Fuel injection apparatus having at least one fuel injection valve for high-powered engines

A fuel injection apparatus for high-powered engines or the like and including at least one fuel injection valve having a housing with a valve body axially displaceable within the housing, a pressure chamber connected via a connecting line with a fuel delivery line, the valve body having a first face projecting into said pressure chamber and provided with a needle valve cooperating with a valve seat and a second face which is subjected to fuel pressure at the direction of a control means so that the valve seat is sealed by means of the needle valve and is pressure relieved at said second face to effect injection, whereby the valve body with its needle valve is lifted from the valve seat via said first face oriented toward the needle valve which is subjected to the injection pressure, the improvement which comprises:

• an obturation mechanism provided in said fuel delivery line leading to said pressure chamber, a return line connected with said obturation mechanism, said obturation mechanism arranged to permit said connecting line leading to said pressure chamber to be selectively connected first with the fuel delivery line and then with said return line, and means for controlling said obturation mechanism in synchronism with the injection so that the connecting line between the pressure chamber and the fuel delivery line is interrupted at least during a large portion of the pause between injections and is opened for a period which is somewhat longer than the duration of injection.