Active bolster with active vent for load management

Abstract

An active bolster has a plastic-molded, expandable front wall and a plastic-molded back wall joined around a substantially sealed perimeter with the front wall to form an inflatable bladder. The back wall includes at least one active vent and at least one substantially circumferential pleated baffle. An inflator couples an inflation gas into the inflatable bladder in response to a crash event of the vehicle. The active vent comprises a window opening in the back wall and an integrally-molded flap juxtaposed to the window opening. The flap has an undeflected position corresponding to a first flow coefficient and a deflected position corresponding to a second, nonzero flow coefficient that is less than the first flow coefficient. The flap moves from the undeflected position to the deflected position when a pressure in the inflatable bladder resulting from a passenger impact is greater than a predetermined pressure.