Fuel tank installation

1. A fuel tank installation, comprising a fuel tank with an expansion volume, a filler neck extending to the fuel tank for refueling said tank, a fill vent line in communication with the fuel tank for venting the fuel tank during refueling, an operating vent line for venting the expansion volume in the fuel tank and means for blocking the operating vent line including an electrically controllable valve, said electrically controllable valve being arranged in a penetration area in which the operating vent line extends through a wall portion of said tank and within a vent housing together with a float valve which opens or closes a communication path between the fill vent line and the fuel tank, said electrically operating valve being arranged in the communication path between the operating vent line and the fill vent line so as to open or close the communication path.

2. A fuel tank installation according to claim 1 , wherein a sensor is arranged in the area of the filler neck so as to sense the insertion of a refueling nozzle into the filler neck, said sensor, upon sensing the presence of a refueling nozzle in the filler neck providing a signal for actuating said electrically controllable valve, to close the communication path during refueling.

3. A fuel tank installation according to claim 1 , wherein said electrically controllable valve is arranged within said fuel tank.

4. A fuel tank installation according to claim 3 , wherein said tank includes expansion volumes and float valves are arranged within said expansion volumes within the fuel tank and an operating vent line extends from each float valve to an operating vent chamber in the vent housing.

5. A fuel tank installation according to claim 4 , wherein said operating vent chamber extends annularly around a fill vent chamber in the vent housing.