An air bag is formed of a panel and a guide member fixed between two side portions of the panel. The guide member may be formed of first piece extending diagonally upwardly from a lower end near an opening of the panel to form an upper chamber, and a second piece extending diagonally downwardly from...http://www.google.es/patents/US5593179?utm_source=gb-gplus-sharePatente US5593179 - Air bag device for vehicle
