Patent ID: 7121476
Filing Date: 2006-10-17
Classification: F02M

Abstract:
1. In a fuel injection device, which has: a nozzle needle, guided displaceably in a nozzle body, which as a function of its position opens or closes at least one injection opening, in which a control chamber, to which fuel can be delivered under pressure via an inlet throttle and from which fuel can be diverted, controlled by a control valve, via an outlet throttle, is provided at a piston face of the nozzle needle facing away from the injection opening, and in which in operation, the position of the nozzle needle is controlled by a pressure difference between the pressure in the control chamber and the pressure of the fuel at the end, toward the injection opening, of the nozzle needle, the improvement wherein, during operation, the nozzle needle is surrounded by fuel at high pressure along its entire length, except for the end of the nozzle needle at the at least one injection opening and the piston face of the nozzle needle, such that only in the regions of the nozzle needle near the injection opening and at the piston face which is within the control chamber can a lower pressure, differing from the high fuel pressure, occur.