Headrest and vehicle seat

Abstract

To provide a headrest which can prevent whiplash of an occupant and contribute to miniaturization of a headrest body.SOLUTION: In a headrest 20, a headrest body 26 is supported on a headrest stay 22 connected to a top end part of a seat back 14. In a headrest body 26, a plate-like member 30 is arranged. The plate-like member 30 is formed in the plate shape and is arranged in the headrest body 26 in such a posture that the plate thickness direction is along the front-rear direction. When the vehicle is collided from its rear face, the plate-like member 30 is bent by being compressed in the direction orthogonal to the plate thickness direction by a compression part and a front surface of the headrest body 26 swells to the front side. Thereby, whiplash of an occupant can be prevented since the head of the occupant is supported by the headrest body 26 at an early stage. Also, since the plate-like member 30 is formed into the plate shape, the arrangement space of the plate-like member 30 in the headrest body 26 can be set to be thin in the front-rear direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a vehicle seat, and more particularly to a headrest for a vehicle seat. [Background technology]

[0002] Patent Document 1 below discloses a vehicle seat structure equipped with a so-called active headrest. This vehicle seat structure includes a rotation mechanism that rotates the headrest body forward around the lower end of the headrest body, a biasing means that biases the upper end of the headrest body to rotate forward, a locking means that locks the rotation of the headrest body against the biasing force of the biasing means, and a response means that releases the lock provided by the locking means when the rearward load of the occupant applied to the seat back exceeds a predetermined magnitude. In the event of a rear-end collision, the headrest body rotates forward to support the occupant's head, thereby preventing whiplash of the occupant. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-155558 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, in the third-row seats of so-called minivan-type vehicles and the second-row seats of light vehicles, the headrest body needs to be made smaller, so it can be difficult to accommodate the active headrest mechanism inside the headrest body.In particular, in so-called saddle-type headrests, the lower part of the headrest body is formed thin in the front-to-rear direction of the seat, making it difficult to secure space to accommodate the active headrest mechanism.

[0005] SUMMARY OF THE INVENTION In consideration of the above, an object of the present invention is to provide a headrest and a vehicle seat that can prevent whiplash of an occupant and that contributes to miniaturization of the headrest body. [Means for solving the problem]

[0006] The headrest of the first aspect comprises a headrest stay connected to the upper end of the seat back of a vehicle seat, a headrest main body supported by the headrest stay, a plate-shaped member that is disposed within the headrest main body with its thickness direction aligned with the front-to-rear direction of the headrest and is supported by the headrest stay, and that is compressed and bent in a direction perpendicular to the thickness direction, thereby causing the front surface of the headrest main body to bulge toward the front of the headrest, and a compression section that compresses the plate-shaped member in the perpendicular direction when the vehicle is involved in a rear-end collision.

[0007] In the headrest of the first aspect, a headrest main body is supported by a headrest stay connected to the upper end of the seat back of a vehicle seat. A plate-shaped member is disposed within the headrest main body. The plate-shaped member is formed in a plate shape and disposed within the headrest main body with its thickness direction aligned with the front-to-rear direction of the headrest. In the event of a rear-end collision of the vehicle, the plate-shaped member is compressed and bent by the compression portion in a direction perpendicular to the thickness direction, causing the front surface of the headrest main body to bulge forward of the headrest. This allows the occupant's head to be supported by the headrest main body early, thereby preventing whiplash of the occupant. Moreover, because the plate-shaped member is formed in the above-described plate shape, the arrangement space for the plate-shaped member within the headrest main body can be made thin in the front-to-rear direction of the headrest. This contributes to the miniaturization of the headrest main body.

[0008] In the headrest of the second aspect 2, in the first aspect, the plate-like member has a plurality of hinge portions aligned in the orthogonal direction, and is bent at the plurality of hinge portions by the compression.

[0009] In the headrest of the second aspect, when the vehicle is involved in a rear-end collision, the plate-shaped member is compressed by the compression portion in a direction perpendicular to the plate thickness direction, causing the plate-shaped member to bend at the multiple hinge portions. These multiple hinge portions make it easy to bend the plate-shaped member as designed.

[0010] The headrest of the third aspect is the headrest of the first or second aspect, wherein the headrest stays have left and right leg portions connected to the upper end of the seat back, left and right forward extension portions extending from the upper ends of the left and right legs toward the front of the headrest, and left and right downward extension portions extending from the front ends of the left and right forward extension portions toward the lower side of the headrest, and the headrest main body has an upper portion in which the left and right forward extension portions are embedded, and a lower portion extending from the front end of the upper portion toward the lower side of the headrest and in which the left and right downward extension portions are embedded, and the plate-like member is embedded in the lower portion and supported by the left and right downward extension portions.

[0011] In the headrest of the third aspect, the headrest stays and the headrest main body have the above-described configuration, i.e., a so-called saddle-type headrest configuration. In a saddle-type headrest, the lower part of the headrest main body is formed thin in the front-to-rear direction of the headrest, and the plate-like member embedded in this lower part is disposed within the lower part of the headrest main body with its plate thickness direction aligned with the front-to-rear direction of the headrest, making it easy to secure space for disposing the plate-like member within the lower part.

[0012] The headrest of the fourth aspect is any one of the first to third aspects, wherein the compression portion has a spring that compresses the plate-shaped member in the perpendicular direction by a spring force, a locking portion that restricts the compression of the plate-shaped member, and a release portion that releases the restriction when the vehicle is involved in a rear-end collision.

[0013] In the headrest of the fourth aspect, when the vehicle is involved in a rear-end collision, the release unit releases the locking unit. As a result, the plate-shaped member is compressed in a direction perpendicular to the plate thickness direction by the biasing force of the spring and bent. Because the plate-shaped member is bent by the biasing force of the spring, the configuration can be simplified compared to when the plate-shaped member is bent using, for example, the driving force of an actuator.

[0014] In the headrest of the fifth aspect, in the fourth aspect, the release portion is arranged within the seat back and has a pressure receiving portion that receives a load from an occupant in the event of a rear-end collision of the vehicle, and a load transmitting portion that transmits the load received by the pressure receiving portion to the locking portion, thereby releasing the restriction.

[0015] In the headrest of the fifth aspect, when the vehicle is involved in a rear-end collision, a pressure receiving portion disposed within the seat back receives a load from the occupant. The load received by the pressure receiving portion is transmitted to the locking portion by the load transmitting portion, and the locking portion is released from its restriction. In this way, the locking portion is released from its restriction by the load from the occupant, which simplifies the configuration compared to, for example, a case in which an actuator is activated to release the locking portion when a collision sensor detects a rear-end collision.

[0016] The headrest of the sixth aspect is any one of the first to fifth aspects, and is configured such that when the plate-like member is bent, multiple reinforcing ribs provided on at least one of the side and back surfaces of the plate-like member engage with each other.

[0017] In the headrest of the sixth aspect, when the plate-shaped member is bent, the reinforcing ribs provided on at least one of the side and back surfaces of the plate-shaped member engage with each other to provide rigidity, which allows the front surface of the headrest body, which bulges forward, to properly support the occupant's head.

[0018] A vehicle seat according to a seventh aspect includes a seat cushion, a seat back, and the headrest according to any one of the first to sixth aspects, in which the headrest stay is connected to an upper end of the seat back.

[0019] In the vehicle seat of the seventh aspect, the headrest stays of the headrest are connected to the upper end of the seat back. This headrest is one of the first to sixth aspects, and therefore the above-mentioned functions and effects can be obtained. [Effects of the Invention]

[0020] As described above, the headrest and vehicle seat according to the present invention can prevent whiplash of an occupant and contribute to miniaturization of the headrest body. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 2 is a side view showing the configuration of a main part of the headrest according to the embodiment. [Figure 2] FIG. 2 is a side view corresponding to FIG. 1, showing a state in which the plate-like member is bent. [Figure 3] FIG. 2 is a perspective view showing a configuration around a plate-shaped member in the headrest according to the embodiment. [Figure 4] FIG. 4 is a side view corresponding to FIG. 3, showing the plate-like member in a bent state. [Figure 5] 10 is a perspective view showing a configuration of the vicinity including a part of a load transmission portion of a release portion of a headrest according to an embodiment. FIG. [Figure 6] 10 is a side view showing the configuration of the periphery of a pressure receiving portion of a release portion of the headrest according to the embodiment. FIG. [Figure 7] 10 is a front view showing the configuration of the periphery of a pressure receiving portion of a release portion of the headrest according to the embodiment. FIG. [Figure 8] FIG. 10 is a plan view showing the configuration of a main part of a headrest according to a first modified example of the embodiment. [Figure 9] 9 is a plan view corresponding to FIG. 8, showing a state in which the plate-like member is bent. [Figure 10] FIG. 10 is a perspective view showing the configuration of a main part of a headrest according to a second modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] A vehicle seat 10 and a headrest 20 according to one embodiment of the present invention will be described below with reference to Figures 1 to 7. Note that in each figure, some reference numerals may be omitted to make the drawings easier to understand. Arrows FR, LH, and UP, which are appropriately depicted in each figure, indicate the front, left, and top of the vehicle seat 10 and the headrest 20, respectively. In the following description, when the front-rear, left-right, and top-bottom directions are simply used, they refer to directions relative to the vehicle seat 10 and the headrest 20.

[0023] As shown in FIG. 7, the vehicle seat 10 according to this embodiment includes a seat cushion on which a vehicle occupant sits and a seat back 14 against which the occupant leans. The lower end of the seat back 14 is connected to the rear end of the seat cushion 12 via a well-known reclining mechanism. As shown in FIG. 6, a pair of left and right headrest supports 16 (only the right headrest support 16 is shown in FIG. 6) is provided at the upper end of the seat back 14. The left and right headrest supports 16 are attached to a pair of left and right headrest support brackets 18 (only the right headrest support bracket 18 is shown in FIG. 6) fixed to the upper end of a frame 15 of the seat back 14. Headrests 20, which are components of the vehicle seat 10, are connected to the left and right headrest supports 16.

[0024] As shown in FIGS. 1 and 2, the headrest 20 according to this embodiment is a so-called saddle-shaped headrest and includes a headrest stay 22, a headrest main body 26, a plate-shaped member 30, and a compression portion 34. The headrest stay 22 is manufactured, for example, by bending a metal pipe. The headrest stay 22 includes a pair of left and right leg portions 22A connected to the left and right headrest supports 16, a pair of left and right front extension portions 22B extending forward from the upper ends of the left and right leg portions 22A, a pair of left and right lower extension portions 22C extending downward from the front ends of the left and right front extension portions 22B, and a horizontal extension portion 22D connecting the lower ends of the left and right lower extension portions 22C in the horizontal direction. Note that FIGS. 3 and 4 illustrate the front side of the headrest stay 22 and its surrounding structure, while FIG. 5 illustrates the rear side of the headrest and its surrounding structure. For convenience of explanation, the headrest stay 22 is shown in a cut state in FIGS. 3 to 5.

[0025] The headrest main body 26 is configured such that a headrest pad made of a foam such as urethane foam is covered with a headrest skin 28 made of a cloth material, leather, synthetic leather, or the like, and is supported by the headrest stays 22. The headrest main body 26 is configured with an upper portion 26A in which the left and right forward extension portions 22B of the headrest stays 22 are embedded, and a lower portion 26B that extends downward from the front end of the upper portion 26A and in which the left and right downward extension portions 22C are embedded, forming a substantially inverted L-shape when viewed from the left and right. The upper portion 26A is plate-shaped with its thickness direction extending up and down, and the lower portion 26B is plate-shaped with its thickness direction extending approximately in the front-to-rear direction.

[0026] The plate-like member 30 is manufactured, for example, by injection molding of resin, and is formed in a plate-like, i.e., thin, flat shape. This plate-like member 30 is disposed within the headrest main body 26 with its thickness oriented along the front-to-rear direction. More specifically, the plate-like member 30 is embedded within the lower portion 26B of the headrest main body 26, and disposed in front of the left and right downward extension portions 22C. A cylindrical shaft member 24, whose axis is directed in the left-to-right direction, is disposed above the plate-like member 30 at the upper ends of the left and right downward extension portions 22C. The shaft member 24 is fixed to the left and right downward extension portions 22C by, for example, welding.

[0027] An upper connecting portion 30A is formed at the upper end of the plate-shaped member 30 along the left-right direction. The upper connecting portion 30A protrudes upward from the upper end of the plate-shaped member 30 and has a C-shape that opens upward when viewed in the left-right direction. Both left and right ends of the shaft member are rotatably fitted inside the upper connecting portion 30A. This allows the upper end of the plate-shaped member 30 to be rotatably connected to the headrest stay 22 around the shaft member 24 (i.e., around an axis along the left-right direction).

[0028] A pair of left and right lower connecting portions 30B are formed on the lower portion of the plate-like member 30. The left and right lower connecting portions 30B protrude rearward from the lower portion of the plate-like member 30 and are C-shaped with an opening toward the rear when viewed in a generally vertical direction. The left and right lower extending portions 22C are fitted into the inside of the left and right lower connecting portions 30B. The left and right lower connecting portions 30B are slidable in a generally vertical direction along the left and right lower extending portions 22C. This allows the lower portion of the plate-like member 30 to be slidably connected to the headrest stay 22 in a generally vertical direction.

[0029] A plurality of (here, three) hinge portions 32 are formed in a vertically intermediate portion of the plate-shaped member 30 between the upper connecting portion 30A and the left and right lower connecting portions 30B, aligned approximately vertically. These hinge portions 32 are so-called integral hinges and extend in the horizontal direction. The plate-shaped member 30 having the plurality of hinge portions 32 formed thereon is bent at the plurality of hinge portions 32 when compressed in a direction perpendicular to the plate thickness direction (here, approximately vertically). Specifically, when an upward load acts on the lower portion of the plate-shaped member 30, the left and right lower connecting portions 30B slide upward relative to the left and right lower extension portions 22C, and the lower portion of the plate-shaped member 30 approaches the upper end portion of the plate-shaped member 30. At this time, as shown in FIGS. 2 and 4 , the plate-shaped member 30 bends at the plurality of hinge portions 32, causing the vertically intermediate portion of the plate-shaped member 30 to bulge forward in a substantially trapezoidal shape when viewed in the horizontal direction. As a result, the front surface of the headrest main body 26 bulges forward as shown by the two-dot chain line in Fig. 2. When the plate-shaped member 30 is bent at the multiple hinge portions 32, the tooth-shaped shapes of the multiple reinforcing ribs 33 (the reinforcing ribs 33 on the back surface are not shown) provided on the side and back surfaces of the plate-shaped member 30 are configured to engage with each other as shown in Figs. 2 and 4.

[0030] The compression portion 34 has a pair of left and right tension coil springs 36 attached to the left and right lower extension portions 22C of the headrest stay 22. The left and right tension coil springs 36 correspond to the "springs" in this invention and are arranged with the left and right lower extension portions 22C inserted therethrough. The upper ends of the left and right tension coil springs 36 are engaged with the shaft member 24, and the lower ends of the left and right tension coil springs 36 are engaged with the left and right lower connecting portions 30B. These tension coil springs 36 bias the lower portion of the plate-shaped member 30 upward. The lower portion of the plate-shaped member 30 is restricted from upward displacement by locking portions 38 (see FIGS. 3 and 4 ) included in the compression portion 34. In other words, the biasing force of the left and right tension coil springs 36 acts to compress the plate-shaped member 30 in a direction perpendicular to the plate thickness direction, but this compression is restricted by the locking portions 38.

[0031] As shown in FIGS. 3 and 4 , the locking portion 38 is, for example, composed of a locking piece 40 provided on the lower portion of the plate-shaped member 30 and a hook 42 fixed to the horizontal extension portion 22D of the headrest stay 22. The locking piece 40 extends rearward integrally from the lower portion 30C of the plate-shaped member 30. The locking piece 40 integrally includes a plate-shaped elastic portion 40A having a thickness direction generally in the vertical direction and a longitudinal direction generally in the front-rear direction, and a locking claw portion 40B extending downward from a central portion of the elastic portion 40A in the front-rear direction. The locking claw portion 40B is formed in a generally J-shape when viewed from the left and right. The hook 42 is manufactured, for example, by bending a metal plate and is fixed to a central portion of the horizontal extension portion 22D in the left and right direction by means of welding or the like. The hook 42 is formed in a generally inverted J-shape when viewed from the left and right, and protrudes upward from the horizontal extension portion 22D. The lower end of the locking claw 40B is hooked onto the upper end of the hook 42, thereby restricting upward displacement of the lower portion 30C of the plate-like member 30. When an upward load acts on the rear end of the elastic portion 40A, the elastic portion 40A elastically deforms upward, releasing the hooking of the lower end of the locking claw 40B onto the upper end of the hook 42. One end of a cable 48 is fastened to the rear end of the elastic portion 40A. The cable 48 constitutes a part of the load transmission portion 46, which is a component of the release portion 44 of the compression portion 34.

[0032] As shown in Fig. 5, the load transmission unit 46 includes, in addition to the cable 48, a base plate 50 attached to the upper ends of the left and right legs 22A of the headrest stay 22, a pulley 52 attached to the base plate 50, and a pair of left and right cables 54, one end of each of which is fastened to the pulley 52. The base plate 50 is formed, for example, from a metal plate and has a rectangular shape with its thickness extending vertically. The base plate 50 is disposed within the upper portion 26A of the headrest body 26. The upper ends of the left and right legs 22A penetrate the rear portion of the base plate 50, and the base plate 50 is fixed to the upper ends of the left and right legs 22A by means of welding or the like. A guide 51, through which the other end of the cable 48 passes, is fixed to the upper surface of the front portion of the base plate 50.

[0033] The pulley 52 is disposed on the upper surface of the rear portion of the base plate 50, between the upper ends of the left and right legs 22A. The pulley 52 is disk-shaped with its axis extending in the vertical direction, and is rotatably supported relative to the base plate 50. The other end of the cable 48 is fastened to the outer periphery of the pulley 52, and the other end of the cable 48 is wound around the outer periphery of the pulley 52. The pulley 52 is biased in one direction about its axis (a direction that does not wind the cable 48; the opposite direction of arrow R in FIG. 5 ) by a torsion coil spring 53 stretched between the pulley 52 and the base plate 50. For ease of explanation, FIG. 5 shows the torsion coil spring 53 removed from the pulley 52 and the base plate 50.

[0034] One ends of left and right cables 48 are anchored to the upper surface of the pulley 52. The left and right cables 54 are inserted into the left and right legs 22A through left and right through-holes (not shown) formed in the headrest stay 22 near the upper ends of the left and right legs 22A, and are routed from the lower ends of the left and right legs 22A into the seat back 14. As shown in Figures 6 and 7, a pressure-receiving portion 56 included in the release portion 44 is provided within the seat back 14.

[0035] The other ends of the left and right cables 54 routed inside the seat back 14 are connected to the lower end of a pressure receiving plate 58 of the pressure receiving part 56. The pressure receiving part 56 has an abutment member 60 disposed facing the pressure receiving plate 58 from the front side. The pressure receiving plate 58 is formed in a curved shape that protrudes toward the abutment member 60 in the no-load state, and is fixed to the frame 15 of the seat back 14 via a bracket 62. The lower end of this pressure receiving plate 58, to which the other ends of the left and right cables 54 are attached, is in a free state.

[0036] The abutment member 60 is a block-shaped member disposed at an appropriate distance forward from the pressure plate 58. The abutment member 60 is disposed so as not to come into contact with the pressure plate 58 when an occupant seated in the vehicle seat 10 leans against the seat back 14 in normal use. During a rear-end collision, the load from the occupant's back as it sinks into the seat back 14 is applied to the abutment member 60. If this load is equal to or greater than a predetermined magnitude, the abutment member 60 abuts against the curved pressure plate 58, deforming the pressure plate 58 into a substantially straight shape. This causes the lower end of the pressure plate 58 to move downward, pulling the other ends of the left and right cables 54 downward. As a result, the pulley 52, to which one ends of the left and right cables 54 are attached, rotates in the other direction about its axis (the direction of arrow R in FIG. 5 ), and the other end of the cable 48 is wound around the outer periphery of the pulley 52. As a result, the elastic portion 40A of the locking piece 40, to which one end of the cable 48 is locked, is pulled upward, and the lower end of the locking claw portion 40B is released from the engagement of the upper end of the hook 42. In other words, the load received by the pressure-receiving portion 56 is transmitted to the locking portion 38 by the load transmitting portion 46, and the restriction of the locking portion 38 is released. As a result, the plate-like member 30 is compressed in the approximately vertical direction by the biasing forces of the left and right tension coil springs 36 and bent forward, causing the front surface of the headrest main body 26 to bulge forward.

[0037] (Action and effect) In the headrest 20 included in the vehicle seat 10 configured as described above, a headrest main body 26 is supported by a headrest stay 22 connected to the upper end of the seatback 14. A plate-shaped member 30 is disposed within the headrest main body 26. The plate-shaped member 30 is formed in a plate shape and disposed within the headrest main body 26 with its thickness oriented along the front-to-rear direction. In the event of a rear-end collision of the vehicle, the plate-shaped member 30 is compressed and bent by a compression portion in a direction perpendicular to the thickness direction, causing the front surface of the headrest main body 26 to bulge forward (see FIG. 2 ). This brings the front surface of the headrest main body 26 closer to the occupant's head by the distance indicated by arrow S in FIG. 2 , allowing the occupant's head to be supported by the headrest main body 26 early on, thereby preventing whiplash of the occupant. Furthermore, because the plate-shaped member 30 is formed in the above-described plate shape, the arrangement space for the plate-shaped member 30 within the headrest main body 26 can be made thinner in the front-to-rear direction. This contributes to the miniaturization of the headrest main body 26.

[0038] Furthermore, in this headrest 20, when the vehicle collides from behind, the plate-shaped member 30 is compressed by the compression portions 34 in a direction perpendicular to the plate thickness direction, causing the plate-shaped member 30 to bend at the multiple hinge portions 32. These multiple hinge portions 32 make it easy to bend the plate-shaped member as designed.

[0039] The headrest 20 is a so-called saddle-shaped headrest. In the saddle-shaped headrest 20, the lower portion 26B of the headrest main body 26 is formed to be thin in the front-to-rear direction, and the plate-like member 30 embedded in the lower portion 26B is disposed within the lower portion 26B with its plate thickness oriented along the front-to-rear direction, making it easy to ensure space for disposing the plate-like member 30 within the lower portion 26B.

[0040] Furthermore, in this headrest 20, when the vehicle is involved in a rear-end collision, the release portion 44 releases the restriction of the lock portion 38. As a result, the plate-shaped member 30 is compressed in a direction perpendicular to the plate thickness direction and bent by the biasing force of the tension coil spring 36. In this way, the plate-shaped member 30 is bent by the biasing force of the tension coil spring 36, which is a spring, and therefore the configuration can be simplified compared to when the plate-shaped member 30 is bent using the driving force of an actuator, for example.

[0041] Furthermore, in this headrest 20, when the vehicle is involved in a rear-end collision, the pressure receiving portion 56 disposed within the seat back 14 receives a load from the occupant. The load received by the pressure receiving portion 56 is transmitted to the locking portion 38 by the load transmitting portion 46, and the locking portion 38 is released from its restriction. In this way, the locking portion 38 is released from its restriction by the load from the occupant, which simplifies the configuration compared to, for example, a case in which the locking portion 38 is released by controlling an actuator.

[0042] Furthermore, in this headrest 20, when the plate-like member 30 is bent at the hinge portions 32, the multiple reinforcing ribs 33 provided on the side and back surfaces of the plate-like member 30 engage with each other, thereby providing rigidity. This allows the front surface of the headrest main body 26, which bulges forward, to properly support the occupant's head.

[0043] In the above embodiment, the plate-shaped member 30 is configured so that multiple hinge portions 32 are arranged in a generally vertical direction, but this is not limited to this. The plate-shaped member 30 may also be configured so that multiple hinge portions 32 are arranged in a horizontal direction, as in the first modified example shown in Figures 8 and 9.

[0044] Furthermore, in the above embodiment, the present invention has been described as being applied to a so-called saddle-shaped headrest 20. However, the present invention is not limited to this, and can also be applied to a normal headrest. In this case, the headrest stay 70 may be configured as in a second modified example shown in FIG. 10 . This headrest stay 70 includes an inverted-U-shaped first stay 72 and left and right second stays 74 fixed to left and right leg portions 72A of the first stay 72. The upper portions of the left and right second stays 74 are bent toward the center in the left-right direction and open. A cable 54 is routed within one of the second stays 74, and one end of the cable 54 is locked to the elastic portion 40A of the lock piece 40. In this second modified example, the left and right second stays 74 are connected to the left and right headrest supports 16.

[0045] In the above embodiment, the plate-like member 30 is configured to bend at the multiple hinge portions 32, but this is not limiting. For example, the plate-like member may be configured to bend so that the radius of curvature of the curve becomes smaller when the plate-like member is gently curved and convex forward as viewed from the left and right, and is compressed in the up and down direction.

[0046] In addition, in the above embodiment, the plate-shaped member 30 is bent by the biasing force of the tension coil spring 36, which is a spring. However, this is not limited to this, and the plate-shaped member 30 may be bent, for example, by using the driving force of an electric actuator.

[0047] In the above embodiment, when the vehicle collides from behind, the restriction of the locking unit 38 is released by the load from the occupant, but the present invention is not limited to this. For example, when a collision sensor detects a rear-end collision, an actuator such as a solenoid may be activated to release the restriction of the locking unit 38.

[0048] In addition, the present invention can be implemented with various modifications within the scope of the gist thereof. Furthermore, it goes without saying that the scope of the rights of the present invention is not limited to the above-described embodiment. [Explanation of symbols]

[0049] 10 Vehicle seats 12 seat cushions 14 Seat back 20 Headrest 22A Legs 22B Front extension part 22C Lower extension part 26 Headrest body 26A upper part 26B lower part 30 Plate-shaped member 32 Hinge part 33 Reinforcing rib 34 Compression section 36 Coil spring 38 Rock Club 44 Release section 46 Load transmission section 56 Pressure receiving part 70 Headrest stay

Claims

1. a headrest stay connected to an upper end of a seat back of a vehicle seat; a headrest main body supported by the headrest stay; a plate-like member that is formed in a plate shape, is disposed within the headrest body with its plate thickness direction aligned with the front-rear direction of the headrest, is supported by the headrest stay, and is compressed and bent in a direction perpendicular to the plate thickness direction, thereby causing the front surface of the headrest body to bulge forward of the headrest; a compression section that compresses the plate-shaped member in the orthogonal direction when the vehicle is involved in a rear collision; Equipped with The compression section a spring that compresses the plate-like member in the orthogonal direction by a biasing force; a locking portion that restricts the compression of the plate-like member; a release unit that releases the restriction when the vehicle is involved in a rear-end collision; A headrest having a

2. A headrest stay connected to an upper end of a seat back of a vehicle seat; a headrest main body supported by the headrest stay; a plate-like member that is formed in a plate shape, is disposed within the headrest body with its plate thickness direction aligned with the front-rear direction of the headrest, is supported by the headrest stay, and is compressed and bent in a direction perpendicular to the plate thickness direction, thereby causing the front surface of the headrest body to bulge forward of the headrest; a compression section that compresses the plate-shaped member in the orthogonal direction when the vehicle is involved in a rear collision; Equipped with The headrest is configured such that, when the plate-like member is bent, a plurality of reinforcing ribs provided on at least one of the side and back surfaces of the plate-like member engage with each other.

3. 3. The headrest according to claim 1, wherein the plate-like member has a plurality of hinge portions arranged in the orthogonal direction, and the plate-like member bends at the plurality of hinge portions due to the compression.

4. The headrest stay is Left and right legs connected to the upper end of the seat back; Left and right front extension portions extending from upper ends of the left and right leg portions toward the front side of the headrest; Left and right lower extension portions extending from front end portions of the left and right front extension portions to the lower side of the headrest; and The headrest body is An upper portion in which the left and right front extension portions are embedded; a lower portion extending from a front end of the upper portion toward a lower side of the headrest and having the left and right lower extension portions embedded therein; and The headrest according to any one of claims 1 to 3, wherein the plate-like member is embedded in the lower portion and supported by the left and right lower extension portions.

5. The release unit is a pressure receiving portion disposed within the seat back and receiving a load from an occupant in the event of a rear-end collision of the vehicle; a load transmitting portion that transmits the load received by the pressure receiving portion to the locking portion and releases the restriction; The headrest of claim 1 , comprising:

6. A seat cushion and a seat back; The headrest according to any one of claims 1 to 5, wherein the headrest stay is connected to an upper end of the seat back; A vehicle seat comprising:

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