Fuel injection system for externally ignited internal combustion engines

Claim 1

In a fuel injection system associated with an externally ignited internal combustion engine, said system being of the type that includes (A) a suction tube through which air is drawn to said engine, (B) an arbitrarily operable butterfly valve disposed in said suction tube, (C) a throttle member disposed in said suction tube in series with said butterfly valVe and displaceable as a function of the upstream and downstream air pressure (D) fuel injection means to introduce fuel into the stream of intake air for obtaining a fuel-air mixture, (E) fuel conduit means to deliver fuel to said fuel injection means and (F) a fuel metering valve operating with a constant pressure drop in said fuel conduit means and actuated by said throttle member for controlling the flow of fuel to said fuel injection means, the improvement comprising, (A) a control plunger forming part of said fuel metering valve, said plunger including an oblique control edge determining a flow passage section for said fuel in said fuel conduit means, said control plunger being axially displaceable for entirely closing said flow passage section to cut off fuel supply to said fuel injection means and (B) means connecting said throttle member with said control plunger for turning the latter in response to the displacement of said throttle member to vary said flow passage section.