Air bag restraint including selectively operable venting elements

Abstract

An air bag safety system for cushioning restraint of a vehicle occupant during an impact event. The safety system includes a variable depth inflatable air bag cushion having at least one vent opening. A cover element of substantially pliable material is located in overlying relation to the vent opening. The cover element is selectively displaceable relative to the vent opening in response to the inflation depth of the air bag cushion so as to adjust venting characteristics.

1 . An air bag safety system for cushioning restraint of a vehicle occupant during an impact event, the safety system comprising: 
 a variable depth inflatable air bag cushion adapted to be selectively inflatable to one of a first depth or a second depth greater than the first depth wherein the air bag cushion includes at least one vent opening; and    a cover element of substantially pliable material disposed in overlying relation to the vent opening, the cover element including a blocking portion normally disposed in blocking relation across the vent opening and an aperture normally disposed within at least one folded pleat structure normally held in folded relation by at least one break-away seam disposed outboard of the vent opening, wherein the cover element is operatively connected to the air bag cushion such that upon inflation of the air bag cushion to said first depth the blocking portion and the pleat structure remain in their normal positions and such that upon inflation of the air bag cushion to said second depth the cover element is placed into tension thereby pulling the blocking portion away from the vent opening while at least partially collapsing the pleat structure such that the aperture is moved into alignment over the vent opening so as to increase venting across the air bag cushion.