is guided by the guide hole 81 of the lever plate 8 so that the lock gear 5 is moved in the direction of the center shaft 106. Then, the engagement between the external teeth 51 of the lock gear 5 and the internal teeth 21 of the gear plate 2 is released, and the reclining device 105 becomes adjustable from the locked state.

  Note that the lock mechanism constituted by the lock gear 5, the cam 6, the lever plate 8 and the like described above is a known lock mechanism, and its locking and unlocking operations are also known. Further, when the external teeth 51 of the lock gear 5 are in a position where they abut against the arc portion 22 of the gear plate 2, the reclining device 105 is not locked, and in this state, the seat back 102 is brought into the lock-free range b in FIG. The corresponding state is realized.

  Next, the memory plate 9 and the coil spring 10 which are main components of the neutral position return mechanism will be described. The memory plate 9 is a substantially disk-shaped plate material, and the coil spring 10 is a spring member that biases the memory plate 9. As shown in FIG. 4, the memory plate 9 has a circular hole 91 through which the center shaft 106 is rotatably inserted in the center, and a pair of substantially arcuate shapes disposed at rotationally symmetric positions around the circular hole 91. A long hole 92 is provided. In addition, two notches 93 are provided on the outer peripheral edge at an appropriate interval, and a hole 94 is formed between the circular hole 91 and one elongated hole 92.

  As shown in FIG. 4, the long hole 92 of the memory plate is composed of a wide portion 92a and a narrow portion 92b, and the seat back is tilted backward at a substantially arcuate peripheral edge on the radially outer side of the wide portion 92a (illustrated). (A counterclockwise direction) is projected toward the central direction to form a guide portion 92d, which forms the narrow portion 92b. A projection 52 of the lock gear 5 is loosely fitted in the elongated hole 92 so that the radial operation of the lock gear 5 can be guided. The second step portion of the gear plate 2 is formed in the notches 93 and 93. A stopper 25a formed projecting in the center direction on 25 is loosely fitted, and the range of relative rotation of the memory plate 9 relative to the gear plate 2 is restricted. In this embodiment, since the seat back and the gear plate 2 rotate integrally, the guide portion 92d is positioned in a direction in which the seat back tilts backward with respect to the wide portion 92a. However, the seat back and the base plate 1 are integrated. In the case of rotation, the apparent shape does not change, but the seat back is positioned in the forward tilting direction.

  The wide portion 92a has substantially the same angular width corresponding to the adjustment range a shown in FIG. 1, and the narrow portion 92b also has substantially the same angular width corresponding to the free width b. When the protrusion 52 of the lock gear 5 is positioned on the wide portion 92a, the lock gear 5 is prevented from coming into contact with the substantially arc-shaped peripheral edge of the wide portion 92a. 2 can be moved without any trouble in the radial direction. When the projection 52 of the lock gear 5 is located in the narrow portion 92b, the lock gear 5 can be moved in the radial direction of the gear plate 2 by the guide portion 92d regardless of the position of the cam hole 81 of the lever plate 8. The outer teeth 52 of the lock gear 5 are prevented from engaging with the inner teeth 21 of the gear plate 2.

  The coil spring 10 is a torsion coil spring that rotationally biases the memory plate 9 in a direction in which the protrusion 52 of the lock gear 5 is disengaged from the guide portion 92d, and the center shaft 106 can be inserted as shown in FIG. The center diameter of the gear plate 2 is accommodated in a recess 26 formed at the approximate center of the third step portion 25. One end of the coil spring 10 is locked in a hole 94 formed in the memory plate 9, and the other end is locked in a hole 26a provided in the bottom portion of the recess 26, as shown in FIG. In this state, the memory plate 9 is always urged counterclockwise by the coil spring 10.

  Next, the operation of the reclining device configured as described above will be described. Referring to FIG. 3, in a state where the operation lever 107 is not operated, the cam 6 and the lever plate 8 integrated therewith are urged to rotate clockwise by the spiral springs 7 and 7. Therefore, the pressing portions 5 a and 5 a of the lock gears 5 and 5 are pressed against the cam surfaces 6 a and 6 a of the cam 6, and the outer teeth 51 of the lock gear 5 are engaged with the inner teeth 21 of the gear plate 2. Therefore, relative rotation between the base plate 1 and the gear plate 2 is prevented through the lock gear 5 slidably fitted in the guide portion 50a of the base plate 1 in the radial direction.

  That is, in this state, the reclining device 105 is locked by a known lock mechanism including the lock gears 5 and 5, the cam 6, the spiral springs 7 and 7, the lever plate 8, and the like, and the inclination angle of the seat back 102 is fixed. Further, in the state shown in FIG. 3, the external teeth 51 of the lock gear 5 are in a position in contact with the arc portion 22 at the counterclockwise end of the gear plate 2, and the seat back 102 corresponds to the most upright position A shown in FIG. To do. In this state, the protrusion 52 of the lock gear 5 is loosely fitted in the cam hole 81 of the lever plate 8 and also in the wide portion 92a of the long hole 92 formed in the memory plate 9 as shown in FIG. The lock gear 5 is prevented from sliding in either the cam hole 81 or the long hole 92.

  Next, when the operation lever 107 is rotated (operated clockwise in FIG. 1) while the reclining device 105 is locked, the biasing force of the spiral springs 7 and 7 is changed from the state shown in FIG. The cam 6 and the lever plate 8 integrated therewith are rotated counterclockwise. Then, the pressing of the pressing portions 5a of the lock gears 5 and 5 by the cam surface 6a of the cam 6 is released, and at the same time, the protrusion 52 of the lock gear 5 is guided by the cam hole 81 of the lever plate 8 so that the lock gear 5 moves in the direction of the center shaft 106. The outer teeth 51 of the lock gear 5 are disengaged from the inner teeth 21 of the gear plate 2. As a result, the reclining device 105 is unlocked, and the inclination angle of the seat back 102 can be adjusted. In this state, if the seat back 102 is adjusted within the reclining adjustment range a in FIG. 1 and the operation of the operation lever 107 is released, the inclination angle of the seat back 102 is fixed at the adjusted position again.

  The above operation relates to a lock and adjustment function by a known lock mechanism. In this state, the protrusion of the lock gear 5 loosely fitted in the long hole 92 formed in the memory plate 9 through the cam hole 81 of the lever plate 8. 52 is set to always be located in the wide portion 92a. For this reason, the operation of the lock gears 5 and 5 is not restricted by the long hole 92 formed in the memory plate 9, and the memory mechanism including the memory plate 9 and the coil spring 10 does not participate in the above operation. .

  Next, the operation of the neutral position return mechanism, which is a feature of the present invention, will be described. The angle range b shown in FIG. 1 is a lock-free range in which the seat back 102 is not locked and the unlocked state is maintained even if the finger is released from the operation lever 107, and the lock shown in FIG. When the seat back 102 is tilted backward from the free range, the seat back 102 is first locked at a neutral position shown in FIG. C (a position tilted backward by a predetermined angle from the initial stage lock position).

  5 to 8 show the movement of the gear plate 2, the lock gear 5, the cam 6, and the memory plate 9 until the seat back 102 is rotated from the lock-free range b to the neutral position C and the reclining device is locked. For the sake of clarity, parts other than those described above are omitted. Further, in order to correspond to the rotation direction of the seat back 102 in FIG. 1, the left and right are shown reversely, and FIG. 3 corresponds to the view seen from the back side of the drawing.

  FIG. 5 shows a state in which the seat back 102 is in the forward position B of the seat back 102 at the foremost end of the lock-free range b. This is a state in which the operation lever 107 is pulled upward and the lock gears 5 and 5 are retracted in the radial center direction, and the seat back 102 is tilted forward, as in the normal tilt adjustment operation. When the seat back 102 is tilted forward with the lock gears 5, 5 not engaged with the internal teeth 21, the gear plate 2 attached to the seat back 102 rotates integrally, and each engagement of the third step portion 25. The memory plate 9 also rotates integrally with the gear plate 2 in a state where the one side 25aa of the stop portion 25a and the engaging edge 93a of the notch portion 93 of the memory plate 9 abut.

  When the memory plate 9 rotates in the forward tilt direction (counterclockwise direction in the drawing), the projections 52 and 52 of the lock gears 5 and 5 are pushed toward the center in the radial direction by the inclined portions 92c of the long holes 92 and 92, thereby narrowing the width. It will be located in the part 92b. When the projections 52 and 52 of the lock gears 5 and 5 are positioned in the narrow portion 92b, the finger is released from the operation lever, and the urging force of the spiral springs 7 and 7 rotates the cam 6 to cause the lock gears 5 and 5 to have a radius. Even when pressed outward in the direction, the movement of the protrusions 52 and 52 is restricted by the guide portion 92d of the narrow portion 92b, and the seat back 102 is not locked. Normally, passengers get on and off the rear seat in this state.

  Next, in order to allow an occupant to sit on the seat from the state of FIG. 5, the seat back 102 is tilted backward. 6 starts to return the seat back 102 from the state of FIG. 5 and rotates the seat back 102 backward by an angle difference α−β between the predetermined angle range α of the notch 93 and the predetermined angle range β of the locking portion 25a. Shows the state. During this time, the seat back 102 and the gear plate 2 only rotate. This is because the spiral springs 7 and 7 rotate the cam 6 to press the lock gears 5 and 5 outward in the radial direction, and the frictional force generated by the projections 52 and 52 pressing the narrow portion 92b is more memory. This is because the memory plate 9 is held at the position shown in FIG. 5 because it is greater than the biasing force of the coil spring 10 that biases the plate 9 to rotate backward. When the gear plate 2 rotates by an angle α−β between the predetermined angle range α of the notch 93 and the predetermined angle range β of the locking portion 25a, the locking portion 25a of the second step portion 25 of the gear plate 2 is rotated. The other side 25ab and the locking edge 93b of the notch 93 of the memory plate 9 abut.

  The seat back 102 is further removed from the state shown in FIG. 6 in which the other side 25ab of the locking portion 25a of the third step portion 25 of the gear plate 2 and the locking edge 93b of the notch portion 93 of the memory plate 9 contact each other. When returning, the memory plate 9 rotates integrally with the seat back 102 and the gear plate 2, and the projections 52 and 52 of the lock gears 5 and 5 slide on the guide portion 92 d of the long hole 92. The seat back 102 is more than the state in which the protrusion 52 of the lock gear 5 shown in FIG. 7 is in the inclined portion 92c provided at the end of the guide portion 92d where the narrow portion 92b of the long hole 92 of the memory plate 9 switches from the wide portion 92a. When rotating, the contact between the long hole 92 and the protrusion 52 is released, and the lock gear 5 is pushed radially outward by the rotation of the cam 6 by the spiral springs 7, 7, and the internal teeth 21 of the gear plate 2 and the lock gear 5 The outer teeth 51 are engaged and the seat back 102 is locked.

  As shown in FIG. 8, since the contact between the elongated hole 92 and the protrusion 52 is released, the friction force generated when the protrusions 52 and 52 press the guide portion 92d is eliminated. The urging force of the memory plate 9 causes the seat back to tilt backward (clockwise in the figure), and the side edge 25aa of the locking portion 25a of the third step portion 25 and the locking edge of the notch portion 93 of the memory plate 9 It rotates until 93a contacts. Thereby, the inclination angle of the seat back 102 shown in FIG. 8 is within a predetermined angle range of the notch 93 from the forward position B (state shown in FIG. 5) to the state shown in FIG. There is a difference in the rotation angle between the memory plate 9 and the gear plate 2 by an angle difference α−β between α and the predetermined angle range β of the locking portion 25a, and the protrusion 52 of the lock gear 5 is in the wide portion 92a of the long hole 92. The angle is tilted rearward by an angle α-β from the initial position where the reclining device can be locked.

  In the conventional reclining device, the lock gear 5 rides on the arc portion 22 where the inner teeth 21 are not formed on the inner periphery of the gear plate 2 to form a lock-free range. However, the lock gear 5 is formed by the long hole 92 of the memory plate 9. Since the protrusion 52 of the projection is pulled toward the center in the radial direction, a lock-free range can be formed. Therefore, the reclining device of the present invention does not necessarily require the arc portion 22, but the lock gear 5 and the gear plate 2 near the most upright position A. It is preferable to provide this arc portion 22 in order to ensure the engagement of the two.

  As described above, since the lock-free range b when the circular arc portion 22 is not provided is formed by the long hole 92, the inclined portion 92c of the long hole 92 is positioned immediately next to the protrusion 52 at the most upright position A. Will do. The inclined portion 92c has an error in the position in the rotational direction due to the processing accuracy of the memory plate 9 and the stacking accuracy of the locking portions 25a of the gear plate 2 and the notch portion 93 of the memory plate 9, and so on. As described above, in the vicinity of the most upright position A, the protrusion 52 rides on the inclined portion 92c, and the lock may be incomplete.

  Therefore, the arc plate 22 is provided in the gear plate 2 as in the prior art, and when the seat back 102 tilts forward, the projection 52 comes into contact with the inclined portion 92c after the lock gear 5 rides on the arc portion 22. By disposing the guide portion 92d in a direction (clockwise in FIG. 9) for delaying the protrusion 52, the engagement between the lock gear 5 and the gear plate 2 near the most upright position A can be ensured. Incidentally, the amount by which the inclined portion 92c is shifted in the rotational direction can be adjusted by adjusting the neutral position to return by the difference in angle between the locking portion 25a of the gear plate 2 and the notch portion 93 of the memory plate 9.

  10 to 12 show embodiments according to the inventions of claims 3 to 6 and correspond to FIGS. 2, 4, and 9, respectively. The above-described embodiment is different from the memory plate 9 and the coil spring 10, and these differences will be described below.

  First, as shown in FIGS. 10 and 11, the memory plate 201 has a substantially ring shape with the center shaft 106 as the center. Like the memory plate 9, the memory plate 201 has two pieces at an appropriate interval on the outer periphery. A notch 201a is provided. A substantially arc-shaped guide portion 201b that restricts the lock gear 5 from moving radially outward by the contact of the protrusion 52 of the lock gear 5 and the spiral spring 202 are engaged with the substantially ring-shaped inner peripheral edge. A hook piece 201d is formed.

  When the projection 52 of the lock gear 5 is in the range where the guide portion 201b is formed, the lock gear 5 is prevented from moving in the radial direction of the gear plate 2 regardless of the position of the cam hole 81 of the lever plate 8. The outer teeth 52 of the lock gear 5 do not mesh with the inner teeth 21 of the gear plate 2. Further, when the protrusion 52 of the lock gear 5 is positioned on the inner peripheral edge 201c that is not the guide part 201b, the lock gear 5 is prevented from coming into contact with the substantially arcuate peripheral edge. The gear plate 2 is moved in the radial direction without any trouble.

  Next, the spiral spring 202 has a shape in which a terminal on the outer side of the spiral is bent back in the direction opposite to the winding direction, and a terminal on the center side is bent in the same direction as the winding, and the outer terminal is the memory plate. The terminal on the center side is locked to a substantially columnar protrusion 28 projecting from the bottom portion of the gear plate 2. A plurality of the protrusions 28 are provided so that the position of the spiral spring 202 is not shifted apart from that for locking the spiral spring 202, and can be elastically deformed efficiently.

  The operation of the memory plate 201 and the spiral spring 202 described above is the same as that of the memory plate 9 and the coil spring 10 and will not be described. However, compared with the combination of the memory plate 9 and the coil spring 10, the thickness of the memory plate 201 is the same. Since a spring member for biasing the memory plate can be installed in the space, the thickness of the reclining device in the axial direction can be reduced.

  FIG. 12 is a plan view illustrating an embodiment of the invention according to claim 6 and corresponding to FIG. The peripheral edge that reaches the end of the guide part 201b shown in FIG. 12 protrudes in the center direction from the arc of the guide part centered on the center shaft. By doing so, the memory plate 201 is prevented from being rotated by the gear plate 2 within a certain range in which the memory plate 201 can rotate with respect to the gear plate 2.

  This is because if the memory plate rotates due to friction between the peripheral edge of the memory plate 201 and the gear plate 2 and the notch portion 201a of the memory plate 201 and the engaging portion 25a of the gear plate 2 do not come into contact with each other, the lock gear 5 Since the position at which the outer teeth 51 of the gear plate 2 mesh with the inner teeth 21 of the gear plate 2 deviates from the neutral position, the protrusion of the lock gear 5 is provided with the guide 52 by providing resistance to the rotation of the memory plate 201 by extending the guide. Before being disengaged from 201b, the notch 201a of the memory plate and the locking portion 25a of the gear plate are brought into contact with each other.

  Further, the peripheral edge 52a where the projection 52 of the lock gear 5 contacts the guide part 201b is inclined so as to follow the protruding shape of the guide part 201b as shown by the two-dot chain line in FIG. The guide plate 201b and the peripheral edge 52a of the projection 52 are brought into surface contact until the projection 52 is released from the portion 201b, so that the memory plate 201 is geared within a certain range in which the memory plate 201 can rotate with respect to the gear plate 2. It can prevent more reliably that it rotates with the plate 2.

It is a side view showing a seat provided with a reclining device concerning the present invention. It is sectional drawing of the XX part of FIG. It is sectional drawing in the Y1-Y1 part of FIG. It is sectional drawing in the Y2-Y2 part of FIG. It is a figure which shows the relationship of each member when a seat back exists in the forward position B. It is a figure which shows the state in the middle of the seat back being inclined backward from the state of FIG. FIG. 7 is a diagram showing the relationship among members immediately before the seat back is further tilted backward from the state of FIG. 6 and returned to the neutral position. It is a figure which shows the state by which the seat back 102 was returned and fixed to the neutral position. It is a top view which shows the vicinity of the most upright position when the protrusion 52 rides on the inclined part 92c. FIG. 3 is a sectional view corresponding to FIG. 2, showing an embodiment of the third and fourth aspects of the invention. It is sectional drawing corresponding to FIG. 4 which shows the embodiment of invention of Claim 3, 4. FIG. It is a top view explaining the embodiment of the invention concerning Claim 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base plate 2 Gear plate 21 Internal tooth 22 Arc part 5 Lock gear 51 External tooth 52 Projection 6 Cam 7 Spiral spring 8 Lever plate 9 Memory plate 92 Long hole 92a Wide part 92b Narrow part 92c Inclined part 92d Guide part 10 Coil spring

Claims (6)

A substantially disc-shaped base plate fixed to either the seat cushion side or the seat back side of the seat;
A substantially disc-shaped gear plate having internal teeth assembled so as to face the base plate in a rotatable manner;
A plurality of lock gears having outer teeth which are guided and assembled to the base plate so as to be movable only in the radial direction and which can mesh with the inner teeth of the gear plate;
A cam for controlling the movement of the lock gear radially outward to mesh the lock gear with the inner teeth of the gear plate;
A spring that rotationally biases the cam in a direction in which the lock gear meshes with the internal teeth;
A lever plate that rotates integrally with the cam and engages with a protrusion projecting from the lock gear to control movement of the lock gear inward in the radial direction;
A center shaft that is inserted through substantially the center of the base plate and the gear plate and can rotate integrally with the cam;
An operation member connected to the center shaft and capable of rotationally driving the center shaft against the biasing force of the spring.
A locking portion provided on the gear plate;
A substantially disc shape centering on the center shaft, and having at least one notch portion engaged with the engaging portion on the outer peripheral edge, and the gear plate within a certain range in which the engaging portion is movable within the notch portion. A substantially arcuate guide part centered on the center shaft that restricts the lock gear from moving radially outward by the abutment of the lock gear protrusion inside the disk and a part of the periphery A memory board in which a long hole is drilled,
A spring member for rotationally biasing the memory plate,
When the seat back is in the most upright position from the forward position, the lock gear protrusion that rotates relative to the memory plate is in the angular range of the guide portion to form a lock-free range,
When the seat back is in the last tilted position from the most upright position, the lock gear protrusion is in the range where it does not contact the memory plate inside the elongated hole, forming an adjustment range,
The spring member rotationally biases the memory plate in a direction in which the protrusion of the lock gear is disengaged from the guide portion;
The memory plate resists the urging force of the spring member when it can rotate within the predetermined range with respect to the gear plate when the seat back is tilted backward with the projection of the lock gear in contact with the guide portion. And a reclining device that can rotate integrally with the base plate.   The gear plate is formed in a substantially bowl shape having a stepped step portion, the first step portion in which the inner teeth are formed on the inner periphery of the opening, and the radius of the circumference is smaller than that of the first step portion. A second step portion that is in sliding contact with the outer peripheral edge of the memory plate, and a third step portion that is smaller in circumference than the second step portion and in contact with the outer peripheral edge of the memory plate. The reclining device according to claim 1, wherein the reclining device is disposed between the gear plate and the gear plate. A substantially disc-shaped base plate fixed to either the seat cushion side or the seat back side of the seat;
A substantially disc-shaped gear plate having internal teeth assembled so as to face the base plate in a rotatable manner;
A plurality of lock gears having outer teeth which are guided and assembled to the base plate so as to be movable only in the radial direction and which can mesh with the inner teeth of the gear plate;
A cam for controlling the movement of the lock gear radially outward to mesh the lock gear with the inner teeth of the gear plate;
A spring that rotationally biases the cam in a direction in which the lock gear meshes with the internal teeth;
A lever plate that rotates integrally with the cam and engages with a protrusion projecting from the lock gear to control movement of the lock gear inward in the radial direction;
A center shaft that is inserted through substantially the center of the base plate and the gear plate and can rotate integrally with the cam;
An operation member connected to the center shaft and capable of rotationally driving the center shaft against the biasing force of the spring.
A locking portion provided on the gear plate;
A ring-shaped ring centered on the center shaft, having at least one notch portion that engages with the engaging portion on the outer periphery, and the gear plate within a certain range in which the engaging portion is movable within the notch portion. A memory plate having a substantially arcuate guide portion centering on a center shaft that restricts the lock gear from moving radially outward by the contact of the protrusion of the lock gear on the inner peripheral edge;
A spring member for rotationally biasing the memory plate,
When the seat back is in the most upright position from the forward position, the lock gear protrusion that rotates relative to the memory plate is in the angular range of the guide portion to form a lock-free range,
When the seat back is in the last tilted position from the most upright position, the lock gear protrusion is in a range where it does not contact the memory plate, forming an adjustment range,
The spring member rotationally biases the memory plate in a direction in which the protrusion of the lock gear is disengaged from the guide portion;
The memory plate resists the urging force of the spring member when it can rotate within the predetermined range with respect to the gear plate when the seat back is tilted backward with the projection of the lock gear in contact with the guide portion. And a reclining device that can rotate integrally with the base plate. The gear plate is formed in a substantially bowl shape having a stepped step portion, the first step portion in which the inner teeth are formed on the inner periphery of the opening, and the radius of the circumference is smaller than that of the first step portion. A second step portion that is in sliding contact with the outer periphery of the memory plate, and a third step portion that is smaller in circumference than the second step portion and in contact with the outer periphery of the memory plate;
The spring member is a spiral spring having a shape in which a terminal on the outer side of the spiral is bent back in the direction opposite to the winding direction, and a terminal on the center side is bent in the same direction as the winding, and the outer terminal is an inner peripheral edge of the memory plate. Is locked to a hook-shaped hook projecting on the center, and a terminal on the center side is locked to a substantially cylindrical protrusion projecting on the bottom portion of the gear plate;
The reclining device according to claim 3, wherein the spiral spring is disposed in the third step portion. The gear plate is provided with an arc portion in which no internal teeth are formed, and the arc portion is formed with a mountain height higher than the internal teeth;
An end portion of the guide portion provided on the memory plate is provided with an inclined portion inclined outward in the radial direction;
When the seat back is moved forward within the lock-free range, the lock gear protrusion is moved in the radial center direction by the inclined portion after the outer teeth of the lock gear ride on the arc portion, and are guided and contacted by the guide portion. The reclining device according to claim 1, wherein   The reclining device according to claim 1, wherein a peripheral edge leading to an end of the guide portion projects in a center direction from an arc of the guide portion centered on a center shaft.

Images