Air-air/fuel control device

Claim 1

An air-air/fuel control device for a motor vehicle type internal combustion engine comprising a throttle body having an air/air-fuel induction passage open at one end to ambient air and connected at its opposite end to the engine intake manifold to be subject to the changing vacuum therein, axially spaced upstream and downstream throttle valves rotatably mounted in the passage for separate movements in a scheduled manner between open and closed positions for controlling flow through the passage, and means directly and indirectly connecting, respectively, the upstream and downstream throttle valves to the vehicle accelerator pedal for movement of each of the valves in response to movement of the pedal to assure positive movement of the upstream throttle valve in response to a movement of the pedal to a closed position regardless of the movement or non-movement of the downstream throttle valve, the diameter of the upstream valve being larger than that of the downstream valve and operating in a cross-sectional area surrounding the upstream valve larger than that surrounding the downstream valve permitting movement of the downstream valve to provide control of airflow through the passage during normal operating conditions.