Variable venturi type carburetor

Abstract

A variable venturi type carburetor including both inner and outer venturis, a main nozzle for injecting main fuel into the inner venturi and a piston valve displaceably mounted on the outer venturi to move under the influence of negative pressure transmitted from the intake passage. The carburetor further includes an auxiliary fuel nozzle for feeding auxiliary fuel to the outer venturi in response to movement of the piston valve. The auxiliary fuel nozzle is disposed on the outer venturi adjacent to the main nozzle and the center axes of both the nozzles are located on the same or substantially same plane extending in the direction of the intake passage. A bleed air valve is mounted midway of the atmospheric pressure introduction passage which is branched from the auxiliary fuel passage so as to open the passage when higher negative pressure is transmitted from manifold. Further, a vacuum switching valve is mounted midway of the atmospheric pressure introduction passage extending from the negative pressure chamber on the valve piston so as to open the passage when higher negative pressure is transmitted from manifold. One end of each of the atmospheric pressure introduction passages for both the valves is opened to the atmosphere.

Dependencies are inferred from the claim text.