Patent ID: 7896022

Claim:
An on-board refueling vapor recovery system, comprising: a fuel tank; a canister; a filler cup having a mechanical seal disposed therein forming a seal around a filler nozzle during refueling; a rollover valve; a vent line connecting the canister and the filler cup; a shutoff mechanism that closes a first vapor path between the fuel tank and the filler cup when liquid fuel in the tank reaches a predetermined level and that closes a second vapor path between the canister and the filler cup, wherein vapor flows in an unrestricted manner from the tank to the filler cup along the first vapor path during refueling to recirculate the vapor, wherein vapor flows from the canister to the filler cup along the second vapor path during refueling, wherein closure of the first vapor path and the second vapor path reduces pressure in the filler cup to create a vacuum force below the mechanical seal and induce shutoff of a fuel nozzle, and wherein the shutoff mechanism closes the first vapor path and the second vapor path substantially simultaneously.