Low silhouette dual flow stage carburetor

Claim 1

A low silhouette dual flow stage carburetor having an air/fuel induction passage with an essentially constant area at one end, and adapted to be connected to an engine intake manifold at its other end, said inlet having a rounded inlet edge, a throttle valve rotatably mounted in said passage for movement between closed and wide open positions to control flow through said passage, a fuel and air flow control member rotatably mounted anterior of said valve and spaced from the walls of said passage, said member having an arcuate contour so as together with said air inlet rounded edge define a variable area venturi varying in area as a function of the rotative movement of said control member, and a fuel nozzle opening into said passage at a point adjacent said venturi so as to be subject to the varying pressure signal therein for the flow of fuel at times therefrom into said passage, said member being variably movable from an initial stage minimum venturi area position at low throttle valve angle positions and low air flows providing a high venturi fuel metering signal, to a second stage maximum venturi area position at wide open throttle valve position providing high air flow through said passage.