JP2006082773A - Seat for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seat for a vehicle capable of quickly and surely operating a headrest at the time of a collision. <P>SOLUTION: This seat is provided with a headrest driving mechanism for operating the headrest, a pressure receiving member and a speed increasing unit 79 for driving the pressure receiving member in a direction for pulling a wire 44 by increasing the speed of the movement of the pressure receiving member. The speed increasing unit 79 has a base bracket 80 for connecting a one end 44a of the wire 44, a link mechanism 83 constituted by rotatably connecting a pair of arms 81 and 82, a roller 97 rotatably provided at an end part of the arm 82, a guide hole 100 for guiding moving of the roller 97, and an extension part 82a of the arm 82 functioning as a wire swing preventing means. The extension part 82a of the arm 82 suppresses separation of the wire 44 wound on the roller 97 from the roller 97. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle seat having a headrest.

In order to restrain an occupant's head at the time of a rear-end collision of a vehicle, a movable headrest device that moves the headrest forward at the time of a collision has been proposed. For example, there is a headrest device in which a pressure receiving plate is provided at a lower portion of a bracket that supports a headrest stage, and the bracket rotates in the front-rear direction around an axis positioned between the headrest and the pressure receiving plate. Are known. In this type of headrest device, the headrest moves forward when the occupant is pressed against the seat back by a collision and the pressure receiving plate is pushed backward. (See Patent Document 1 below)
Since the headrest device described in Patent Document 1 has a small amount of forward movement of the headrest relative to the amount of movement of the pressure receiving plate, it is difficult to constrain the head at an early stage, and the failure reduction effect is small. If the center of rotation is set downward, the operating speed of the headrest increases, and the head can be restrained early. However, the headrest step is greatly increased backward due to the load input when restraining the head. Since it will bend, the obstacle reduction effect will fall. If the rigidity of the stage is increased in order to reduce the deflection of the stage, there arises a problem that the weight of the stage increases.

There is also a headrest device that increases the ratio (link ratio) of the distance from the center of rotation of the headrest to the headrest and the distance from the center of rotation of the headrest to the pressure receiving plate by arranging the pressure receiving plate on the upper part of the seat back. Proposed. (See Patent Document 2 below)
JP-A-11-268565 JP 2001-58533 A

  In Patent Document 1, since the headrest and the pressure receiving plate move like a seesaw in directions opposite to each other with the axis between the headrest and the pressure receiving plate as a rotation center, the components are large and heavy. Tend to be. In addition, it takes time to assemble the seat back, and in the case of a power seat, it is necessary to dispose a movable part such as a pressure receiving plate so as not to interfere with the motor and power seat mechanism parts. Bad attachment.

  Even if the pressure receiving plate is disposed above as described in Patent Document 2, it is insufficient for early restraining of the head. In addition, when the pressure receiving plate is arranged on the upper part of the seat back, it is necessary to arrange the pressure receiving plate on the rear side in the thickness direction of the seat back as much as possible in order to prevent the pressure receiving plate from causing a foreign object feeling. is there. In that case, there arises a problem that the operation start time is delayed.

  Further, as in Patent Document 2, when the pressure receiving plate is provided at a relatively upper portion of the seat back and the pressure receiving plate is pushed by the back of the occupant, the pressure receiving plate is disposed at the lower portion of the seat back. The load input to the pressure receiving plate is smaller than that of the existing structure. Moreover, there is a problem that the start of operation is further delayed because the seat back frame itself bends backward.

  In order to solve these problems, the present inventors accommodate a speed increasing unit that speeds up the movement of the pressure receiving member inside the seat back, and outputs the output of the speed increasing unit via a wire to a headrest driving mechanism. A vehicle seat having a structure to be transmitted to the vehicle was considered. This speed increasing unit requires a roller wound around the wire in order to change the direction of the wire.

  However, when using a speed increasing unit and a wire, the movement of the wire when the headrest is activated causes the wire to move away from the roller, causing the wire to be detached from the roller, or the wire to be caught at a place other than the roller. There is a concern that the operation of the headrest may be hindered.

  Accordingly, an object of the present invention is to provide a vehicle seat capable of operating a headrest quickly and reliably at the time of a collision.

  The vehicle seat according to the present invention includes a seat back having a seat back frame, a headrest provided at an upper portion of the seat back, and an upper portion of the seat back frame that is movable in the vertical direction and tiltable in the front-rear direction. A support bracket for inserting the stage, a pressure receiving member that is provided on the seat back and moves rearward when pushed by an occupant, a wire that has one end and the other end and is disposed on the seat back, and the wire One end of the wire is connected, and when the pressure receiving member moves rearward, the speed increasing unit that accelerates the movement of the pressure receiving member to drive the wire in a pulling direction is connected to the other end of the wire, A headrest drive mechanism that tilts the support bracket to the front side while moving the support bracket upward when pulled.

  The speed increasing unit is a link mechanism that is provided on the seat back frame and to which one end of the wire is connected, and a link mechanism that connects the first arm and the second arm to each other so as to be rotatable. A link mechanism in which an end portion of the first arm is rotatably supported by the base bracket, and a connection portion between the first arm and the second arm projects toward the pressure receiving member; and the second arm A roller that is rotatably provided at an end of the wire and on which the wire is wound, and a connection portion between the first arm and the second arm is pushed rearward by the pressure receiving member. A guide means for guiding the movement of the roller so as to increase an angle formed; and a wire steadying means for suppressing the wire wound around the roller from being separated from the roller. It is.

  In a preferred embodiment of the present invention, a guide roller is provided at an end of the first arm, and the wire steadying means for suppressing the wire contacting the guide roller from separating from the guide roller on the first arm. Is provided.

  In one aspect of the present invention, a groove portion into which the wire enters is formed on an outer peripheral portion of the roller, and the wire steadying means extends a part of the second arm to a position facing the groove portion. is there.

  As another example of the wire steadying means, a concave portion into which the wire enters is formed in a part of the second arm. The wire steadying means may be a resin clip fitted to the outer peripheral portion of the roller so as to surround the wire.

  The wire steadying means may be a plastic working part formed by projecting a part of the base bracket toward the roller. The wire steadying means may be a tension member such as a spring that applies tension from the side of the wire so as to remove the slack of the wire wound around the roller. Moreover, you may use combining these several wire steadying means.

  According to the present invention, when the pressure receiving member moves rearward due to a collision, the movement of the pressure receiving member is accelerated by the speed increasing unit and transmitted to the headrest tilting mechanism via the wire, so that there is no operation delay. The head of the occupant can be restrained promptly. Further, it is possible to prevent the wire connecting the speed increasing unit and the headrest tilting mechanism from being detached from the roller of the speed increasing unit, and the headrest can be operated reliably.

A first embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 shows a vehicle seat 10. The vehicle seat 10 includes a seat portion 11, a seat back 12, and a headrest 13. The headrest 13 has a headrest main body 14 provided on the upper portion of the seat back 12 and a pair of left and right stages 15 extending below the headrest main body 14.

  2 and 3 show the interior of the seat back 12. The seat back 12 includes a seat back frame 20, a spring assembly 21, a pad member 22 (shown by a two-dot chain line in FIG. 3) arranged to cover the spring assembly 21, and a cover member that covers the outer surface of the pad member 22. 23 (shown in FIG. 1).

  The seat back frame 20 includes a pair of left and right side frame members 30 and 31, an upper frame member 32 positioned on the upper side, a lower frame member 33 positioned on the lower side, and the like. The side frame members 30 and 31 and the lower frame member 33 are formed into a predetermined shape by pressing a metal plate. The upper frame member 32 is made of a pipe having a circular cross section, for example, and both ends thereof are welded to the upper portions of the side frame members 30 and 31. Both ends of the lower frame member 33 are welded to lower portions of the side frame members 30 and 31.

  An example of the spring assembly 21 includes a flat spring 35 and a plurality of tension springs 36. The flat spring 35 is constituted by a plurality of vertical wires 37 extending in the vertical direction and horizontal wires 38 extending in the horizontal direction. Both side portions of the flat spring 35 are supported on the side frame members 30 and 31 by a tension spring 36.

  As shown in FIG. 2, two systems of cables 41 and 42 are arranged inside the seat back 12. FIG. 3 shows one cable 41 as a representative. Each of these cables 41, 42 has an outer tube 43 and a wire 44 inserted into the outer tube 43. The wire 44 is an example of a rope body, and is configured by twisting a plurality of strands.

  The intermediate portions in the longitudinal direction of the cables 41 and 42 are supported by, for example, the upper frame member 32 by a retainer 45 (shown in FIG. 3). As shown in FIGS. 2 and 3, the outer tube 43 has one end 43a and the other end 43b. The wire 44 also has one end 44a and the other end 44b.

  As shown in FIGS. 2 and 3, long hole brackets 51 each having a guide hole 50 are provided at both ends of the upper frame member 32 of the seat back frame 20. The guide hole 50 extends obliquely in the vertical direction so that one end 50a thereof is located in front of and lower than the other end 50b. A subframe 55 is provided between the pair of long hole brackets 51.

  The subframe 55 includes a horizontal portion 56 extending in the horizontal direction and a pair of arm portions 57 formed at both ends of the horizontal portion 56. The arm portion 57 extends obliquely downward and forward from both ends of the horizontal portion 56. A slide member (for example, a slide pin) 58 is provided at the end of each arm portion 57. The slide member 58 is inserted into the guide hole 50 of the long hole bracket 51 and comes into contact with the upper side portion 50c of the guide hole 50 at a contact C2 (shown in FIG. 4). The slide member 58 can move in the vertical direction (longitudinal direction of the guide hole) along one end 50 a and the other end 50 b of the guide hole 50 along the guide hole 50.

  The lower portions of the pair of left and right support brackets 60 are fixed to the horizontal portion 56 of the subframe 55. The stage 15 of the headrest 13 is inserted into each support bracket 60. The support bracket 60 has a cylindrical shape, and a grommet 61 is provided at the upper end. A sliding guide bracket 65 is provided on the upper frame member 32. The back surface 60 a of the intermediate portion in the vertical direction of the support bracket 60 is pressed toward the upper frame member 32 by the sliding guide bracket 65. The sliding guide bracket 65 is provided with a sliding guide member 66 made of synthetic resin at a portion in contact with the support bracket 60.

  The support bracket 60 can smoothly slide in the vertical direction with respect to the upper frame member 32 by the sliding guide member 66. The back surface 60a of the intermediate portion in the vertical direction of the support bracket 60 is supported by the sliding guide bracket 65 so as to contact the upper frame member 32 at the contact C1 (shown in FIG. 4). In addition, the support bracket 60 has a sliding guide bracket 65 and an upper frame member so that the support bracket 60 can be inclined in a range of a certain angle θ1 (shown in FIG. 3) in the front-rear direction with the contact C1 with the upper frame member 32 as a fulcrum. 32 and is supported so as to be tiltable.

  The long hole bracket 51, the subframe 55, the slide member 58, the support bracket 60, the sliding guide bracket 65, and the like constitute a headrest driving mechanism 67 for supporting the headrest 13 so as to be tiltable in the front-rear direction. ing.

  In the headrest drive mechanism 67, the headrest body 14 and the support bracket 60 move upward when the slide member 58 moves obliquely upward and backward along the guide hole 50 (in the direction indicated by the arrow A in FIGS. 3 and 4). However, the positions of the contact points C1 and C2, the length of the arm portion 57 of the sub-frame 55, the angle θ2 (shown in FIG. 3) formed by the arm portion 57 and the support bracket 60, etc. are set so as to incline forward. Yes.

  The headrest driving mechanism 67 is for operating the headrest body 14 when the pressure receiving member 70 described below moves rearward. That is, the headrest driving mechanism 67 is configured such that when the pressure receiving member 70 moves rearward, the headrest main body 14 moves in accordance with the sliding member 58 moving obliquely upward from the one end 50a toward the other end 50b along the guide hole 50. It has a function of driving the sub-frame 55 so as to incline forward while moving upward.

  The long hole bracket 51 has an upper side portion 50 c that is a guide surface along the longitudinal direction of the guide hole 50. The upper side portion 50c extends obliquely rearward and upward from one end 50a of the guide hole 50 toward the other end 50b. The wire 44 connected to the slide member 58 extends obliquely toward the upper side 50c side at an angle with respect to the upper side 50c of the guide hole 50. For this reason, when the slide member 58 moves upward along the guide hole 50, the slide member 58 contacts at the contact C2.

  The stage 15 of the headrest 13 is inserted into the support bracket 60 from the hole of the grommet 61. Each stage 15 is movable in the vertical direction with respect to the support bracket 60. The stage 15 is fixed to the support bracket 60 by a lock mechanism (not shown) in a state where the headrest body 14 is adjusted to a desired height.

  A pressure receiving member 70 is provided inside the seat back 12 so as to be positioned below the spring assembly 21, that is, behind the waist of the occupant (seater). The pressure receiving member 70 is attached to the spring assembly 21. When the spring assembly 21 is pushed by the occupant and bent backward, the pressure receiving member 70 can move together with the spring assembly 21 from the front side position toward the rear side position. A convex portion 71 protruding rearward is formed on a part of the pressure receiving member 70.

  A speed increasing unit 79 is provided at a position facing the rear surface of the pressure receiving member 70. The speed increasing unit 79 includes a base bracket 80 fixed to the lower frame member 33, and a first arm 81 and a second arm 82 provided on the base bracket 80. The speed increasing unit 79 has a vertical orientation in which the first arm 81 is located on the upper side and the second arm 82 is located on the lower side, that is, the longitudinal direction of the base bracket 80 is the vertical direction. Is arranged on the lower frame member 33 in a posture along

  As shown in FIGS. 3 and 5, one end 43 a of each outer tube 43 of the pair of cables 41 and 42 is connected to the cable support portion 85 of the base bracket 80. One end 44 a of each wire 44 of the cables 41 and 42 is connected to the wire support portion 86 of the base bracket 80.

  One end (upper end) of the first arm 81 is rotatably supported by the base bracket 80 by a first pin 90. The first pin 90 is an example of a first shaft. The base bracket 80 is provided with a guide roller 91 that can rotate around the first pin 90.

  The first arm 81 and the second arm 82 are rotatably connected to each other by a second pin 92 so as to form a lateral V shape when viewed from the side. In other words, the first arm 81 and the second arm 82 constitute a <shaped link mechanism 83, and the connecting portion of the first arm 81 and the second arm 82 projects toward the pressure receiving member 70. . The angle θ3 formed by the first arm 81 and the second arm 82 is preferably 90 ° or more (obtuse angle). The second pin 92 is an example of a second shaft.

  A roller 95 is provided at a connection portion between the first arm 81 and the second arm 82. The roller 95 is an example of a contact member. The roller 95 is rotatable around the second pin 92. The roller 95 is disposed so as to face the convex portion 71 projecting on the rear surface of the pressure receiving member 70, and when the pressure receiving member 70 moves rearward (in the direction indicated by the arrow B in FIGS. 3 and 5), the convex portion 71. Is in contact with the roller 95.

  The other end (lower end) of the second arm 82 is provided with a third pin 96 and a roller 97 that is rotatable about the third pin 96. The third pin 96 is an example of a third shaft. The third pin 96 is inserted into the guide hole 100 formed in the base bracket 80 and can move in the longitudinal direction of the guide hole 100 along the guide hole 100.

  The third pin 96 and the guide hole 100 constitute guide means. The guide means guides the movement of the roller 97 so that the angle θ3 formed by the first and second arms 81 and 82 increases when the roller 95 is pushed rearward by the pressure receiving member 70.

  When the roller 95 is pushed in the direction of arrow B in FIG. 5 by the pressure receiving member 70, the angle θ3 formed by the first arm 81 and the second arm 82 increases. Here, since the first pin 90 is supported by the base bracket 80, the third pin 96 moves from one end (upper end) 100a of the guide hole 100 toward the other end (lower end) 100b. For this reason, the distance from the 1st pin 90 to the 3rd pin 96 becomes large gradually. That is, the roller 97 moves downward along the guide hole 100.

  As shown in FIG. 5, the guide hole 100 has a first portion 101 located on the side close to the first pin 90 and a second portion 102 located on the side far from the first pin 90. Yes. The first portion 101 extends obliquely downward and rearward at an angle θ4 with respect to an extension line L1 connecting the first pin 90 and the third pin 96. The second portion 102 is bent to the opposite side (obliquely lower front) to the first portion 101 with respect to the extension line L1.

  For this reason, when the roller 97 moves along the guide hole 100 from one end 100 a of the guide hole 100 toward the other end 100 b, the third pin 96 can easily move along the first portion 101. When the third pin 96 moves along the second portion 102, the moving speed of the roller 97 becomes higher than when the first portion 101 moves.

  As shown in FIGS. 5 and 6, a part 44 c of each wire 44 of the pair of cables 41 and 42 is in contact with a part of the guide roller 91. On the lower side of the roller 97, a portion 44d on the other end side of each wire 44 is wound about half a circumference. In other words, the portion 44 d on the other end side of the wire 44 is fixed to the wire support portion 86 of the base bracket 80 in a state where the direction is changed by approximately 180 ° (U-turn) by the roller 97. .

  For this reason, when the roller 97 moves along the guide hole 100 from the one end 100a of the guide hole 100 toward the other end 100b, the roller 97 moves downward like a moving pulley, so that each wire 44 is connected to the roller 97. It is drawn by the length corresponding to the distance twice as much as the movement amount. In other words, when the pressure receiving member 70 moves rearward (in the direction of arrow B), the movement of the pressure receiving member 70 is increased by the speed increasing unit 79, and the wire 44 is pulled quickly.

  As shown in FIGS. 7 to 9, a groove portion 91 a is formed along the circumferential direction of the guide roller 91 on the outer peripheral portion of the guide roller 91 attached to the first arm 81. When a part of the wire 44 in contact with the guide roller 91 enters the groove portion 91a, the wire 44 is prevented from moving in the direction of the axis X (shown in FIG. 9) of the guide roller 91.

  An extension portion 81 a is formed on the first arm 81. The extending portion 81a functions as a wire steadying means as referred to in the invention. As shown in FIGS. 7 to 9, the tip 81 b of the extending portion 81 a extends to a position near the guide roller 91.

  The extension part 81a faces the groove part 91a with the wire 44 interposed therebetween, whereby the wire 44 contained in the groove part 91a is suppressed from floating in the radial direction of the guide roller 91. The distal end 81 b of the extending portion 81 a has a curved shape so that a smooth curved surface can face the wire 44.

  As shown in FIGS. 5 and 6, a groove 97 a along the circumferential direction of the roller 97 is formed on the outer periphery of the roller 97. When a part of the wire 44 in contact with the roller 97 enters the groove 97 a, the wire 44 is prevented from moving in the axial direction of the roller 97.

  An extension 82 a is formed on the second arm 82. This extending portion 82a also functions as a wire steadying means as referred to in the invention. As shown in FIG. 5, the leading end 82 b of the extending portion 82 a extends to a position near the roller 97. The extension portion 82 a faces the groove portion 97 a with the wire 44 interposed therebetween, whereby the wire 44 contained in the groove portion 97 a is suppressed from floating in the radial direction of the roller 97.

  The other end 44 b (shown in FIG. 3) of each wire 44 of the pair of cables 41 and 42 is connected to each slide member 58 of the headrest drive mechanism 67. Therefore, when each wire 44 is pulled in the direction indicated by the arrow D in FIG. 3 by the speed increasing unit 79, each slide member 58 of the headrest drive mechanism 67 moves in the direction indicated by the arrow A.

Next, the operation of the vehicle seat 10 having the above configuration will be described.
When the occupant is pressed against the seat back 12 at the time of the collision, the pressure receiving member 70 is pushed backward by a load input to the seat back 12 from the vicinity of the occupant's waist. As a result, the pressure receiving member 70 pushes the roller 95 of the speed increasing unit 79, so that the angle θ3 (shown in FIG. 5) formed by the first arm 81 and the second arm 82 increases. 82 moves.

  At this time, the third pin 96 moves downward along the guide hole 100, so that the roller 97 moves downward. Since each wire 44 of the pair of cables 41 and 42 is wound around the roller 97 in a U shape about half a circumference, the wire 44 is moved at a speed about twice the moving speed of the roller 97 according to the principle of a so-called moving pulley. It is drawn in the direction indicated by arrow E in FIG. Therefore, each slide member 58 of the headrest drive mechanism 67 moves in the direction indicated by the arrow A in FIG.

  Since the first portion 101 of the guide hole 100 is inclined rearward at an angle θ4 (shown in FIG. 5) with respect to the extension line L1 of the first and third pins 90 and 96, the roller 95 is an arrow. When pushed in the B direction, initially, the third pin 96 moves downward along the first portion 101 while moving slightly backward. For this reason, the wire 44 can be easily pulled out from the outer tube 43.

  Thereafter, since the third pin 96 moves along the second portion 102, the drawing speed of the wire 44 increases. Such a guide hole 100 allows the wire 44 to be pulled out by changing the inclination angle θ4 of the first portion 101 or changing the angle formed by the second portion 102 with respect to the first portion 101. The speed can be adjusted.

  The first arm 81 and the second arm 82 constituting the link mechanism 83 are formed with extending portions 81a and 82a that function as wire steadying means, respectively. For this reason, it is suppressed that the wire 44 floats from the outer peripheral surface of the rollers 91 and 97. In addition, the wire 44 is prevented from moving in the axial direction of the rollers 91 and 97 by the grooves 91 a and 97 a formed in the rollers 91 and 97.

  For this reason, even if the wire 44 is moved at a high speed by the speed increasing unit 79 at the time of a collision, the wire 44 is detached from the guide roller 91 or the wire 44 is loosened and interferes with members other than the rollers 91 and 97. This can be avoided and the headrest 13 can be operated reliably.

  As described above, the wires 44 of the cables 41 and 42 are simultaneously pulled by the speed increasing unit 79 at the time of the collision, whereby the slide members 58 of the pair of left and right headrest drive mechanisms 67 are respectively along the guide holes 50. Then, it moves obliquely upward and rearward (in the direction indicated by arrow A in FIGS. 3 and 4).

  When the slide member 58 moves along the guide hole 50 from the one end 50a toward the other end 50b, the arm portion 57 of the subframe 55 moves upward and backward. Along with this, the support bracket 60 moves up so as to fall forward with the contact C1 as a fulcrum. Since the contact C1 itself remains in the same position without moving forward, the headrest main body 14 moves forward and upward along a locus shown by the arrow M1 in FIG. 4 without accelerating restraint under the occupant's neck. Thus, the head is quickly restrained by the headrest body 14 before the neck is restrained.

  A horizontal rear load Fa (shown in FIG. 3) is input to the headrest body 14 by the head contacting the headrest body 14 after the headrest 13 is activated or during the operation. In order to support the rear load Fa, a front load Fb is generated at the support bracket 60 at the first contact C1, and a rear load Fc is generated at the slide member 58 at the second contact C2. Therefore, as the reaction force, the rear load Fb ′ is applied to the upper frame member 32 at the first contact C1, and the front load Fc ′ is applied to the long hole bracket 51 at the second contact C2.

  The rear load Fb ′ input to the upper frame member 32 is supported by the upper frame member 32. The forward load Fc ′ input to the long hole bracket 51 is supported by the side frame members 31 and 32. In this way, by receiving the rear load Fa of the headrest body 14 at the upper and lower two contact points C1, C2 (shown in FIG. 4), the return of the headrest body 14 is suppressed. For this reason, the head can be surely restrained, which is effective in reducing the whiplash obstacle value.

  In the seat back 12 of the present embodiment, the backward movement of the pressure receiving member 70 is transmitted from the speed increasing unit 79 to the headrest drive mechanism 67 via the wires 44 of the pair of cables 41 and 42. Even if the distance from the speed unit 79 to the headrest driving mechanism 67 is large, the movement of the pressure receiving member 70 can be quickly transmitted to the headrest driving mechanism 67 by the wire 44.

  For this reason, even if the distance from the speed increasing unit 79 to the headrest drive mechanism 67 is relatively large, the entire apparatus including the pressure receiving member 70 and the headrest drive mechanism 67 can be configured to be lightweight. Further, it is easy to assemble the speed increasing unit 79 and the headrest drive mechanism 67 inside the seat back 12.

  Moreover, the vehicle seat 10 according to the present embodiment is configured to increase the moving speed of the pressure receiving member 70 at the time of the collision by the speed increasing unit 79 and operate the headrest driving mechanism 67 via the wire 44. Excellent and no delay in operation. Since the speed increasing unit 79 is configured independently of the pressure receiving member 70, the assembling property to the seat back frame 20 is good.

  FIG. 10 shows a speed increasing unit 79A according to the second embodiment of the present invention. This speed increasing unit 79A directly connects the wire 44 drawn from one end 43a of each outer tube 43 of the cables 41 and 42 to the roller 97 without using the guide roller 91 used in the first embodiment. It is wrapped. Then, the direction of the wire 44 is reversed by 180 ° (U-turn) by the roller 97, and each wire 44 is connected to the wire support portion of the base bracket 80. Since other configurations, operations, and effects are the same as those of the speed increasing unit 79 of the first embodiment, the same reference numerals as those of the first embodiment are used and description thereof is omitted.

  11 to 13 show an arm 81 and a roller 91 of a speed increasing unit according to a third embodiment of the present invention. As shown in FIG. 13, no groove is formed on the outer periphery of the roller 91 of this embodiment. Instead, a concave portion 200 is formed in the extending portion 81a formed in the arm 81 as a wire steadying means by plastic working such as pressing.

  When a part of the wire 44 enters the recess 200, the wire 44 is held at a predetermined position and the wire 44 is guided. The extension part 81 a having such a recess 200 prevents the wire 44 in contact with the roller 91 from moving in the axis X direction and the radial direction of the roller 91.

  In this embodiment, since it is not necessary to form a groove in the roller 91 as shown in FIG. 13, the shape of the roller 91 is not complicated and the cost can be reduced. Other configurations and operations are the same as those of the speed increasing unit 79 of the first embodiment. 11 to 13 may be applied to the second arm 82 described in the first embodiment.

  FIG. 14 shows an arm 81 and a roller 91 of a speed increasing unit according to the fourth embodiment of the present invention. In this embodiment, a recess 200 is formed at the end of the arm 81 by plastic working such as pressing. When a part of the wire 44 enters the recess 200, the wire 44 in contact with the roller 91 is suppressed from moving in the axial direction and the radial direction of the roller 91. According to this configuration, the shape of the arm 81 can be further simplified. Such a wire steadying means using the recess 200 may be employed in the second arm 82 described in the first embodiment.

  15 to 17 show a fifth embodiment of the present invention. The wire steadying means of this embodiment is a resin clip 220 fitted to the outer periphery of the roller 97. The resin clip 220 is attached to the roller 97 by elastically deforming itself. The resin clip 220 surrounds a part of the wire 44 that contacts the roller 97.

  A groove 221 into which a part of the wire 44 enters is formed on the inner surface side of the resin clip 220. The groove 221 prevents the wire 44 from moving in the axial direction and the radial direction of the roller 97. Since the other configuration is the same as that of the first embodiment, the same reference numerals are assigned to the same parts as those of the first embodiment, and the description thereof is omitted.

  FIG. 18 shows a part of the speed increasing unit according to the sixth embodiment of the present invention. The wire steadying means of this embodiment is a plastic working portion 250 formed on the base bracket 80. The plastic working portion 250 is formed by projecting a part of the base bracket 80 toward the roller 97 by drawing or the like. A concave portion 251 into which a part of the wire 44 enters is formed on the side facing the wire 44 of the plastic working portion 250.

  The plastic working part 250 having such a recess 251 suppresses the movement of the wire 44 in the axial direction and the radial direction of the roller 97. Since the other configuration is the same as that of the first embodiment, the same reference numerals are assigned to the same parts as those of the first embodiment, and the description thereof is omitted.

  FIG. 19 shows a seventh embodiment of the present invention. The wire steadying means of this embodiment is a tension member 260 such as a tension spring. The tension member 260 is provided in a state where a tension is applied between the wire 44 and the base bracket 80 in order to remove the slack of the wire 44 between the rollers 91 and 97.

  Tension is applied from the side of the wire 44 by the tension member 260, and the wire 44 is suppressed from moving in the radial direction of the rollers 91 and 97. For this reason, it is possible to prevent the wire 44 from being loosened and separated from the rollers 91 and 97. Since the other configuration is the same as that of the first embodiment, the same reference numerals are assigned to the same parts as those of the first embodiment, and the description thereof is omitted.

The perspective view of the vehicle seat which shows the 1st Embodiment of this invention. The perspective view which shows the inside of the seat back of the vehicle seat shown by FIG. The side view which shows the inside of the seat back of the vehicle seat shown by FIG. The side view of the headrest drive mechanism of the seat back shown in FIG. FIG. 4 is a side view of the speed increasing unit for the seat back shown in FIG. 3. FIG. 6 is a perspective view of the speed increasing unit shown in FIG. 5. FIG. 6 is a perspective view of a part of the speed increasing unit shown in FIG. 5. FIG. 6 is a side view of a part of the speed increasing unit shown in FIG. 5. Sectional drawing which follows the F9-F9 line | wire in FIG. The perspective view of the speed increasing unit which shows the 2nd Embodiment of this invention. The perspective view of a part of speed increasing unit which shows the 3rd Embodiment of this invention. FIG. 12 is a side view of a part of the speed increasing unit shown in FIG. 11. Sectional drawing which follows the F13-F13 line | wire in FIG. The perspective view of a part of speed increasing unit showing the 4th embodiment of the present invention. The side view of a part of the speed increasing unit showing the fifth embodiment of the present invention. FIG. 16 is an exploded perspective view of a part of the speed increasing unit shown in FIG. 15. FIG. 16 is a partial cross-sectional view of the speed increasing unit shown in FIG. 15. The side view which shows the speed increasing unit which shows the 6th Embodiment of this invention in a partial cross section. The side view of the speed increasing unit which shows the 7th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Vehicle seat 12 ... Seat back 13 ... Headrest 20 ... Seat back frame 44 ... Wire 60 ... Support bracket 67 ... Headrest drive mechanism 70 ... Pressure receiving member 79 ... Speed increasing unit 80 ... Base bracket 81 ... First arm 82 ... Second arm 82a ... extension portion (wire steadying means)
83 ... Link mechanism 91 ... Guide roller 97 ... Roller 100 ... Guide hole (guide means)
200 ... concave portion (wire steadying means)
220 ... Resin clip (wire steadying means)
250 ... Plastic working part (wire steadying means)
260 ... tension member (wire steadying means)

Claims (7)

A seat back having a seat back frame;
A headrest provided on the upper portion of the seat back;
A support bracket which is provided on the upper part of the seat back frame so as to be movable in the vertical direction and tiltable in the front-rear direction, and for inserting the stage of the headrest;
A pressure receiving member that is provided in the seat back and moves rearward when pressed by an occupant;
A wire having one end and the other end disposed on the seat back;
A speed increasing unit that is connected to one end of the wire and that drives the pressure receiving member in a direction to pull the wire by increasing the movement of the pressure receiving member when the pressure receiving member moves rearward;
A headrest drive mechanism that is connected to the other end of the wire and tilts forward while moving the support bracket upward when the wire is pulled;
The speed increasing unit is:
A base bracket provided on the seat back frame to which one end of the wire is connected;
The first arm and the second arm are rotatably connected to each other, and the end of the first arm is rotatably supported by the base bracket, and the first arm and the second arm A link mechanism protruding in the direction of the pressure receiving member,
A roller that is rotatably provided at an end of the second arm and winds the wire;
Guide means for guiding the movement of the roller so that an angle formed by the first and second arms is increased when a connecting portion between the first arm and the second arm is pushed backward by the pressure receiving member; ,
Wire steadying means for preventing the wire wound around the roller from separating from the roller;
A vehicle seat characterized by comprising:   A guide roller is provided at an end portion of the first arm, and a wire steadying means is provided on the first arm to suppress the wire contacting the guide roller from being separated from the guide roller. The vehicle seat according to claim 1, wherein: A groove portion into which the wire enters is formed on the outer peripheral portion of the roller,
3. The vehicle seat according to claim 1, wherein the wire steadying means extends a part of the second arm to a position facing the groove. 4.   The vehicle seat according to claim 3, wherein the wire steadying means is formed with a recess into which the wire enters a part of the second arm.   The vehicle seat according to claim 1, wherein the wire steadying means is a resin clip fitted to an outer peripheral portion of the roller so as to surround the wire.   The vehicle seat according to claim 1, wherein the wire steadying means is a plastic processing portion formed by projecting a part of the base bracket toward the roller.   The vehicle seat according to claim 1, wherein the wire steadying means is a tension member that applies tension from a side of the wire so as to remove the slack of the wire wound around the roller.

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