초록

Vehicle tank pressure is controlled by adsorbing air from the tank in a zeolite bed, and passing fuel vapor back to the tank. The zeolite is later regenerated by application of heat and vacuum.

대표청구항 ▼

In a vehicle having a fuel storage tank that produces a mixture of air and hydrocarbon vapor that pressurizes said tank, and which requires pressure relief above a predetermined threshold, a method for controlling said tank pressure, comprising the steps of, providing a source of selectively applica

In a vehicle having a fuel storage tank that produces a mixture of air and hydrocarbon vapor that pressurizes said tank, and which requires pressure relief above a predetermined threshold, a method for controlling said tank pressure, comprising the steps of, providing a source of selectively applicable vacuum, providing a source of selectively applicable heat, providing said fuel tank with a pressure control port that opens in response to an increase in tank pressure above said predetermined threshold, providing a closed container filled with zeolite of the type that adsorbs air, but passes hydrocarbon vapor, and from which air may be desorbed by applying heat and vacuum, providing a selectively openable and closable inlet line between said tank control port and said container, providing a selectively openable and closable outlet line between said container and said fuel tank, opening said inlet line and said outlet line, when said tank pressure threshold has been exceeded, thereby admitting air and hydrocarbon to said container, with said air being adsorbed in said zeolite and said hydrocarbon passing back to said fuel tank through said first outlet line, and, closing said inlet line and said first outlet line, and simultaneously applying said heat and vacuum source to said canister, when said zeolite has adsorbed its capacity of air, thereby allowing air to be desorbed from said zeolite.