Patent ID: 9694310
Date: 2017-07-04
CPC Classifications: B01D,F02M

Claim:
1. A fuel vapor recovery canister adapted for use in a vehicle fuel system, the fuel vapor recovery canister comprising a filter bed housing formed to include an interior region, a canister inlet opening into an upstream portion of the interior region, and a canister outlet opening into a downstream portion of the interior region and communicating with atmosphere, a hydrocarbon filter located in the interior region of the filter bed housing, the hydrocarbon filter including a first carbon bed positioned to lie in fluid communication with any pressurized fuel vapor and vacuum extant in the upstream portion of the interior region and a second carbon bed positioned to lie in fluid communication with any atmosphere extant in the downstream portion of the interior region and in spaced-apart relation to the first carbon bed, and a vapor flow controller configured to direct flow of at least some fuel vapor moving through the fuel vapor recovery canister from the first carbon bed to pass along a first flow path to atmosphere without passing through the second carbon bed during refueling of a vehicle fuel system associated with the fuel vapor recovery canister so that the second carbon bed remains substantially clean for use during normal operation of the vehicle fuel system and for directing the movement of fuel vapor from the first carbon bed to pass along a second flow path to atmosphere after passing through the second carbon bed during normal operation of the vehicle fuel system so that hydrocarbons suspended in fuel vapor passing through the fuel vapor recovery canister can be adsorbed by carbon in the second carbon bed and removed from vapor discharged from the fuel vapor recovery canister during normal operation the vehicle fuel system providing a low level of hydrocarbon discharge to atmosphere during normal operation, wherein the vapor flow controller includes a bypass valve configured to move from a normally closed position to an opened position in response to (i) a fuel tank closure associated with the fuel vapor recovery canister being opened by a user removing a fuel cap and (ii) pressure in a fuel tank associated with the fuel vapor recovery canister being above atmospheric pressure.