Air bag system for vehicle

Abstract

The present invention preferably regulates discharge rate of the gas filling the air bag body from the vent hole provided in the air bag body. There is provided a bend section for applying tensile-force onto the pair of the faces to pull the faces in the longitudinal direction apart from the vent hole. When predetermined tensile-force is applied onto the pair of the faces, the faces become closed and sealed. Meanwhile, when smaller tensile-force than the predetermined tensile-force is applied, the pair of the faces become apart from each other and opened, so that the gas is discharged from this opening of the faces.

1 . An air bag system for a vehicle comprising an air bag body formed by stitching base fabric material, an inflator that charges the air bag body with gas, and a vent hole that is a through hole provided in the air bag body so as to communicate the inside with the outside of the air bag body,
 wherein   the vent hole of the air bag body is formed to be longer in a longitudinal direction thereof, and   the air bag body comprises:   a tensile-force applying means that applies tensile-force in the longitudinal direction of the vent hole;   a pair of faces provided along the gas discharge direction from the vent hole; and   a flow-passage restriction membrane provided along the longitudinal direction of the vent hole.   
   
   
       2 . The air bag system for a vehicle according to the  claim 1 , wherein
 the air bag body is constituted by plural basic fabric pieces, and   the vent hole is provided in a stitched section where at least two pieces of the plural basic fabric pieces are stitched, and   the stitched section comprises a neck portion that is set in a direction from the outside toward the inside of the air bag body, so that, when the air bag body is inflated and expanded, an outer circumferential length passing through a longitudinal end of the vent hole of the air bag body is locally reduced so as to be shorter than an outer circumferential length extending outer side from the vent hole.   
   
   
       3 . The air bag system for a vehicle according to the  claim 1 , wherein
 the air bag body is constituted by plural basic fabric pieces,   the vent hole is provided in a stitched section where at least two pieces of the plural basic fabric pieces are stitched,   the stitched section comprises a bend section recessed in curve toward the inside of the air bag body, so that, when the air bag body is inflated and expanded, an outer circumferential length passing through a longitudinal end of the vent hole of the air bag body is locally reduced so as to be shorter than an outer circumferential length extending outer side from the vent hole, and an end-support that supports both side ends of the faces, and   the bend section comprises the tensile-force applying means.   
   
   
       4 . The air bag system for a vehicle according to the  claim 1 , wherein the tensile-force applying means is provided in the vicinity of the longitudinal ends of the vent hole, and comprises at least one strap member for reducing an outer circumferential length of the air bag body passing through a longitudinal end of the vent hole. 
   
   
       5 . The air bag system for a vehicle according to the  claim 1 , wherein the pair of the faces are formed in an asymmetrical shape. 
   
   
       6 . The air bag system for a vehicle according to the  claim 2 , wherein the pair of the faces are formed in an asymmetrical shape. 
   
   
       7 . The air bag system for a vehicle according to the  claim 3 , wherein the pair of the faces are formed in an asymmetrical shape. 
   
   
       8 . The air bag system for a vehicle according to the  claim 1 , wherein the flow-passage restriction membrane is provided inside the air bag body. 
   
   
       9 . The air bag system for a vehicle according to the  claim 2 , wherein the flow-passage restriction membrane is provided inside the air bag body. 
   
   
       10 . The air bag system for a vehicle according to the  claim 3 , wherein the flow-passage restriction membrane is provided inside the air bag body. 
   
   
       11 . The air bag system for a vehicle according to the  claim 1 , wherein the longitudinal direction of the vent hole extends from the upper front side to the lower rear side of the vehicle. 
   
   
       12 . The air bag system for a vehicle according to the  claim 2 , wherein the longitudinal direction of the vent hole extends from the upper front side to the lower rear side of the vehicle. 
   
   
       13 . The air bag system for a vehicle according to the  claim 3 , wherein the longitudinal direction of the vent hole extends from the upper front side to the lower rear side of the vehicle. 
   
   
       14 . An air bag system for a vehicle comprising:
 an air bag body formed in a bag form, an inflator that charges the air bag body with gas and a vent hole provided in the air bag body so as to discharge the gas filling the air bag body,   wherein   the air bag body comprises:   a pair of faces that are provided around the vent hole to form the vent hole in a slit-like shape extending in one direction; and   a tensile-force applying section that applies tensile-force onto the pair of the faces in the longitudinal direction apart from the vent hole, and   the pair of the faces becomes closed and sealed when the tensile-force applying section applies predetermined tensile-force onto the pair of the faces, and the pair of the faces become apart from each other and opened when the tensile-force applying section applies smaller tensile-force than the predetermined tensile-force onto the pair of the faces, so that the gas filling the air bag body is discharged from the opening of the pair of the faces.   
   
   
       15 . An air bag system for a vehicle comprising:
 an air bag formed by stitching basic fabric material,   an inflator that charges the air bag body with gas, and   a vent hole that is a through hole provided in the air bag body so as to communicate the inside with the outside of the air bag body,   wherein   the vent hole for discharging the gas filling the air bag body is formed to be a long slit along the direction to restrict the expansion of the air bag.