Patent ID: 6990961

Claim:
A ventilation and aeration system for a fuel tank of a motor vehicle comprising: a) a ventilation line ( 9 ) mounted on an upper wall of the fuel tank to provide connection between the exterior and the interior volume of the tank: b) a ventilation link ( 13 ) connected to the ventilation line ( 9 ) and extending downwardly into the tank, the link having; i) a ventilation opening ( 16 ) of a first through-flow cross section in the ventilation link ( 13 ) at or near the end thereof which is further from the upper wall of the tank, and ii) an aeration opening ( 21 ) of a second through-flow cross section in the ventilation link ( 13 ) at a location which is nearer to the upper wall of the tank than is the ventilation opening ( 16 ), wherein the aeration opening ( 21 ) is sufficiently smaller than the ventilation opening ( 16 ) that gas pressure increases in the volume of the tank above the fuel level as the tank is filled, to thereby cause fueling to stop; and c) a single roll-over valve ( 10 ) having a non-buoyant blocking element 12 located nearer to the tank upper wall than both the ventilation and the aeration openings to block the connection between the ventilation link and the ventilation line when the tank is inverted.