Vaporizing carburetor

Claim 1

A spark ignition internal combustion engine including a vaporization carburetor system for supplying a fuel/air mixture to the intake manifold, said vaporization carburetor system comprising an intake passageway through which atmospheric air may be drawn by the intake manifold vacuum of the engine, an air bypass tube having a first end communicating with the intake passageway, an air bypass valve positioned in the bypass tube for controlling the flow of air through the bypass tube, an intake tube having one end communicating with the intake passageway, a closed evaporation chamber for containing a supply of liquid fuel through which air may be bubbled to evaporate the fuel, means for maintaining a constant level of fuel in the evaporation chamber, said intake tube extending into the evaporation chamber with a portion of the intake tube extending below the fuel level and having at least one opening below the fuel level thereby permitting air to flow through the fuel to evaporate the fuel and form a fuel/air mixture, an outlet tube havng a first end communicating with the evaporation chamber to permit removal of the fuel/air mixture from the chamber, a throttle valve positioned in the outlet tube for controlling the rate of flow of fuel/air mixture from the evaporation chamber, a manifold inlet tube having one end communicating with the intake manifold of the engine and the other end communicating with the second end of the air bypass tube and the second end of the outlet tube, means for maintaining the air bypass valve in a closed position until the throttle valve has closed to a predetermined position and for opening the air bypass valve as the throttle valve is closed past said predetermined position.