Fuel system and method for managing fuel vapor pressure with a flow-through diaphragm
First Claim
1. A fuel system for supplying fuel to an internal combustion engine, the fuel system comprising:
- a fuel tank having a headspace;
an intake manifold of the internal combustion engine in fluid communication with the headspace;
a fuel vapor collection canister in fluid communication with the headspace;
a purge valve having a first side in fluid communication with the intake manifold and having a second side in fluid communication with fuel vapor collection canister and with the headspace; and
a fuel vapor pressure management apparatus including;
a housing coupled to the fuel vapor collection canister and defining an interior chamber;
a pressure operable device including a diaphragm separating the interior chamber into a first portion in fluid communication with the fuel vapor collection canister and a second portion in fluid communication with a vent port, the diaphragm including a central portion movable along an axis, a peripheral portion fixed with respect to the housing, and an intermediate portion coupling the central and peripheral portions, a first arrangement of the pressure operable device occurs when there is a first negative pressure level in the fuel vapor collection canister relative to the vent port and the diaphragm is in a nearly undeformed configuration, a second arrangement of the pressure operable device permits a first fluid flow from the vent port to the fuel vapor collection canister when the diaphragm is in a first deformed configuration, and a third arrangement of the pressure operable device permits a second fluid flow from the fuel vapor collection canister to the vent port when the diaphragm is in a second deformed configuration; and
a switch signaling the first arrangement of the pressure operable device.
2 Assignments
0 Petitions
Accused Products
Abstract
A fuel system and a method of method of managing fuel vapor pressure in the fuel system. The fuel system a fuel tank having a headspace, a fuel vapor collection canister in fluid communication with the headspace, a purge valve, and a fuel vapor pressure management apparatus. The method includes performing leak detection on the headspace, and preventing a flow of fluid through an elastic diaphragm during leak detection. The elastic diaphragm includes at least one opening through which passes the flow of fluid. And the preventing the flow of fluid includes a first portion of the elastic diaphragm sealingly engaging a second portion of the elastic diaphragm. The method further includes relieving excess negative pressure in the headspace and relieving excess positive pressure in the headspace by fluid flow in different directions along the same flow path that includes the opening in the diaphragm.
57 Citations
19 Claims
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1. A fuel system for supplying fuel to an internal combustion engine, the fuel system comprising:
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a fuel tank having a headspace;
an intake manifold of the internal combustion engine in fluid communication with the headspace;
a fuel vapor collection canister in fluid communication with the headspace;
a purge valve having a first side in fluid communication with the intake manifold and having a second side in fluid communication with fuel vapor collection canister and with the headspace; and
a fuel vapor pressure management apparatus including;
a housing coupled to the fuel vapor collection canister and defining an interior chamber;
a pressure operable device including a diaphragm separating the interior chamber into a first portion in fluid communication with the fuel vapor collection canister and a second portion in fluid communication with a vent port, the diaphragm including a central portion movable along an axis, a peripheral portion fixed with respect to the housing, and an intermediate portion coupling the central and peripheral portions, a first arrangement of the pressure operable device occurs when there is a first negative pressure level in the fuel vapor collection canister relative to the vent port and the diaphragm is in a nearly undeformed configuration, a second arrangement of the pressure operable device permits a first fluid flow from the vent port to the fuel vapor collection canister when the diaphragm is in a first deformed configuration, and a third arrangement of the pressure operable device permits a second fluid flow from the fuel vapor collection canister to the vent port when the diaphragm is in a second deformed configuration; and
a switch signaling the first arrangement of the pressure operable device. - View Dependent Claims (2, 4, 5, 6, 7, 8, 9)
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10. A method of managing pressure in a fuel system supplying fuel to an internal combustion engine, the fuel system including a fuel tank partially defining a headspace, the method comprising:
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connecting in fluid communication a fuel vapor collection canister to the headspace;
connecting in fluid communication a fuel vapor pressure management apparatus to the fuel vapor collection canister, the fuel vapor pressure management apparatus performing leak detection on the headspace, the fuel vapor management apparatus including;
a housing coupled to the fuel vapor collection canister and defining an interior chamber;
a diaphragm dividing the interior chamber into a first portion in fluid communication with the fuel vapor collection canister and a second portion in fluid communication with a vent port; and
establishing a fluid flow path extending between the fuel vapor collection canister and the vent port, the establishing including passing through the first portion of the interior chamber, passing through a plurality of apertures penetrating the diaphragm, and passing through the second portion of the interior chamber;
relieving with the fuel vapor pressure management apparatus excess negative pressure in the fuel vapor collection canister via fluid flow in a first direction along the fluid flow path; and
relieving with the fuel vapor pressure management apparatus excess positive pressure in the fuel vapor collection canister via fluid flow in a second direction along the fluid flow path, the second direction being opposite to the first direction. - View Dependent Claims (11, 12, 13)
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14. A method of managing fuel vapor pressure in a fuel system supplying fuel to an internal combustion engine, the fuel system including a headspace, the method comprising:
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performing leak detection on the headspace of the fuel system; and
preventing a flow of fluid through an elastic diaphragm during the performing leak detection, the elastic diaphragm including at least one opening through which passes the flow of fluid, and the preventing the flow of fluid including a first portion of the elastic diaphragm sealingly engaging a second portion of the elastic diaphragm. - View Dependent Claims (15, 16, 17, 18, 19)
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Specification