Fuel injector with a directly controlled valve needle

摘要

The injector has a piezo-actuator (13) comprising an actuator base (14). A piezo-electric element (16) is surrounded by a casing (20) that is connected with the actuator base and an actuator head (15) in a high pressure-sealed manner. An annular space is provided between the casing and the piezo-electric element, and is filled with an elastomer (24). The actuator head comprises an axially shiftable guided compensating element that has two front sides (25a, 25b), where the front side (25a) is subjected with elastomer and the front side (25b) is subjected with high pressure of a fuel.