Gas generator

Abstract

A gas generator ( 1 A) includes a housing including a lower shell ( 10 ) and an upper shell ( 20 ), an igniter ( 40 ), a gas generating agent ( 61 ), and a filter ( 70 ). The housing includes a bottom plate portion ( 11 ) to which the igniter ( 40 ) is assembled and a combustion chamber ( 60 ) accommodating the gas generating agent ( 61 ). The filter ( 70 ) is formed from a hollow cylindrical member and disposed in the housing so as to surround the combustion chamber ( 60 ) in a radial direction of the housing. The bottom plate portion ( 11 ) is provided with a positioning portion ( 38 ) formed from a resin-molded portion secured to the bottom plate portion ( 11 ), which is formed by adhering a fluid resin material to an inner surface and solidifying the same, and the positioning portion ( 38 ) abuts to an inner circumferential surface of an axial end portion of the filter ( 70 ) located on a side of the bottom plate portion ( 11 ).

1 . A gas generator, comprising:
 a short cylindrical housing which is constituted of a top plate portion ( 21 ) and a bottom plate portion ( 11 ) closing axial end portions and a circumferential wall portion ( 12 ,  22 ) provided with a gas discharge opening ( 23 ) and includes therein a combustion chamber ( 60 ) accommodating a gas generating agent ( 61 );   an igniter ( 40 ) assembled to said bottom plate portion ( 11 ), for burning said gas generating agent ( 61 );   a hollow cylindrical filter ( 70 ) disposed in said housing and surrounding said combustion chamber ( 60 ) in a radial direction of said housing,
 said housing at least having a lower shell ( 10 ) including said bottom plate portion ( 11 ) and an upper shell ( 20 ) including said top plate portion ( 21 ); and 
   a positioning portion ( 38 ) formed from a resin-molded portion which is formed by attaching a fluid resin material to an inner surface of said lower shell ( 10 ) and solidifying the fluid resin material so that at least a part of the resin-molded portion is secured to said lower shell ( 10 ), for positioning said filter ( 70 ) in a radial direction by abutting to at least one of an inner circumferential surface and an outer circumferential surface of an axial end portion of said filter ( 70 ) located on a side of said bottom plate portion ( 11 ).   
     
     
         2 . The gas generator according to  claim 1 , wherein
 said positioning portion ( 38 ) has an annular shape abutting to said filter ( 70 ) along a circumferential direction of said filter ( 70 ).   
     
     
         3 . The gas generator according to  claim 1 , wherein
 a plurality of said positioning portions ( 38 ) are arranged as aligned along a circumferential direction of said filter ( 70 ).   
     
     
         4 . The gas generator according to  claim 1 , wherein
 said positioning portion ( 38 ) is located on said bottom plate portion ( 11 ) in a portion facing said combustion chamber ( 60 ) and abuts only to the inner circumferential surface of the axial end portion of said filter ( 70 ) located on the side of said bottom plate portion ( 11 ).   
     
     
         5 . A gas generator, comprising:
 a short cylindrical housing which is constituted of a top plate portion ( 21 ) and a bottom plate portion ( 11 ) closing axial end portions and a circumferential wall portion ( 12 ,  22 ) provided with a gas discharge opening ( 23 ) and includes therein a combustion chamber ( 60 ) accommodating a gas generating agent ( 61 );   an igniter ( 40 ) assembled to said bottom plate portion ( 11 ), for burning said gas generating agent ( 61 );   a hollow cylindrical filter ( 70 ) disposed in said housing and surrounding said combustion chamber ( 60 ) in a radial direction of said housing; and   a holding portion ( 30 ) provided on said bottom plate portion ( 11 ), for holding said igniter ( 40 ),   said housing at least having a lower shell ( 10 ) including said bottom plate portion ( 11 ) and an upper shell ( 20 ) including said top plate portion ( 21 ),   said lower shell ( 10 ) including a protruding cylindrical portion ( 17 ) provided to protrude toward said top plate portion ( 21 ) and an opening ( 15 ) provided at an axial end portion of said protruding cylindrical portion ( 17 ), which is located on a side of said top plate portion ( 21 ),   said holding portion ( 30 ) including a holding portion main body formed from a resin-molded portion which is formed by attaching a fluid resin material to said bottom plate portion ( 11 ) so as to at least reach a part of an outer surface of said bottom plate portion ( 11 ) from a part of an inner surface of said bottom plate portion ( 11 ) through said opening ( 15 ) and solidifying the fluid resin material so that at least a part of the resin-molded portion is secured to said bottom plate portion ( 11 ), for holding said igniter ( 40 ), an extended portion extending outward from said holding portion main body along the inner surface of said bottom plate portion ( 11 ), and a positioning portion ( 38 ) provided in said extended portion, for positioning said filter ( 70 ) in a radial direction by abutting to at least one of an inner circumferential surface and an outer circumferential surface of an axial end portion of said filter ( 70 ) located on a side of said bottom plate portion ( 11 ).   
     
     
         6 . The gas generator according to  claim 5 , wherein
 said extended portion is secured to said bottom plate portion ( 11 ).   
     
     
         7 . The gas generator according to  claim 5 , wherein
 said positioning portion ( 38 ) has an annular shape abutting to said filter ( 70 ) along a circumferential direction of said filter ( 70 ).   
     
     
         8 . The gas generator according to  claim 5 , wherein
 a plurality of said positioning portions ( 38 ) are arranged as aligned along a circumferential direction of said filter ( 70 ).   
     
     
         9 . The gas generator according to  claim 5 , wherein
 said positioning portion ( 38 ) is located on said bottom plate portion ( 11 ) in a portion facing said combustion chamber ( 60 ) and abuts only to the inner circumferential surface of the axial end portion of said filter ( 70 ) located on the side of said bottom plate portion ( 11 ).