Fuel tank ventilation/air supply system for motor vehicles ha two anti-parallel valves, one a ventilation valve with gravity-operated closure ball

摘要

The device has a connection pipe between fuel tank and active carbon filter, and two anti-parallel valves (3,4). One valve (3) is mainly for ventilation, and has a gravity-operated ball (7) held in a conical funnel, to act as closure element. The ball has a jacket of sound-absorbent material. The second valve (4) is for air supply and has an elastic membrane (13), pressed pre-tensioned against a valve seat, to act as valve body (12). The valves may be integrated in the connection pipe or the fuel tank.