Patent ID: 7556288

Claim:
A side-impact protective air bag for a motor vehicle extending across at least a part of the longitudinal extent of the vehicle, the air bag comprising two layers of fabric which are joined to each other to form the air bag, the air bag adapted to be located in a region of a roof frame of the vehicle when in a folded state, and in an unfolded state the air bag forms a side-impact curtain, the air bag connected to an inflation device which releases an inflating gas, wherein the air bag contains at least one primary chamber which can be inflated directly by gas from the inflation device, the air bag further comprising at least one pressure equalization chamber formed by a connection between the fabric layers of the air bag, the fabric layers being joined to each other across their entire surface at the pressure equalization chamber, wherein after inflation of the primary chamber, as a function of the pressure acting within the primary chamber, the inflating gas enters the pressure equalization chamber and inflates at least a portion of the pressure equalization chamber by separation of the connection between the fabric layers.