Fuel injector

Abstract

The invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine. A fuel supply line enters an injector housing from a high pressure fuel source which can be hydraulically connected to a pressure chamber. A 3/2 directional control valve for injecting fuel into the combustion chamber has a valve piston which can be moved axially back and forth between a rest position and an injection position. The 3/2 directional control valve, by a first end face of the valve piston, which adjoins a hydraulic coupling chamber, is hydraulically coupled to and can be activated by a piezoelectric actuator. The 3/2 directional control has a ball element which is connected to a second end face of the valve piston and, in the rest position, can be moved against a first sealing edge and, in the injection position, can be moved against a second sealing edge. The diameter of the valve piston and the diameter of the first sealing edge have a ratio which permits the ball element to be pressed in the rest position with a small contact force against the first sealing edge. A fuel injector with a 3/2 directional control valve is therefore created which has a simple design, and complex production processes are dispensed with.

Dependencies are inferred from the claim text.