VENT INCLUDING A SEPARATOR MEMBRANE

Abstract

A vent structure at least partially defining a passageway between the inside of a fuel storage tank and the outside atmosphere includes a separator membrane. The separator membrane is positioned within the vent structure configured to block liquid fuel in the storage tank from reaching the outside atmosphere through the passageway. The separator membrane is permeable by air. The vent structure may be in the form of a cap or a remote vent, or it may be provided substantially within the fuel storage tank. The vent structure may be provided as part of a fuel evaporative emissions system for a vehicle or motor-driven power equipment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a fuel storage system having a vented membrane cap;

FIG. 2 is an exploded assembly view of the vented membrane cap of FIG. 1;

FIG. 3 is perspective view of the vented membrane cap of FIG. 1;

FIG. 4 is a cross-sectional view of the vented membrane cap of FIG. 1, taken along line 4-4 of FIG. 3;

FIG. 5 is an exploded assembly view of a vented membrane cap according to another embodiment of the invention;

FIG. 6 is a schematic view of a fuel storage system including the vented membrane cap of FIG. 5;

FIG. 7 is an exploded assembly view of a remote vent according to another embodiment of the invention;

FIG. 8 is a cross-sectional view of the remote vent of FIG. 7;

FIG. 9 is a schematic view of a fuel storage system including the remote vent of FIG. 7;

FIG. 10 is a schematic view of a fuel storage system including a bottom-vented membrane-separated vent head according to another embodiment of the invention; and

FIG. 11 is a schematic view of a fuel storage system including a membrane-capped vent tube positioned within a storage tank volume according to yet another embodiment of the invention.

Claims

1. A fuel evaporative emissions system for a vehicle or motor-driven power equipment comprising a storage tank for holding a volume of fuel;a vent structure at least partially defining a passageway between the inside of the storage tank and the outside atmosphere; anda separator membrane positioned within the vent structure configured to block liquid fuel in the storage tank from reaching the outside atmosphere through the passageway, the separator membrane being permeable by air;wherein the vent structure includes at least one of a cap, and a storage tank.

2. The fuel evaporative emissions system of claim 1, wherein the vent structure includes a cap configured to close an opening of the storage tank, the cap having a main body with a vent aperture formed therein.

3. The fuel evaporative emissions system of claim 2, wherein the cap includes a cover coupled to the main body and at least partially defining a chamber in communication with the vent aperture in which the separator membrane is mounted.

4. The fuel evaporative emissions system of claim 3, wherein the main body is formed with an annular will extending into the chamber, the separator membrane being boned to the annular wall.

5. The fuel evaporative emissions system of claim 4, wherein the separator membrane includes a peripheral rim that is welded to the annular wall.

6. The fuel evaporative emissions system of claim 1, further comprising a carbon canister between the vent structure and the outside atmosphere along the passageway for removing selected components of fuel vapor existing the storage tank.

7. The fuel evaporative emissions system of claim 1, wherein the separator membrane substantially blocks fuel vapors from reaching the outside atmosphere through the passageway.

8. The fuel evaporative emissions system of claim 7, wherein the separator membrane is in direct contact with the outside atmosphere.

9. A vent structure for a fuel system comprising: a housing at least partially defining a chamber; anda separator membrane positioned within the chamber, the separator membrane being impermeable to liquid and permeable to select gases;wherein the separator membrane includes a peripheral rim, said rim being bonded to the housing.

10. The vent structure of claim 9, wherein the housing is part of a fuel cap configured to close an opening of a fuel containment structure of the fuel system.

11. The vent structure of claim 10, wherein the fuel cap includes a first end configured to mate with the opening and a second end opposite the first end, a cover member being attached to the fuel cap at the second end, wherein the cover member is formed with an opening in communication with the chamber and the separator membrane.

12. The vent structure of claim 11, further comprising a hose coupled to the opening in the cover member and having a remote end positioned at a remote location from the fuel cap.

13. The vent structure of claim 12, further comprising an air filer positioned adjacent the remote location.

14. The vent structure of claim 12, further comprising a carbon canister coupled to the remote end of the hose.

15. The vent structure of claim 9, wherein the rim of the separator membrane is welded to the housing.

16. The vent structure of claim 9, wherein the housing is part of a remote vent that is coupled to a fuel containment structure of the fuel system.

17. A fuel cap configured for attachment to a fuel containment structure of a vehicle or other motor-driven power equipment comprising: a main body portion having a vent aperture formed therein;a chamber at least partially defined by the main body portion;an external opening in communication with the chamber and with a surrounding atmosphere; anda separator membrane positioned within the chamber, the separator membrane being primarily constructed of a material that blocks liquid fuel within the fuel containment structure from reaching the external opening and that allows air to flow into and out of the fuel containment structure as necessary to avoid substantial deviation from atmosphere pressure within the fuel containment structure.

18. The fuel cap of claim 17, wherein the separator membrane is primarily constructed of a material that substantially blocks the passage of hydrocarbon fuel vapor from the fuel containment structure to the surrounding atmosphere.

19. The fuel cap of claim 18, wherein the fuel cap is configured to substantially eliminate the emission of hydrocarbon fuel vapor from within the fuel containment structure without the use of a carbon canister.

20. The fuel of claim 17, wherein the external opening is in communication with the surrounding atmosphere with a carbon canister therebetween.