Passenger seat air bag

Abstract

A passenger seat air bag has a bottom wall portion having an aperture portion for inflating gas inlet, and a ceiling wall portion. The air bag is shaped into a bag in which outer circumferential edges of the bottom wall portion and the ceiling wall portion are coupled with each other. At the beginning of folding, while the state where the bottom wall portion and the ceiling wall portion are put on top of each other and unfolded to be flat is kept, a coupling portion on the vehicle front side where the outer circumferential edges of the bottom wall portion and the ceiling wall portion are coupled with each other is shifted toward the vehicle rear side. In that state, the air bag is folded and received in a portion of an instrument panel so that the circumferential edges thereof are close to the aperture portion. In another air bag, a flow control cloth is disposed inside an air bag body so as to cover the gas inlet and change the flow of inflating gas flowing in through the gas inlet. The flow control cloth is disposed to cover the gas inlet in the left/right direction of a vehicle, and arranged so that the flow rate of inflating gas flowing toward the front side of a substantially middle portion in the front/rear direction of the flow control cloth is made higher than the flow rate of inflating gas flowing toward the rear side thereof.

What is claimed is:  
     
         1 . A passenger seat air bag comprising: 
 a bottom wall portion having an aperture portion for inflating gas inlet provided substantially at a center thereof; and    a ceiling wall portion having an outer shape substantially the same as that of said bottom wall portion and disposed in opposition to said bottom wall portion, respective outer circumferential edges of said bottom and ceiling wall portions being coupled with each other so as to form a bag,    wherein said air bag is folded in a state where said bottom wall portion and said ceiling wall portion are put on top of each other so that said air bag is unfolded to be flat, said folded air bag being received in a portion of an instrument panel so that said circumferential edges are made close to said aperture portion,    wherein at the beginning of folding, while the state where said bottom wall portion and said ceiling wall portion are put on top of each other so that said air bag is unfolded to be flat is kept, a coupling portion on the vehicle front side where said bottom wall portion and said ceiling wall portion are coupled with each other is shifted toward the vehicle rear side, and said air bag is folded and received in this state so that said circumferential edges are made close to said aperture portion.    
     
     
         2 . A passenger seat air bag comprising: 
 a bottom wall portion having an aperture portion for inflating gas inlet provided substantially at a center thereof; and    a ceiling wall portion having an outer shape substantially the same as that of said bottom wall portion and disposed in opposition to said bottom wall portion, respective outer circumferential edges of said bottom and ceiling wall portions being coupled with each other so as to form a bag,    wherein said air bag is folded in a state where said bottom wall portion and said ceiling wall portion are put on top of each other so that said air bag is unfolded to be flat, said folded air bag being received in a portion of an instrument panel so that said circumferential edges are made close to said aperture portion,    wherein said air bag further comprises a band-like tether for generating tension in said air bag at the time of inflating so as to restrain a shape of said air bag upon completion of an inflating, said tether being disposed in said air bag in a manner so that one end portion of said tether is coupled with a rear edge of said bottom wall portion on a vehicle rear side in a circumferential edge of said aperture portion, while the other end portion of said tether is coupled with a position on a vehicle front side of a center vicinity of said ceiling wall portion.    
     
     
         3 . A passenger seat air bag used in a passenger seat air bag system disposed on a top surface of an instrument panel in front of a passenger seat in a vehicle, said air bag comprising: 
 an air bag main body;    a gas inlet disposed substantially along a horizontal plane of said air bag main body; and    a flow control cloth provided inside said air bag main body to cover said gas inlet for changing a flow of inflating gas allowed to flow in through said gas inlet,    wherein said flow control cloth is disposed so as not only to cover said gas inlet in a left and right direction of said vehicle but also to make a flow rate of said inflating gas flowing toward a rear side higher than a flow rate of said inflating gas flowing toward a front side with respect to a substantially middle portion in a front and rear direction of said flow control cloth.    
     
     
         4 . A passenger seat air bag according to  claim 3 , wherein, in order to make said flow rate of said inflating gas flowing toward said front side lower than said flow rate of said inflating gas flowing toward said rear side thereof with respect to said substantially middle portion in said front/rear direction of said flow control cloth, 
 said flow control cloth is disposed so that left and right edges of said flow control cloth are coupled with a circumferential edge of said gas inlet in an inner circumferential surface of said air bag body while front and rear edges of said flow control cloth are not coupled with said air bag body, and    gas communication holes for allowing said inflating gas to pass therethrough are disposed in said left and right sides of said rear edge of said flow control cloth.    
     
     
         5 . A passenger seat air bag according to  claim 3 , wherein, in order to make said flow rate of said inflating gas flowing toward said front side lower than said flow rate of said inflating gas flowing toward said rear side thereof with respect to said substantially middle portion in said front/rear direction of said flow control cloth, 
 said flow control cloth is disposed so that left and right edges and a front edge of said flow control cloth are coupled with a circumferential edge of said gas inlet in an inner circumferential surface of said air bag body while a rear edge of said flow control cloth is not coupled with said air bag body, and    gas communication holes for allowing said inflating gas to pass therethrough are disposed, respectively, between each of said left and right edges of said flow control cloth near said front edge and said air bag body or in vicinities of left and right sides near said front edge of said flow control cloth itself.    
     
     
         6 . A passenger seat air bag according to  claim 3 , wherein said rear edge of said flow control cloth is connected, through a connecting belt, with a rear edge of said circumferential edge of said gas inlet in said air bag body so that forward movement of said inflating gas can be restricted when said inflating gas flows in through said gas inlet.