Air bag module with vent cover

Abstract

A vehicle occupant protection apparatus ( 10 ) comprises an inflatable device ( 12 ) for helping to protect a vehicle occupant, and an inflator ( 14 ). The inflator ( 14 ) has a cylindrical configuration and a plurality of inflation fluid outlets ( 24 ). A vent member ( 30 ) connected with the inflator ( 14 ) has an annular vent wall ( 60 ) having at least one vent opening ( 62 ). A vent cover ( 100 ) has a closed condition clamped on the vent wall ( 60 ) and covering the vent opening ( 62 ), and an open condition removed at least partially from the vent wall and enabling fluid flow through the vent opening. An actuatable device ( 130 ) on the vent cover ( 100 ) has an unactuated condition maintaining the vent cover in the closed condition, and an actuated condition releasing the vent cover for movement to the open condition to vent inflation fluid from the apparatus ( 10 ).

Having described the invention, we claim:  
     
         1 . A vehicle occupant protection apparatus comprising: 
 an inflatable vehicle occupant protection device for, when inflated, helping to protect the vehicle occupant;    an inflator for providing inflation fluid for inflating said protection device, said inflator having a generally cylindrical configuration and having a plurality of inflation fluid outlets;    a vent member connected with said inflator and having an annular vent wall having at least one vent opening;    a vent cover having a closed condition clamped on said vent wall and covering said vent opening, said vent cover having an open condition removed at least partially from said vent wall and enabling fluid flow through said vent opening to vent inflation fluid from said apparatus; and    an actuatable device on said vent cover, said actuatable device having an unactuated condition maintaining said vent cover in the closed condition on said vent wall, said actuatable device having an actuated condition releasing said vent cover for movement from the closed condition to the open condition to enable fluid flow through said vent opening to vent inflation fluid from said apparatus.    
     
     
         2 . An apparatus as set forth in  claim 1  wherein said actuatable device comprises an explosive bolt.  
     
     
         3 . An apparatus as set forth in  claim 1  wherein said vent cover has a cylindrical configuration.  
     
     
         4 . An apparatus as set forth in  claim 1  wherein said vent cover is formed as a split ring and has a cylindrical outer wall.  
     
     
         5 . An apparatus as set forth in  claim 4  wherein said outer wall of said vent cover has first and second end portions, a first mounting flange is disposed on said first end portion of said outer wall, and a second mounting flange is disposed on said second end portion of said outer wall.  
     
     
         6 . An apparatus as set forth in  claim 5  wherein said first and second mounting flanges extend parallel to each other and overlie each other when said vent cover is in the closed condition to clamp said vent cover on said vent wall, and wherein said actuatable device extends through said first and second mounting flanges.  
     
     
         7 . An apparatus as set forth in  claim 1  further comprising a retainer having an annular, radially extending main body portion for clamping said protection device to said vent member, said retainer having a plurality of axially extending, circumferentially spaced clamping legs for clamping said inflator to said vent member at a location radially between said inflation fluid outlets of said inflator and said vent opening; 
 said circumferentially spaced clamping legs of said retainer defining between them a plurality of circumferentially spaced fluid passages that provide fluid communication between said inflation fluid outlets of said inflator and said vent opening in said reaction plate.  
 
     
     
         8 . An apparatus as set forth in  claim 7  wherein said vent member comprises a reaction member for supporting said apparatus on the vehicle.  
     
     
         9 . An apparatus as set forth in  claim 1  wherein said vent member comprises a reaction member for supporting said apparatus on the vehicle.  
     
     
         10 . A vehicle occupant protection apparatus comprising: 
 an inflatable vehicle occupant protection device for, when inflated, helping to protect the vehicle occupant;    an inflator for providing inflation fluid for inflating said protection device, said inflator having a generally cylindrical configuration centered on an axis and having a plurality of inflation fluid outlets for directing inflation fluid to flow radially outward from said inflator;    a reaction plate for supporting said inflator and said protection device on the vehicle, said reaction plate having at least one vent opening disposed radially outward of said inflation fluid outlets of said inflator;    a retainer having an annular, radially extending main body portion for clamping said protection device to said reaction plate and having a plurality of axially extending, circumferentially spaced clamping legs for clamping said inflator to said reaction plate at a location radially between said inflation fluid outlets of said inflator and said vent opening of said reaction plate;    said circumferentially spaced clamping legs of said retainer defining between them a plurality of circumferentially spaced fluid passages that provide fluid communication between said inflation fluid outlets of said inflator and said vent opening in said reaction plate;    a vent cover having a closed condition clamped on said reaction plate and covering said vent opening; and    an actuatable device on said vent cover, said actuatable device having an unactuated condition maintaining said vent cover in the closed condition clamped on said reaction plate, said actuatable device having an actuated condition releasing said vent cover for movement from the closed condition to an open condition removed at least partially from said reaction plate and enabling fluid flow through said vent opening to vent inflation fluid from said apparatus.    
     
     
         11 . An apparatus as set forth in  claim 10  wherein said reaction plate has a cylindrical vent wall in which said vent opening is formed, said vent cover having a cylindrical portion covering said vent opening in said cylindrical vent wall.  
     
     
         12 . An apparatus as set forth in  claim 11  wherein said cylindrical vent wall depends from a planar central portion of said reaction plate.