JP4606791B2 - Auxiliary seat back locking mechanism - Google Patents

Description

  The present invention relates to a lock mechanism for an auxiliary seat back that improves operability of unlocking.

  Conventionally, there is an auxiliary seat back that can be tilted to the standing position in the seat back state and the forwardly moved position in the armrest state on the side of the seat back of the seat, and can be tilted to the side standing position in the walk-through state together with the auxiliary seat cushion. (See Patent Document 1).

The auxiliary seat back is locked to the seat back by the auxiliary seat back locking mechanism so as not to tilt forward at the standing position, and coupled with the auxiliary seat cushion being coupled at the standing position. So that it does not tilt in the sideways direction.
JP 2003-127727 A

  However, when the structure in which the auxiliary seat back and the auxiliary seat cushion are tilted in an independent state is adopted, the auxiliary seat back requires a first locking mechanism for locking so as not to tilt forward in the standing position, and the side stand A second locking mechanism that locks so as not to tilt in the direction is also required.

  For this reason, the first lock mechanism is unlocked when the auxiliary seatback is tilted forward from the standing position, and then the second lock mechanism is unlocked when tilted in the side-standing direction from the forward tilt position. Therefore, there is a problem that the operability is poor because two unlock operations are required.

  The present invention has been made to solve the above problems, and provides an auxiliary seat back locking mechanism that improves operability by allowing two locking mechanisms to be unlocked by a single unlocking operation. It is an object to do.

In order to solve the above-mentioned problem, the invention of claim 1 tilts between the standing position in the seat back state, the forward position in the armrest state, and the side standing position in the walk-through state on the side of the seat back of the seat. A possible auxiliary seat back,
A first shaft member fixed to the side portion of the seat back, a second shaft member supported by the first shaft member so as to be able to turn back and forth, and an auxiliary seat supported by the second shaft member so as to be turned left and right. The auxiliary seat back is tilted back and forth between the standing position and the forward tilt position by the first shaft member, and the auxiliary seat back is movable between the forward tilt position and the side standing position by the second shaft member. And a second shaft member locking mechanism that locks the second shaft member to the first shaft member at an upright position of the auxiliary seat back, and an auxiliary seat that locks the auxiliary seat back to the second shaft member A back lock mechanism is provided, and a linkage mechanism that unlocks the other lock mechanism in association with the unlocking operation of one of the lock mechanisms is provided.

The invention according to claim 2 is the lock mechanism of the auxiliary seat back according to claim 1, wherein the second shaft member lock mechanism is provided on the second shaft member and can swing between the lock position and the unlock position. And a lock plate which is fixed to the side portion of the seat back and has a lock recess formed on the outer peripheral edge to engage the lock lever at the standing position of the auxiliary seat back.
The auxiliary seat back lock mechanism is provided on the second shaft member and can be moved into and out of the lock position and the unlock position. The auxiliary seat back lock mechanism is provided on the auxiliary seat back and the lock pin is engaged at the standing position of the auxiliary seat back. It consists of a lock hole that fits together,
The lock lever and the lock pin are linked by a linkage mechanism that simultaneously locks or unlocks, and when the lock lever is unlocked and the auxiliary seat back is tilted forward, the lock lever is moved to the outer periphery of the lock plate. And the unlocked state is maintained together with the lock pin.

The invention of claim 3 is an auxiliary seat back that can be tilted to an upright position, a forward-turned position, and a side-standing position on the side of the seat back of the seat,
A first shaft member fixed to the side portion of the seat back, a second shaft member supported by the first shaft member so as to be able to turn back and forth, and an auxiliary seat supported by the second shaft member so as to be turned left and right. The auxiliary seat back is a first shaft member, and can be tilted back and forth between the standing position in the seat back state and the forward position in the armrest state. A first auxiliary seat back locking mechanism that can tilt left and right between the position and the side standing position in the walk-through state and locks the auxiliary seat back to the seat back at the standing position of the auxiliary seat back; and a second shaft member auxiliary seat back and the second auxiliary seat back locking mechanism is provided to lock the, and the first auxiliary seat back locking mechanism to unlock operation auxiliary seat back in conjunction to tilted forward, the second auxiliary Interlocking mechanism for unlocking the over-back locking mechanism is characterized in that is provided.

According to a fourth aspect of the present invention, there is provided the auxiliary seat back locking mechanism according to the third aspect, wherein the second auxiliary seat back locking mechanism is provided on the second shaft member and moves into and out of the locked position and the unlocked position. A lock pin that is provided in the auxiliary seat back and engages with the lock pin in the standing position of the auxiliary seat back, a lock lever that can swing between the lock position and the unlock position, and the seat back It is composed of a lock plate fixed to the side part and formed so that the outer peripheral edge gradually expands in the forward tilt direction of the auxiliary seat back,
The lock lever and the lock pin are linked by a linkage that simultaneously locks or unlocks, and when the auxiliary seat back is tilted forward , the lock lever is unlocked and the lock lever expands the diameter of the lock plate. The unlocked state is maintained together with the lock pin by riding on the outer peripheral edge.

  According to a fifth aspect of the present invention, there is provided the auxiliary seat back locking mechanism according to the second or fourth aspect, wherein a position restricting groove having an angular range between an upright position and a forward tilt position of the auxiliary seat back is formed on the outer peripheral edge of the lock plate. And the second shaft member is provided with a stopper pin that enters the position restricting groove and stops the rotation of the auxiliary seat back.

  A sixth aspect of the invention is the auxiliary seat back locking mechanism according to any one of the second, fourth, and fifth aspects, wherein the auxiliary seat back is provided with a front-rear position and a side-standing position of the auxiliary seat back. And a stopper pin which is provided in the second shaft member to stop the rotation of the auxiliary seat back by being provided in the position restricting hole. .

  The invention according to claim 7 is the lock mechanism for the auxiliary seat back according to claim 6, wherein the stopper pin can get over the position restricting hole at the front-rear position and the side-standing position of the auxiliary seat back. The protrusion part for use is formed, It is characterized by the above-mentioned.

  The invention according to claim 8 is the auxiliary seat back locking mechanism according to any one of claims 2, 4 to 7, wherein the lock lever and the lock pin are locked to either the lock lever or the lock pin. A common spring for urging the position is provided.

  According to the invention of claim 1, the auxiliary seat back and the auxiliary seat cushion are tilted in an independent state, and the second shaft member locking mechanism locks the auxiliary seat back so as not to tilt forward in the standing position; An auxiliary seat back lock mechanism that locks so as not to tilt in the side-standing direction. When either the second shaft member lock mechanism is unlocked, for example, the auxiliary seat back lock mechanism is unlocked via the linkage mechanism. Since the two locking mechanisms can be unlocked simultaneously by one unlocking operation (one action), the operability is improved.

  According to the invention of claim 2, since the second shaft member locking mechanism can be constituted by a lock lever and a lock plate, and the auxiliary seat back locking mechanism can be constituted by a lock pin and a lock hole, the structure is very simple and operates. The reliability is high and the manufacturing cost is low.

According to the invention of claim 3, the first auxiliary seat back locking mechanism is configured to tilt the auxiliary seat back and the auxiliary seat cushion in an independent state, and locks the auxiliary seat back so as not to tilt forward at the standing position. And a second auxiliary seat back lock mechanism for locking so as not to tilt in the side standing direction, in conjunction with the tilting of the auxiliary seat back after the first auxiliary seat back lock mechanism is unlocked. Since the second auxiliary seat back lock mechanism is unlocked, the two lock mechanisms can be unlocked by one unlock operation (one action), so that the operability is improved. .

  According to the invention of claim 4, since the second auxiliary seat back lock mechanism can be constituted by the lock pin, the lock hole, the lock lever, and the lock plate, the structure is extremely simple, the operation reliability is high, and the manufacturing cost is low. become. The first auxiliary seat back lock mechanism may employ a known inexpensive catch mechanism such as a striker and a fork.

  According to the fifth aspect of the present invention, the position of the auxiliary seat back can be regulated between the upright position and the forward tilt position only by forming the position regulating groove in the lock plate and providing the stopper pin on the second shaft member.

  According to the invention of claim 6, the position of the auxiliary seat back can be regulated between the forwardly-turned position and the side-standing position only by forming the position-regulating hole in the auxiliary seat-back and providing the stopper pin on the second shaft member. Become.

  According to the seventh aspect of the present invention, since the moderation protrusion that the stopper pin can get over is formed at the forward and backward positions of the auxiliary seat back, the auxiliary seat back is moved to the forward and backward positions. This makes it possible to prevent the auxiliary seat back from inadvertently falling from the side position to the forward position.

  According to the eighth aspect of the present invention, the lock lever and the lock pin are linked by the linkage portion, and each can be urged to the lock position only by providing one common spring.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  The vehicle seat 1 shown in FIG. 1A is a two-part split type, and an auxiliary seat 2 is provided between the left seat 1 (L) and the right seat 1 (R). 2 is composed of an auxiliary seat back 2A and an auxiliary seat cushion 2B. The auxiliary seat back 2A is supported by the seat back 1A of the left seat 1 (L), and the auxiliary seat cushion 2B is supported by the left seat 1. (L) is supported by the seat cushion 1B.

  Then, the auxiliary seat back 2A tilts forward from the standing position in the seat back state as shown in FIG. 1A to the forward position in the armrest state as shown in FIG. 1B at the side position of the seat back 1A. (See arrow a). Although not specifically shown, the auxiliary seat back 2A is moved from the forward position as shown in FIG. 1 (c) in a state where the auxiliary seat cushion 2B is housed in the seat cushion 1B of the left seat 1 (L). It can be tilted to the side standing position in the walk-through state (see arrow b).

  FIG. 2 (a) is an assembled perspective view of the back frame 3 of the left seat 1 (L) and the auxiliary back frame 4 of the auxiliary seat back 2A, and FIG. 2 (b) shows the lock mechanism 5 of the auxiliary seat back 2A. FIG. 3 is an exploded perspective view of the lock mechanism 5.

  Side frames 3L and 3R are respectively fixed to the side portions of the back frame 3. The side frames 3R on the auxiliary back frame 4 side are provided with support bosses 10 having serration holes as shown in FIG. Position fixing pins 11 are provided on both sides of the support boss 10.

  The first shaft member 12 of the lock mechanism 5 is formed with a serration shaft portion 12a that is non-rotatably fitted in the serration hole of the support boss 10, and the serration shaft portion 12a is formed in the serration hole of the support boss 10. When it is fitted to, it is locked with a snap ring or the like so as not to come off. That is, the first shaft member 12 is fixed in a state of protruding from the side portion of the seat back 1A.

  The second shaft member 13 of the lock mechanism 5 includes a second shaft 14, a laterally U-shaped bracket 15 fixed to the lower portion of the second shaft 14, and a case body 16 fixed to the lower portion of the bracket 15. It consists of and. This case body 16 is a combination of half case bodies 16a and 16b.

  When the center hole 16c of the case body 16 of the second shaft member 13 is fitted to the first shaft member 12, the second shaft member 13 can be rotated back and forth by the first shaft member 12 (see arrow a). Become supported.

  An outer pipe 17 is fixed to the auxiliary back frame 4, and a rectangular plate 18 is attached across the outer pipe 17 and the auxiliary back frame 4.

  By fitting the outer pipe 17 of the auxiliary back frame 4 to the second shaft (inner pipe) 14 of the second shaft member 13, the auxiliary back frame 4 can be rotated left and right by the second shaft member 13 (arrow b). See).

  As a result, the auxiliary seat back 2A is supported by the first shaft member 12 so as to be tiltable back and forth between the standing position and the forward tilt position, and at the second shaft member 13, the forward tilt position and the side standing position are It will be supported so that it can tilt to the left and right.

  The second shaft member locking mechanism 20 that locks the second shaft member 13 to the first shaft member 12 at the standing position of the auxiliary seat back 4 is pinned to the half case body 16 a of the case body 16 of the second shaft member 13. 21, and is constituted by an inverted L-shaped lock lever 22 that can swing between a lock position in the left-handed direction and an unlock position in the right-handed direction, and a cam-shaped lock plate 23.

  The lock plate 23 is formed with a center caulking hole 23a that is caulked and fixed to the large-diameter portion 12b of the first shaft member 12, and is fitted to the position fixing pin 11 provided in the side frame 3R. The fixing hole 23b is formed, and the position fixing hole 23b is fitted to the position fixing pin 11, so that the lock plate 23 is fixed to the back frame 3R so as not to rotate.

  As shown in FIG. 6A, the lock plate 23 is engaged with the lower end portion 22b of the lock lever 22 that is swung counterclockwise (see arrow c) at the lock position at the standing position of the auxiliary seat back 2A. 23c is formed on the outer peripheral edge. When the lock lever 22 is engaged with the lock recess 23c of the lock plate 23, the second shaft member 13 of the auxiliary seat back 2A is locked so as not to tilt forward (see arrow a) from the standing position in the forward direction. It becomes like this.

  Then, the lock lever 22 is swung clockwise (see arrow d) to the unlock position by the manual operation tab 22a to unlock from the lock recess 23c, and then the second shaft member 13 of the auxiliary seat back 2A is moved from the standing position. When tilted forward in the forward direction, the lock lever 22 rides on the outer peripheral edge of the lock plate 23 and the unlocked state is maintained as shown in FIG. 6B.

  On the outer peripheral edge of the lock plate 23, an arc-shaped position restricting groove 23d is formed in the angular range between the standing position and the forward-falling position of the auxiliary seat back 2A, and the case body 16 of the second shaft member 13 is formed. A stopper pin 24 that is inserted into the position restricting groove 23d is fixed to the half case body 16a.

  Then, as shown in FIG. 6 (a), when the auxiliary seat back 2A is in the standing position, the stopper pin 24 is stopped against the lower end 23e of the position restricting groove 23d, so that the rear movement of the auxiliary seat back 2A exceeds the standing position. The stopper pin 24 is stopped against the upper end 23f of the position restricting groove 23d at the forward position of the auxiliary seat back 2A, so that the forward movement of the auxiliary seat back 2A beyond the forward position is stopped. become.

  The auxiliary seat back locking mechanism 26 that locks the auxiliary seat back 2A to the second shaft member 13 at the standing position of the auxiliary seat back 4 is guided by the sleeve 27 of the bracket 15 of the second shaft member 13, and A lock pin 28 that can be moved into and out of the unlock position, and a lock hole 29a that is provided in the lower plate 29 of the outer pipe 17 of the auxiliary seat back 2A and engages with the lock pin 28 at the standing position of the auxiliary seat back 2A. It consists of

  Then, as shown in FIG. 6A, the lock pin 28 protrudes (see arrow f) at the standing position of the auxiliary seat back 2A and engages with the lock hole 29a of the lower plate 29, whereby the auxiliary seat back 2A. Is locked so as not to tilt in the side standing direction from the standing position, and as shown in FIG. 6 (b), the lock pin 28 is immersed (see arrow g), and is removed from the lock hole 29a of the lower plate 29. The auxiliary seat back 2A is unlocked so that it can tilt in the side-standing direction.

  The lock lever 22 and the lock pin 28 are linked by a linkage mechanism 31 that simultaneously locks or unlocks.

  That is, as shown in FIG. 3 and FIG. 4B, a long hole 22d is formed in the side end 22c of the lock lever 22, and a spring hook plate 32 is disposed on the back surface of the side end 22c. A screw shaft 33 fitted into the elongated hole 22d from the surface of the side end portion 22c passes through the hole 32b of the spring hook plate 32 and is screwed to the lower end portion of the lock pin 28.

  When the lock lever 22 is swung clockwise to the unlock position, the lock pin 28 is moved into and out of the unlock position via the screw shaft 33, and the lock lever 22 is swung counterclockwise to the lock position. Then, the lock pin 28 is projected and moved to the lock position via the screw shaft 33.

Between the bracket 15 of the spring hook plate 32 and the second shaft member 13, together with the biasing of the lock pin 28 in the projecting direction (lock position), the lock lever 22 in the left-handed swing direction (lock position) A common spring 34 for biasing is latched.

  The spring hook plate 32 can swing independently of the side end portion 22c of the lock lever 22 around the screw shaft 33, and the left and right claw portions 32a abut against the lower end portion of the lock pin 28. As a result, the swing range is regulated. 6A and 6B as compared with the case where the spring 34 is directly hooked on the side end portion 22c of the lock lever 22 by hooking the lower end portion of the spring 34 on the spring hook plate 32. The spring 34 can always be maintained in the vertical state regardless of the swinging position of the side end 22c of the lock lever 22.

  On the other hand, as shown in FIG. 3, the first shaft member 12 fitted in the center hole 16c of the case body 16 of the second shaft member 13 has a friction leaf spring at the protruding end from the half case body 16b. 36a and a washer 36b are fitted, and a washer 36c is fixed by caulking to the protruding end.

  By this leaf spring 36a, friction is imparted to the forward / backward tilt between the standing position and the forward tilt position of the auxiliary seat back 2A.

  As shown in detail in FIG. 4, the tip of the second shaft 14 of the second shaft member 13 is provided with a shaft 38 having an upper portion with a male screw portion 38a and a lower portion with a caulking shaft portion 38b. A cover plate 39a, a washer 39b, a friction spring washer 39c, and a washer 39d are fitted into the caulking shaft portion 38b in order from the top, and the lower end portion of the caulking shaft portion 38b is expanded by caulking to prevent it from coming off. Then, together with the cover plate 39a and the like, the caulking shaft portion 38b of the shaft 38 is fitted inside from the tip end portion of the second shaft 14 which is an inner pipe, and the cover plate 39a is fixed to the tip end portion of the second shaft 14 by welding h. To do.

  A resin ring 40 is fitted into the tip of the outer pipe 17 and the second shaft 14 of the second shaft member 13 is fitted into the outer pipe 17. Referring to FIG. A cover body 41 that is prevented from rotating by a claw 41a that engages with the notch 17a at the front end is covered, and a nut 42 is screwed into a male thread portion 38a of the shaft 38 that protrudes from the center hole 41b of the cover body 41. The outer pipe 17 is fixed so as not to come off from the biaxial shaft 14.

  By the spring washer 39c, friction is imparted to the left-right tilting between the front-rear position and the side-standing position of the auxiliary seat back 2A.

  The distal end portion of the second shaft 14 is fitted and supported by the outer pipe 17 via the resin ring 40, and the lower end portion of the second shaft 14 is a resin of a resin receiver 45 (see FIG. 3) described later. The outer pipe 17 is fitted through the ring portion 45a. That is, the inner periphery of the outer pipe 17 and the outer periphery of the second shaft 14 are fitted via the resin ring 40 and the resin ring portion 45a so as not to directly contact each other.

  The lower plate 29 of the outer pipe 17 is formed with an arc-shaped position restricting hole 29b in the angular range between the forward position of the auxiliary seat back 2A and the side standing position, and the lower plate 29 is opposed to the lower plate 29. A stopper pin 44 that is inserted into the position restricting hole 29b is fixed to the upper surface of the bracket 15.

  A resin receiver 45 is applied to the lower surface of the lower plate 29 of the outer pipe 17. The resin receiver 45 is formed with a resin ring 45 a that is fitted into the lower end portion of the outer pipe 17, and the position described above. An arcuate position restricting hole 45b that is fitted into the restricting hole 29b is formed. The stopper pin 44 enters the position restricting hole 45b.

  Then, as shown in FIG. 5A, the side seating direction of the auxiliary seat back 2 </ b> A is determined by the upper end portion 45 c of the position restricting hole 45 b being held against the stopper pin 44 at the forward position of the auxiliary seat back 2 </ b> A. The rotation in the opposite direction is stopped, and the lower end portion 45d of the position restricting hole 45b is stopped against the stopper pin 44 at the side standing position of the auxiliary seat back 2A. Stops moving.

  In the position restricting hole 45b of the resin receiver 45, there are formed moderation protrusions 45e on which the stopper pin 44 can get over at the forward and backward positions of the auxiliary seat back 2A.

  With the configuration of the locking mechanism 5 of the first embodiment, when the auxiliary seat back 2A is in the standing position of FIG. 1 (a), as shown in FIG. 7 (a) and FIG. 8 (a), Since the lock lever 22 of the biaxial member locking mechanism 20 is engaged with the lock recess 23c of the lock plate 23, the auxiliary seat back 2A is locked so as not to tilt forward from the standing position in the forward direction.

  Further, since the lock pin 28 of the auxiliary seat back lock mechanism 26 is engaged with the lock hole 29a of the lower plate 29, the auxiliary seat back 2A is locked so as not to tilt in the side standing direction from the standing position.

  Then, the manual operation tab 22a of the lock lever 22 is pulled forward, and the lock lever 22 is pivoted to the unlock position (see arrow d) against the biasing force of the spring 34 to unlock from the lock recess 23c. At the same time, the lock pin 28 is moved into and out of the unlock position via the screw shaft 33 and comes out of the lock hole 29a of the lower plate 29.

  If the auxiliary seat back 2A is tilted slightly forward in the forward direction from the standing position in this state, the lock lever 22 rides on the outer peripheral edge of the lock plate 23, and both the lock lever 22 and the lock pin 28 are unlocked. The locked state is maintained.

  As described above, when the lock lever 22 of the second shaft member lock mechanism 20 is unlocked, the lock pin 28 of the auxiliary seat back lock mechanism 26 is unlocked in conjunction with this operation. Since the two locking mechanisms 20 and 26 can be unlocked simultaneously by the unlocking operation of the action), the operability is improved.

  Then, the auxiliary seat back 2A is moved forward to the forward position shown in FIG. 1 (b) (see FIGS. 7 (b) and 8 (b)), and then the auxiliary seat back 2A is stood side by side in FIG. 1 (c). It can be made to stand on the position [see FIG. 7 (c), FIG. 8 (c)].

  The auxiliary seat back 2A in the side standing position can be raised from the forward position to the standing position in the reverse procedure to the above. In the standing position, the second shaft member locking mechanism 20, the auxiliary seat back locking mechanism 26, It is locked so as not to tilt in the forward and sideward directions.

  In the above configuration, the second shaft member locking mechanism 20 can be configured by the lock lever 22 and the lock plate 23, and the auxiliary seat back locking mechanism 26 can be configured by the lock pin 28 and the lock hole 29a, so that the structure is extremely simple. The operation reliability is high and the manufacturing cost is low.

  Further, the auxiliary seat back 2A can be regulated between the standing position and the forward position only by forming the position regulating groove 23d in the lock plate 23 and providing the stopper pin 24 in the case body 16 of the second shaft member 13. Become.

  Further, the auxiliary seat back 2A can be obtained by forming the position restricting hole 45b in the resin receiver 45 applied to the lower plate 29 of the outer pipe 17 of the auxiliary seat back 2A, and providing the stopper pin 44 on the bracket 15 of the second shaft member 12. The position of the back 2A can be regulated to the forward position and the side position.

  Furthermore, since the moderation projection 45e is formed in the position restricting hole 45b so that the stopper pin 44 can get over at the forward and backward positions of the auxiliary seat back 2A, the auxiliary seat back 2A is moved to the forward position and the side. While operating in the standing position, there is a sense of moderation, and the auxiliary seat back can prevent the 2A from inadvertently falling from the side standing position to the forward position.

  Further, by linking the lock lever 22 and the lock pin 23 with the linkage portion such as the screw shaft 33, it is possible to bias each of them to the lock position only by providing one common spring 34.

  The locking mechanism 5 of the first embodiment includes a second shaft member locking mechanism 20 that locks the auxiliary seat back 2A so as not to tilt forward at the standing position, and an auxiliary seat back locking mechanism that locks the tilting so as not to tilt in the side standing direction. However, as in the second embodiment shown in FIG. 9, the first auxiliary seat back lock mechanism 51 that locks the auxiliary seat back 2A so as not to tilt forward in the upright position, as in the second embodiment shown in FIG. And a second auxiliary seat back lock mechanism 52 for locking so as not to tilt in the side-standing direction.

  That is, the first auxiliary seat back locking mechanism 51 locks the auxiliary seat back 2A to the seat back 1A at the standing position of the auxiliary seat back 2A. As shown in FIG. The striker 53 is attached to the side of the back frame 3, and the catch mechanism 54 is attached to the outer pipe 17 of the auxiliary seat back 2A, and the catch mechanism 54 is locked to the striker 53, whereby the auxiliary seat back 2A is attached to the seat back 1A. Will be able to lock. The catch mechanism 54 includes a fork that locks the striker 53, a lock lever that locks the fork at the lock position, and the like, and is a well-known configuration that is widely used for door locks. A detailed description of the structure is omitted.

  When the strike mechanism 53 is unlocked by manually operating the catch mechanism 54, the auxiliary seat back 2A can be moved forward.

  The second auxiliary seat back lock mechanism 52 is basically a combination of the second shaft member lock mechanism 20 and the auxiliary seat back lock mechanism 26 of the first embodiment, and includes a lock pin 28 and a lock. Although the hole 29a, the lock lever 22, and the lock plate 23 'are configured, the lock plate 23' is not formed with the lock recess 23c, and the outer peripheral edge of the lock seat 23c is located at the position of the lock recess 23c. The difference is that the diameter is gradually increased in the forward tilt direction.

  In the configuration of the lock mechanism 50 of the second embodiment, when the auxiliary seat back 2A is in the standing position of FIG. 1A, the catch mechanism 54 pulls the striker 53 as shown in FIG. Since it is locked, the auxiliary seat back 2A is locked so that it does not tilt forward from the standing position in the forward direction.

  When the striker 53 is unlocked by the catch mechanism 54, the auxiliary seat back 2A can be moved forward. At this time, the auxiliary seat back 2A is moved forward as shown in FIGS. 9B to 9C. As described above, the lock lever 22 is swung clockwise (see the arrow d) to the unlock position while riding on the outer peripheral edge of the lock plate 23 ′ whose diameter has been increased, so that the lock pin 28 is unlocked via the screw shaft 33. I will be immersed in the position. When the lock lever 22 rides on the outer peripheral edge of the lock plate 23 'whose diameter has been increased, the unlocked state of the lock pin 28 is maintained.

Thus, after the first auxiliary seat back lock mechanism 51 is unlocked, the lock pin 28 of the second auxiliary seat back lock mechanism 52 is unlocked in conjunction with the forward tilt of the auxiliary seat back 2A. As a result, the two lock mechanisms 51 and 52 can be unlocked by one unlocking operation (one action), so that the operability is improved.

  Further, since the second auxiliary seat back lock mechanism 52 can be constituted by the lock pin 28, the lock hole 29a, the lock lever 22, and the lock plate 23 ', the structure is very simple, the operation reliability is high, and the manufacturing cost is low. become. The first auxiliary seat back lock mechanism 51 may employ a known inexpensive catch mechanism 54 such as a striker 53 and a fork.

1A is a perspective view of an auxiliary seat back in an upright position, FIG. 2B is a perspective view of an auxiliary seat back in a forward position, and FIG. 2C is a perspective view of an auxiliary seat back in a side standing position. is there. (A) is an assembly perspective view of a back frame and an auxiliary back frame, (b) is a perspective view of the locking mechanism of the first embodiment of the auxiliary seat back. It is a disassembled perspective view of the locking mechanism of an auxiliary seat back. (A) is side sectional drawing of the structure which fixes an outer pipe to the 2nd axis | shaft, (b) is a perspective view of the spring hooking plate of a lock pin. (A) (b) is a perspective view of the position control structure of an auxiliary seat back, respectively. It is a lock mechanism, (a) is a side view of the standing position, (b) is a side view of the forward position. FIG. 5A is a perspective view of the standing position, FIG. 5B is a perspective view of the forward position, and FIG. 5C is a perspective view of the side position. It is a principal part enlarged view of an auxiliary seat back and a lock mechanism, (a) is a perspective view of a standing position, (b) is a perspective view of a forward-falling position, and (c) is a perspective view of a side standing position. (A) is a perspective view which shows the relationship between the back frame provided with the locking mechanism of 2nd Embodiment, and an auxiliary back frame, (b) is a side view of the standing position of a locking mechanism, (c) is the front of a locking mechanism It is a side view of a fall position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle seat 1A Seat back 2 Auxiliary seat 2A Auxiliary seat back 5 Lock mechanism 12 1st shaft member 13 2nd shaft member 14 2nd shaft 20 2nd shaft member lock mechanism 22 Lock lever 23, 23 'Lock plate 23c Lock recessed part 23d Position restriction groove 24 Stopper pin 26 Auxiliary seat back lock mechanism 28 Lock pin 29 Lower plate 29a Lock hole 29b Position restriction hole 31 Linking mechanism 33 Screw shaft 34 Spring 44 Stopper pin 45 Resin receiver 45b Position restriction hole 45e Moderation protrusion 50 Lock mechanism 51 First auxiliary seat back lock mechanism 52 Second auxiliary seat back lock mechanism 53 Strike 54 Catch mechanism

Claims (8)

An auxiliary seat back that can be tilted between a standing position in a seat back state, a forward position in an armrest state, and a side standing position in a walk-through state on the side of the seat back of the seat,
A first shaft member fixed to the side portion of the seat back, a second shaft member supported by the first shaft member so as to be able to turn back and forth, and an auxiliary seat supported by the second shaft member so as to be turned left and right. The auxiliary seat back is tilted back and forth between the standing position and the forward tilt position by the first shaft member, and the auxiliary seat back is movable between the forward tilt position and the side standing position by the second shaft member. And a second shaft member locking mechanism that locks the second shaft member to the first shaft member at an upright position of the auxiliary seat back, and an auxiliary seat that locks the auxiliary seat back to the second shaft member An auxiliary seat back locking mechanism, wherein a back locking mechanism is provided, and a linkage mechanism that unlocks the other locking mechanism in association with an unlocking operation of one of the locking mechanisms is provided. The second shaft member locking mechanism is provided on the second shaft member, and can be pivoted between a lock position and an unlock position. The second shaft member lock mechanism is fixed to a side portion of the seat back so that the auxiliary seat back is raised. The lock recess with which the lock lever engages is configured with a lock plate formed on the outer peripheral edge,
The auxiliary seat back lock mechanism is provided on the second shaft member and can be moved into and out of the lock position and the unlock position. The auxiliary seat back lock mechanism is provided on the auxiliary seat back and the lock pin is engaged at the standing position of the auxiliary seat back. It consists of a lock hole that fits together,
The lock lever and the lock pin are linked by a linkage mechanism that simultaneously locks or unlocks, and when the lock lever is unlocked and the auxiliary seat back is tilted forward, the lock lever is moved to the outer periphery of the lock plate. The auxiliary seat back locking mechanism according to claim 1, wherein the unlocked state is maintained together with the lock pin. An auxiliary seat back that can be tilted to a standing position, a forward position, and a side position at a side of the seat back of the seat,
A first shaft member fixed to the side portion of the seat back, a second shaft member supported by the first shaft member so as to be able to turn back and forth, and an auxiliary seat supported by the second shaft member so as to be turned left and right. The auxiliary seat back is a first shaft member, and can be tilted back and forth between the standing position in the seat back state and the forward position in the armrest state. A first auxiliary seat back locking mechanism that can tilt left and right between the position and the side standing position in the walk-through state and locks the auxiliary seat back to the seat back at the standing position of the auxiliary seat back; and a second shaft member auxiliary seat back and the second auxiliary seat back locking mechanism is provided to lock the, and the first auxiliary seat back locking mechanism to unlock operation auxiliary seat back in conjunction to tilted forward, the second auxiliary Auxiliary seat back locking mechanism, characterized in that the interlocking mechanism for unlocking the over-back locking mechanism is provided. The second auxiliary seat back lock mechanism is provided on the second shaft member and can be moved into and out of the lock position and the unlock position. The second auxiliary seat back lock mechanism is provided on the auxiliary seat back and is locked at the standing position of the auxiliary seat back. A lock hole that engages with each other, a lock lever that can swing between a lock position and an unlock position, and an outer peripheral edge that is fixed to the side portion of the seat back and gradually expands in the forward tilt direction of the auxiliary seat back. It is composed of a lock plate formed to
The lock lever and the lock pin are linked by a linkage that simultaneously locks or unlocks, and when the auxiliary seat back is tilted forward , the lock lever is unlocked and the lock lever expands the diameter of the lock plate. 4. The auxiliary seat back locking mechanism according to claim 3, wherein the unlocked state is maintained together with the lock pin by riding on the outer peripheral edge.   A position restricting groove having an angular range between an upright position and a forwardly tilted position of the auxiliary seat back is formed on the outer peripheral edge of the lock plate, and the second shaft member enters the position restricting groove to enter the position of the auxiliary seat back. The auxiliary seat back locking mechanism according to claim 2, wherein a stopper pin for stopping the rotation is provided.   The auxiliary seat back is formed with a position restriction hole in an angular range between the forward position of the auxiliary seat back and the side-standing position, and the second seat member enters the position restriction hole to rotate the auxiliary seat back. 6. The auxiliary seat back locking mechanism according to claim 2, wherein a stopper pin for stopping the movement is provided.   The auxiliary seat back according to claim 6, wherein the position restriction hole is formed with a moderation protrusion portion on which the stopper pin can get over at a forward position and a side standing position of the auxiliary seat back. Lock mechanism.   The common spring which urges | biases a lock lever and a lock pin to a lock position in any one of the said lock lever and a lock pin is provided, The any one of Claim 2, 4-7 characterized by the above-mentioned. Auxiliary seat back locking mechanism.

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