CARBURETOR FOR INTERNAL COMBUSTION ENGINE Russian patent published in 2001 - IPC

FIELD: mechanical engineering; carburized engines. SUBSTANCE: carburetor has a body, fuel-air duct with larger Venturi and smaller Venturi (atomizer), throttle valve with drive and system to deliver fuel to atomizer. Atomizer fuel feed system is coupled with additional self-contained idling system through idling system containing fuel and air jets and outlet channel. Additional self-contained idling system has a channel bypassing carburetor throttle valve with local narrowing (diffuser), control elements and shutoff valve to cut off mixture delivery at limit speed only. Passage part of smaller Venturi (atomizer) is made in the form of series-connected nozzle, cylinder and cone, ratio of nozzle and cylinder diameters is 0.75-0.85. Channel to deliver fuel-air mixture into cylindrical part of atomizer is connected also by vertical hole with carburetor inlet neck. Ratio of diameters o said hole and channel is 0.2-0.25. Idling system has an additional air jet and tube with fuel and air jets, mixture forming space and fuel-air mixture outlet holes is arranged between fuel and air jets. Bypass channel of self-contained system is coupled with idling system by two channels one of which is located before control element. Said channel opens into local narrowing (diffuser) of bypass channel and is provided with constant-section jet (calibrated hole). Another channel located after control element is provided with a device to adjust size of flow section. EFFECT: improved accuracy of fuel metering and conditions of fuel-air mixture preparation, improved operating characteristics of engine and automobile as to fuel consumption and toxicity of exhaust gases. 4 cl, 4 dwg