JP3419702B2 - Vehicle seat - 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 having a protective function capable of protecting the lower limbs, waist, etc. of a seated person from the impact of a frontal collision.

[0002]

2. Description of the Related Art In the case of a frontal collision of an automobile or the like (at the time of a frontal collision), the vehicle body is crushed from the front portion, for example, the engine room or the like due to the impact. Then, when the engine room or the like is compressed and deformed to a volume equal to or less than the total volume of the engine or other various kinds of storage under excessive impact,
Under pressure caused by the movement of the stored items, etc., the partition plate between the passenger compartment and the engine room in front of the feet of the front seat occupant, the so-called toe board, may project and deform into the passenger compartment. is there.

[0003]

By the way, the seated person is
Usually, when a danger ahead is sensed, there is a tendency to consciously or unconsciously stretch the leg forward.
In particular, since the driver greatly depresses the brake pedal forward when detecting a collision, his / her foot that extends forward and is rigid is erected rigidly and firmly between the toe board and the seat.

Since the brake pedal is normally located in front of the driver's seat (driver's seat) along the toe board, if the toe board projects and deforms into the passenger compartment due to excessive impact during a frontal collision, etc. However, there is a possibility that the brake pedal may move toward the seated person accordingly.

However, it is not easy for a driver who has his legs strongly stretched with his knees extended to feel the movement of the brake pedal toward the seated person, so it is not easy to react instantly. Even though it is protected, there is a possibility that the safety of the driver's lower limbs, waist, etc. may not be sufficiently maintained against the pressing force from the brake pedal in some cases.

As a structure for protecting against such an impact, for example, a structure in which the lumbar region of the seated person is elastically supported and the compression force from the brake pedal can be absorbed under this elasticity can be considered. However, the elastic support of the waist is negative in terms of stabilizing the sitting posture and reducing fatigue, so further improvement in protection in addition to maintaining seatability is
At present, it has not been sufficiently obtained.

An object of the present invention is to provide a vehicle seat that further enhances the protection of the lower limbs, the waist and the like of a seated person against an impact such as a frontal collision without lowering the seatability and complicating the structure. I am trying.

[0008]

In order to achieve this object, according to the present invention, a pair of base plates extending in the front-rear direction are juxtaposed side by side, and a rearwardly inclined support defined on the front portion of the seat cushion is provided. A fixed rod that movably supports the sloped surface at least forward is installed and fixed between the base plates, and a movable rod that fixedly supports the rear portion of the seat cushion extends to a guide hole that extends in the forward direction and has a substantially long hole shape. Each terminal is installed and pivotally supported between corresponding positions of the base plate.

The guide hole of the base plate has an intermittent shape in which a rear position where the movable rod is inserted and a front position in front of the movable rod are at least partially separated by a segment, and a holding force stronger than a normal seating load. Under this condition, the movable rod can be locked and held at this rear position. A pretensioner that generates a traction force that is greater than the holding force of the guide hole under a traction operation accompanying the input of a predetermined impact signal is installed and connected between a predetermined front fixed member and a movable rod, and When the pretensioner exhibits a pulling motion due to the generation of a shock signal due to the above shock input,
Under the movement of the movable rod from the rear position to the front position accompanying the release of the division of the guide hole, at least the seat cushion can be forcibly rocked in the rearward tilt direction with the upward movement of the front part.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, in a vehicle seat 10 according to the present invention, a pair of base plates 12 are provided.
, Extend in the front-rear direction (left-right direction in FIG. 1) and are juxtaposed side by side, and the fixed rod 14 is installed between its front parts and the movable rod 16 is installed between its rear parts.

As shown in FIG. 1, in the embodiment of the present invention, a seat (vehicle seat) 10 has a so-called seat slide device 22 which supports a runner 18 slidably with respect to a guide rail 20. An upper extending portion which is embodied as a slide sheet and is integral with the runner is defined as the base plate 12 on each of the left and right sides.

The structure of the seat slide device 22 is publicly known, and the basic structure and structure itself are not the gist of the present invention, and therefore will not be described in detail here.

Although the upward extending portion of the runner 18 is defined as the base plate 12 here, it is sufficient if the base plate and the runner can be integrally moved (slide) integrally. Instead, for example, a separate base plate may be integrally fixed to the runner by welding or the like.

As can be seen from FIGS. 1 and 2, as the fixed rod 14, for example, a substantially crank-shaped pipe-shaped rod having the central portion 14a as the crank shaft portion can be used. The fixed rod 14 is attached to the crankshaft portion (central portion) 14
The a is placed below the main shaft portion 14b on each side thereof and is erected between the left and right base plates 12, and the terminals are inserted into and fixed to the pair of left and right fixing brackets 24, and then fixed to the base plate. It is fixed so that it cannot rotate.

Although the fixing rod 14 is fixed to the base plate 12 via the fixing bracket 24 here, the present invention is not limited to this. For example, the fixing rod is directly attached to the base plate, It may be fixed.

Here, in the present invention, the support slope 28 defined in the front portion of the seat cushion 26, that is, the support slope 28 which is inclined rearward when viewed from the horizontal position is movable forward by the fixing rod 14. It is supported. As can be seen from FIG. 1, in the embodiment of the present invention, a partial rearward inclined portion is provided on the back surface of the seat cushion 26 and is used as a supporting inclined surface 28, and this supporting inclined surface is the main shaft portion of the fixed rod. The front portion of the seat cushion is supported so as to be movable forward along the peripheral surface of the main shaft portion by being aligned and placed on 14b.

As shown in FIGS. 1 and 2, in the embodiment of the present invention, the main shaft portion 14b of the fixing rod is covered with a guide bracket 30 having a substantially U-shaped side surface, and the guide bracket is fixed in a flange shape. By fixing the pieces 30a to the supporting slopes 28, the front portion of the seat cushion 26 is connected to the fixed rod 14 so as to be movable forward within the range of the guide piece and not detachable.

With this structure, the range of movement of the seat cushion 26 relative to the fixed rod 14 can be easily defined, and the front portion of the seat cushion can be reliably prevented from separating from the fixed rod. Nevertheless, the stability of the front part of the seat cushion can be easily ensured.

Further, as shown in FIGS. 1 and 2, the movable rod 16 supporting the rear portion of the seat cushion 26 is bent from a solid rod into, for example, a substantially crank shape having a central portion 16a as a crank shaft portion. It is fixedly connected to the rear portion of the seat cushion via a fixing piece 32 that is formed and integrally provided on the main shaft portion 16b. Then, the main shaft portion 16 to the guide hole 34 that extends in the front direction, for example, in the front direction and in the downward direction and has a substantially long hole shape.
The movable rod 16 is erected and pivotally supported between the rear portions of the base plate 12 by inserting and attaching b.

Here, in the present invention, the guide hole 34
Is the rear position 34-1 where the main shaft 16b of the movable rod is inserted.
And a front position 34-2 located in front of it are formed in an interrupted shape in which at least a part is divided by a predetermined segment 36, and the movable rod 16 is locked and held at this rear position. There is.

As shown in FIG. 3 (A), the guide hole 34 has an intermittent shape, for example, a pair of projecting pieces from the side edges are divided into fragments 36. A form in which the position 34-2 is partially divided can be exemplified, and in the guide hole of this form, the movable rod 16 is held at the rear position under the engagement with the protruding piece.

The holding force of the pair of projecting pieces (segment pieces) 36 with respect to the movable rod 16 is set to be equal to or higher than the normal seating load. That is, the pair of projecting pieces 36 are formed in a shape having rigidity that does not easily deform or release the division under the load applied during normal traveling or the like.

As shown in FIGS. 1 and 2, in the present invention, the holding force of the guide hole 34 or more, that is, the protruding piece 36 is used.
The pretensioner 38, which generates a traction force equal to or higher than the rigidity of the crankshaft 14a of the predetermined front fixing member, for example, the fixed rod, is generated by the pretensioner 38 that is generated by the traction operation accompanying the input of the predetermined impact signal.
And the movable rod 16, for example, the crankshaft portion 16a, are erected and connected.

As can be seen from FIG. 4A in addition to FIGS. 1 and 2, the pretensioner 38 is slidable in the axial direction in the cylinder 42 defined in the body 40 of the pretensioner 38. And a movable body 48 extending from the piston to the outside of the main body through a sealing end of the cylinder, that is, a sealing body 46 that seals the cylinder opening.
Then, the pulling operation of pulling the movable body 48 into the main body 40 by the pulling force equal to or larger than the holding force of the guide hole 34, that is, the movable rod 16
The pretensioner 38 is configured so as to exhibit a pulling action of pulling the piston forward by the movement of the piston 44 under the starting action accompanying the input of a predetermined impact signal.

In this embodiment, the movable body
48 is formed of a flexible member such as a wire, and is rotatably connected to the movable rod 16 and further to the crank shaft portion 16a thereof by winding the terminal 48a thereof, and the pretensioner main body 40 is Crank shaft of fixed rod
It is pivotally attached to a bracket 50 which is fixedly attached to and protrudes from 14a via a pivot pin 52. And, like this, the main body 40,
By rotatably connecting the movable body 48 to the fixed rod 14 and the movable rod 16, respectively, the rotation of the pretensioner 38 with respect to each rod during the pulling operation is ensured.

Here, as the starting operation of the pretensioner 38, for example, the operation by the explosion of the medicine can be exemplified.
For example, as shown in FIG. 4 (A), in this type of pretensioner 38, a piston 44 and a sealing body (sealing end) 46
Is defined as the pulling-side chamber 42a of the cylinder 42, and the pulling-side chamber contains a medicine 54 such as an expander.
A detonator 56, which is, for example, filled and ignites under the input of an impact signal, is arranged in the traction chamber.

A shock sensor (not shown) of an airbag device mounted on a steering wheel of an automobile, for example, can be used as a source of a shock signal for igniting the detonator 56.

In such a pretensioner 38, when the detonator 56 exhibits an ignition operation under the input signal from the impact sensor, the generated gas 58 due to the explosion of the medicine 54 is generated.
The expansion of the towing-side chamber 42a by
Moves in the pulling direction, that is, to the left in the figure, as shown in FIG. 4 (B). And, with this piston 44, FIG. 4 (A)
The moving operation of the movable piece 48 from the extended position of FIG. 4 to the pulling position of FIG. 4B is the pulling operation of the pretensioner 38.
By transmitting and applying this pulling operation to the movable rod 16, it is possible to pull the movable rod under a pulling force that exceeds the holding force of the guide hole 34 (see FIG. 3A).

The reference numeral 60 in FIGS. 4A and 4B is an exhaust hole for discharging and exhausting the surplus of the generated gas 58 to the outside of the cylinder 42, and thus the main body 40. As shown in B), the pretensioner 38 is configured to prevent excessive movement of the piston, and thus of the movable body 48, by aligning this exhaust hole in the pulling side chamber 42a after the movement of the piston 44.

The initial state of the seat 10 is shown in FIG. In this initial state, the movable body 48 of the pretensioner 38 is at the extended position, and the main shaft portion 16b of the movable rod is locked and held at the rear position 34-1 of the guide hole (FIG. 4).
(A), see FIG. 3 (A). When a frontal collision (front collision) of the vehicle occurs in such an initial state, the pretensioner 38 performs a predetermined towing operation due to the input of an impact signal from an impact sensor or the like and the explosion of the medicine 54 caused thereby. Is exhibited (see FIG. 4 (B)).

In the present invention, the pretensioner 38
The traction force of the guide hole is the rigidity of the protruding piece 36 of the guide hole, that is, the guide hole.
Since the holding force of 34 is greater than the holding force of 34, when the pretensioner exhibits a pulling action, the movable rod 16 and thus the main shaft portion 16b of the movable rod 16 are pulled.
However, as shown in FIG. 3 (B), the guide piece 34 is forcibly moved to the front position 34-2 thereof while the guide piece 34 is released from the division due to the deformation of the protruding piece.

When the main shaft portion 16b of the movable rod is forcibly moved to the front position 34-2 of the guide piece, the rear portion of the seat cushion 26 is integrally moved forward with the movable rod 16 (to the left in FIG. 1). Since it is pushed out, the forward movement of the support slope 28 along the peripheral surface of the main shaft portion 14b of the fixed rod causes the seat cushion to be forced in the backward inclination direction while lifting the front portion upward as shown in FIG. Rocked to.

As described above, when the seat cushion 26 swings in the rearward tilting direction with the front part moving upward and the rear part falling, the angle of the thigh of the seated person, for example, the driver, moves in the rearward tilting direction together with the seat cushion. Therefore, the knees of the seated person who are stretched by depressing the brake pedal or the like are naturally lifted from the stretched position.
The swinging of the seat cushion 26 under the pulling action of the pretensioner 38 is rapid, and the repulsive force of the seat pad is added to this rapid swinging, so that the driver's knee is simply lifted. Instead of being instantly able to bounce up, this knee bounce lifts the driver's foot away from the brake pedal. Also, even if they are not completely separated, the knees are lifted under the backward inclination of the seat cushion 26, so that the driver's lower limbs can be easily bent, so that the brake pedal is deformed due to the protruding deformation of the toe board into the passenger compartment. Even if it moves toward the seated person, the force can be absorbed under the bending of the lower limbs.

That is, even if the driver pushes his / her foot under the depression of the brake pedal at the time of a frontal collision, the pulled state can be easily released.
Impact from the toe board to the driver's lower limbs, waist, etc., and load input can be suppressed sufficiently. Therefore, the seat 10 can secure higher protection of the driver's lower limbs, waist and the like in a frontal collision or the like.

Since the waist of the driver is not supported with great elasticity, it does not hinder stabilization of the sitting posture or reduction of fatigue. Therefore, it is possible to sufficiently maintain the seating property and the high protection property.

Further, the fixed rod 14 and the movable rod 16 which support the seat cushion 26 are installed between the left and right base plates 12, and the movable rod is locked and retained at the rear position 34-1 of the guide hole 34 and fixed. Since it suffices to connect the rod and the movable rod with the pretensioner 38, the structure is not complicated.

Further, in the seat 10 of the present invention, since the seat cushion 26 is swung in the backward tilting direction, the forward movement of the hip portion at the time of a frontal collision is surely prevented. That is, since so-called slippage at the time of a frontal collision can be prevented, the protective property of the seated person and the certainty of protection can be further improved from this point as well.

Here, in the embodiment of the present invention, the guide hole 34 is embodied as a shape extending forward and downward. However, the seat cushion 26 is tilted in the rearward inclination direction when the movable rod 16 moves forward. Since it is sufficient if the guide hole can be swung, it is not limited to this, and for example, a guide hole is formed as a shape that extends in a substantially horizontal direction, and the guide hole is movable under the movement from the rear position to the front position. The rod may be movable only forward.

However, if the guide hole 34 is provided so as to be inclined forward and downward, the seat cushion 26 is tilted rearward with the rear part thereof depressed, so that the rearward tilt amount becomes large even with the same amount of forward movement. That is, since a large rearward inclination can be obtained even with a short forward movement amount, the certainty of the rearward inclination of the seat cushion 26 can further enhance the protection of the driver.

Further, in this embodiment, the back slope of the seat cushion 26 is partially provided with a rearward inclined portion to form the support slope 28, but the present invention is not limited to this, and for example, a long length formed on a bracket or the like. The longitudinal edge of the hole may serve as a support slope and may be arranged and fixed to the front portion of the seat cushion or the like.

However, as in this embodiment,
If a rearward inclined portion is provided on the back surface of the seat cushion 26 to form a support slope 28, and this support slope is placed on the main shaft portion 14b of the fixed rod, the support slope becomes the fixed rod main shaft portion over a wide range in the axial direction. Because of the contact, the stability and reliability of the support of the front portion of the seat cushion are improved.

Further, in the embodiment, the fixed rod
Although the movable rod 16 and the movable rod 16 are each embodied in a substantially crank shape, the fixed rod and the movable rod are in a substantially crank shape because it is sufficient if the seat cushion 26 can be supported and the pretensioner 38 can be installed and connected. There is no limitation, and these rods may be formed linearly, for example.

In the embodiment of the present invention, as the intermittent shape of the guide hole 34, the form shown in FIG. 3 (A) in which the pair of projecting pieces from the side edges are divided into fragments 36 is illustrated. It is not necessary to limit the number of divided pieces to at least partially divide the rear position 34-1 and the front position 34-2. For example, as shown in FIG. The protruding piece 136 protruding only from may be provided as a segment.

In the guide hole 34 having such a configuration,
Under the engagement with the projecting piece (fragment) 136, the main shaft portion 16b of the movable rod, that is, the movable rod 16 is moved to the rear position 3 of the guide hole.
Hold on to 4-1. Then, for example, the movable rod 16 moves from the rear position 34-1 to the front position 34-2 due to deformation of the protruding piece under the thinning of the lightening hole 64 adjacent to the protruding piece 136 and release of the division. To be done.

Further, the invention is not limited to partial division by the protrusion of the protruding piece from the side edge, and for example, as shown in FIGS. 6 (B) and 6 (C), by a erection member installed between the opposite side edges. ,
The space between the rear position 34-1 and the front position 34-2 of the guide hole may be entirely divided.

FIG. 6 (B) shows an example in which the erection rod is used as the segment piece 236. This erection rod (segment piece) 236 is, for example, bent and formed in a substantially U-shape, and each terminal 23 to the corresponding insertion hole.
Under the fitting of 6a, it is laid between the opposite side edges of the guide hole 34. The movement of the movable rod 16 from the rear position 34-1 to the front position 34-2 is guaranteed under the pulling operation of the pretensioner 38, for example, by unfitting or unscrewing one of the terminals. It is configured to be possible.

The erection rod 236 is preferably a wire having spring characteristics.

Further, an example in which the erection plate 336 is divided into fragments,
It is shown in FIG. The erection plate material (fragment) 336 is, for example,
It is formed with a notch 66, which is a notch for facilitating shearing, and is installed between the opposite side edges of the guide hole 34 by a fixing pin 68 or the like. And the pretensioner 38
The movement of the movable rod 16 from the rear position 34-1 to the front position 34-2 can be ensured by the shearing, for example, at the notch 66 portion under the pulling action of, and further by releasing the division.

The form illustrated here is the guide hole 34.
It is needless to say that the shape may be other than these, since it is only an example of the intermittent shape of.

In the embodiment of the present invention,
Only the seat cushion 26 can be tilted rearward under the pulling action of the pretensioner 38. However, the present invention is not limited to this, and for example, the seat cushion 26 may be tilted backward together with the seat back 70 (see FIG. 1).

Further, in the embodiment of the present invention,
The movable body 48 of the pretensioner is illustrated as a flexible member such as a wire. However, it is sufficient to transmit and apply the traction force due to the movement of the piston 44 to the movable rod 16, and the present invention is not limited to this. For example, a rod having high rigidity may be incorporated as the movable body 48 in the pretensioner 38.

By the way, in the above-mentioned embodiment, the actuation operation of the pretensioner 38 is exemplified by the explosion of the medicine. However, the present invention is not limited to this, and for example, as shown in FIG.
The pretensioner 38 may be configured so that it can be pulled by the biasing force of the compression coil spring 72 that is internally provided and stretched in 2a.

In this structure, the piston 44 is formed, for example, in a substantially bottomed cylindrical shape, and the compression coil spring 72 is stretched from the inside to the sealing body 46, and the piston 44 is connected to the pulling side chamber 42a. Stopper lever 74 that holds the movable body 48 in the contracted position, that is, in the initial extended position.
Is pivotally supported by the support piece 80 of the main body 40 so that it can be inserted into and engaged with the locking hole 78 of the piston through the insertion hole 76 of the main body.
A solenoid 82 that contracts under the input of a predetermined impact signal is rotatably installed and connected between the operation end 74a of the stopper lever and the support piece 84 of the main body 40.

In such a pretensioner 38, when the solenoid 82 contracts under the input of an impact signal from an impact sensor or the like, the pretensioner 38 is rotated accordingly.
Since the stopper lever 74 is disengaged from the engagement hole 78 of the piston as shown in FIG. 7B, the engagement of the piston 44 at the contracted position of the pulling-side chamber 42a by the stopper lever is
This releases it. Then, under the biasing force of the compression coil spring 72, the piston 44 is moved in the pulling direction as shown in FIG. 7 (B), and the movement of the movable piece 48 to the pulling position associated with this piston causes the guide 44 to move. The movable rod 16 can be pulled to the hole front position 34-2 (see FIG. 3 (A)).

In other words, even in the pretensioner 38 having the compression coil spring 72 built-in, the pulling operation can be obtained by the input of the impact signal, so that the swing of the seat cushion 26 in the backward tilting direction at the time of a frontal collision, etc. It can be secured in the same manner as in the above-mentioned embodiment.

In the present invention, a driver seat for an automobile or the like is illustrated as a seat, but the present invention is not limited to this, and the present invention can be applied to other seats of an automobile such as an assistant seat (passenger seat) and a rear seat. May be applied.

The present invention is not limited to seats for automobiles, but may be applied to other seats such as trains, airplanes, and ships.

The above-described embodiments are for explaining the present invention, and do not limit the present invention in any way, and all the modifications and alterations made within the technical scope of the present invention are also the same. Needless to say, it is included in the invention.

[0060]

As described above, according to the vehicle seat of the present invention, the seat cushion is swung in the rearward tilting direction with the upward movement of the front portion at the time of a frontal collision or the like. When the knee is lifted or flipped up by the occupant, the tension of the seated person's foot is released, and even if the seated person's leg is not completely released, the leg of the seated person can be easily bent. In other words, even if the seated person stretches his / her foot at the time of a frontal collision,
Since the stretched state can be easily released, the impact and load input from the toe board to the lower limbs of the seated person, the waist, etc. can be sufficiently suppressed. Therefore, with this seat, it is possible to secure higher protection for the lower limbs, waist, etc. of the seated person in the case of a frontal collision.

Since the waist of the seated person is not supported with great elasticity, the seated posture is not stabilized and fatigue is not reduced. Therefore, it is possible to sufficiently maintain the seating property and the high protection property.

Further, a fixed rod and a movable rod for supporting the seat cushion are installed between the left and right base plates, and the movable rod is locked and held at a rear position of the guide hole, and a pretensioner is provided between the fixed rod and the movable rod. Since it is sufficient to connect with, there is no complicated structure.

Further, if the guide hole is provided so as to be inclined forward and downward, the seat cushion is tilted rearward with the rear part thereof being depressed, and therefore the rearward tilt amount is large even with the same amount of forward movement. In other words, a large backward tilt can be obtained even with a short amount of forward movement, so that the seat cushion can be more reliably protected by the certainty of the backward tilt of the seat cushion.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a vehicle seat according to the present invention in an initial state.

FIG. 2 is a partial schematic perspective view of a vehicle seat.

FIG. 3 is a schematic front view of guide holes in a vehicle seat in an initial state and after operation.

FIG. 4 is a schematic vertical sectional view of a pretensioner in a vehicle seat in an initial state and after operation.

FIG. 5 is a schematic vertical sectional view of the vehicle seat after the operation.

FIG. 6 is a schematic front view of guide holes in a vehicle seat showing a modified example.

FIG. 7 shows a modification of the pretensioner in an initial state,
FIG. 3 is a schematic vertical sectional view after and after operation.

[Explanation of symbols]

10 Vehicle seat 12 base plate 14 Fixed rod 16 Movable rod 26 seat cushion 28 Support slope 34 Guide hole 34-1,34-2 Rear and front positions of guide hole 36,136,236,336 minute fragments 38 pretensioner 42 cylinders 44 piston 48 movable bodies 54 drugs 72 Compression coil spring

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B60N 2/00-2/72

Claims (4)

(57) [Claims] 1. A pair of base plates extending in the front-rear direction are juxtaposed side by side, and a fixed rod for movably supporting at least forward a rearwardly inclined support slope defined in the front portion of the seat cushion is provided between the base plates. Erection,
A movable rod, which is fixed and fixedly supports the rear part of the seat cushion, is installed between the corresponding positions of the base plate by inserting each terminal into the guide hole that extends in the forward direction and has a shaft. The guide hole is an intermittent shape in which the rear position where the movable rod is inserted and the front position in front of the movable rod are at least partially separated by a segment, and the holding force is stronger than a normal seating load. Under this condition, the movable rod can be locked and held at this rear position, and a pretensioner that generates a traction force greater than the holding force of this guide hole under the traction operation accompanying the input of a predetermined impact signal is When the pretensioner is pulled by the impact signal generated by the input of an impact more than a certain value, it is installed and connected between the predetermined front fixing member and the movable rod, and the guide hole is released. Rear under movement of the movable rod to the front position from the position, at least a seat cushion, the vehicle seat has been forced to be swingable rearward tilting direction with the upward movement of the front with. 2. The vehicle seat according to claim 1, wherein the guide hole is formed so as to extend forward and downward, and the rear portion of the seat cushion can be moved forward and downward by the pulling operation of the pretensioner. 3. A cylinder defined inside the main body;
A pretensioner including a piston provided inside the cylinder so as to be slidable in the axial direction; and a movable body extending from the piston to the outside of the main body through the sealed end of the cylinder,
A prescribed chemical is built in the towing side chamber in the cylinder, and a detonator that is ignited under the input of a prescribed impact signal is arranged in the towing side chamber to form a chemical that is caused by ignition in the detonator. The vehicle according to claim 1 or 2, wherein the piston is moved in the pulling direction under the explosion of, and the moving movement of the movable body caused by the movement of the piston can be transmitted and imparted to the movable rod as the pulling movement of the pretensioner. Sheet. 4. A cylinder defined inside the main body;
A pretensioner comprising: a piston provided inside the cylinder so as to be slidable in the axial direction; and a pulling piece having one end connected to the piston and the other end extending outward from the sealed end of the cylinder. A compression coil spring is built in and stretched in the pulling chamber in the cylinder, and the stopper lever locks the piston at a predetermined initial position against the biasing force of the compression coil spring. By the solenoid that can operate under the input of the shock signal of
The stopper lever is held in its locked position, and the piston is unlocked by the stopper lever due to the operation of the solenoid, causing the piston to move in the pulling direction under the biasing force of the compression coil spring, and this piston movement The vehicle seat according to claim 1 or 2, wherein the moving movement of the movable body caused by the above can be transmitted and imparted to the movable rod as a pulling movement of the pretensioner.