Systems and methods for preventing fuel tank overfilling
First Claim
1. A method comprising:
- pressurizing a vessel external to a fuel tank that supplies fuel to a vehicle engine; and
while a fuel level in the fuel tank is increasing during a refueling event, selectively coupling the vessel to the fuel tank to pressurize the fuel tank to a predetermined pressure threshold responsive to an indication that the fuel level in the fuel tank has reached a capacity of the fuel tank, where the pressurizing the fuel tank desorbs fuel vapors stored in a fuel vapor storage canister to the fuel tank.
1 Assignment
0 Petitions
Accused Products
Abstract
Methods and systems are provided for preventing fuel tank overfilling during refueling events, wherein overfilling of the fuel tank is prevented by delivering a pressure pulse to the fuel tank responsive to a fuel fill level reaching a predetermined threshold, or responsive to an attempt to add additional fuel subsequent to the fuel fill threshold being reached. In one example, an onboard pressure vessel is actively pressurized via an onboard pump, where the pressure may be actively released and routed to the fuel tank to induce an automatic shutoff of a refueling dispenser pump under predetermined conditions. In this way, automatic shutoffs of refueling dispenser pumps may be rapidly and reliably induced, thus preventing fuel tank overfilling, prolonging the lifetime of fuel vapor storage canisters, and reducing undesired evaporative emissions.
-
Citations
18 Claims
-
1. A method comprising:
-
pressurizing a vessel external to a fuel tank that supplies fuel to a vehicle engine; and while a fuel level in the fuel tank is increasing during a refueling event, selectively coupling the vessel to the fuel tank to pressurize the fuel tank to a predetermined pressure threshold responsive to an indication that the fuel level in the fuel tank has reached a capacity of the fuel tank, where the pressurizing the fuel tank desorbs fuel vapors stored in a fuel vapor storage canister to the fuel tank. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A system for a vehicle, comprising:
-
a fuel tank in a vehicle fuel system coupled to a fuel vapor canister in a vehicle evaporative emissions control system via a vapor recovery line; a fuel tank isolation valve positioned in the vapor recovery line between the fuel tank and the fuel vapor canister; an onboard pump positioned in a vent line between the fuel vapor canister and atmosphere, the onboard pump a component of an evaporative level check monitor (ELCM) and wherein the ELCM additionally includes a changeover valve (COV) configurable in a first position and a second position; a pressure vessel coupled to the vent line via a vessel line between the onboard pump and the fuel vapor canister; a vessel valve positioned in the vessel line between the pressure vessel and the vent line; a canister purge valve positioned in a purge line between the fuel vapor canister and an intake manifold of a vehicle engine; an evaporative emissions control system pressure sensor; and a controller, storing instructions in non-transitory memory that, when executed, cause the controller to; command or maintain closed the fuel tank isolation valve and the canister purge valve; command open the vessel valve; configure the COV in the second position and activate the onboard pump to pressurize the evaporative emissions control system and the pressure vessel; command closed the vessel valve responsive to a pressure in the evaporative emissions control system reaching a predetermined pressure threshold to store the pressure; and control the vessel valve responsive to a fuel tank refueling event. - View Dependent Claims (10, 11, 12, 13, 14)
-
-
15. A method for a vehicle comprising:
-
inducing an automatic shutoff of a refueling dispenser during a refueling event where fuel is added to a fuel tank via the refueling dispenser, by directing a pressure wave from an onboard pressure vessel to the fuel tank responsive to a fuel fill level in the fuel tank reaching a predetermined fuel fill level, the onboard pressure vessel selectively coupled via a vessel valve to a vent line that couples a fuel vapor canister to an onboard pump; where the automatic shutoff is induced via pressure in the fuel tank reaching a predetermined fuel tank pressure threshold under conditions where fuel vapors stored in the fuel vapor canister are being desorbed to the fuel tank via the directing the pressure wave from the onboard pressure vessel to the fuel tank. - View Dependent Claims (16, 17, 18)
-
Specification