Patent ID: 6647969
Filing Date: 2003-11-18
Classification: B25C,F02M,Y02T

Abstract:
An evaporation chamber system for use with an engine for a gas-powered tool to convert liquefied petroleum gas fuel (LPG) to its vaporous state for delivery to the engine, the system having an evaporation chamber with a pressure-biasing valve at an inlet end to communicate with a source of LPG and a regulator valve situated at a location remote from the pressure-biasing valve through which fuel from the evaporation chamber is passed towards a combustion chamber of the engine, the pressure-biasing valve being arranged to deliver a charge of LPG to the evaporation chamber for evaporation into a gaseous state at a lower pressure than that existing at the source of LPG, and the regulator valve being arranged to deliver at least a portion of the charge in gaseous form towards the combustion chamber at a lower pressure than that existing in the evaporation chamber, wherein the pressure-biasing valve at the inlet end of the evaporation chamber is biased toward a closed position for restricting passage of LPG into the evaporation chamber and is responsive to differential pressure between the source of LPG and the evaporation chamber so that at a predetermined lower pressure in the evaporation chamber than that existing at the source of LPG, the pressure-biasing valve is opened to admit LPG into the evaporation chamber.