US Patent 9890747 Tank pressure control solenoid with passive tank vacuum

A valve assembly providing flow control between a fuel tank and a carbon canister, which includes two valves providing two different flow paths, where the first valve provides active vacuum relief along the first flow path, and the second valve provides passive vacuum relief along the second flow path. A reservoir is added to the cap which is common for both flow paths. The second valve has a sealing valve member and a biasable member that passively relieves fuel tank vacuum pressure at a predetermined vacuum level.