JP2009214665A - Headrest operation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the degree of freedom of design of respective mechanism parts of a headrest operation device arranged in a seat back. <P>SOLUTION: A pressure receiving mechanism 20 arranged in the seat back 2 detects the occurrence of a vehicle rear collision as a moving distance at which a pressure receiving plate 22 is pushingly moved to the rear side. A support part 4A of a headrest 4 is operated toward a head part of a sitter by transmitting this moving distance to a headrest moving mechanism 10 via towing operation of an operation cable 40. The operation cable 40 is towed and operated by movably operating a connection point of the pressure receiving plate 22 and an outer cable 42 to a connection point of an inner cable 41 and a base board 2B to the moving distance at which the pressure receiving plate 22 is push-moved. The inner cable 41 is put in a state of not making a fixed state to the base board 2B function before the vehicle rear collision is caused, and follows the movement of the outer cable 42, but is put in a state of being fixed to the base board 2B when the vehicle rear collision is caused. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a headrest operating device. More specifically, the present invention relates to a headrest actuating device that operates so that the headrest can be moved close to a seated person's head when a rear collision of the vehicle is detected.

  2. Description of the Related Art Conventionally, some vehicle seats include a mechanism that supports a head by instantaneously moving a headrest toward a seated person's head when a vehicle rear-end collision occurs. Here, the following Patent Document 1 discloses a mechanism in which the headrest is operated and operated by a load that the seat occupant strongly presses against the seat back when the rear collision of the vehicle occurs. ing.

In this disclosure, the pressure receiving mechanism in the seat back is configured to operate only when the rear collision of the vehicle occurs, so that the headrest does not operate erroneously even if the seated person leans against the seat back in a normal state. It has become. Specifically, the pressure receiving mechanism described above is connected to a weight that performs inertial movement when a vehicle rear-end collision occurs, and the lock mechanism that prevents malfunction of the headrest is not released unless the inertial movement of the weight is performed. It is like that.
JP 2005-95237 A

  However, in the related art disclosed above, the pressure receiving mechanism, the lock mechanism, and the collision detection mechanism are arranged adjacent to each other through a mutually linked configuration relationship, so that the degree of freedom in design of each mechanism component is low. .

  The present invention was devised as a solution to the above-described problems, and the problem to be solved by the present invention is that the degree of freedom in the design of each mechanical component of the headrest actuator arranged in the seat back. It is to be able to raise.

In order to solve the above problems, the headrest actuating device of the present invention takes the following means.
First, the first invention is a headrest operating device that operates so that the headrest is moved close to the seated person's head when a vehicle rear-end collision is detected. A pressure receiving mechanism that detects the occurrence of a rear collision of the vehicle as a mechanical operation movement amount that is pushed and moved by the back of the seated person that leans backward by the spring is disposed inside the seat back. The mechanical operation movement amount detected by the pressure receiving mechanism is transmitted to an operation mechanism that moves the headrest via a pulling operation of a cable connected to the pressure receiving mechanism, whereby the headrest is operated. The cable connected to the pressure receiving mechanism is connected to the fixed body by the mechanical operation movement detected by the pressure receiving mechanism by connecting the pressure receiving mechanism and the fixed body that is not linked to the pressure receiving mechanism. A traction operation is performed by a movement operation relative to the connection point. Of the connection points, the connection structure of at least one of the connection points is in a state in which the fixed state due to the connection does not function before the occurrence of the rear-end collision, and the mechanical operation movement amount is detected by the pressure receiving mechanism. In this case, the relative movement between the two connection points is not performed. A relative motion between the connection points is performed.

  According to the first aspect of the invention, transmission of the operating force from the pressure receiving mechanism to the operating mechanism that moves the headrest is performed through a pulling operation of the cable that connects the pressure receiving mechanism and the operating mechanism. This cable is pulled by the mechanical operation movement detected by the pressure receiving mechanism at the time of rear collision of the vehicle by the connection structure to the pressure receiving mechanism and the connection structure to the fixed body. The operation of the headrest is prevented by absorbing the operation movement amount that the pressure receiving mechanism is pushed and moved in a state in which the fixed state by at least one of the connections is not functioned. Therefore, the pressure receiving mechanism and other mechanical parts related to the pressure receiving mechanism can be spaced apart from each other via the cable, and can be arranged in a relatively free position, and the degree of freedom in designing them can be increased.

  Next, according to a second aspect of the present invention, in the first aspect, the pressure receiving mechanism is configured such that the pressure receiving plate provided on the frame portion of the seat back so as to be swingable in the front-rear direction receives a backrest load of the seated person. It is configured to detect the amount of mechanical operation movement when pushed backward. The pressure receiving plate is connected to the skeleton of the seat back via a four-bar linkage mechanism, and the cable and the fixed body are connected by the link movement of the four-bar linkage mechanism as it moves rearward. It is configured to move in a direction away from the point.

  According to the second aspect of the invention, the pressure receiving plate swings along with the link movement of the four-bar linkage mechanism by the movement pushed backward, and moves in a direction away from the connection point between the cable and the fixed body. . As a result, the relative movement between the two connection points can be performed more efficiently, and a large amount of cable pulling operation can be ensured. Further, since the pressure receiving plate is connected to the skeleton of the seat back via the four-bar linkage mechanism, the pressure receiving plate can be oscillated in a stable posture state without wobbling the pressure receiving plate.

  Next, according to a third invention, in the first or second invention described above, the cable has a double structure in which a wire-like inner cable is inserted into a tubular outer cable. The end of the outer cable is connected and fixed to the pressure receiving mechanism. And the edge part of the inner cable pulled out from the edge part of an outer cable is connected and fixed to the moving member connected with the fixed body so that relative movement was possible. Before the occurrence of a vehicle rear-end collision, the relative movement of the moving member is allowed, and the end of the inner cable follows the movement of the end of the outer cable so that the cable is not pulled. However, when a vehicle rear-end collision occurs, the relative movement of the moving member is restricted by the switching mechanism, so that the end of the outer cable is moved with respect to the end of the inner cable held at a fixed position. It will be in the state where traction operation of is performed.

  According to the third aspect of the present invention, the end portion of the outer cable connected to the moving member is allowed to move relative to the end portion of the outer cable before the rear collision of the vehicle occurs. Follow. Therefore, even if the pressure receiving mechanism is pushed and moved, the cable is not pulled. However, when the rear collision of the vehicle occurs, the movement member is in a state where movement relative to the fixed body is restricted by the switching mechanism. Thereby, the end of the inner cable is held at a fixed position, and the cable is pulled by the movement of the end of the outer cable. In this manner, a mechanism for preventing malfunction of the headrest can be realized and configured.

Next, according to a fourth aspect, in the third aspect described above, the moving member is urged by the urging member in a moving direction that separates the end portion of the inner cable from the end portion of the outer cable.
According to the fourth invention, even if the cable is loosely routed due to variations in the length of the inner cable to be routed, the slack of the inner cable is removed along with the urging movement of the moving member, The inner cable can be wired in a stable position so that it does not come off or interfere with other components.

  Embodiments of the best mode for carrying out the present invention will be described below with reference to the drawings.

  First, the configuration of the headrest operating device according to the first embodiment will be described with reference to FIGS. Here, FIG. 1 shows a schematic configuration of a vehicle seat 1 on which the headrest actuating device of this embodiment is mounted. The vehicle seat 1 includes a seat back 2 that serves as a backrest, a seat cushion 3 that serves as a seating portion, and a headrest 4 that serves as a headrest. The vehicle seat 1 is configured so that the headrest 4 can be instantaneously moved toward the seated person's head when a vehicle rear-end collision occurs due to the configuration of the headrest operating device described later. In each drawing such as FIG. 1, these skin structures are omitted in order to easily show the internal structure of the headrest 4 and the seat back 2.

  Here, the headrest 4 has two rod-like stays 4B, 4B erected at the lower part thereof, which are inserted into the cylinders of the cylindrical supports 2S, 2S installed on the upper surface of the seat back 2, respectively. Therefore, it is mounted and supported on the upper surface of the seat back 2. These supports 2S and 2S are provided integrally fixed to the upper arm portion (upper frame Fu) of the gate-type back frame 2F forming the skeleton of the seat back 2. The upper frame Fu is configured to connect the upper ends of both side frames Fs, Fs of the back frame 2F, and is integrally coupled to both side frames Fs, Fs.

  The headrest 4 described above is normally held in a state where it is installed at an upper portion of the seat back 2, and is in a state where the head of the seated person can be received at a position on the rear side thereof. However, the headrest 4 can be brought close to the head by instantaneously moving only the front-side support portion 4A that receives the head of the headrest 4 to the front side when a vehicle rearward collision occurs. As a result, when a vehicle rear-end collision occurs, only the support portion 4A of the headrest 4 is preceded immediately behind the head with respect to a seated person who is in a posture of lifting the body forward from the headrest 4 or the seat back 2. It is possible to approach to the side position, and the movement of the head tilting backward due to the momentum of the rear collision can be stopped early. As a result, the load on the neck of the seated person can be reduced, so that whipping can be prevented.

  The operation of moving the support portion 4A to the front side when a rear collision occurs is performed by the headrest moving mechanism 10 incorporated in the headrest 4. Here, the headrest moving mechanism 10 corresponds to the operating mechanism of the present invention. As shown in FIG. 10, the headrest moving mechanism 10 locks and holds the support portion 4A in the initial position at all times before a vehicle rear-end collision occurs. Here, the support portion 4A is always urged in the moving direction on the front side close to the head by the urging force of the tension spring 16 hooked between the headrest base portion 4C serving as the main body of the headrest 4. Has been. However, the support portion 4A is locked and held at the initial position against the urging of the tension spring 16 at all times before the vehicle rear-end collision occurs.

  Then, the headrest moving mechanism 10 moves the support portion 4A to the front side by the urging force of the tension spring 16 by releasing the state where the support portion 4A is held at the initial position with the occurrence of the rear collision of the vehicle. It is like that. Here, the forward movement of the support portion 4A is obliquely moved upward along the shape of the long holes 11H and 11H formed in the headrest base portion 4C. Thereby, as shown in FIG. 12, the support portion 4A can be moved closer to a position closer to the rear side of the head (collision corresponding position).

  Here, the headrest moving mechanism 10 moves the support portion 4A to the above-described collision response position, so that the support portion 4A is moved backward even if a backward tilting load is applied to the support portion 4A due to the occurrence of a rear collision. It is not pushed back to the side. Thereby, when a rear collision occurs, the head is stably received at the collision corresponding position by the support portion 4A.

  Returning to FIG. 1, the operation of releasing the holding state of the support portion 4 </ b> A at the initial position at the time of rearward collision of the vehicle is an operation of pushing up the push rod 50 inserted into the stay 4 </ b> B on the right side of the headrest 4. Is done by. As shown in FIG. 2, the upper end of the push rod 50 is connected to an operation member 15 provided for unlocking the headrest moving mechanism 10. The lower end portion of the push rod 50 is connected to the upper end portion of the operation cable 40 arranged in the seat back 2. Here, the operation cable 40 corresponds to the cable of the present invention.

  As shown in FIG. 3, the operation cable 40 has a pressure receiving plate of the pressure receiving mechanism 20 whose lower end portion of the tubular outer cable 42 is a vehicle rear collision detection mechanism disposed in a seat back 2 described later. It is fixed to 22 and fixed. Then, the lower end portion of the linear inner cable 41 drawn out from the pipe on the lower end side of the outer cable 42 is hooked and fixed to the operation arm 31 of the switching mechanism 30 disposed at the lower position of the pressure receiving plate 22. Has been. Here, the operation arm 31 corresponds to the moving member of the present invention.

  Here, the pressure receiving mechanism 20 includes a formed wire 21 extending vertically in the center position of the seat back 2 and a pressure receiving plate 22 disposed at the lower abdomen position applied to the waist of the seated person. Configured. In the pressure receiving mechanism 20, when the vehicle rear-end collision occurs, the pressure-receiving plate 22 is pushed backward by the back of the seated occupant due to the spring, so that the pressure receiving plate 22 pushes the occurrence of the vehicle rear-end collision. It is the structure which detects as operation amount performed.

  Specifically, as shown in FIG. 1, the above-described formed wire 21 is formed by bending a single wire member into a frame shape so as to be applied to the back or waist of the seated person. The left and right end portions aligned on the upper end side of the formed wire 21 are only in the height direction by the clips Cr and Cr with respect to the upper reinforcing plate 2U spanned between the side frames Fs and Fs. It is in a state where it can move.

  The formed wire 21 has its lower frame-shaped portion always pushed forward by the urging force of the bending springs 2T and 2T hooked between the lower reinforcing plate 2D and its front surface. The posture is applied to the cushion pad 2C (see FIG. 3) disposed on the side. Here, returning to FIG. 1, the bending springs 2T and 2T are respectively hooked to the cut and raised portions Dc and Dc formed on the lower reinforcing plate 2D at the rear end side of the bent springs 2T and 2T. The portion on the front end side in the figure is integrally joined and fixed to the frame shape portion of the formed wire 21.

  As a result, when the seated person receives a load on the seat back 2, the formed wire 21 is pushed and moved rearward around the upper fulcrum (support point by the clips Cr and Cr) to bend and deform. In addition, the back of the seated person can be elastically supported.

  Next, the pressure receiving plate 22 can be rotated by the first arm 22A and the second arm 22B to the substrate 2B fixedly installed on the lower reinforcing plate 2D spanned between both side frames Fs and Fs of the back frame 2F. Are linked and provided. Here, the substrate 2B corresponds to the fixed body of the present invention. The first arm 22A and the second arm 22B described above are provided as a pair of left and right, and constitute a four-bar linkage mechanism in which the pressure receiving plate 22 and the substrate 2B are opposed to each other. Here, both arms 22A and 22B are pivotally connected to the pressure receiving plate 22 by connecting shafts Aa and Ba, respectively, and are rotatably supported to the substrate 2B by connecting shafts Ab and Bb. It is connected. The arms 22A and 22B are normally urged to rotate by the urging force of the torsion spring Bs hooked on the connecting portion between the second arm 22B and the substrate 2B, and the pressure receiving plate 22 is disposed on the front side thereof. The cushion pad 2C (refer to FIG. 3) pressed is held in a rotated posture state.

  Thereby, the pressure receiving plate 22 is normally held in a posture state in which the surface is directed to the front side of the seat back 2. As shown in FIGS. 4 to 5, the pressure receiving plate 22 receives the load that the seated person leans against the seat back 2, and thus the above-described urging is performed with the link motion of both the arms 22 </ b> A and 22 </ b> B. In contrast, it swings backward and upward. Here, returning to FIG. 3, the lower end portion of the outer cable 42 of the operation cable 40 described above is hooked and fixed to the back surface portion of the pressure receiving plate 22 described above.

  The inner cable 41 drawn out from the lower end portion of the outer cable 42 has its lower end portion hooked and fixed to an operation arm 31 that is spaced apart from the pressure receiving plate 22. As will be described in detail later, the operation arm 31 is locked in rotation with respect to the substrate 2B when a vehicle rear-end collision occurs (see FIG. 4). Is allowed.

  Thereby, as shown in FIG. 4, the operation cable 40 is fixed at a fixed position with respect to the substrate 2B as the pressure receiving plate 22 is moved rearward and upward when a vehicle rearward collision occurs. The lower end portion of the outer cable 42 is transferred by the pressure receiving plate 22 with respect to the lower end portion of the inner cable 41, and the inner cable 41 is pulled and operated in a fashion of being pulled out from the outer cable 42.

  Here, when the pressure receiving plate 22 moves to the rear side, the upper direction in which the inner cable 41 extends (the direction away from the lower end connection point of the inner cable 41) is accompanied by the link movement of both the arms 22A and 22B described above. It is also designed to move greatly. Thereby, the operation cable 40 is pulled out more efficiently from the lower end portion of the outer cable 42 as the pressure receiving plate 22 moves rearward, so that the operation cable 40 is pulled.

  However, as shown in FIG. 5, the operation cable 40 is allowed to rotate with respect to the substrate 2 </ b> B of the operation arm 31 as described above before the occurrence of the rearward collision of the vehicle. So that the lower end of the inner cable 41 moves following the movement of the outer cable 42 so that the traction operation as described above is not performed. It has become. Here, the inner cable 41 is normally urged to rotate in the counterclockwise direction shown in the figure by the urging force of a torsion spring 31S that is hooked to a connecting portion between the operation arm 31 and the substrate 2B described later. In response to the acting force, it is considered to be a tensioned state with no slack.

  Therefore, when the operation arm 31 is not rotationally locked, the inner cable 41 receives the acting force that moves the lower end of the outer cable 42 together with the pressure receiving plate 22 as described above. And move with the outer cable 42. Next, returning to FIG. 3, the configuration of the switching mechanism 30 that switches the fixed state of the lower end portion of the inner cable 41 with respect to the substrate 2B before and after the occurrence of the above-described vehicle rear-end collision will be described.

  The switching mechanism 30 includes an operation arm 31 that is pivotally coupled to the substrate 2B so as to be rotatable, and a pendulum 32 that can lock the rotation of the operation arm 31. Here, the operating arm 31 is pivotally connected to the substrate 2B by the connecting shaft Bb that connects the second arm 22B and the substrate 2B described above, and is attached to a tip portion away from the connecting shaft Bb. The lower end portion of the inner cable 41 is hooked and fixed. The operation arm 31 is normally urged to rotate counterclockwise in the figure by the urging force of the torsion spring 31S hooked to the connecting portion of the connecting shaft Bb with the substrate 2B.

  As a result, the operation arm 31 normally holds the inner cable 41 in a tensioned state without any slack, with the inner cable 41 being pulled in the direction of pulling out from the lower end of the outer cable 42. The torsion spring 31S that rotationally biases the operating arm 31 exerts a biasing force to such an extent that the inner cable 41 can be tensioned, and depending on the biasing force, the inner cable 41 has a lower end portion of the outer cable 42. Is not drawn from.

  On the other hand, the pendulum 32 is formed in an arm shape longer than the operation arm 31 described above, and an upper end portion thereof is rotatable with respect to the substrate 2B by the connecting shaft Ab connecting the first arm 22A and the substrate 2B. It is pivotally connected. A weight 32C is attached to the lower end of the pendulum 32. The weight 32C can apply a rotational bias with a spring to the pendulum 32 by the action of inertia when a rear-end collision occurs.

  The above-described pendulum 32 is normally rotated in the clockwise direction by the urging force of the torsion spring 32S hooked between the substrate 2B and the weight 32C is swung to the left in the figure. It is held elastically in the state. As a result, as shown in FIG. 4, the pendulum 32 is bounced by the weight 32C and rotated in the counterclockwise direction as shown in FIG.

  Here, the pendulum 32 is formed with a stopper piece 32B protruding like a plate piece, and this stopper piece 32B is inserted into a long hole Bh formed through the substrate 2B. . As a result, the pendulum 32 is normally held in a state where the stopper piece 32B is rotationally stopped at the position where the stopper piece 32B is pressed against the left end surface of the long hole Bh by the biasing force of the torsion spring 32S described above.

  However, as shown in FIG. 4, the pendulum 32 described above is struck by the weight 32 </ b> C attached to the lower end portion thereof when the rear collision of the vehicle occurs, and rotates in the counterclockwise direction shown in the drawing. ing. Here, returning to FIG. 3, a plurality of locking claws 31 </ b> C projecting radially outward are formed on the outer peripheral surface of the rotation center portion of the operation arm 31 described above. As shown in FIG. 5, the locking claw 31 </ b> C is always at a position where the pendulum 32 is rotated in the clockwise direction in the figure before the rearward collision of the vehicle. Even if the operation arm 31 is rotated in the clockwise direction in the figure by the force with which the part tries to follow the movement of the outer cable 42, it does not interfere with the stopper piece 32 </ b> B of the pendulum 32.

  Therefore, even if the occupant leans on the seat back 2 and the outer cable 42 is moved before the rear collision of the vehicle occurs, this operation movement amount is an operation arm that rotates and follows the movement of the outer cable 42. 31 (the lower end portion of the inner cable 41) is absorbed, and the pulling operation in which the inner cable 41 is pulled out from the lower end portion of the outer cable 42 is not performed.

  However, as shown in FIG. 4, in the locking claw 31 </ b> C, the pendulum 32 rotates counterclockwise in the figure due to the occurrence of a rearward collision of the vehicle, and the stopper piece 32 </ b> B moves to the right in the figure in the elongated hole Bh. As a result, one of the claws contacts the stopper piece 32B with respect to the clockwise rotation of the operation arm 31. Thereby, even if the lower end part of the inner cable 41 receives the effect | action of the force which follows the movement of the outer cable 42, the operation arm 31 is the contact | abutting with the latching claw 31C and the stopper piece 32B mentioned above, The rotational movement is restricted.

  As a result, the operation cable 40 moves rearward and upward with the lower end of the outer cable 42 following the movement of the pressure receiving plate 22 with respect to the lower end of the inner cable 41 held at a fixed position with respect to the substrate 2B. The inner cable 41 is pulled out from the lower end portion of the outer cable 42 by this movement. As a result, the amount of movement of the inner cable 41 that has been pulled is transmitted as the amount of movement of the push rod 50 described above with reference to FIG. 2, and the headrest 4 is actuated.

  Note that the operation of locking the rotation of the operation arm 31 by rotating the pendulum 32 shown in FIG. Is performed prior to the operation of leaning on the seat back 2.

  As described above, in the headrest actuating device of the present embodiment, the operation arm 31 connected to the lower end portion of the inner cable 41 can be rotationally locked with respect to the board 2B only when a vehicle rear-end collision occurs. Even if a person applies a strong load to the seat back 2 by pressing the elbow strongly against the seat back 2 during normal seating use, the headrest 4 does not operate erroneously. Also, during normal seating use, the amount of operation movement of the outer cable 42 can be absorbed and released by the follow-up rotation of the operation arm 31, so that the inner cable 41 and other components related thereto can be released. An abnormal load can be prevented.

  Next, a structure in which operating force is transmitted from the operating cable 40 to the push rod 50 will be described. Here, the operation cable 40 has a double structure in which a linear inner cable 41 that is more flexible than the outer cable 42 is inserted inside a tubular outer cable 42 having flexibility. As described above with reference to FIG. 3, the lower end of the outer cable 42 is secured to the operation cable 40 by being hooked on the pressure receiving plate 22, and the inner cable is drawn from the lower end of the outer cable 42. The lower end portion of 41 is hooked and fixed to the operation arm 31.

  As a result, the operation cable 40 is towed in such a manner that the inner cable 41 is pulled out from the lower end of the outer cable 42 when a vehicle rear-end collision occurs. Here, as shown in FIG. 1, the operation cable 40 is routed inside the shape of the seat back 2, and is tied to the formed wire 21 by the binding band B so that its routing position is fixed. ing.

  Then, as shown in FIG. 2, the operation cable 40 is inserted into the support 2S cylinder from the lower side, so that the upper end of the operation cable 40 is inserted into the support 2S cylinder from the upper side. The push rod 50 is assembled so that it can be pushed. Here, the operation cable 40 has T-shaped engagement protrusions 41P and 41P formed at the upper end portion of the inner cable 41 through elongated holes 42S and 42S formed through the peripheral wall on the upper end side of the outer cable 42, respectively. The structure protrudes outward in the radial direction.

  As a result, the inner cable 41 is pivoted with respect to the outer cable 42 within a range in which the engagement protrusions 41P and 41P projecting in a T shape are movable in the axial direction within the long holes 42S and 42S. It can be moved in the direction. The engagement protrusions 41P and 41P and the long holes 42S and 42S are formed at two locations in the circumferential direction that are symmetrical about the inner cable 41 and the outer cable 42. And the head part 42H of the shape which plugs up the tubular edge part shape is formed in the upper end part of the outer cable 42. As shown in FIG.

  As shown in FIG. 6, the operation cable 40 having the above configuration is temporarily held in a state where the upper end is suspended from the support 2S by inserting the upper end into the cylinder of the support 2S from below. (See FIG. 7). In this suspended state, the stay 4B is inserted into the cylinder of the support 2S from above, so that the operation cable 40 is shifted from the state suspended from the support 2S to the state suspended from the stay 4B. It has become so.

  Then, when the operation cable 40 is shifted to the state suspended by the stay 4B in this way, the operation cable 40 is inserted into the stay 4B by the operation force (operation movement amount) pulled on the lower end side thereof. The push rod 50 can be transmitted in the reverse direction as the push operation force (push operation amount). That is, the operation cable 40 and the push rod 50 are connected to each other so as to transmit the operation force.

  Hereinafter, a configuration in which the operation cable 40 and the push rod 50 described above are coupled so as to be able to transmit the operation force to each other will be described. Here, as shown in FIG. 6, insertion holes Sd and Sd extending in a slit shape in the axial direction from the lower end of the support 2 </ b> S upward are formed through the peripheral wall of the support 2 </ b> S. These insertion holes Sd and Sd are formed in two axially symmetrical shapes in the circumferential direction of the support 2S.

  The insertion holes Sd and Sd can receive the engaging protrusions 41P and 41P formed on the inner cable 41 in the axial direction as the operation cable 40 is inserted into the cylinder of the support 2S. ing. Here, each insertion hole Sd, Sd is formed such that the shape of the upper end side in the figure serving as the terminal end thereof is curved in the left direction and right direction in the figure as the circumferential direction.

  Specifically, the insertion hole Sd indicated by a solid line on the front side of the sheet of FIG. 6 has a shape in which a terminal portion is curved leftward in the drawing. The insertion hole Sd indicated by a broken line on the back side has a shape in which a terminal portion is curved rightward in the drawing and is axially symmetric with respect to the insertion hole Sd on the near side. Here, the end portion shape of each insertion hole Sd, Sd is formed in a shape that hangs downward from the horizontal. Thereby, each engagement protrusion 41P and 41P are penetrated to the termination | terminus part of each insertion hole Sd and Sd, and each engagement protrusion 41P and 41P (operation cable 40) does not fall below by own weight. It is held in a state suspended from the support 2S as a state.

  Here, the upper end portion of the outer cable 42 is formed of a synthetic resin, and a guide portion 42D having a shape that bulges outward in the radial direction is formed at an intermediate position. The guide portion 42D is formed in a serrated shape that is repeatedly concave and convex in the circumferential direction, and has an outer diameter dimension that matches the inner diameter dimension of the support 2S. Thus, when the operation cable 40 is inserted into the cylinder of the support 2S, the guide portion 42D is gently applied to the in-cylinder shape of the support 2S without causing the insertion movement of the operation cable 40 to flutter. It can be done smoothly.

  On the other hand, as shown in FIG. 7, the peripheral wall of the stay 4B inserted from above into the cylinder of the support 2S has a receiving hole Bd extending in a slit shape in the axial direction from its lower end to the upper side. Bd is formed through. These receiving holes Bd, Bd are formed in two axially symmetrical shapes in the circumferential direction of the stay 4B. The receiving holes Bd and Bd are formed by inserting the stay 4B into the cylinder of the support 2S from above so that the engagement protrusions 41P and 41P of the inner cable 41 suspended in the cylinder of the support 2S Accept inside the hole.

  Then, by further inserting the stay 4B into the cylinder of the support 2S from this state, the engaging protrusions 41P and 41P are inserted upward along the shapes of the receiving holes Bd and Bd. Here, each receiving hole Bd, Bd has a shape on the upper end side in the figure, which is a terminal side thereof, curved in a circumferential direction opposite to each insertion hole Sd, Sd formed in the support 2S described above. Is formed.

  The shape of the receiving holes Bd and Bd that curves in the circumferential direction is formed into a shape that curves gently and smoothly from the axial direction to the horizontal direction. As a result, the receiving holes Bd and Bd turn the engaging protrusions 41P and 41P in the cylinder of the support 2S in the horizontal direction by an axial pushing operation force for inserting the stay 4B into the cylinder of the support 2S. It can be moved smoothly to the end position.

  Therefore, by inserting the stay 4B into the cylinder of the support 2S, the engagement protrusions 41P and 41P are guided by the curved shapes of the receiving holes Bd and Bd formed in the stay 4B described above, while the support 2S The insertion holes Sd and Sd are pulled back in the opposite circumferential direction from the end position. The engaging protrusions 41P and 41P reach the curved end positions of the receiving holes Bd and Bd of the stay 4B as the insertion movement of the stay 4B further proceeds, and the insertion holes Sd and Sd of the support 2S. It will be in the state pulled back to the hole-shaped position extended in the axial direction of Sd.

  Thereby, each engagement protrusion 41P and 41P shifts from the state suspended from the support 2S to the state suspended from the stay 4B. As a result, the engagement protrusions 41P and 41P are in a state in which the movement in the axial direction relative to the stay 4B is restricted, instead of being allowed to move in the axial direction relative to the support 2S. At this time, the engagement protrusions 41P and 41P are located in the shape portions extending in the axial direction of the insertion holes Sd and Sd, and thus their movement in the circumferential direction is restricted (FIG. 8). reference).

  Thereby, each engagement protrusion 41P and 41P are in the state guided so that it might rotate from the terminal position of each receiving hole Bd and Bd in the circumferential direction, and may not fall off. As a result, the inner cable 41 and the stay 4B are integrally connected to each other in the axial direction, so that the inner cable 41 and the stay 4B can be moved together in the axial direction with respect to the support 2S.

  Here, as shown in FIG. 9, the stay 4 </ b> B is provided with a latching groove Bk formed in a concave shape on the outer peripheral wall thereof so as to protrude into the insertion port Sa of the support 2 </ b> S. The movement in the insertion direction is regulated by being latched to the latching claw St. Note that the movement restriction state in the insertion direction of the stay 4B by the locking claws St is released by pressing the knob Sb provided on the side portion on the upper end side of the support 2S.

  By the way, the lower end portion of the stay 4B and the upper end portion of the inner cable 41 are integrally connected to each other in the axial direction by the insertion operation of the stay 4B described above, so that the outer cable 42 is inserted into the pipe of the stay 4B. The head 42H is inserted from below. Thereby, the lower end part of the push rod 50 inserted and arranged in the pipe of the stay 4B and the head part 42H of the outer cable 42 are in a state of being arranged close to each other in the axial direction.

  Accordingly, when the inner cable 41 is pulled at the lower end side from this state, the push rod 50 is pushed up from the lower side by the head portion 42H of the outer cable 42 as shown in FIG. Operated. That is, the operation cable 40 is in a state in which the upper end portion of the inner cable 41 is integrally connected to the stay 4B in the axial direction by the above-described insertion operation of the stay 4B.

  On the other hand, the upper end portion (head portion 42 </ b> H) of the outer cable 42 is formed to be movable in the axial direction with respect to the inner cable 41. Accordingly, when the inner cable 41 is pulled at the lower end side, the upper end of the outer cable 42 is integrated with the stay 4B according to the operation movement amount that is pulled. It will be pushed upward relative to the upper end.

  As a result, as shown in FIG. 2, the operating force obtained by pulling the operation cable 40 during a rear-end collision of the vehicle can be transmitted to the push rod 50 inside the stay 4B as a pressing operation force. The operation member 15 provided for the unlocking operation can be released. Strictly speaking, a slight gap in the axial direction is set between the head portion 42H of the outer cable 42 and the lower end portion of the push rod 50 described above, and the push is erroneously performed when the stay 4B is inserted. The rod 50 is prevented from being pushed by hitting the head 42H of the outer cable 42.

  Next, the configuration of the headrest moving mechanism 10 will be described with reference to FIGS. The configuration of each part of the headrest moving mechanism 10 is best illustrated in FIG. 13, and the configuration of each part will be described with reference to FIG. 13. The headrest moving mechanism 10 is configured to be able to move the support portion 4A forward relative to the headrest base portion 4C when a vehicle rearward collision occurs.

  Specifically, the headrest moving mechanism 10 includes a pair of left and right link members 12 and 12 that link and connect the support portion 4A and the headrest base portion 4C, and a pair of left and right arms formed to extend rearward from the support portion 4A. The members 13, 13, the hooks 14, 14 for locking the support portion 4A in the initial position, the operation member 15 for releasing the lock state by the hooks 14, 14, and the direction for moving the support portion 4A forward And a lever member 17 and 17 for guiding when the support portion 4A is returned to the initial position.

  Here, the headrest base portion 4C is formed of a synthetic resin, and has a plate-like rear surface portion 11B, a bottom surface portion 11D, both side surface portions 11S and 11S, and an upper surface portion 11U. Specifically, the bottom surface portion 11D is formed in a shape extending forward from the edge on the lower end side of the rear surface portion 11B. And the side parts 11S and 11S are each standingly formed in each side part of the width direction of 4 C of headrest base parts. And the upper surface part 11U is formed in the shape which connects the edge parts of the upper end side of both the side surface parts 11S and 11S mentioned above.

  Here, FIG. 16 shows a view seen from the XVI line direction of FIG. 13, that is, a view of the headrest 4 seen from the obliquely lower side on the front side. As shown in the figure, a plurality of plate-like ribs 11R,... Are formed between the side surface portions 11S, 11S of the headrest base portion 4C so as to be parallel thereto, and the headrest base portion 4C is reinforced. Has been. Then, the upper end portions of the stays 4B and 4B are respectively inserted into the bottom surface portion 11D of the headrest base portion 4C and fixed integrally.

  These stays 4B and 4B are formed in a tubular shape, and are fixed in such a manner that the opening portion on the upper end side is exposed on the upper surface side of the bottom surface portion 11D. Returning to FIG. 13, long holes 11H and 11H penetrating in the plate thickness direction are formed in the side surface portions 11S and 11S of the headrest base portion 4C. These long holes 11H, 11H are formed in a first stopper groove H1, which is recessed in a wave-like shape on the rear side (right side in the drawing) between the lower end portions H0, H0 and the upper end portions H3, H3. H1 and second stopper grooves H2, H2 are respectively formed.

  Next, the pair of link members 12 and 12 are made of synthetic resin, and are configured as a connecting member that links the headrest base portion 4C and the support portion 4A. These link members 12, 12 are arranged side by side in the width direction, and are linked to a portion near the upper end side of the headrest base portion 4C and a portion on the rear surface side of the support portion 4A. Specifically, each link member 12, 12 is pivotally coupled at its rear end by a coupling shaft 12A provided through both side surfaces 11S, 11S of the headrest base 4C. .

  Here, as shown in FIG. 16, the link members 12, 12 have end portions on the rear side connected to the headrest base 4 </ b> C on both side surfaces 11 </ b> S, 11 </ b> S and ribs 11 </ b> R, 11 </ b> R on the inside thereof. Between the two. The link members 12, 12 are pivotally connected to a connecting shaft 12A inserted between the side surface portions 11S, 11S so as to be rotatable.

  Returning to FIG. 13, the front end portion connected to the support portion 4 </ b> A of each link member 12, 12 is connected to the connecting shaft 12 </ b> B extending in the width direction connected to the rear surface side portion of the support portion 4 </ b> A. Are pivotally connected to each other. These connecting shafts 12A and 12B are arranged extending in the width direction in parallel to each other. As can be seen with reference to FIG. 11, the link members 12, 12 described above are in contact with the upper surface portion 11 </ b> U of the headrest base portion 4 </ b> C by the rotational movement in the clockwise direction around the connecting shaft 12 </ b> A on the rear end side. Is now regulated.

  Next, returning to FIG. 13, the pair of arm members 13, 13 are formed to extend rearward from the rear surface portion of the support portion 4 </ b> A. The rear ends of these arm members 13 and 13 are connected to each other by a connecting shaft 13A extending in the width direction. Specifically, as shown in FIG. 16, the arm members 13, 13 have ribs 11 </ b> R, 11 </ b> R whose rear end portions are arranged and formed on both outer sides thereof and ribs 11 </ b> R, 11 </ b> R on the inner sides thereof. Between the two.

  Returning to FIG. 13, the connecting shaft 13A that connects the rear ends of the arm members 13 and 13 has long holes 11H and 11H in which each end is formed so as to penetrate the side surfaces 11S and 11S of the headrest base 4C. It is supposed to be inserted into the inside. As a result, the connecting shaft 13A can move in the front-rear direction (the left-right direction in the drawing) and in the up-down direction only within the range in which the long holes 11H, 11H can move. Each rib 11R (see FIG. 16) formed between the side surface portions 11S, 11S is formed in a shape that does not interfere with the connecting shaft 13A moving in the long holes 11H, 11H. Yes.

  Next, referring to FIG. 11, the hooks 14, 14 are formed in a cam shape, and are arranged side by side in the width direction at a position near the lower end side of the headrest base portion 4 </ b> C. The hooks 14 and 14 are configured to be able to hold the movement of the connecting shaft 13A moving in the long holes 11H and 11H described above at the lower end portions H0 and H0 that are the initial positions. Here, as shown in FIG. 16, the hooks 14 and 14 are disposed between the side surface portions 11S and 11S and the ribs 11R and 11R inside thereof, and are inserted between these. Each of the connected connecting shafts 14A and 14A is pivotally connected so as to be rotatable.

  Returning to FIG. 11, the upper jaw portions 14B and 14B and the lower jaw portions 14C and 14C projecting outward in the radial direction are formed at two circumferential positions of the outer peripheral edge portions of the hooks 14 and 14, respectively. Has been. As a result, a dent recessed inward in the radial direction is formed between each of the upper jaw portions 14B and 14B and the lower jaw portions 14C and 14C. And the connecting shaft 13A mentioned above is stored in the recess between these upper jaw parts 14B and 14B and lower jaw parts 14C and 14C.

  And the torsion springs 14S and 14S are respectively hooked between the hooks 14 and 14 and the headrest base 4C. These torsion springs 14S and 14S are assembled in a pre-twisted state and urge the hooks 14 and 14 to rotate in the counterclockwise direction shown in the figure from the position shown in FIG. And the locking grooves 14D and 14D which were depressed in the step shape are formed in the outer-periphery edge part of these hooks 14 and 14, respectively.

  A pair of engaging arm portions 15C and 15C, which are constituent members of the operation member 15 to be described later, are engaged with the locking grooves 14D and 14D, respectively. Thereby, each hook 14 and 14 is always hold | maintained as the state by which the rotation to the counterclockwise direction by the biasing was controlled. Therefore, the hooks 14 and 14 having the above-described configuration have the connecting shaft 13A in the recesses between the upper jaw portions 14B and 14B and the lower jaw portions 14C and 14C in a state where the rotation in the counterclockwise direction is restricted. As a sandwiched state, the connecting shaft 13A is held in a state of being engaged with the lower ends H0 and H0 of the long holes 11H and 11H.

  Here, as shown in FIG. 10, the connecting shaft 13A is normally urged by a tension spring 16 hooked between the connecting shaft 12A and the connecting shaft 12A so as to be drawn toward the connecting shaft 12A. It is in a state of being urged toward the upper end portions H3 and H3 along the shape of the long holes 11H and 11H. Accordingly, the connecting shaft 13A is normally locked to the lower end portions H0 and H0 of the long holes 11H and 11H by the hooks 14 and 14 against the urging force of the tension spring 16 (initial position state). Is held as.

  Returning to FIG. 11, the hooks 14, 14 are operated to rotate the engagement arm portions 15 C, 15 C in the counterclockwise direction shown in the figure, and the engagement state thereof is released, so that the torsion spring 14 S is released. , 14S is rotated counterclockwise by the urging force of 14S. As a result, as shown by the phantom lines in FIG. 11, the hooks 14 and 14 move the upper jaw portions 14B and 14B to the outside of the long holes 11H and 11H, and move the lower jaw portions 14C and 14C from the lower side. It will be in the attitude | position state exposed in the hole of the long holes 11H and 11H by pushing up.

  Accordingly, the locking state of the connecting shaft 13A by the hooks 14 and 14 is released, so that the connecting shaft 13A has a shape of the long holes 11H and 11H by the urging force of the tension spring 16 as shown in FIGS. And move forward and upward. As a result, the support portion 4A moves forward and upward with respect to the headrest base portion 4C while the link members 12 and 12 are rotated.

  Here, returning to FIG. 11, the engaging arm portions 15 </ b> C and 15 </ b> C that restrict the rotation of the hooks 14 and 14 in the illustrated counterclockwise direction are arranged in the width direction in accordance with the arrangement of the hooks 14 and 14. It is arranged. As shown in FIG. 16, the engaging arm portions 15C and 15C are arranged so as to be sandwiched between the side surface portions 11S and 11S and the ribs 11R and 11R located inside thereof as in the case of the hooks 14 and 14. Has been.

  The engaging arm portions 15C and 15C are pivotally connected to a connecting shaft 15B provided so as to penetrate between the side surface portions 11S and 11S. The connecting shaft 15B is integrally connected to the engaging arm portions 15C and 15C and is pivotally supported with respect to the side surface portions 11S and 11S. The connecting shaft 15B is disposed in parallel with the connecting shafts 12A and 12B and the connecting shaft 13A.

  A torsion spring 15S is hooked between the one engaging arm portion 15C and the headrest base portion 4C. The torsion spring 15S is assembled in a pre-twisted state, and as shown in FIG. 11, the respective engaging arm portions 15C and 15C are urged to rotate in the clockwise direction in the drawing. As a result, the engaging arm portions 15C and 15C are normally pressed against the outer peripheral surface portions of the hooks 14 and 14, and the locking grooves 14D are recessed at the tips of the hooks 14 and 14, respectively. , 14D are held in the engaged state. In a state in which these engagement arm portions 15C and 15C are engaged with the locking grooves 14D and 14D, respectively, the two are in abutment with each other, and the urging rotation of each other is regulated by each other. Yes.

  Returning to FIG. 11, the operating arm portion 15 </ b> A that is rotated by the push rod 50 is integrally connected to the end of the connecting shaft 15 </ b> B connected to the engaging arm portions 15 </ b> C and 15 </ b> C. Has been. The operating arm portion 15A is rotated in the counterclockwise direction in the drawing by the push rod 50 being pushed upward when a vehicle rearward collision occurs. As a result, the engaging arm portions 15C and 15C are integrally rotated with the operating arm portion 15A and rotated in the same direction, and are released from the engaged state with the hooks 14 and 14.

  As a result, the holding state of the support portion 4 </ b> A at the initial position is released, and the support portion 4 </ b> A is transferred forward and upward by the bias of the tension spring 16. The forward and upward movement of the support portion 4A is locked when the connecting shaft 13A reaches the upper end portions H3 and H3 of the long holes 11H and 11H, as shown in FIG. And in the state which movement of this support part 4A stopped, even if the support part 4A receives a load from a seated person's head, it is not pushed back backward.

  That is, when the connecting shaft 13A reaches the upper end portions H3 and H3 of the long holes 11H and 11H, the link members 12 and 12 connected to the support portion 4A come into contact with the upper surface portion 11U of the headrest base portion 4C. The rotation in the clockwise direction is restricted. In the state where the rotation of the link members 12 and 12 in the counterclockwise direction shown in the figure is restricted, even if a force that pushes and moves the support portion 4 </ b> A works, the force is applied to each link member 12. , 12 acts as a force in the direction of pressing the top surface portion 11U of the headrest base portion 4C. As a result, the support portion 4A is held in a state in which the head of the seated person can be received at the collision corresponding position without being pushed back to the rear side.

  Further, as shown in FIG. 12, the support portion 4A is not pushed back to the back side even if it is pressed by the seated person's head during the forward movement. That is, the first stopper groove in which the connecting shaft 13A is recessed to the rear side (right side in the drawing) of the long holes 11H and 11H when a force is applied to the support portion 4A so as to be pushed back in the middle of its forward movement. H1 and H1 and the second stopper grooves H2 and H2 enter and are locked.

  Accordingly, the movement of the connecting shaft 13A to be pushed back is restricted, and the support portion 4A is held in a posture state during the forward movement. Therefore, the head of the seated person can be stably received by the support portion 4A even at a midway position before reaching the collision corresponding position. FIG. 12 shows a state in which the connecting shaft 13A has entered the grooves of the second stopper grooves H2 and H2.

  Here, returning to FIG. 10, a pair of left and right arm-shaped lever members 17, 17 are disposed on the headrest base 4 </ b> C. These lever members 17 and 17 are arranged side by side in the width direction, and rear end portions thereof are pivotally connected to the headrest base portion 4C by connecting shafts 17A and 17A, respectively. Specifically, as shown in FIG. 16, the lever members 17, 17 have rear end portions between the ribs 11 </ b> R, 11 </ b> R arranged on both outer sides and the ribs 11 </ b> R, 11 </ b> R inside them. The shafts are pivotally connected to each other by connecting shafts 17A and 17A inserted between them.

  And the torsion springs 17S and 17S are respectively hooked between these lever members 17 and 17 and the headrest base 4C. As shown in FIG. 10, these torsion springs 17S, 17S are wound around the connecting shafts 17A, 17A, one end of which is hooked on the lever members 17, 17, and the other end is hooked on the headrest base 4C. It is worn. Thereby, the lever members 17 and 17 are hold | maintained in the attitude | position position exposed in the hole of the long holes 11H and 11H by the effect | action of the spring force of each torsion spring 17S and 17S in the free state.

  And the spoon-shaped receiving parts 17B and 17B are formed in the front-end | tip part of the left side of the figure exposed in the hole of the long holes 11H and 11H of each lever member 17 and 17, respectively. As shown in FIG. 12, these receiving portions 17B and 17B are pushed away when the connecting shaft 13A moves in the long holes 11H and 11H from the lower end portions H0 and H0 upward. The long holes 11H and 11H are pushed out of the holes in a cool manner. However, as shown in FIG. 13, the receiving portions 17B and 17B are long again by the spring action of the torsion springs 17S and 17S when the connecting shaft 13A reaches the upper end portions H3 and H3 of the long holes 11H and 11H. The postures exposed in the holes 11H and 11H are returned.

  As shown in FIG. 14, when the connecting shaft 13A is transferred from the upper end portions H3 and H3 downward from the upper end portions H3 and H3 to the receiving portions 17B and 17B, the connecting shaft 13A is moved to the tip side. Receive and catch in the shape of a spoon. Then, by moving the connecting shaft 13A further downward from this state, the lever members 17, 17 are rotated by the connecting shaft 13A caught by the receiving portions 17B, 17B in a counterclockwise direction as shown. To do.

  Accordingly, the connecting shaft 13A is moved and guided to the vicinity of the lower end portions H0 and H0 as shown in FIG. 15 while being moved and guided by the lever members 17 and 17, and is removed from the receiving portions 17B and 17B. Thus, when the connecting shaft 13A is transferred from the upper end portions H3, H3 downward in the elongated holes 11H, 11H, while being guided by movement by the lever members 17, 17, the first stopper grooves H1, The lower end portions H0 and H0 are smoothly transferred so as not to enter H1 and the second stopper grooves H2 and H2.

  The connecting shaft 13A is operated so as to push it into the lower end portions H0, H0 of the long holes 11H, 11H, whereby the lower jaw portions 14C of the hooks 14, 14 exposed at the lower end portions H0, H0. , 14C is pushed down to reach the lower end H0, H0. As a result, as shown in FIG. 11, the hooks 14 and 14 are pushed in the clockwise direction in the drawing, and the upper jaw portions 14B and 14B are turned to the upper side of the connecting shaft 13A.

  Then, when the hooks 14 and 14 are in the above posture state, the hooks 14 and 14 are engaged with the engaging arm portions 15C and 15C, and are locked again in a state where the connecting shaft 13A is held at the initial position (lower end portions H0 and H0). The As a result, the support portion 4A is again held in a state where it is returned to the initial position posture before moving forward.

  Next, the usage method of a present Example is demonstrated. That is, referring to FIG. 1, the vehicle seat 1 is in a state in which the support portion 4 </ b> A of the headrest 4 is held in the initial position at all times before the vehicle rear-end collision occurs. Then, when the rearward collision of the vehicle occurs, the pressure receiving plate 22 is pushed rearward by a backrest load that the seated person presses against the seat back 2, and this operating force is transmitted via the operation cable 40 and the push rod 50. Then, the operation member 15 is rotated.

  As a result, the holding state of the support portion 4A at the initial position is released, so that the support portion 4A is transferred to the collision corresponding position shown by the urging force of the tension spring 16 as shown in FIG. Then, by the support portion 4A that has moved to the collision-corresponding position, the head of the seated person who tilts backward due to the momentum of the rear impact is received at an early stage.

  As described above, according to the headrest actuating device of the present embodiment, the transmission of the operating force from the pressure receiving mechanism 20 to the headrest moving mechanism 10 is performed through the pulling operation of the operation cable 40 that couples them together. The operation cable 40 has a mechanical operation movement detected by the pressure receiving mechanism 20 at the time of rearward collision of the vehicle due to the connection structure of the outer cable 42 to the pressure receiving plate 22 and the connection structure of the inner cable 41 to the board 2B (operation arm 31). Although the tow operation is performed in response to the amount, before the vehicle rear-end collision occurs, the fixed state with respect to the substrate 2B is set to the non-functioning state, and the operation movement amount by which the pressure receiving mechanism 20 is pushed and moved is absorbed and the headrest 4 malfunctions. To prevent. Therefore, the pressure receiving mechanism 20 and other mechanical parts related to the pressure receiving mechanism 20 can be separated from each other via the operation cable 40 and can be arranged at a relatively free position, and the degree of freedom in designing them can be increased.

  Further, the pressure receiving plate 22 swings with the link movement of the four-bar linkage mechanism by the first arm 22A and the second arm 22B due to the movement pushed to the rear side, and the connection point between the inner cable 41 and the operation arm 31. Move away from the direction. Thereby, a large pulling operation amount of the operation cable 40 can be secured. Further, since the pressure receiving plate 22 is connected to the skeleton of the seat back 2 via the four-bar linkage mechanism, the pressure receiving plate 22 can be oscillated in a stable posture state without wobbling.

  Although the embodiment of the present invention has been described with one embodiment, the present invention can be implemented in various forms in addition to the above-described embodiment. For example, as disclosed in documents such as Japanese Patent Application Laid-Open No. 2005-104259, the support portion 4A of the headrest 4 is directly moved in the traveling direction by an amount corresponding to the amount of movement, depending on the amount of movement of the operation cable 40. As described above, the headrest moving mechanism can be configured.

  In addition, the operation arm 31 (moving member) has a locking claw 31C that engages with the stopper piece 32B of the pendulum 32 and has a plurality of claw-like claw shapes. A configuration having only one nail may be used. However, in this case, it should be noted that the rotation of the operation arm 31 can be stopped only at one rotation angle position where the locking claw 31C and the stopper piece 32B are engaged.

  Further, the movement mode of the operation arm 31 and the pendulum 32 constituting the switching mechanism 30 may be a direct acting type instead of a rotating type. Further, the movement of the switching mechanism 30 is not only the one that operates by the inertial movement using the pendulum 32, but an operation structure that locks the movement of the operation arm 31 by detecting the occurrence of the rear collision of the vehicle by, for example, electrical control. It may be.

  In addition, the switching mechanism 30 has been configured to switch between the outer cable 42 and the inner cable 41 and the circuit board 2B (fixed body) connected to each other when the rearward collision occurs and before the occurrence. The configuration may be such that the fixed state due to the connection with the pressure receiving plate 22 is switched so as not to function. Further, the operation cable 40 may be a cable in which the inner cable 41 is connected and fixed to the pressure receiving plate 22 and the outer cable 42 is connected and fixed to the substrate 2B.

FIG. 2 is a perspective view illustrating a schematic configuration of a headrest operating device according to the first embodiment. It is a block diagram showing a state in which the holding state at the initial position of the headrest is released when a rear collision occurs. It is the side view which showed the initial state of the guide mechanism. It is the side view which showed the movement of the guide mechanism when receiving a backrest load at the time of rear collision occurrence. It is the side view which showed the movement of the guide mechanism when receiving the backrest load at the normal time. It is a disassembled perspective view showing the insertion structure of a stay and an operation cable. It is a perspective view showing the state where the operation cable was inserted in the support. It is a perspective view showing the state where the stay was inserted into the inside of the support. It is the IX-IX sectional view taken on the line of FIG. It is a side view showing the state where the headrest was held in the initial position. It is the XI-XI sectional view taken on the line of FIG. 16 showing the internal structure of the headrest. It is a side view showing the state in the middle of the headrest moving to the front side. It is the side view showing the state where the headrest moved to the collision corresponding position. It is a side view showing the state in the middle of operation in which a headrest is returned to an initial position. It is a side view showing the state where the headrest is returned to the initial position while being guided. It is the block diagram which looked at the headrest from the XVI line direction of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle seat 2 Seat back 2F Back frame Fu Upper frame Fs Side frame 2S Support Sa Insertion slot Sb Knob St Locking claw Sd Insertion hole 2U Upper reinforcement board 2D Lower reinforcement board Dc Cut and raised part 2B Substrate (fixed body)
Bh Long hole B Binding band 2T Bending spring 2C Pad 3 Seat cushion 4 Headrest 4A Bearing 4B Stay Bk Locking groove Bd Receiving hole 4C Headrest base 10 Headrest moving mechanism (operating mechanism)
11B Rear surface portion 11D Bottom surface portion 11S Side surface portion 11U Upper surface portion 11R Rib 11H Long hole H0 Lower end portion H1 First stopper groove H2 Second stopper groove H3 Upper end portion 12 Link member 12A Connection shaft 12B Connection shaft 13 Arm member 13A Connection shaft 14 Hook 14A Connection shaft 14B Upper jaw portion 14C Lower jaw portion 14D Locking groove 14S Torsion spring 15 Operation member 15A Operation arm portion 15B Connection shaft 15C Engagement arm portion 15S Torsion spring 16 Tension spring 17 Lever member 17A Connection shaft 17B Receiving portion 17S Torsion spring 20 Pressure receiving mechanism 21 Formed wire 22 Pressure receiving plate 22A First arm 22B Second arm Bs Torsion spring Cr clip 30 Switching mechanism 31 Operation arm (moving member)
31C Locking claw 31S Torsion spring 32 Pendulum 32B Stopper piece 32C Weight 32S Torsion spring 40 Operation cable (cable)
41 Inner cable 41P Engagement protrusion 42 Outer cable 42S Long hole 42H Head 42D Guide part 50 Push rod

Claims (4)

A headrest actuating device that operates so that the headrest can be moved close to the seated person's head when a rear collision of the vehicle is detected,
A pressure receiving mechanism that detects the occurrence of a rear collision of the vehicle as a mechanical operation movement amount that is pushed and moved by the back of the seated occupant by the spring is provided inside the seat back, and is detected by the pressure receiving mechanism. The mechanical operation movement amount is transmitted to an operation mechanism that moves the headrest through a pulling operation of a cable connected to the pressure receiving mechanism, and the headrest is operated.
The cable connected to the pressure receiving mechanism is connected to the pressure receiving mechanism according to a mechanical operation movement detected by the pressure receiving mechanism by connecting to the pressure receiving mechanism and to a fixed body that is not linked to the pressure receiving mechanism. Is operated to move relative to the connection point with the fixed body, and the towing operation is performed.
The connection structure of at least one of the connection points is in a state in which the fixed state due to the connection does not function before the occurrence of a rear-end collision, and the mechanical operation movement amount is detected by the pressure receiving mechanism. However, the relative movement between the two connecting points is not performed, but when a rear collision of the vehicle occurs, the switching mechanism that detects and operates the rear collision switches the fixed state to the functioning state. A headrest actuating device characterized in that a relative movement between connecting points is performed. The headrest actuating device according to claim 1,
The pressure receiving mechanism is configured such that a pressure receiving plate provided on the skeleton of the seat back so as to be swingable in the front-rear direction receives a backrest load of a seated person and is pushed rearward to detect a mechanical operation movement amount. The pressure receiving plate is connected to the skeleton of the seat back via a four-bar linkage mechanism, and is fixed to the cable by the link movement of the four-bar linkage mechanism as it moves rearward. A headrest actuating device, characterized in that the headrest actuating device moves in a direction away from a connection point with the body. The headrest actuating device according to claim 1 or 2,
The cable has a double structure in which a wire-like inner cable is inserted inside a tubular outer cable, and an end portion of the outer cable is connected to the pressure receiving mechanism and fixed. The end portion of the inner cable drawn from the portion is connected and fixed to a moving member that is connected to the fixed body so as to be relatively movable, and relative movement of the moving member is allowed before the occurrence of a rear collision. As a state, the end of the inner cable follows the movement of the end of the outer cable, and the cable is not pulled. However, when the rear collision of the vehicle occurs, the switching mechanism causes the relative movement of the moving member. The end of the outer cable is moved relative to the end of the inner cable held in place by restricting the Headrest actuating device, characterized in that the state is performed. The headrest actuating device according to claim 3,
The headrest actuating device according to claim 1, wherein the moving member is urged by an urging member in a moving direction that separates the end portion of the inner cable from the end portion of the outer cable.

Images