JP2008195202A - Vehicular seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid application of an excessive burden to an occupant's waist part, while securing occupant restriction performance by an airbag arranged in a seat cushion. <P>SOLUTION: The lower half body of the occupant restricted on the upper half body by the airbag 25 and a seat belt 26, tries to move forward by inertia in a frontal collision of a vehicle, but the lower half body of the occupant is restricted so as not to slip to the seat cushion 12 by lifting the seat cushion 12 by operating airbags 20 and 22 of first and second airbag devices 18 and 19 arranged in a lower part of the seat cushion 12. Application of an excessive restriction load to the lower half body of the occupant can be prevented while securing restriction performance of the occupant, by reducing restriction force of the lower half body of the occupant to the seat cushion 12, by exhausting gas from a vent hole 20a formed in the airbag 20 of the first airbag device 18, after the first and second airbag devices 18 and 19 operate. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle seat in which a plurality of airbags are arranged below a seat cushion of a vehicle, and the airbag is inflated with a gas generated by an inflator when the vehicle collides to raise the seat cushion.

When the driver's body tries to move forward due to inertia at the time of the frontal collision of the vehicle, the upper body of the occupant is restrained by the airbag that is deployed from the steering wheel or dashboard. There is a possibility that a phenomenon (submarine phenomenon) that slides forward along the dashboard and slides into the lower part of the dashboard occurs, and the restraining effect by the airbag is not sufficiently exhibited. In order to prevent this, the airbag placed under the seat cushion is inflated at the time of a frontal collision of the vehicle, and the seat cushion is lifted upward to press the upper surface of the seat cushion against the occupant's buttocks and thighs. A device that suppresses the occurrence of the submarine phenomenon is known from Patent Document 1 below.
JP-A-10-217818 JP 2001-239872 A

  By the way, it is desirable to strongly restrain the lower body of the occupant by inflating the air bag provided at the lower part of the seat cushion with a high internal pressure at the moment when the vehicle has a frontal collision and a strong forward inertial force acts on the occupant. If the airbag maintains a high internal pressure after the strong inertial force disappears, there is a problem that an excessive load is applied to the occupant's waist and the occupant's burden increases.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to avoid applying an excessive load to the occupant's waist while securing the occupant restraint performance by the airbag provided on the seat cushion.

  In order to achieve the above object, according to the first aspect of the present invention, a plurality of airbags are arranged below a seat cushion of a vehicle, and the airbag is inflated with a gas generated by an inflator when the vehicle collides. In the vehicle seat that raises the seat cushion, a vehicle seat device is proposed in which a vent hole is formed in a part of the plurality of airbags.

  According to a second aspect of the invention, in addition to the configuration of the first aspect, the plurality of airbags include two airbags arranged in the longitudinal direction of the vehicle body, and the vent hole is disposed on the rear side of the vehicle body. A vehicle seat device characterized by being formed in an airbag is proposed.

  According to a third aspect of the present invention, in addition to the configuration of the first aspect, the plurality of airbags include two airbags arranged inside and outside, and the vent hole is formed more than the inner airbag. A vehicular seat device is proposed which is formed at the rear of an outer airbag extending rearward.

  According to the configuration of the first aspect, when the vehicle collides head-on, the lower body of the occupant restrained by the airbag or the seat belt tries to move forward by inertia. By inflating the airbag and raising the seat cushion, the lower body of the occupant is restrained from slipping with respect to the seat cushion, and the occupant can be effectively protected from the secondary collision. After the plurality of airbags are inflated, gas is discharged from a vent hole formed in a part of the plurality of airbags, thereby reducing the restraining force of the occupant's lower body against the seat cushion, and It is possible to prevent an excessive restraining load from being applied to the lower body of the occupant while ensuring the restraint performance of the occupant.

  According to the second aspect of the present invention, the vent hole is formed in the airbag on the rear side of the vehicle body out of the two airbags arranged in the longitudinal direction of the vehicle body. The front part can be kept high and the restraint performance of the occupant can be ensured.

  According to the third aspect of the present invention, the vent hole is formed in the rear portion of the outer airbag that extends rearward from the inner airbag of the two airbags arranged inside and outside, so that gas is discharged from the vent hole. Even after doing so, the front portion of the seat cushion can be kept high to ensure the restraining performance of the occupant.

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

  1 to 3 show a first embodiment of the present invention, FIG. 1 is a side view of a vehicle seat (airbag non-inflated state), and FIG. 2 is a side view (airbag inflated state). FIG. 3 is a graph showing the change over time of the restraining load applied to the occupant's waist by the seat belt.

  As shown in FIG. 1, a seat 11 of a driver's seat of an automobile includes a seat cushion 12 that supports an occupant's buttocks and thighs, and a seat back that is pivotally supported by the seat cushion 12 and supports the occupant's back. 13 and a headrest 14 provided at the upper end of the seat back 13 and supporting the head of the occupant. A pan-like support member 17 is supported on the floor 15 of the vehicle body via a seat base 16, and a rear side first airbag device 18 and a front side second airbag device are folded on the upper surface of the support member 17. 19 is disposed, and the seat cushion 12 is disposed above the first and second airbag devices 18 and 19. That is, the outer peripheral portion of the seat cushion 12 is fixed to the outer peripheral portion of the support member 17, and the first and second airbag devices 18, between the lower surface center portion of the seat cushion 12 and the upper surface center portion of the support member 17, 19 is pinched.

  The first airbag device 18 on the rear side includes a bag-shaped airbag 20 and an inflator 21 that supplies a gas for deployment to the airbag 20, and the second airbag device 19 on the front side includes a bag shape. And an inflator 23 that supplies a gas for deployment to the airbag 22. The inflators 21 and 23 are connected to an acceleration sensor (not shown), and the inflators 21 and 23 are ignited to generate high-pressure gas when a longitudinal acceleration equal to or greater than a command value is detected due to a vehicle collision. A vent hole 20 a is formed in the airbag 20 of the first airbag device 18.

  The first and second airbag devices 18 and 19 are controlled such that the front side second airbag device 19 is first activated and the rear side first airbag device 18 is activated with a predetermined time difference.

  An air bag 25 that restrains the upper body of the driver is disposed on the steering wheel 24, and a seat belt 26 that restrains the upper body of the driver is disposed on the seat 11 on which the driver is seated.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When a longitudinal collision greater than or equal to a predetermined value is detected due to a frontal collision of the vehicle, the airbag 25 provided on the steering wheel 24 is deployed, and the upper body of the driver is restrained in cooperation with the seat belt 26. At this time, if the tension of the seat belt 26 is increased by the pretensioner, the upper body of the driver can be more reliably restrained.

  Although the driver's body tries to move forward due to inertia at the time of the collision, the upper body of the driver is restrained by the airbag 25 and the seat belt 26, so that the lower body of the occupant is placed on the dashboard along the upper surface of the seat cushion 12. There is a possibility that a so-called submarine phenomenon, which tries to slide into the lower part, occurs and the restraining effect by the airbag 25 and the seat belt 26 is not sufficiently exhibited.

  Accordingly, the first and second airbag devices 18 and 19 disposed below the seat cushion 12 are activated simultaneously with the operation of the airbag 25 of the steering wheel 24 at the time of a frontal collision, and the airbags 20 and 22 that are inflated are flexible. The seat cushion 12 having a central portion is lifted upward with respect to the support member 17 so that the upper surface of the seat cushion 12 is pressed against the occupant's buttocks and thighs to suppress the occurrence of the submarine phenomenon. The restraining effect by the airbag 25 and the seat belt 26 can be sufficiently exhibited.

  However, if the inflated state of the airbags 20 and 22 of the first and second airbag devices 18 and 19 continues, there is a problem that the restraining load applied to the occupant's waist becomes excessive.

  FIG. 3A shows a case where a single airbag having no vent hole is disposed at the lower part of the seat cushion and inflated. In this case, since a high restraint load continues even after restraining the lower body of the occupant immediately after the collision, there is a problem that the burden on the occupant's waist is increased. FIG. 3B shows a case where two airbags having no vent hole are arranged below the seat cushion and inflated with a time difference. Also in this case, since a high restraint load continues even after restraining the lower body of the occupant immediately after the collision, there is a problem that a burden on the occupant's waist is increased.

  On the other hand, as shown in FIG. 3C, according to the present embodiment, the first airbag device 18 is activated after the second airbag device 19 is activated first. Since the inner pressure of the airbag 20 is reduced by the action of the vent hole 20a provided in the airbag 20, after restraining the lower body of the occupant with a high load immediately after the collision, the restraining force is quickly reduced to an appropriate magnitude, thereby The burden on the lower back can be minimized.

  Further, the airbag device is divided into the first and second airbag devices 18 and 19, and only one of the airbags 20 is provided with a vent hole 20a, thereby increasing the degree of freedom of setting the change characteristics of the occupant's restraint load. Can do. In particular, since the vent hole 20a is formed in the airbag 20 on the rear side of the vehicle body, out of the two airbags 20 and 22 arranged in the longitudinal direction of the vehicle body, the front side of the seat cushion 12 after the gas is discharged from the vent hole 20a. The restraint performance of the occupant can be secured by keeping the section high.

  Next, a second embodiment of the present invention will be described with reference to FIG.

  In the first embodiment, the rear side first airbag device 18 and the front side second airbag device 19 are provided. In the first embodiment, a large first airbag device 18 disposed outside. A small second airbag device 19 is arranged inside the airbag 20, and a vent hole 20 a is formed in the airbag 20 of the outer airbag 20.

  Also according to the second embodiment, it is possible to achieve the same operational effects as those of the first embodiment described above. In particular, since the vent hole 20a is formed in the rear part of the outer airbag 20 that extends rearward from the inner airbag 22 of the two airbags 20 and 22 arranged inside and outside, the gas is discharged from the vent hole 20a. Even after this, the front portion of the seat cushion 12 can be kept high to ensure the restraining performance of the occupant.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, although the first and second airbag devices 18 and 19 are provided in the embodiment, three or more airbag devices may be provided. In this case, vent holes are provided in the airbags of some airbag devices that are not all of the three or more airbag devices.

  In the embodiment, the present invention is applied to the seat 11 of the driver's seat, but the present invention can be applied to the passenger seat.

Side view of vehicle seat according to first embodiment (airbag non-inflated state) Similarly side view (airbag inflated state) A graph showing the change over time of the restraint load on the occupant's waist by the seat belt Side view of vehicle seat according to second embodiment (airbag inflated state)

Explanation of symbols

12 Seat cushion 20 Air bag 20a Vent hole 22 Air bag 23 Inflator

Claims (3)

A plurality of airbags (20, 22) are arranged below the vehicle seat cushion (12), and the airbags (20, 22) are inflated by gas generated by the inflator (21, 23) when the vehicle collides. In the vehicle seat for raising the seat cushion (12),
A vehicle seat device, wherein a vent hole (20a) is formed in a part of the plurality of airbags (20, 22).   The plurality of airbags are composed of two airbags (20, 22) arranged in the longitudinal direction of the vehicle body, and the vent hole (20a) is formed in the airbag (20) on the vehicle body rear side. The vehicle seat device according to claim 1.   The plurality of airbags include two airbags (20, 22) arranged inside and outside, and the vent hole (20a) of the outer airbag (20) extending rearward from the inner airbag (22). The vehicle seat device according to claim 1, wherein the vehicle seat device is formed at a rear portion.

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