FIELD: engine engineering. SUBSTANCE: plunger of a high- pressure pump supplies a controllable portion of fuel to a pump-nozzle with a step piston. The pressure of the fuel is increased simultaneously in space 42 in front of the stop surface of the great diameter piston step and in space 44 under small diameter piston step 10 before the step piston begins to move by increasing the pressure of the beginning of motion up to a pressure that characterizes one-phase fuel condition. The high pressure moves the step piston. The pressure in space 44 under small diameter piston step 10 is secondary increased in consistent with the ratio of the area of the cross-section of great diameter piston step 9 to the area of small diameter piston step 10 in response to the pressure rise above great diameter piston step 9. The fuel is injected into the engine cylinder through the nozzle sprayer. Great diameter piston step 9 is differential surface 16, the are of which is greater than the cross-section of small diameter piston step 10 , and stop surface 17, the bearing diameter of the stop surface of which is greater than the small diameter piston step. EFFECT: enhanced efficiency. 6 cl, 1 dwg
