JP3362086B2 - Car seat back device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat back device having an air bag.

[0002]

2. Description of the Related Art An occupant's seat for seating on an automobile is usually constructed as follows.

That is, the seat is provided with a seat cushion on which an occupant sits, and a seat back which extends upward from a rear end portion of the seat cushion and which allows the seated occupant to lean back. There is. The seat back includes a seat back frame framed in a rectangular shape in a front view, and a cushioning material that entirely covers the seat back frame. A headrest is provided in the vicinity of the upper part of the seatback, and the headrest is supported by the seatback frame.

In the above structure, as a first conventional example, in a front view, a cushioning means (which is provided in the internal space surrounded by the seat back frame and is elastically pulled and erected on the seat back frame ( Some have a spring.

As a second conventional example, the same as above when viewed from the front,
Some have a cross member that extends across the inner space of the seat back frame and is erected on the seat back frame (for example, JP-A-4-285506).
Issue).

[0006]

By the way, according to the first conventional example, the vibration force applied to the occupant from the seat toward the front while the vehicle is traveling is effectively absorbed by the buffer means. There is an advantage that the comfort of sitting on the seat is improved.

However, when a large impact force is applied to the seat toward the front, such as during a rear-end collision of an automobile, the occupant moves rearward relative to the seat due to its inertial force, and At the final stage of a rear-end collision, the cushioning means may be elastically largely bent rearward by being pushed by the occupant.

The seated posture of the occupant in the final stage changes greatly from the normal seated posture before the collision, and the changed posture is not constant depending on the magnitude of the impact force. Therefore, the occupant's head may not be accurately supported at the predetermined position of the headrest, that is, the occupant's burden at the time of a rear-end collision may not be sufficiently reduced.

On the other hand, according to the second conventional example, since the cross member is erected on the seat back frame, even if the occupant tries to move rearward largely with respect to the seat due to the impact force, the occupant does not have a cushion material. It is prevented by being pressedly supported by the cross member via the.

Therefore, the seating posture of the occupant at the final stage of the collision is made substantially constant by conforming to the shape of the cross member, so that the head of the occupant is at a predetermined position of the headrest to some extent. Accurately supported.

However, since the cross member has a high rigidity, the impact force is insufficiently absorbed by that amount, which may hinder the reduction of the burden on the occupant.

Further, both the first and second conventional examples have the following problems.

That is, in the normal sitting posture, the occupant slightly separates his / her head from the headrest.

When a rear-end collision occurs in this seated posture, the impact force causes the seat to shockly move forward,
The torso, which is close to the seat cushion on which the person sits, tries to move forward while sliding relative to the seat to some extent, while the head tries to stay in that position, which results in a normal sitting posture. In view of this, the body and the head tend to be displaced relative to each other in the front-rear direction, which is not preferable in reducing the burden on the occupant due to the impact force.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, so that the head of an occupant seated on a seat can be more accurately supported at a predetermined position of a headrest during a vehicle collision. In this case also, the impact force that is about to be given to the occupant from the seat is sufficiently absorbed by the seat back of this seat. Make sure that it does not change significantly from the normal sitting posture before,
Therefore, it is an object of the present invention to more reliably reduce the burden on the occupant against the impact force.

[0016]

A vehicle seat back device of the present invention for achieving the above-mentioned object is a front view.
The seatback 7 is provided in a rectangular frame-shaped seatback frame 9 and an internal space 15 surrounded by the seatback frame 9.
And a cross member 19 that extends across the inner space 15 and is erected on the seat back frame 9. The cushion member 16 is supported on the seat back frame 9. When the headrest 11 is provided and the headrest 11 is supported by the seat back frame 9, the cross member 19
The left and right substantially symmetrical shape, the intermediate portion 21a of the same cross member 19 in the direction transverse to the internal space 15, the rear
The air bag 26 is bent so as to inflate toward the rear side and is positioned rearward of the cushioning means 16, and on the other hand, is rapidly inflated forward based on the impact force applied to the vehicle body, and then gradually contracts in response to an external force. Is provided on the front side of the headrest 11.

In the above case, the headrest 11 is viewed from the side.
The upper front surface of the headrest 11 may be inclined toward the front as it goes from the lower end side to the upper end side, and the air bag 26 may be provided on the upper front surface side of the headrest 11.

[0018]

[Operation] The operation of the above configuration is as follows.

In FIGS. 1 and 4, when the occupant 3 is in a normal sitting posture (A) with respect to the seat 4, a large impact force is applied to the vehicle body toward the front when a rear-end collision occurs. When the seat 4 is shocked and moves forward (in FIG. 4), the occupant 3 relatively moves rearward with respect to the seat 4 due to its inertial force (hereinafter, this is referred to as "rearward movement").
try to. If the "backward movement" is performed in this way, the seated posture of the occupant 3 changes greatly from the normal seated posture (A) described above, and therefore, the head 3a of the occupant 3 is at a predetermined position of the headrest 11. May not be supported accurately.

Therefore, according to the present invention, the seat back 7 is provided with the cross member 19, and the cross member 19 is provided.
Is almost symmetrical when viewed from the front. Therefore, at the final stage of the collision (in FIG. 4), the occupant 3 “moves rearward” due to the impact force, and the head 3a of the occupant 3 is moved to the headrest 11.
When supported by the cross member 19, the body portion 3b of the occupant 3 is supported by the cross member 19 in a pressed state without being biased to the left and right, and further rearward movement is restricted. Will be held in the sitting posture (B).

A midway portion 21 of the cross member 19 is also provided.
a is located on the rear side of the buffer means 16.

Therefore, when the occupant 3 "moves rearward" at the time of a rear-end collision, the occupant 3 is supported by the buffer means 16 before being pressed by the cross member 19 at the final stage. , This allows seat 4 to occupant 3
The impact force applied to the is dampened.

On the other hand, in the normal sitting posture (A), as shown in FIG. 1, the occupant 3 attaches his / her head 3a to the headrest 11a.
It is generally a little further away from. When a rear-end collision occurs in this state (in FIG. 4), in the initial stage (in FIG. 4), the torso 3b of the occupant 3 tries to move forward, while the head 3a tries to remain in that position. That is, the head 3a tries to move rearward relatively rapidly with respect to the headrest 11 (indicated by a broken line in "head movement" in FIG. 4), and the head 3a and the body 3b are relatively moved in the front-rear direction. Displacement is about to occur (in FIG. 4, "relative displacement between head and torso" is shown by a broken line).

Therefore, an air bag 26 is provided on the front side of the headrest 11, which is inflated forward based on the impact force applied to the vehicle body and then gradually contracted by an external force.

For this reason, if a rear-end collision occurs in the normal sitting posture (A) (in FIG. 4), at the initial stage (in FIG. 4), as shown by the chain double-dashed line in FIG. Expands immediately. Then, this air bag 2
As described above, 6 securely supports the head 3a that is about to be accurately supported at the predetermined position of the headrest 11, and holds the head 3a in a state where the head 3a is separated from the headrest 11 by a predetermined dimension. That is, the headrest 11 pushes the head 3a forward with the forward movement of the seat 4 while keeping this state.

Therefore, at the initial stage (in FIG. 4), when the trunk 3b of the occupant 3 moves forward with the seat 4,
The head 3a is prevented from remaining in that position, and the relative displacement between the head 3a and the body 3b is suppressed. Therefore, as shown by "relative displacement between the head and the torso" in FIG. 4, the occupant 3 "moves rearward" in the sitting posture (C) which does not significantly change from the normal sitting posture (A). Will be done.

Further, at the final stage of the collision (in FIG. 4), the body 3b of the occupant 3 "moves backward", so that the body 3b and the head 3a supported by the inflated air bag 26. A relative displacement is about to occur between and. But,
Since the air bag 26 is rapidly inflated and then gradually contracts in response to an external force from the head 3a that is going to move backward, the backward movement of the head 3a with respect to the seat 4 is allowed, and the backward movement of the head 3a is allowed. Then, the head 3a and the body 3b
As described above, the headrest 11 and the cross member 1
The sitting posture (B) supported by 9 and 9 is taken (in FIG. 4).

In the above structure, as shown in FIG.
In a side view, the upper front surface of the headrest 11 may be inclined forward as it goes from the lower end side to the upper end side, and the air bag 26 may be provided on the upper front surface side of the headrest 11.

By doing so, the following action occurs.

That is, in FIG. 5, the front surface side of the seat back 7 of the seat 4 is usually inclined so as to gradually move rearward from the lower end side toward the upper end side. Therefore, when the seat 4 moves forward in the initial stage of a rear-end collision, the occupant 3 sitting on the seat 4 tends to slide rearward and upward along the front side of the seat back 7 of the seat 4. To do.

At this time, as described above, the headrest 1
The front of the upper part of 1 is tilted forward, so this headrest 1
1 suppresses the occupant 3 from climbing up, and due to the rapid inflation of the airbag 26, the head 3 of the occupant 3
The ascending of “a” is more reliably suppressed without impact, and in this case also, the occupant 3 is held in the sitting posture (D) close to the normal sitting posture (A), whereby the The sitting posture (B) in the final stage is adopted.

[0032]

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1)

1 to 4 show a first embodiment.

1 to 3, reference numeral 1 is a passenger compartment of an automobile, and 2 is a floor panel thereof. The arrow Fr in the drawing indicates the front of the vehicle, and the left and right described below means the vehicle width direction toward the front.

A seat 4 for seating a passenger 3 such as a driver or a passenger is installed on a floor panel 2 which is a vehicle body in the passenger compartment 1.

The seat 4 is fixed to the floor panel 2 and the seat cushion 6 on which the occupant 3 sits.
And a seat back 7 extending upward from the rear end portion of the seat cushion 6 to support the back of the occupant 3 who sits down as described above. The seat back 7 is fixed to the seat cushion 6. ing.

The seat back 7 is composed of a seat back frame 9 framed in a rectangular shape by a metal pipe material in a front view, and an elastic cushioning material 10 for covering the seat back frame 9 as a whole. There is. The seat back frame 9 is composed of a pair of side members 9a, 9a located apart from each other on the left and right, an upper member 9b connecting the upper ends of the both side members 9a, 9a, and a lower member 9c connecting the upper and lower ends thereof. And has sufficient rigidity. The front side of the seat back 7 and the seat back frame 9
Is inclined rearward from its lower end toward its upper end.

A headrest 11 is provided near the upper portion of the seat back 7 in the center portion in the left-right direction.
The headrest 11 is detachably fixed to the upper end of the seat back frame 9 by a bracket 12.

Particularly, in the front view shown in FIG. 2, the cushioning means 16 is provided in the internal space 15 surrounded by the seat back frame 9. This buffer means 16 is composed of three springs 17, and each of these springs 17 is the same as above in the internal space 15.
The seat back frame 9 is installed on the left and right side members 9a, 9a of the seat back frame 9 in a state where the seat back frame 9 is stretched left and right so as to cross the inner space 15 and elastically pulled. The buffer means 16
Is provided separately from the cushion material 10, and has a spring constant (k = load / load) greater than that of the cushion material 10.
The amount of bending) is sufficiently large that it is difficult to bend.

Also, in the same as above, when viewed from the above, the above-mentioned internal space 1
A cross member 19 made of a metal pipe is provided so as to extend across the seat 5 and extend over the seat back frame 9. This cross member 19 is the seat back frame 9
An upper member 20 which is erected on the left and right side members 9a, 9a at the upper part of the seat, and a pair of left and right lower members 21 which are erected on the upper member 20 and the lower member 9c of the seat back frame 9 and extend in the vertical direction. 21 and 21 and has sufficient rigidity. The cross member 19 may be made of sheet metal, and its cross section may be L-shaped or U-shaped.

The cross member 19 is bilaterally symmetrical in a front view. Further, the middle portions 21a, 21a of the lower members 21, 21 which are the middle portions of the cross member 19 in the direction crossing the inner space 15 in a front view are bent so as to bulge rearward, and the buffer means 1 is formed.
It is located nearer to the rear side than 6. The front surface of each of the intermediate portions 21a is a concave surface which is recessed rearward in a side view.

When a large impact force is applied to the vehicle body toward the front, such as during a rear-end collision, the airbag device 25 absorbs the impact force toward the occupant 3 on the seat 4 and reduces the burden on the occupant 3. Is provided. The air bag device 25 includes an inflatable and inflatable air bag 26 and a gas generating agent (explosive) that can explosively expand by combustion due to ignition.
And a detection sensor 27 for detecting the impact force, and an ignition means for igniting the gas generating agent by a detection signal of the detection sensor 27. A pair of left and right detection sensors 27 are provided at the rear end of the vehicle body.

The headrest 11 includes a headrest main body 28 supported by the upper member 9b of the seat back frame 9 by the bracket 12 and a contracted air attached to the front surface of the headrest main body 28 which is the front surface side of the headrest 11. The gas generating agent is incorporated into the inside of the headrest body 28.

When a large impact force is applied to the seat 4, such as during a rear-end collision, the gas generating agent explodes due to the detection signal of the detection sensor 27 which detects this, and the gas generated by this explodes the air bag 26. The air bag 26 is immediately sent to the front of the headrest 11 to be inflated.

Further, the air bag 26 is provided with a small hole, and when an external force is applied after the expansion, the gas is gradually released from the small hole, and the air bag 26 is gradually discharged. It is supposed to contract.

In FIGS. 1 and 4, when the occupant 3 is in the normal sitting posture (A) with respect to the seat 4, a large impact force is applied to the vehicle body toward the front when a collision occurs. When the seat 4 is shocked and moves forward (in FIG. 4), the occupant 3 relatively tries to “rearwardly move” with respect to the seat 4 due to its inertial force. If the "backward movement" is performed in this way, the seated posture of the occupant 3 changes greatly from the normal seated posture (A) described above, and therefore, the head 3a of the occupant 3 is at a predetermined position of the headrest 11. May not be supported accurately.

Therefore, as described above, the seat back 7
The cross member 19 is provided on the front side of the vehicle, and the cross member 19 has a substantially left-right symmetric shape when viewed from the front. Therefore, at the final stage of the collision (in FIG. 4), the occupant 3 "rearwardly moves rearward". Then, the head 3a is headrest 11
When it is supported by, the body part 3b of the occupant 3 is supported by the cross member 19 via the cushion material 10 and the cushioning means 16 in a pressed state without being biased to the left and right, and further rearward movement is restricted. At the final stage (in FIG. 4), a predetermined sitting posture (B) similar to the normal sitting posture (A) described above.
Will be held in.

In addition, a midway portion 21 of the cross member 19
Since a is bent so as to bulge rearward and is positioned rearward of the cushioning means 16, when the occupant 3 “rearwardly moves” at the time of a rear-end collision, at the final stage thereof,
Prior to the occupant 3 being pressed and supported by the cross member 19, the cushion material 10 and the cushioning means 16 are provided.
The impact force applied from the seat 4 to the occupant 3 is buffered.

On the other hand, in the normal sitting posture (A), as shown in FIG. 1, the occupant 3 attaches his / her head 3a to the headrest 11a.
It is generally a little further away from. When a rear-end collision occurs in this state (in FIG. 4), in the initial stage (in FIG. 4), the torso 3b of the occupant 3 tries to move forward, while the head 3a tries to remain in that position. That is, the head 3a tries to move rearward relatively rapidly with respect to the headrest 11 (indicated by a broken line as "head movement" in FIG. 4), and the head 3a and the body 3b are moved relative to each other in the front-rear direction. Displacement is about to occur (in FIG. 4, "relative displacement between head and torso" is shown by a broken line).

However, if a rear-end collision occurs in the normal sitting posture (A) (in FIG. 4), at the initial stage (FIG. 4).
Middle), as shown by the chain double-dashed line in FIG. 1, the airbag 26 immediately inflates rapidly. Then, as described above, the air bag 26 surely supports the head 3a that is about to be accurately supported at the predetermined position of the headrest 11, and holds the head 3a away from the headrest 11 by a predetermined dimension. To do. That is, the headrest 11 pushes the head 3a forward with the forward movement of the seat 4 while keeping this state.

Therefore, in the initial stage (in FIG. 4), when the trunk 3b of the occupant 3 moves forward with the seat 4,
The head 3a is prevented from remaining in that position, and the relative displacement between the head 3a and the body 3b is suppressed. Therefore, as shown by "relative displacement between the head and the torso" in FIG. 4, the occupant 3 "moves rearward" in the sitting posture (C) which does not significantly change from the normal sitting posture (A). Will be done.

Further, at the final stage of the collision (in FIG. 4), the torso 3b of the occupant 3 "moves rearward", so that the torso 3b and the head 3a supported by the inflated air bag 26. A relative displacement is about to occur between and. But,
Since the air bag 26 is rapidly inflated and then gradually contracts in response to an external force from the head 3a that is going to move backward, the backward movement of the head 3a with respect to the seat 4 is allowed, and the backward movement of the head 3a is allowed. Then, the head 3a and the body 3b
As described above, the headrest 11 and the cross member 1
The sitting posture (B) supported by 9 and 9 is taken (in FIG. 4).

In FIG. 4, "drum movement", the portion indicated by the broken line shows the case where the cross member 19 is not provided.

(Example 2)

FIG. 5 and FIG. 6 show the second embodiment.

According to this, the headrest 11 is composed of the upper headrest 30 and the lower headrest 31 which are vertically stacked, that is, the headrest 11
The upper part of the headrest 11 is composed of the upper headrest 30, and the lower part of the headrest 11 is composed of the lower headrest 31.

The front surface of the upper headrest 30 is inclined so as to face forward as it goes from the lower end side to the upper end side, and the air bag 26 is provided on the front surface side of the upper headrest 30.

The front side of the seat back 7 of the seat 4 is gradually inclined rearward from the lower end side toward the upper end side. Therefore, when the seat 4 moves forward in the initial stage of a rear-end collision, the occupant 3 sitting on the seat 4 tends to slide rearward and upward along the front side of the seat back 7 of the seat 4. To do.

At this time, as described above, the headrest 1
Since the front side of the upper headrest 30 of No. 1 is tilted forward, the headrest 11 suppresses the occupant 3 from climbing up, and the rapid inflation of the airbag 26 causes the occupant's head 3a to climb up. Further, it is suppressed more reliably without impact, and in this case also, the occupant 3 is held in the sitting posture (D) close to the normal sitting posture (A),
As a result, thereafter, the sitting posture (B) in the final stage is adopted.

In FIG. 6, the bracket 12 for the headrest 11 includes an upper bracket 32 for the upper headrest 30 and a lower bracket 3 for the lower headrest 31.
3 and 3.

The lower bracket 33 has a pair of left and right support pipes 35, 35 fixed to the upper member 9b of the seat back frame 9, and the lower headrest 31 is fitted onto the support pipes 35, 35 from above. The seat back frame 9 is supported by the seat back frame 9 so as to be fitted into and removed from the seat back frame 9.

The upper bracket 32 has an inverted U-shaped support bar 36, and the lower headrest 31 is attached to the upper part of the support bar 36. Above support bar 3
Both lower ends of 6 are removably fitted into the support pipes 35, 35, and nuts 37 are attached to the support pipes 35, 35.
The upper headrest 30 is thereby supported by the seatback frame 9.

According to the above construction, the air bag device 25
Since the upper headrest 30 having the above can be assembled in the final step, the airbag device 25 is prevented from being damaged during the assembling work.

Since the other structure and operation are the same as those of the first embodiment, the same reference numerals are given to the drawings and the description thereof will be omitted.

[0066]

According to the present invention, when viewed from the front, the seat back is provided in the seat back frame framed in a rectangular shape and in the internal space surrounded by the seat back frame and supported by the seat back frame. And a cross member that extends across the inner space and is erected on the seat back frame. The headrest is provided near the upper portion of the seatback in the center portion in the left-right direction. In a vehicle seat back device in which the above-mentioned seat back frame is supported by the above-mentioned seat back frame, the cross member has a substantially symmetrical shape, and the middle portion of the cross member in the direction crossing the internal space is bent so as to bulge rearward. It is located rearward of the cushioning means, while facing forward based on the impact force applied to the vehicle body. Inflated, then the air bag gradually shrinks by an external force is provided on the front side of the headrest. Therefore, the following effects are produced.

That is, when a large impact force is applied to the vehicle body in the forward direction, such as when the vehicle is in a rear-end collision, when the occupant is in a normal sitting posture with respect to the seat, the occupant inertially moves toward the seat. It tries to “move backward” relatively large by force. Then, if the "backward movement" is performed in this manner, the seated posture of the occupant changes significantly from the normal seated posture described above, and thus the head of the occupant may not be accurately supported at the predetermined position of the headrest. There is.

Therefore, in the present invention, as described above,
The seat back is provided with a cross member, and this cross member has a substantially symmetrical shape when viewed from the front.
When the occupant "moves rearward" due to the impact force and its head is supported by the headrest at the final stage of the above-mentioned collision,
The torso of the occupant is supported by the cross member in a biased manner so as not to be biased to the left and right, and further rearward movement is restricted, and the occupant's torso is kept in a predetermined sitting posture even at the final stage.

Therefore, the seating posture of the occupant at the final stage of the collision is made substantially constant by conforming to the shape of the cross member, so that the head of the occupant is accurately located at the predetermined position of the headrest. Supported.

[0070] Further, as described above, the middle portion of the cross member, and is positioned on the rear side than the swelling as folded buffer means toward the rear.

Therefore, when the occupant "moves rearward" during a rear-end collision, the occupant is supported by the cushioning means at the final stage thereof before being supported by the cross member in a pressed state, whereby The shock force applied to the occupant from the seat is buffered.

Therefore, as described above, even when the head of the occupant seated on the seat is accurately supported at the predetermined position of the headrest when the vehicle is hit by a vehicle, the occupant tries to give the occupant the seat. The impact force is sufficiently absorbed by the cushioning means of the seat back, so that the burden on the occupant can be reduced more reliably.

On the other hand, in a normal sitting posture, the occupant generally separates his / her head slightly forward from the headrest. When a rear-end collision occurs in this state, in the initial stage, the occupant's torso tries to move forward, while the head tries to move backward relative to the headrest, trying to remain in that position, A relative displacement in the front-rear direction tends to occur between the head and the body.

Therefore, as described above, an air bag is provided on the front side of the headrest, which is inflated to the front on the basis of the impact force applied to the vehicle body and then gradually contracted in response to an external force.

Therefore, if a rear-end collision occurs in the normal sitting posture, the airbag will immediately inflate suddenly at the initial stage. Then, as described above, the airbag surely supports the head that is about to be accurately supported at the predetermined position of the headrest, and holds the head in a state where the head is separated from the headrest by a predetermined dimension. That is, the headrest pushes the head forward with the forward movement of the seat while keeping this state.

Therefore, in the initial stage, when the torso of the occupant moves forward with the seat, the head is prevented from remaining in that position, and the relative displacement between the head and the torso is prevented. Is suppressed. For this reason, the occupant “moves rearward” in a sitting posture that does not significantly change from the normal sitting posture, and the burden on the occupant during a rear-end collision can be reduced more effectively.

Furthermore, in the final stage of a collision, the occupant's torso "moves backward", so that relative displacement may occur between this torso and the head supported by the inflated airbag. To do. However, since the airbag is rapidly inflated and then gradually contracts in response to an external force from the head trying to move backward, the backward movement of the head with respect to the seat is allowed, and with this backward movement, The head and torso are
As described above, the seated posture is supported by the headrest and the cross member, and as described above, the occupant is properly supported by the seat and the burden on the occupant is reduced.

In the above structure, the front side of the upper portion of the headrest may be inclined forward from the lower end side toward the upper end side in side view, and the air bag may be provided on the upper front side of the headrest.

By doing so, the following action occurs.

That is, the front side of the seat back of the above-mentioned seat is usually gradually increased from the lower end side toward the upper end side,
It is inclined to face backward. Therefore, when the seat moves forward in the initial stage of a rear-end collision, an occupant seated on the seat tends to relatively slide rearward and upward along the front side of the seat back of the seat.

At this time, as described above, since the upper front surface of the headrest is tilted forward, the headrest suppresses the occupant from climbing up, and the air bag suddenly inflates, causing the occupant's head to slip. The rising is suppressed more reliably without impact, and in this case also, the occupant is kept in a sitting posture close to a normal sitting posture, and thereafter, the sitting posture in the final stage is taken. Become. Therefore, the burden on the occupant can be reduced more reliably.

[Brief description of drawings]

FIG. 1 is a side view of a seat according to a first embodiment.

FIG. 2 is a front view of the seat in the first embodiment.

FIG. 3 is a perspective view of a seat in the first embodiment.

FIG. 4 is a diagram showing a time-dependent movement of each part during a rear-end collision in the first embodiment.

FIG. 5 is a diagram corresponding to FIG. 1 in the second embodiment.

FIG. 6 is a front view of the headrest according to the second embodiment.

[Explanation of symbols]

1 car compartment 2 floor panels 3 crew 3a head 3b body 4 seats 6 seat cushion 7 seat back 9 seat back frame 10 cushion material 11 headrest 15 Internal space 16 Buffer means 19 cross members 21a Midway part 25 Air bag device 26 air bags

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-226340 (JP, A) Actual Kaihei 4-65644 (JP, U) Actual public Sho-49-6888 (JP, Y1) (58) Field (Int.Cl. ⁷ , DB name) B60R 21/22 B60N 2/42 B60R 21/04 B60R 21/055

Claims (2)

(57) [Claims] 1. In a front view, the seat back has a rectangular frame-shaped seat back frame, and cushioning means provided in an internal space surrounded by the seat back frame and supported by the seat back frame. A cross member that extends across the inner space and is erected on the seat back frame is provided. A headrest is provided in the lateral center of the seatback near the upper part of the seatback, and the headrest is attached to the seatback frame. in the seat back device was supported automobile, the cross member and the left and right substantially symmetrical, the middle portion of the same cross member in a direction transverse to the internal space, after
The airbag is bent so as to inflate toward one side and is positioned rearward of the cushioning means. On the other hand, an air bag which is rapidly inflated forward based on an impact force applied to the vehicle body, and then gradually contracts in response to an external force is applied. An automobile seat back device provided on the front side of the headrest. 2. The vehicle according to claim 1, wherein, in a side view, the upper front surface of the headrest is inclined forward as it goes from the lower end side to the upper end side, and an air bag is provided on the upper front surface side of the headrest. Seat back device.