US 2009/0288645 A1 · Evaporative Emission Management For Vehicles

Abstract

Evaporative emissions management for a vehicle having a fuel tank and a low-vacuum internal combustion engine, including hybrid electric vehicles, include first and second canisters with the second canister disposed between the first canister and atmosphere. A refueling valve routes fuel vapors from the fuel storage tank through the first canister, and to the second canister when the first canister becomes saturated, during refueling. Other than during refueling, the refueling valve is closed to route fuel vapors around the first canister and directly into the second canister. First and second purge valves are controlled during canister regeneration or purging so air from atmosphere is routed primarily through the second canister to the engine to purge the second canister before the purge valves are operated to route air from atmosphere through both the second and first canisters to purge the first canister.

Claims20

Dependent claims

An evaporative emissions management system for a vehicle having a fuel storage tank and an internal combustion engine, the system comprising:

a first canister having a first vapor storage capacity selectively fluidly coupled to the fuel storage tank;
a second canister having a second vapor storage capacity greater than the first vapor storage capacity fluidly coupled to the first canister and selectively fluidly coupled to atmosphere;
and
a refueling valve selectively operable by fuel cap removal to route fuel vapors from the fuel storage tank through the first canister and to the second canister when the first canister becomes saturated during refueling of the fuel storage tank, the refueling valve causing fuel vapors from the fuel storage tank to travel around the first canister and directly into the second canister when the fuel cap is secured.

1 more element

An evaporative emissions management system for a vehicle having a fuel storage tank and an internal combustion engine, the system comprising:

a first vapor storage canister having a first vapor storage capacity fluidly coupled to the fuel storage tank;
a second vapor storage canister having a second vapor storage capacity fluidly coupled to the first canister, the fuel storage tank, and atmosphere;
a refueling valve disposed between the fuel storage tank and the first canister selectively operable to allow fuel vapors to flow from the fuel storage tank through the first canister;
a first purge valve disposed between the first vapor storage canister and the internal combustion engine;
a second purge valve disposed between the second vapor storage canister and the internal combustion engine;
a vent valve disposed between the second vapor storage canister and atmosphere;
and
a controller in communication with at least the first and second purge valves and the vent valve, the controller selectively operating the first and second purge valves and the vent valve to purge the second vapor storage canister prior to operating the first and second purge valves and the vent valve to purge the first vapor storage canister.

5 more elements

Dependencies are inferred from the claim text.

Evaporative Emission Management For Vehicles

Life of this patent

Evaporative Emission Management For Vehicles

Life of this patent

Abstract

Claims20