Airbag device and occupant protection device

Abstract

To suppress inadvertent displacement, to a seat upper side, of an airbag inflated and deployed from a seat rear side of an upper part of a vehicle seat to a seat front side, when an occupant is restrained.SOLUTION: An airbag device 30 comprises an airbag 32 inflated and deployed from a seat rear side of an upper part of a vehicle seat 12 to a seat front side. The airbag 32 comprises a front-rear chamber 34 and an airbag body 40. The front-rear chamber 34 comprises: a pair of left and right front-rear extension parts 34A that passes through left and right sides of a head H of an occupant D and is inflated and deployed to the seat front side; and a connection part 34B connecting front end parts of the pair of front-rear extension parts 34A in a seat left-right direction. The airbag body 40 is inflated and deployed to the occupant D side at a seat rear side of the connection part 34B later than the front-rear chamber 34. The airbag body 40 comprises a head restraint part 40A as a downward-force application part for applying force toward a seat lower side to the airbag 32 when the occupant is restrained by the airbag 32.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to an airbag device and an occupant protection device including the airbag device.

Background Art

[0002] The airbag device disclosed in Patent Document 1 below includes an inflater that generates high-pressure gas when an impact is input, and a bag body (airbag) that expands and deploys from the seat back of a vehicle seat upon receiving the supply of gas from the inflater. The airbag includes a body support portion that expands on the side opposite to the seat back with the body of an occupant seated on the vehicle seat sandwiched therebetween, and a pair of head support portions that expand on both sides in the width direction of the vehicle seat with the head of the occupant sandwiched therebetween and are connected to the body support portion. An escape portion that penetrates vertically between the pair of head support portions in the deployed state and avoids the head of the occupant is formed in the airbag.

[0003] The airbag device disclosed in Patent Document 2 below includes an inflater and an airbag that is deployed by gas supplied from the inflater. The airbag has a rear inflation portion that expands on the back side of the seat, a pair of side inflation portions that extend forward from both sides in the seat width direction of the rear inflation portion, and a pair of front inflation portions that extend from the pair of side inflation portions toward the center side and are connected to each other at the center to cover the front of the occupant. In this airbag, a gas flow path is formed in the order of the rear inflation portion, the side inflation portions, and the front inflation portions.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the airbag device disclosed in Patent Document 1, a body support portion (airbag body) that expands from the rear side of the seat to the front side of the seat with respect to the occupant is supported by a pair of head support portions (front and rear chambers) that expand on both the left and right sides of the occupant's head. Similarly, in the airbag device disclosed in Patent Document 2, a pair of front inflation portions (airbag body) that expand from the rear side of the seat to the front side of the seat with respect to the occupant is supported by a pair of side inflation portions (front and rear chambers) that expand on both the left and right sides of the occupant's head.

[0006] In each of the above prior arts, when restraining the occupant with the airbag, an input from the occupant's chest is applied to the airbag body, and there is a possibility that the airbag escapes upward above the seat around the base end portion of the front and rear chambers. Further, from the middle to the late stage of restraining the occupant with the airbag, the airbag body may be pushed obliquely upward in front of the seat due to the airbag body being sandwiched between the upper body of the occupant who leans forward due to the impact of the vehicle collision and the occupant's thigh.

[0007] In consideration of the above facts, an object of the present invention is to obtain an airbag device and an occupant protection device that can suppress the airbag that expands and deploys from the rear side of the seat to the front side of the seat at the upper part of the vehicle seat from being inadvertently displaced upward above the seat during occupant restraint.

Means for Solving the Problems

[0008] The airbag device according to the first aspect includes an inflater that generates gas during a vehicle collision, and an airbag to which the gas is supplied and that expands and deploys from the rear side of the seat to the front side of the seat at the upper part of the vehicle seat. The airbag has a pair of left and right front and rear extending portions that expand from both the left and right sides of the head of the occupant seated on the vehicle seat to the front side of the seat, and a front and rear chamber having a connecting portion that connects the front end portions of the pair of front and rear extending portions in the left - right direction of the seat. The airbag device further includes an airbag body that expands and deploys toward the occupant side behind the connecting portion and behind the front and rear chamber, and a downward force applying portion that applies a downward force in the seat - downward direction to the airbag when restraining the occupant with the airbag.

[0009] In the airbag device according to the first aspect, gas generated from an inflater at the time of a vehicle collision is supplied to the airbag, and the airbag expands and deploys from the rear side of the seat to the front side of the seat above the vehicle seat. This airbag has a front-rear chamber, an airbag body, and a downward force applying portion. The front-rear chamber has a pair of left and right front-rear extending portions that expand and deploy toward the front side of the seat through both left and right sides of the head of an occupant seated on the vehicle seat, and a connecting portion that connects the front end portions of the pair of front-rear extending portions in the left-right direction of the seat. The airbag body expands and deploys toward the occupant side behind the connecting portion of the front-rear chamber with a delay. The downward force applying portion applies a force in the downward direction of the seat to the airbag when restraining the occupant with the airbag. Thereby, it is possible to suppress the airbag from being inadvertently displaced upward of the seat.

[0010] In the airbag device according to the second aspect, in the first aspect, the airbag body has a chest and abdomen restraining portion that restrains the chest and abdomen of the occupant below the seat from the front-rear chamber, and a head restraining portion that restrains the head of the occupant above the seat from the front-rear chamber prior to the restraint of the chest and abdomen by the chest and abdomen restraining portion, and the downward force applying portion is the head restraining portion.

[0011] According to the airbag device of the second aspect, the airbag body has a chest and abdomen restraining portion and a head restraining portion. The chest and abdomen restraining portion of the airbag body restrains the chest and abdomen of the occupant below the seat from the front-rear chamber. The head restraining portion of the airbag body restrains the head of the occupant above the seat from the front-rear chamber prior to the restraint of the chest and abdomen by the chest and abdomen restraining portion. Due to the restraint of the head by this head restraining portion, a moment in the downward direction of the seat acts around the base end portion of the pair of front-rear extending portions on the airbag body. Thereby, it is possible to suppress the airbag from being inadvertently displaced upward of the seat.

[0012] In the airbag device according to the third aspect, in the first aspect, the downward force applying portion is a ceiling contact portion provided on the upper portion of the airbag body and contacting the ceiling of the vehicle during the restraint.

[0013] According to the airbag device of the third aspect, when restraining an occupant with the airbag, the ceiling contact portion provided at the upper portion of the airbag main body contacts the ceiling of the vehicle. Thereby, since a reaction force in the direction from the ceiling toward the lower side of the seat is applied to the airbag main body, that is, the airbag, it is possible to suppress the airbag from being inadvertently displaced upward of the seat.

[0014] In the airbag device of the fourth aspect, in the first aspect, the downward force applying portion is a pair of left and right rear tethers each having one end locked to the pair of front and rear extending portions and the other end locked to the seat back or the vehicle body of the vehicle seat on the rear side of the seat from the occupant, and pulling the pair of front and rear extending portions obliquely downward to the rear of the seat during the restraint.

[0015] According to the airbag device of the fourth aspect, the pair of left and right rear tethers have one end locked to the pair of front and rear extending portions of the front and rear chambers and the other end locked to the seat back or the vehicle body of the vehicle seat on the rear side of the seat from the occupant. When restraining an occupant with the airbag, the pair of rear tethers pull the pair of front and rear extending portions obliquely downward to the rear of the seat. Thereby, since a component force in the direction of the lower side of the seat is applied to the airbag, it is possible to suppress the airbag from being inadvertently displaced upward of the seat.

[0016] In the airbag device of the fifth aspect, in the first aspect, the airbag main body is formed such that the dimension in the left - right direction of the seat in the inflated and deployed state gradually decreases toward the lower end portion.

[0017] According to the airbag device of the fifth aspect, since the inflated and deployed airbag body has a dimension in the left-right direction of the seat that gradually decreases toward the lower end, the left and right side surfaces are inclined so as to approach each other as they go toward the lower side of the seat. As a result, even when the arm of the occupant who is bounced obliquely upward in front of the seat by the impact of a vehicle collision interferes with the airbag body, the inclined side surface and the arm slide-contact with each other as described above, so that the arm can be bounced off to the outside in the left-right direction of the seat. As a result, the lifting force applied to the airbag body from the occupant's arm in the upward direction of the seat can be reduced.

[0018] The airbag device of the sixth aspect includes an inflater that generates gas at the time of a vehicle collision, and an airbag that is supplied with the gas and inflates and deploys from the rear side of the seat to the front side of the seat at the upper part of the vehicle seat. The airbag has a front-rear chamber having a pair of front-rear extending portions that inflate and deploy toward the front side of the seat through both the left and right sides of the head of the occupant seated on the vehicle seat, and a connecting portion that connects the front end portions of the pair of front-rear extending portions in the left-right direction of the seat, and an airbag body that inflates and deploys toward the occupant side behind the connecting portion and behind the front-rear chamber. The front-rear chamber is formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat.

[0019] In the airbag device according to the sixth aspect, gas generated from an inflater at the time of a vehicle collision is supplied to the airbag, and the airbag expands and deploys from the rear side of the seat to the front side of the seat above the vehicle seat. This airbag has a front-rear chamber and an airbag main body. The front-rear chamber has a pair of left and right front-rear extending portions that expand and deploy toward the front side of the seat passing through both left and right sides of the head of an occupant seated on the vehicle seat, and a connecting portion that connects the front end portions of the pair of front-rear extending portions in the left-right direction of the seat. The airbag main body expands and deploys toward the occupant side behind the connecting portion of the front-rear chamber with a delay behind the front-rear chamber. The above-described front-rear chamber is formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat. Thereby, it becomes difficult for the arm portion of the occupant who is bounced upward diagonally forward above the seat due to the impact of the vehicle collision to interfere with the front-rear chamber, so that it is possible to prevent or suppress the airbag from being lifted upward above the seat due to the interference.

[0020] In the airbag device according to the seventh aspect, in the sixth aspect, the airbag main body is formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat, and the front portions of the pair of front-rear extending portions are respectively sewn to the left and right side surfaces of the airbag main body in the inflated and deployed state.

[0021] According to the airbag device of the seventh aspect, the airbag main body is formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat. The front portions of the pair of front-rear extending portions are respectively sewn to the left and right side surfaces of the airbag main body in the inflated and deployed state. Thereby, it is possible to easily form the shape of the front-rear chamber in which the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat.

[0022] The airbag device according to the eighth aspect includes an inflater that generates gas during a vehicle collision, and an airbag to which the gas is supplied and that inflates and deploys from the rear side to the front side of the upper portion of the vehicle seat. The airbag has a front-rear chamber having a pair of left and right front-rear extending portions that inflate and deploy from both left and right sides of the head of an occupant seated on the vehicle seat toward the front side of the seat, and a connecting portion that connects the front end portions of the pair of front-rear extending portions in the left-right direction of the seat, and an airbag body that inflates and deploys toward the occupant side behind the connecting portion of the front-rear chamber with a delay. Before inflation and deployment, the airbag has a front portion including the airbag body that is roll-folded from both outer sides in the left-right direction of the seat toward the center side in the left-right direction of the seat.

[0023] In the airbag device according to the eighth aspect, gas generated from the inflater during a vehicle collision is supplied to the airbag, and the airbag inflates and deploys from the rear side to the front side of the upper portion of the vehicle seat. This airbag has a front-rear chamber and an airbag body. The front-rear chamber has a pair of left and right front-rear extending portions that inflate and deploy from both left and right sides of the head of an occupant seated on the vehicle seat toward the front side of the seat, and a connecting portion that connects the front end portions of the pair of front-rear extending portions in the left-right direction of the seat. The airbag body inflates and deploys toward the occupant side behind the connecting portion of the front-rear chamber with a delay. Before inflation and deployment, the airbag has a front (tip side) portion including the airbag body that is roll-folded from both outer sides in the left-right direction of the seat toward the center side in the left-right direction of the seat. This front portion including the airbag body inflates and deploys from the center side in the left-right direction of the seat toward both outer sides in the left-right direction of the seat after being deployed toward the front side of the seat of the occupant by the inflation and deployment of the front-rear chamber. By the inflation and deployment of this front portion including the airbag body, the arm portion of the occupant can be bounced outward in the left-right direction of the seat. As a result, it becomes difficult for the arm portion of the occupant who is bounced obliquely upward and forward by the impact of the vehicle collision to interfere with the airbag, so it is possible to prevent or suppress the airbag from being lifted upward by the interference.

[0024] The occupant protection device according to the ninth aspect includes a vehicle seat on which an occupant sits, and an airbag device according to the first aspect, the sixth aspect, or the eighth aspect mounted on the rear side of the seat above the vehicle seat.

[0025] In the occupant protection device according to the ninth aspect, an airbag device is mounted on the rear side of the seat above the vehicle seat on which the occupant sits. Since this airbag device is of the first aspect, the sixth aspect, or the eighth aspect, the same effects as those of the first aspect, the sixth aspect, or the eighth aspect can be obtained.

Advantages of the Invention

[0026] As described above, in the airbag device and the occupant protection device according to the present invention, it is possible to suppress the airbag that expands and deploys from the rear side to the front side of the seat above the vehicle seat from being inadvertently displaced upward of the seat during occupant restraint.

Brief Description of the Drawings

[0027]

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Figure 30A

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Figure 30C

Embodiment for Carrying out the Invention

[0028] <First Embodiment> Hereinafter, the occupant protection device 10 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 9. In each figure, some reference numerals may be omitted for easy viewing of the drawings. Also, the arrows FR, UP, LH, and RH appropriately marked in each figure indicate the front direction (travel direction), upward direction, left direction, and right direction of the vehicle, respectively. Hereinafter, when simply using the directions of front and rear, left and right, and up and down for explanation, unless otherwise specified, they indicate the front and rear in the vehicle front-rear direction, the left and right in the vehicle left-right direction, and the up and down in the vehicle up-down direction.

[0029] As shown in FIGS. 1 to 5, the occupant protection device 10 is composed of a vehicle seat 12 and an airbag device 30. The vehicle seat 12 is a rear seat of a vehicle (automobile) here, but it may also be a front seat. This vehicle seat 12 has a seat cushion 14, a seat back 16 erected on the upper side of the rear end portion of the seat cushion 14, and a headrest 18 connected to the upper end portion of the seat back 16. The front-rear, left-right, and up-down directions of this vehicle seat 12 coincide with the front-rear, left-right, and up-down directions of the vehicle.

[0030] In FIGS. 1 to 5, a state where a dummy figure D for a collision test is seated on the seat cushion 14 of the vehicle seat 12 is shown as a model of an occupant (seated person) to be protected. The dummy figure D is, for example, AM50 (50th percentile of American adult males) of a dummy for a frontal collision test (Hybrid III). This dummy figure D is seated in a standard seating posture defined by the collision test method, and the vehicle seat 12 is located at a reference setting position corresponding to the seating posture. Hereinafter, for easy understanding of the explanation, the dummy figure D will be referred to as "occupant D".

[0031] The occupant D sitting on the seat cushion 14 of the vehicle seat 12 is restrained by a seat belt 22 provided in the seat belt device 20 (see FIGS. 1 to 3; not shown in FIGS. 4 and 5) to the vehicle seat 12. The seat belt device 20 is a three-point seat belt device, and a so-called seat-attached seat belt device in which a retractor, an anchor, and a buckle (not shown) are provided on the vehicle seat 12.

[0032] The airbag device 30 includes an airbag 32, a pair of inflators 44 (see FIG. 6), and a module case 46 (not shown in FIGS. 8 to 11). The airbag 32 is normally stored in the module case 46 together with the pair of inflators 44 in a folded state. The module case 46 is formed in a hollow rectangular parallelepiped shape. This module case 46 is disposed at the rear of the upper part of the vehicle seat 12 (specifically, behind the upper end of the seat back 16 and the headrest 18), and is fixed to the upper end of the seat back 16 or the vehicle body (not shown).

[0033] The airbag 32 receives gas supply from the pair of inflators 44 and expands and deploys (deploy and inflate) from the rear side to the front side of the upper part of the vehicle seat 12. The airbag 32 has a front-rear chamber 34 and an airbag body 40. The front-rear chamber 34 has a pair of left and right front-rear extending portions 34A that expand and deploy forward through both left and right sides of the head H of the occupant D, and a connecting portion 34B that connects the front end portions of the pair of front-rear extending portions 34A in the left-right direction. The airbag body 40 expands and deploys toward the occupant D side (rear side) behind the connecting portion 34B and behind the front-rear chamber 34.

[0034] The front and rear chambers 34 are formed in a long bag shape by overlapping two long base fabrics 36 and 38 shown in FIG. 6 and sewing the peripheral edges at the sewing part S1. The airbag body 40 is formed in a bag shape by folding a single base fabric 42 shown in FIG. 7 along four fold lines L1, L2, L3, and L4 and sewing it at the sewing part S2. In this sewing part S2, the sewing line SL21 and the sewing line SL22 are sewn, the sewing line SL23 and the sewing line SL24 are sewn, the sewing line SL25 and the sewing line SL26 are sewn, and the sewing line SL27 and the sewing line SL28 are sewn. The above-mentioned base fabrics 36, 38, and 42 are made of, for example, nylon-based or polyester-based fabric materials.

[0035] Both longitudinal ends of the front and rear chambers 34 are a pair of inflator accommodating parts 34C that accommodate a pair of inflators 44. The central part in the longitudinal direction of the front and rear chambers 34 is a connecting part 34B, and the parts between the connecting part 34B and the pair of inflator accommodating parts 34C are respectively front and rear extending parts 34A. The pair of inflators 44 are combustion-type or cold gas-type cylinder inflators, and generate gas when activated. These inflators 44 are controlled to operate by a control device (not shown), and generate gas when the vehicle collides.

[0036] The pair of inflator accommodating parts 34C are arranged separately on the left and right sides within the module case 46. Each inflator 44 accommodated in each inflator accommodating part 34C is arranged in a posture where the axial direction is along the vertical direction of the seat back 16. Each inflator 44 is provided with, for example, a pair of upper and lower stud bolts. The pair of stud bolts penetrate through the inflator accommodating part 34C, the module case 46, and a frame (not shown) of the seat back 16, and nuts are screwed onto each stud bolt. Thereby, the inflator accommodating part 34C, the inflator 44, and the module case 46 are fixed to the frame of the seat back 16.

[0037] The pair of front-and-rear extending portions 34A are each formed in a long tubular shape. The connecting portion 34B has a substantially T-shaped bag-like form communicating with each of the front-and-rear extending portions 34A. The connecting portion 34B is sewn to the airbag body 40 at a sewing portion S3 (see FIGS. 6 and 7) provided at the central portion of the connecting portion 34B. The sewing portion S3 has a substantially inverted trapezoidal shape as an example. Inside the sewing portion S3, a communication hole 48 that communicates the inside of the connecting portion 34B and the inside of the airbag body 40 is formed. The communication hole 48 has a substantially inverted trapezoidal shape as an example. This communication hole 48 is constituted by a through hole 50 formed in the base fabric 38 of the front-and-rear chamber 34 and a through hole 52 formed in the base fabric 42 of the airbag body 40.

[0038] The pair of front-and-rear extending portions 34A, the connecting portion 34B, and the airbag body 40 are normally folded in a predetermined folding manner such as roll folding or bellows folding and housed in the module case 46. When the pair of inflators 44 operate, gas is generated in the pair of inflator housing portions 34C. The gas generated in the pair of inflator housing portions 34C flows toward the connecting portion 34B through the pair of front-and-rear extending portions 34A and is supplied into the airbag body 40 through the communication hole 48. Thereby, the airbag 32 expands and deploys in the order of the pair of front-and-rear extending portions 34A, the connecting portion 34B, and the airbag body 40. When the airbag 32 expands and deploys, a tear line (not shown) formed in the module case 46 is configured to be cleaved by the inflation pressure of the airbag 32. Thereby, the airbag 32 can expand and deploy outside the module case 46.

[0039] The inflated and deployed airbag body 40 restrains an occupant D who moves forward by inertia due to the impact of a vehicle collision from the front side. When restraining the occupant, the front-and-rear chamber 34 is extended in the front-and-rear direction, and the airbag body 40 is compressed in the front-and-rear direction. The shape of the airbag body 40 is set so as to be sandwiched between the thigh portion F and the chest C of the occupant D from the middle to the late stage when restraining the occupant.

[0040] The pair of front and rear extending portions 34A that are inflated and deployed extend in the front-rear direction on both the left and right sides of the head H of the occupant D, and face the head H with gaps on both the left and right sides. The front end portions of the pair of inflated and deployed front and rear extending portions 34A are connected in the left-right direction by the inflated and deployed connecting portion 34B. As shown in FIG. 3, the front-rear chamber 34 including the pair of front and rear extending portions 34A and the connecting portion 34B is inflated and deployed in a U-shape that opens rearward in plan view.

[0041] As shown in FIGS. 1, 2, 4, and 5, at the center portion in the left-right direction of the inflated and deployed connecting portion 34B, there is provided an enlarged portion 34B1 whose dimension in the up-down direction is larger than those of both the left and right end portions of the connecting portion 34B. This enlarged portion 34B1 protrudes downward from both the left and right end portions of the connecting portion 34B. The above-described communication hole 48 is formed in this enlarged portion 34B1. This communication hole 48 is located on the rear side of the center portion in the left-right direction of the inflated and deployed connecting portion 34B. The gas from the inflator 44 is supplied rearward into the airbag body 40 through the communication hole 48. Thereby, the airbag body 40 is inflated and deployed toward the occupant D side (rear side) behind the connecting portion 34B with a delay with respect to the front-rear chamber 34. This airbag body 40 is inflated and deployed rearward after passing through the gap between the head H of the occupant D and the ceiling of the vehicle (not shown) from the rear side to the front side by the inflation and deployment of the front-rear chamber 34. The inflated and deployed airbag body 40 faces the head H, chest C, and abdomen B of the occupant D with a gap from the front side.

[0042] A pair of left and right front upper tethers 56 and a pair of left and right front lower tethers 58 are attached to the airbag 32 having the above configuration. The front upper tethers 56 and the front lower tethers 58 are formed in a long strip shape by, for example, a nylon-based or polyester-based cloth material. The cloth material constituting the front upper tethers 56 and the front lower tethers 58 is configured to be less stretchable than the base fabrics 36, 38 constituting the front-rear chamber 34 and the base fabric 42 constituting the airbag body 40. This low stretchability can be adjusted by the material and thickness of the cloth.

[0043] A pair of front upper tethers 56 connect the left and right parts on the upper front side of the airbag body 40 that expand and deploy above the front and rear chambers 34 and the front parts of the pair of front and rear extending parts 34A, respectively. Each one end of the pair of front upper tethers 56 is sewn to the left and right parts on the upper front side of the airbag body 40 that expand and deploy above the front and rear chambers 34, respectively. Each other end of the pair of front upper tethers 56 is sewn to the front parts of the pair of front and rear extending parts 34A, respectively. The pair of front upper tethers 56 suppress the upward rotation of the airbag body 40 around the connecting part 34B when the inflation and deployment of the airbag 32 are completed.

[0044] A pair of front lower tethers 58 connect the left and right parts on the lower part of the airbag body 40 that expand and deploy below the front and rear chambers 34 and the front parts of the pair of front and rear extending parts 34A, respectively. Each one end of the pair of front lower tethers 58 is sewn to the left and right parts on the lower part of the airbag body 40 that expand and deploy below the front and rear chambers 34, respectively. Each other end of the pair of front lower tethers 58 is sewn to the front parts of the pair of front and rear extending parts 34A, respectively. The pair of front lower tethers 58 suppress the downward rotation of the airbag body 40 around the connecting part 34B when the inflation and deployment of the airbag 32 are completed.

[0045] The above airbag device 30 is provided with a control device (ECU) not shown that controls the operation of the pair of inflators 44. The control device is electrically connected to the pair of inflators 44 and a collision sensor not shown. Based on the information from the collision sensor, the control device can detect or predict the occurrence of various forms of frontal collisions (or the inevitability of frontal collisions) for the applicable vehicle for each collision form described later.

[0046] When the control device detects or predicts a frontal collision based on the information from the collision sensor, it operates the pair of inflators 44. The forms of frontal collisions in which the control device operates the inflator 44 include, in addition to full wrap frontal collisions, offset frontal collisions such as oblique collisions and micro wrap collisions.

[0047] When the pair of inflators 44 operate, due to the pressure of the gas generated within the pair of inflator accommodation portions 34C of the front and rear chambers 34, the pair of front and rear extending portions 34A are unfolded from the rear end side (base end side) in the folded state and expand and deploy toward the front side. Due to the expansion and deployment of this pair of front and rear extending portions 34A, the front portion of the airbag 32 including the connecting portion 34B and the airbag body 40 is deployed toward the front side. At this time, the front portion of the airbag 32 passes through the gap between the head H of the occupant D and the ceiling of the vehicle from the rear side toward the front side. Thereafter, the gas supplied to the connecting portion 34B of the front and rear chambers 34 is supplied to the airbag body 40 through the communication hole 48, and the airbag body 40 is configured to expand and deploy toward the occupant D side.

[0048] As shown in FIG. 8, the airbag body 40 has a chest and abdomen restraint portion 40B that restrains the chest C and abdomen B of the occupant D below the front and rear chambers 34, and a head restraint portion 40A that restrains the head H of the occupant D above the front and rear chambers 34. The shape of this airbag body 40 is set such that the head H is restrained by the head restraint portion 40A prior to the restraint of the chest C and abdomen B by the chest and abdomen restraint portion 40B. This head restraint portion 40A corresponds to the "downward force applying portion" in the present invention. In FIG. 8, reference numeral 13 denotes the front seat of the vehicle.

[0049] (Function and Effect) Next, the function and effect of the first embodiment will be described.

[0050] The occupant protection device 10 according to the present embodiment includes a vehicle seat 12 on which an occupant D of a vehicle (automobile) is seated, and an airbag device 30 that protects the occupant D during a collision of the vehicle. In this airbag device 30, gas generated from the pair of inflators 44 during a collision of the vehicle is supplied to the airbag 32, and the airbag 32 expands and deploys from the rear side to the front side above the vehicle seat 12.

[0051] This airbag 32 has a front-rear chamber 34 and an airbag body 40. The front-rear chamber 34 has a pair of left and right front-rear extending portions 34A that expand and deploy forward through both left and right sides of the head H of the occupant D, and a connecting portion 34B that connects the front end portions of the pair of front-rear extending portions 34A in the left-right direction. The airbag body 40 expands and deploys toward the occupant D behind the connecting portion 34B with a delay relative to the front-rear chamber 34. This airbag body 40 has a chest and abdomen restraint portion 40B and a head restraint portion 40A. The chest and abdomen restraint portion 40B restrains the chest C and abdomen B of the occupant D below the front-rear chamber 34. The head restraint portion 40A restrains the head H of the occupant D above the front-rear chamber 34 prior to the restraint of the chest C and abdomen B by the chest and abdomen restraint portion 40B. Due to the restraint of the head H by this head restraint portion 40A, a downward moment M1 (see FIG. 8) acts on the airbag body 40 around the base end portions of the pair of front-rear extending portions 34A. Thereby, it is possible to suppress the airbag 32 from being inadvertently displaced upward.

[0052] That is, in the present embodiment, at the initial stage of restraint of the occupant D by the airbag 32, before a load F2 is input from the chest C and abdomen B to the chest and abdomen restraint portion 40B of the airbag body 40, a load F1 is input from the head H to the head restraint portion 40A of the airbag body 40. Thereby, a downward moment M1 acts on the airbag 32 around the base end portions of the pair of front-rear extending portions 34A due to this load F2. Thereby, the upward moment acting on the airbag 32 due to the load F2 is canceled out, so that it is possible to suppress the airbag 32 from being inadvertently displaced upward.

[0053] Regarding the above effects, a supplementary explanation will be given using the first comparative example shown in FIGS. 9 to 11. In FIGS. 9 to 11, the same reference numerals are given to the same configurations as in the present embodiment. In this first comparative example, the airbag main body 40 does not include the head restraint portion 40A, but the other configurations are the same as in the present embodiment. In this first comparative example, at the initial stage of restraining the occupant D by the airbag 32, a load F2 is input from the chest C and the abdomen B to the chest and abdomen restraint portion 40B of the airbag main body 40, so that the airbag 32 escapes upward (see arrow RA in FIG. 9). This is because, as shown by arrow MA in FIG. 10, the base ends of the pair of front and rear extending portions 34A, which are the bases of the airbag 32, are located above the input position of the load F2 to the airbag main body 40, so that an upward moment M2 around the base ends of the pair of front and rear extending portions 34A acts on the airbag 32. In the present embodiment, the moment M1 can cancel the moment M2, so that the inadvertent upward displacement of the airbag 32 can be suppressed.

[0054] Also, in this first comparative example, as shown in FIG. 11, from the middle to the late stage of restraining the occupant by the airbag 32, the airbag main body 40 is sandwiched between the upper body of the occupant D who leans forward due to the impact of the vehicle collision and the thigh portion F of the occupant D. As a result, the airbag main body 40 is pushed forward and obliquely upward (see arrow PO in FIG. 11), and the airbag 32 tends to be inadvertently displaced upward. In this regard, in the present embodiment, the above load F1 continues to be applied to the head restraint portion 40A from the initial stage to the late stage of restraining the occupant by the airbag 32, so that the upward displacement of the airbag 32 due to the above extrusion can be suppressed.

[0055] Further, in the present embodiment, the airbag body 40 has gas supplied from the inflator 44 through a communication hole 48 located on the rear side of the center in the left-right direction of the connecting portion 34B of the front-rear chambers 34 in the inflated and deployed state of the front-rear chambers 34. That is, the gas that has passed through the pair of front-rear extending portions 34A and the connecting portion 34B of the front-rear chambers 34 is supplied into the airbag body 40 from the communication hole 48 toward the rear side. Thereby, the airbag body 40 can be inflated and deployed with a sufficient delay with respect to the front-rear chambers 34. As a result, for example, it becomes easy to inflate and deploy the airbag 32 by passing through a narrow gap between the head H of the occupant D and the ceiling of the vehicle (not shown).

[0056] Further, in the present embodiment, after the front-rear chambers 34 are inflated and deployed, the airbag body 40 inflates and deploys toward the occupant D side (i.e., the rear side) on the rear side of the connecting portion 34B. Thereby, the gap between the airbag body 40 and the occupant D becomes smaller. As a result, since the occupant D is restrained by the airbag body 40 at an early stage, the initial restraint performance of the occupant D by the airbag body 40 can be improved.

[0057] That is, in the present embodiment, the airbag body 40 inflates and deploys toward the rear side after passing through the gap between the head H of the occupant D and the ceiling of the vehicle from the rear side to the front side by the inflation and deployment of the front-rear chambers 34. Thereby, it becomes easier to prevent the airbag body 40 from getting stuck in the above-described gap, and it becomes easier to prevent a malfunction in the deployment of the airbag.

[0058] Next, another embodiment of the present invention will be described. Regarding the configuration and operation that are basically the same as those of the described embodiment, the same reference numerals as those of the described embodiment are given and the description thereof is omitted.

[0059] <Second Embodiment> FIG. 12 shows, in a side view, the state of initial occupant restraint by the airbag 32 in the occupant protection device 60 according to the second embodiment. FIG. 13 shows, in a side view, the state of intermediate occupant restraint by the airbag 32 in the occupant protection device 60 according to the second embodiment. In FIGS. 12 and 13, illustration of the module case 46 is omitted.

[0060] In this embodiment, a ceiling contact portion 40T is provided at the upper part of the airbag body 40, and the upper part of the airbag body 40 is enlarged upward. The upper part of the airbag body 40 provided with the ceiling contact portion 40T is formed such that the width in the front-rear direction decreases as it goes upward when the inflated and deployed state of the airbag body 40 is viewed from the side. As shown in FIG. 12, the upper end portion of the ceiling contact portion 40T contacts the ceiling R of the vehicle at the initial stage of occupant restraint by the airbag 32. Thereby, a downward reaction force from the ceiling R is applied to the airbag body 40, that is, the airbag 32, so that it is possible to suppress the airbag 32 from being inadvertently displaced upward at the initial stage of occupant restraint.

[0061] As shown in FIG. 13, from the intermediate stage to the late stage of occupant restraint by the airbag 32, the airbag body 40 is sandwiched between the upper body of the occupant D who leans forward due to the impact of the vehicle collision and the thigh portion F of the occupant D. Thereby, the airbag body 40 is pushed out obliquely upward in the front, but the upward displacement of the airbag 32 is suppressed by the contact between the ceiling contact portion 40T and the ceiling R.

[0062] The airbag body 40 provided with the ceiling contact portion 40T as described above expands and deploys with a delay in the front and rear chambers 34 by the gas passing through the front and rear chambers 34 being supplied through the communication hole 48, similarly to the first embodiment. For this reason, as shown in FIGS. 14 to 16, the airbag body 40 expands and deploys after a part of the airbag 32 passes through the gap G between the head H of the occupant D and the ceiling R of the vehicle. Also in this embodiment, substantially the same effects as those of the first embodiment are obtained. In FIGS. 14 to 16, the airbag 32 is schematically illustrated for convenience of explanation. Further, in this embodiment, the head restraint portion 40A does not have to restrain the head H prior to the restraint of the chest C and the abdomen B by the chest and abdomen restraint portion 40B.

[0063] <Third Embodiment> FIG. 17A shows a side view of the state in which the inflation and deployment of the airbag 32 is completed in the occupant protection device 70 according to the third embodiment. FIG. 17B shows a side view of the state in the later stage of occupant restraint by the airbag 32 in the occupant protection device 70 according to the third embodiment. In FIG. 17B, the illustration of the module case 46 is omitted.

[0064] This embodiment includes a pair of left and right rear tethers 54 attached to the airbag 32. Each one end portion of the pair of rear tethers 54 is respectively locked (sewn) to the longitudinal intermediate portion of the pair of front and rear extending portions 34A (specifically, the front portion of each of the inflated and deployed front and rear extending portions 34A). Each other end portion of the pair of rear tethers 54 is respectively locked to the seat back 16 or a vehicle body (not shown) on the rear side of the occupant D. In the inflated and deployed state of the airbag 32, the pair of rear tethers 54 extend in the front-rear direction below the pair of front and rear extending portions 34A. In this state, the pair of rear tethers 54 are inclined so as to descend rearward. Thereby, the pair of front and rear extending portions 34A are configured to be drawn diagonally downward rearward by the pair of rear tethers 54 (see the arrow PI in FIG. 17B). Thereby, when the inflation and deployment of the airbag 32 is completed, the airbag 32 is suppressed from swinging in the vertical direction and the front-rear direction.

[0065] Further, as described above, when the pair of front and rear extending portions 34A are drawn in by the pair of rear tethers 54, a downward component force is applied to the airbag 32. Therefore, a moment M1 acting downward around the base end portion of the pair of front and rear extending portions 34A acts on the airbag 32. Thus, similar to the first embodiment, it is possible to prevent the airbag 32 from being inadvertently displaced upward. Further, the pair of rear tethers 54 are extended in the front-rear direction together with the front-rear chambers 34 when restraining the occupant by the airbag body 40. These rear tethers 54 receive and support the load applied from the occupant D to the airbag body 40 together with the front-rear chambers 34.

[0066] As described above, when the pair of front and rear extending portions 34A are drawn in, when restraining the occupant by the airbag 32, the lower surfaces of the pair of front and rear extending portions 34A are configured to contact the left and right shoulders K of the occupant D (see FIG. 17B). Thereby, regardless of the physical differences of the occupant D, the vertical position of the airbag body 40 with respect to the head H of the occupant D can be stabilized. In this embodiment, the occupant D is AM50. However, even when the occupant D is AM95 (95th percentile of American adult males) or the occupant D is AF05 (5th percentile of American adult females), the length of the pair of rear tethers 54 is set so that the lower surfaces of the pair of front and rear extending portions 34A contact the left and right shoulders K of the occupant D. In this embodiment, the head restraint portion 40A does not have to restrain the head H prior to the restraint of the chest C and abdomen B by the chest and abdomen restraint portion 40B.

[0067] <Fourth Embodiment> FIG. 18 shows, in a front view, a state in which the inflation and deployment of the airbag 32 are completed in the occupant protection device 80 according to the fourth embodiment. FIG. 19 shows, in a front view, a state in the middle of restraining the occupant by the airbag 32 in the occupant protection device 80 according to the fourth embodiment. In FIGS. 18 and 19, for convenience of explanation, the airbag 32 and the occupant D are schematically shown.

[0068] In this embodiment, when the inflated and deployed state of the airbag 32 is viewed from the front-rear direction, the lower part of the airbag body 40 is configured to form an inverted triangle. The airbag body 40 is formed such that the dimension in the left-right direction in the inflated and deployed state gradually decreases toward the lower end portion. The lower part of the airbag body 40 in the inflated and deployed state has left and right side surfaces 40L and 40R inclined so as to approach each other as they go downward. In this embodiment, the configuration other than the above is the same as that of the third embodiment, but the pair of rear tethers 54 may be omitted.

[0069] As shown in FIGS. 20 to 23, when restraining the occupant by the airbag 32, the front-rear chamber 34 is extended in the front-rear direction, and the airbag body 40 is compressed in the front-rear direction. As shown in FIG. 23, in the latter stage of occupant restraint by the airbag 32, the arm portion A of the occupant D is bounced upward and obliquely forward by the impact of the vehicle collision. As shown in FIG. 18, before the occupant is restrained by the airbag 32, when the arm portion A is near the center in the left-right direction of the body of the occupant D, the arm portion A bounced upward as described above interferes with the airbag body 40. Even in such a case, the arm portion A is bounced off to the outside in the left-right direction by the sliding contact between the inclined side surfaces 40L and 40R and the arm portion A as described above. As a result, the upward lifting force applied from the arm portion A to the airbag body 40 can be reduced.

[0070] That is, as in the second comparative example shown in FIGS. 24 and 25, in a configuration where the dimension in the left-right direction in the inflated and deployed state of the airbag body 40 does not gradually decrease toward the lower end portion of the airbag body 40, the airbag 32 may be lifted upward because the arm portion A bounced upward and obliquely forward interferes with the airbag body 40 (see FIG. 25). In this embodiment, since the lifting force applied from the arm portion A to the airbag body 40 can be reduced, it is possible to suppress the airbag 32 from being inadvertently displaced upward.

[0071] <The Fifth Embodiment> FIG. 26 shows a state in which the airbag 32 has been inflated and deployed in the occupant protection device 90 according to the fifth embodiment, in a plan view. In this embodiment, the airbag body 40 is formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat, and the front portions of a pair of front-rear extending portions 34A are sewn to the left and right side surfaces of the airbag body 40 in the inflated and deployed state, respectively. As a result, the front-rear chamber 34 is formed such that the dimension in the left-right direction in the inflated and deployed state is smaller on the front side than on the rear side. As shown in FIG. 27, in the base fabric 42 constituting the airbag body 40 described above, the trapezoidal upper surface panel 42A forming the upper surface of the airbag body 40 has a shorter upper base than the base fabric 42 in the first embodiment. In this embodiment, the configuration other than the above is the same as that in the first embodiment.

[0072] In this embodiment, since the front-rear chamber 34 is formed such that the dimension in the left-right direction in the inflated and deployed state is smaller on the front side than on the rear side, it is less likely that the arm portion A of the occupant D who is bounced upward diagonally forward by the impact of a vehicle collision will interfere with the front-rear chamber 34. As a result, it is possible to prevent or suppress the airbag 32 from being lifted upward due to the above interference. Moreover, since the upper surface panel 42A of the base fabric 42 of the airbag body 40 may be formed in a trapezoidal shape with a short upper base, the front-rear chamber 34 having the above shape can be easily manufactured.

[0073] <Sixth Embodiment> In FIGS. 28A to 28C, in the occupant protection device 100 according to the sixth embodiment, a state in which the airbag 32 in the initial stage of inflation and deployment is passing through the gap G between the head H of the occupant D and the ceiling R of the vehicle is shown in a side view, a plan view, and a front view. In FIGS. 29A to 29C, in the occupant protection device 100 according to the sixth embodiment, a state in which the airbag 32 has finished passing through the gap G is shown in a side view, a plan view, and a front view. In FIGS. 30A to 30C, in the occupant protection device 100 according to the sixth embodiment, a state in which the inflation and deployment of the airbag 32 is completed is shown in a side view, a plan view, and a front view. Note that, for convenience of explanation, the airbag 32 is schematically illustrated in FIGS. 28A to 30C.

[0074] In this embodiment, before inflation and deployment, the front portion 32F of the airbag 32 including the airbag body 40 is roll-folded from both outer sides in the left-right direction toward the center in the left-right direction. As shown in FIGS. 29A to 29C, the front portion 32F is deployed toward the front side of the occupant D by the inflation and deployment of the front and rear chambers 34, and then expands and deploys from the center in the left-right direction toward both outer sides in the left-right direction. As shown in FIG. 29C, in the above roll folding, the left side portion of the front portion 32F is folded so as to be in a left-handed roll shape when viewed from the front of the vehicle (so-called outer roll folding), and the right side portion of the front portion 32F is folded so as to be in a right-handed roll shape when viewed from the front of the vehicle (so-called outer roll folding). In this embodiment, the configuration other than the above is the same as that of the first embodiment.

[0075] Also in this embodiment, the same effects as those of the first embodiment can be obtained. Moreover, in this embodiment, after the front portion 32F of the airbag 32 is deployed toward the front side of the occupant D by the inflation and deployment of the front and rear chambers 34, it expands and deploys from the center in the left-right direction toward both outer sides in the left-right direction. By the expansion and deployment of the front portion 32F, the arm A of the occupant D can be bounced outward in the left-right direction. As a result, it becomes difficult for the arm A, which is bounced obliquely upward to the front by the impact of a vehicle collision, to interfere with the airbag 32, so that it is possible to prevent or suppress the airbag 32 from being lifted upward due to the interference.

[0076] The present invention has been described above with reference to several embodiments. However, the present invention can be implemented with various modifications without departing from the gist thereof. Needless to say, the scope of rights of the present invention is not limited to the above-described embodiments.

Explanation of Reference Numerals

[0077] 10 Occupant protection device 12 Vehicle seat 30 Airbag device 32 Airbag 32F Front portion 34 Front and rear chambers 34A Front and rear extending portion 34B Connecting portion 40 Airbag body 40A Head restraint portion 40B Chest and abdomen restraint portion 40T Ceiling contact portion 44 Inflator 54 Rear tether 60 Occupant protection device 70 Occupant protection device 80 Occupant protection device 90 Occupant protection device 100 Occupant protection device D Occupant H Head C Chest B Abdomen

Claims

1. An inflator that generates gas upon collision of a vehicle, An airbag that is supplied with the gas and expands and deploys from the rear side to the front side of the seat at the upper part of the vehicle seat, and comprising, The airbag, A pair of left and right front - rear extending portions that expand and deploy from both left and right sides of the head of an occupant sitting on the vehicle seat to the front side of the seat, and a connecting portion that connects the front end portions of the pair of front - rear extending portions in the left - right direction of the seat, and a front - rear chamber having the same; An airbag body that expands and deploys toward the occupant side behind the connecting portion and behind the front - rear chamber at the rear side of the seat; A downward - force applying portion that applies a downward force to the airbag when restraining the occupant by the airbag; and having, The airbag body, A chest - abdomen restraining portion that restrains the chest and abdomen of the occupant below the seat from the front - rear chamber; A head restraining portion that restrains the head of the occupant above the seat from the front - rear chamber prior to the restraint of the chest and abdomen by the chest - abdomen restraining portion; and having, The downward - force applying portion is the airbag device that is the head restraining portion.

2. An inflator that generates gas upon collision of a vehicle, and An airbag that is supplied with the gas and expands and deploys from the rear side to the front side of the seat at the upper part of the vehicle seat, and comprising, The airbag, A pair of left and right front - rear extending portions that expand and deploy from both left and right sides of the head of an occupant sitting on the vehicle seat to the front side of the seat, and a connecting portion that connects the front end portions of the pair of front - rear extending portions in the left - right direction of the seat, and a front - rear chamber having the same; An airbag body that expands and deploys toward the occupant side behind the connecting portion and behind the front - rear chamber at the rear side of the seat; When restraining the occupant with the airbag, a downward force applying portion that applies a downward force to the airbag in the seat downward direction; and has The downward force applying portion is an airbag device provided at the upper part of the airbag main body and is a ceiling contact portion that contacts the ceiling of the vehicle during the restraint.

3. An inflater that generates gas during a vehicle collision; An airbag that is supplied with the gas and expands and deploys from the rear side to the front side of the seat above the vehicle seat; and includes The airbag A front-rear chamber having a pair of front-rear extending portions that expand and deploy toward the front side of the seat through both left and right sides of the head of the occupant sitting on the vehicle seat, and a connecting portion that connects the front end portions of the pair of front-rear extending portions in the seat left-right direction; An airbag main body that expands and deploys toward the occupant side behind the front-rear chamber on the rear side of the connecting portion; When restraining the occupant with the airbag, a downward force applying portion that applies a downward force to the airbag in the seat downward direction; and has The downward force applying portion is a pair of rear tethers whose one end portions are locked to the pair of front-rear extending portions, and the other end portions are locked to the seat back or the vehicle body behind the occupant on the rear side of the seat, and pull the pair of front-rear extending portions obliquely downward to the rear during the restraint.

4. The airbag device according to any one of Claims 1 to 3, wherein the airbag main body is formed such that the dimension in the seat left-right direction in the inflated and deployed state gradually decreases toward the lower end portion.

5. An inflater that generates gas during a vehicle collision; An airbag that is supplied with the gas and expands and deploys from the rear side to the front side of the seat above the vehicle seat; and includes The airbag A pair of left and right longitudinally extending portions that expand and deploy forward of the seat through both left and right sides of the head of an occupant seated on the vehicle seat, and a front-rear chamber having a connecting portion that connects the front end portions of the pair of longitudinally extending portions in the left-right direction of the seat. An airbag body that expands and deploys toward the occupant side behind the front-rear chamber on the rear side of the seat of the connecting portion. It has. The front-rear chamber is an airbag device formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat.

6. The airbag body is formed such that the dimension in the left-right direction of the seat in the inflated and deployed state is smaller on the front side of the seat than on the rear side of the seat. The airbag device according to claim 5, wherein the front portions of the pair of longitudinally extending portions are respectively sewn to the left and right side surfaces of the airbag body in the inflated and deployed state.

7. An inflater that generates gas during a vehicle collision. An airbag that is supplied with the gas and expands and deploys from the rear side of the seat to the front side of the upper part of the vehicle seat. It is provided with. The airbag is A pair of left and right longitudinally extending portions that expand and deploy forward of the seat through both left and right sides of the head of an occupant seated on the vehicle seat, and a front-rear chamber having a connecting portion that connects the front end portions of the pair of longitudinally extending portions in the left-right direction of the seat. An airbag body that expands and deploys toward the occupant side behind the front-rear chamber on the rear side of the seat of the connecting portion. It has. Before inflation and deployment, the airbag is an airbag device in which the front portion including the airbag body is respectively roll-folded from both outer sides in the left-right direction of the seat toward the center side in the left-right direction of the seat.

8. A vehicle seat on which an occupant is seated. The airbag device according to claim 1, claim 2, claim 3, claim 5, or claim 7 mounted on the rear side of the upper part of the vehicle seat. An occupant protection device provided with.

Images