Fuel vapor retention system and methods
Embodiments of the present invention relate to fuel tanks including features for capturing vapors displaced during a filling process. In an embodiment, the invention includes a fuel tank including a housing defining an interior volume; an inflow conduit providing fluid communication between the outside of the housing and the interior volume; a check-valve coupled to the inflow conduit, the check-valve configured to allow fuel to flow through the check-valve into the interior volume but prevent the flow of gases from the interior volume to the outside of the housing; an expansion member configured to reversibly change in volume; and a vent conduit providing fluid communication between the expansion member and the interior volume of the housing. Other embodiments are also described herein.
1. A vehicular fuel tank comprising:
a housing defining an interior volume;
an inflow conduit providing fluid communication between the outside of the housing and the interior volume;
a check-valve coupled to the inflow conduit, the check-valve configured to allow fuel to flow through the check-valve into the interior volume but prevent the flow of gases from the interior volume to the outside of the housing;
an expansion member configured to reversibly change in volume, the expansion member disposed outside of the housing;
a vent conduit providing fluid communication between the expansion member and the interior volume of the housing, the vent conduit passing through the inflow conduit and out of the housing to the expansion member;
a portion of the vent conduit disposed within the interior volume;
the portion of the vent conduit disposed within the interior volume comprising a first vent opening, the first vent opening facing in an opposite direction from the direction the vent conduit enters the interior volume to prevent liquid fuel from entering the vent conduit from the interior volume of the housing;
the vent conduit comprising a second vent opening disposed at or in the expansion member, the second vent opening facing in the same direction as the first vent opening, and the second vent opening in a plane above the first vent opening to prevent liquid fuel that has entered the vent conduit from entering the expansion member.
2. The vehicular fuel tank of claim 1 , the expansion member comprising an elastomeric composition.
3. The vehicular fuel tank of claim 1 , the expansion member comprising a polymer.
4. The vehicular fuel tank of claim 1 , the expansion member comprising a housing with pleated sides.
5. The vehicular fuel tank of claim 1 , the check-valve comprising a ball-valve.
6. The vehicular fuel tank of claim 1 , the housing comprising a substantially rigid material.
7. The vehicular fuel tank of claim 1 , the housing comprising a material selected from the group consisting of metals and polymers.
8. The vehicular fuel tank of claim 1 , the interior volume comprising between about 1 and about 40 gallons in volume.
9. The vehicular fuel tank of claim 1 , the fuel tank further comprising
a second housing defining a second interior volume, the expansion member disposed within the second interior volume; and
the second housing defining a breather port providing fluid communication between the outside of the fuel tank and the second interior volume.
10. The vehicular fuel tank of claim 1 , wherein the check valve is disposed adjacent the top of the housing.