Air-fuel ratio control apparatus for a fuel supply system of an internal combustion engine

Abstract From the Canadian patent

An air-fuel control apparatus for an injection type internal combustion engine has an air valve of butterfly type disposed in an engine intake passage upstream of a throttle valve to define therewith an air pressure chamber and automatically operated to maintain the air pressure in the air pressure chamber substantially constant. A fuel supply circuit includes an injector at the downstream end thereof and a fuel-metering orifice between the injector and a fuel source. The fuel-metering orifice is defined by an opening in a peripheral wall of a cylinder and a fuel-metering rod slidably received in the cylinder to vary the fuel-flowing sectional area of the orifice. The air valve is …