Claims
- 1. A vent valve for use in controlling discharge of fuel vapor from a fuel tank, comprising:
a housing for attachment to a fuel tank; a wall of the housing defining a cavity; a float contained in the housing; the float being responsive to a level of liquid in the fuel tank; the housing having a passage therein communicating with an external portion of the tank; at least one vent positioned proximate to and communicating with the passage; a flexible diaphragm attached to at least the float; the diaphragm being a generally circular diaphragm, generally concentric with the passage in the housing; a generally annular outer edge of the diaphragm being attached to the float; an annular portion of the flexible diaphragm, spaced generally radially inwardly of the outer edge of the diaphragm being displaceably positioned least proximate to the passage to control the flow of vapor through the vent and through the passage; movement of the float toward the passage causing a portion of the flexible diaphragm to contact a surface of the housing at least proximate to the passage and the vent to prevent the flow of fuel vapor through the passage and vent; and movement of the float away from the passage causing the flexible diaphragm to move out of contract with the surface of the housing permitting passage of fuel vapor through the vent and passage.
- 2. A vent valve in claim 1, further comprising:
an aperture extending through a portion of the diaphragm; the aperture communicating with the vents; and a protrusion carried on the float proximate to the aperture in the diaphragm for abutting and closing the aperture.
- 3. The vent valve in claim 2, further comprising:
a flexible diaphragm having a first side, at least a portion of the first side displaceably abutting a surface of the housing; a second side of the diaphragm generally opposite the first side of the diaphragm, the second side generally facing at least a portion of the float; a bore extending through at least one of the diaphragm and float; and the bore communicating with the cavity of the housing and with a gap between the second side of the flexible diaphragm and the float.
- 4. The vent valve in claim 1, further comprising:
the diaphragm being formed as a convoluted structure having a generally annular extending portions extending toward the passage; the extending portion being spaced generally radially from the passage for abutting a corresponding surface of the housing proximate the passage; and the extending portion providing an annular seal proximate to and spaced from the passage.
- 5. The vent valve in claim 1, further comprising:
the at least one vent being formed in the portion of the housing proximate to the passage; the at least one vent formed in the housing communicating with the passage; the at least one vent formed in the housing communicating with the cavity of the housing when the diaphragm is displaced away from the vent; the diaphragm abutting the surface of the housing proximate to the passage and covering at least a portion of the vent when the float is moved toward the passage; and the diaphragm being progressively displaced away from abutment with the inside surface of the housing in response to displacement of the float away from the passage.
- 6. The vent valve of claim 5, further comprising:
the at least one vent being positioned at least generally radially extending from the perimeter of the passage.
- 7. The vent valve of claim 5, further comprising:
the at least one vent generally tapering along at least one dimension spaced from the passage.
- 8. The vent valve of claim 1, further comprising:
a flexible diaphragm having a first side, a portion of the first side displaceably abutting the surface of the housing; a second side of the diaphragm which generally opposite the first side of the diaphragm, the second side generally facing at least a portion of the float; a bore extending through at least one of the diaphragm and float; the bore communicating with the cavity of the housing and with a gap between the second side of the flexible diaphragm and the float; a protrusion extending from first side of the diaphragm for engagement in the passage; and engagement of the protrusion in the passage restricting flow of fuel vapor through the passage.
- 9. The vent valve of claim 8, further comprising:
vent at least one defined in the portion of the housing proximate to the passage; the vents communicating with the passage; the vents communicating with the cavity of the housing when the diaphragm is at least partially displaced from the vents; and wherein the protrusion engages the passage when the float is positioned towards the passage, engagement of the protrusion in the passage restricting flow of fuel vapor through the passage, the flexible diaphragm covering an end of the at least one vent when the float is positioned towards the passage, covering of the vents by the diaphragm preventing passage of vapor through the vent to the passage, displacement of the diaphragm from the vent permitting initial venting of fuel vapors through the vent to the passage.
- 10. The vent valve of claim 9, further comprising:
a guide protrusion extending from the second side of the diaphragm; a guide recess defined in the float generally opposite the guide protrusion for receiving the guide protrusion therein; and engagement of the guide protrusion in the guide recess providing guidance and alignment of movement of the diaphragm relative to the passage and housing.
- 11. The vent valve of claim 1, further comprising:
a generally tubular wall defining the passage; the at least one vent being defined in the wall providing communication between the cavity of the housing and the passage; the flexible diaphragm being positioned generally against an outside surface of the wall; and the flexible diaphragm being displaceably positioned over the vent.
- 12. The vent valve in claim 11, further comprising:
the flexible diaphragm being positioned and retained between the float and an outside surface of the wall; movement of the float on an increasing level of fuel in the tank causing the flexible diaphragm attached to the float and the outside surface of the wall to displaceably cover the vents; and movement of the float on a decreasing level of fuel in the tank causing the flexible diaphragm to displaceably uncover the vent.
- 13. The vent valve of claim 12, further comprising:
a second flexible diaphragm retained between the float and the outside surface of the wall; and the second diaphragm being spaced from the first diaphragm and the vent.
- 14. The vent valve of claim 12, further comprising:
a second diaphragm positioned between and attached to an outside surface of the float and a corresponding inside surface of the housing.
- 15. The vent valve of claim 11, further comprising:
the flexible diaphragm being retained on an upper portion of the float and attaching to an outside surface of the wall defining the passage; a rim attached to the float proximate to the diaphragm, the rim being spaced from the outside surface of the wall with the diaphragm extending between the rim and the wall, the rim facilitating controlled movement and retention of the convoluted shape of the diaphragm as it travels relative to the at least one vent.
- 16. The vent valve of claim 11, further comprising:
at least one channel provided between a portion of the housing and the float providing a tortuous path through which fuel vapor must travel, the tortuous path providing surfaces to facilitate condensation of liquid carried in the fuel vapor, draining of the condensate into the fuel tank.
- 17. A vent valve for use in controlling passage of fuel vapor in a fuel tank, comprising:
a housing for attachment to a fuel tank; a wall of the housing defining a cavity; a float contained in the housing; the float being responsive to a level of liquid in the fuel tank; the housing having a passage therein communicating with an internal portion of the tank for returning fuel vapor and liquid fuel to the tank; a portion of the housing having at least one vent therein, the vent being positioned proximate to and communicating with the passage; a flexible diaphragm attached to at least the float; the diaphragm being a generally circular diaphragm, generally concentric with the passage in the housing; a generally annular outer edge of the diaphragm being attached to the float; an annular portion of the flexible diaphragm, spaced generally radially inwardly of the outer edge of the diaphragm being displaceably positioned least proximate to the passage to control the flow of vapor through the vent and through the passage; movement of the float on a rising liquid level causing a portion of the flexible diaphragm to contact a sealing surface at least proximate to the vent to prevent the flow of fuel vapor through the vent; and movement of the float on a lowering liquid level causing the flexible diaphragm to move out of contract with the surface permitting passage of fuel vapor through the vent.
- 18. The vent valve of claim 17, further comprising:
a generally tubular wall defining the passage; the at least one vent being defined in the wall providing communication between the cavity of the housing and the passage; the flexible diaphragm being positioned generally against an outside surface of the wall; and the flexible diaphragm being displaceably positioned over the vent.
- 19. A vent valve for use in controlling discharge of fuel vapor from a fuel tank, comprising:
a housing for attachment to a fuel tank; a wall of the housing defining a cavity; a float contained in the housing; the float being responsive to a level of liquid in the fuel tank; the housing having a passage therein communicating with an external portion of the tank; a vent assembly having a primary sealing structure and a secondary sealing structure; the vent assembly having at least one vent therein, the vent being positioned proximate to and communicating with the passage; the primary sealing structure providing at least partial sealing of the passage; the secondary sealing structure providing additional sealing of the passage to prevent flow of vapors therethrough; the secondary sealing structure being attached to at least the float; the secondary sealing structure being a generally circular diaphragm, generally concentric with the passage in the housing; a generally annular outer edge of the diaphragm being attached to the float; an annular portion of the flexible diaphragm, spaced generally radially inwardly of the outer edge of the diaphragm being displaceably positioned least proximate to the passage to control the flow of vapor through the vent and through the passage; movement of the float toward the passage causing a portion of the flexible diaphragm to contact a surface of the housing at least proximate to the passage and the vent to prevent the flow of fuel vapor through the passage and vent; and movement of the float away from the passage causing the flexible diaphragm to move out of contract with the surface of the housing permitting passage of fuel vapor through the vent and passage.
- 20. A method of controlling discharge of fuel vapor from a fuel tank, the method providing a housing for attachment to a fuel tank; a wall of the housing defining a cavity; a float contained in the housing; the float being responsive to a level of liquid in the fuel tank; the housing having a passage therein communicating with an external portion of the tank; at least one vent positioned proximate to and communicating with the passage; a generally circular, flexible diaphragm attached to at least the float; the diaphragm being a generally concentric with the passage in the housing; the method comprising the steps of:
moving the float upwardly in response to a rising level of liquid in the fuel tank; positioning the diaphragm to displaceably abut surface of the housing proximate to the passage for providing a seal to prevent the flow of vapor through the vent and passage; moving the float away from the passage in response to a decrease in the liquid level in the tank; peeling of the diaphragm away from engagement with the surface of the housing in response to the movement of the float away from the passage; progressively continuing to peel the diaphragm in a generally concentric inwardly extending radial direction in response to continued movement of the float away from the passage; and disengaging the diaphragm from the surface of the housing proximate to the passage to permit passage of fuel vapor through the vent and passage.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. section 119 (e) to U.S. Provisional Application No. 60/269,443, filed Feb. 16, 2001, which is expressly incorporated by reference herein.
Provisional Applications (1)
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Number |
Date |
Country |
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60269443 |
Feb 2001 |
US |