distances relative to the support point of the levers on the washer the respective point of action of the two levers is in a notch on the nozzle needle 8 the axial pressing force of the piezo actuator 1 is transmitted to the nozzle needle 8 by the mechanism described above the nozzle needle is lifted out of its seat as soon as the lever force is larger than the sum of the spring force and the hydraulic force and the elasticity of the nozzle body 9 no longer ensures that the needle seat follows on with the nozzle needle after a defined travel of for example 100 u03bcm which is executed at a pressure of 200 mpa the needle stop impacts against the washer a contact force builds up which has a reaction on the piezo actuator 1 with such piezo actuators 1 it is possible to lift the nozzle needle 8 only partially out of its seat and hold it in what is referred to as the partial stroke the cleared flow cross section between the nozzle needle and the nozzle body is smaller here than the sum of the cross sections of all the nozzle holes the piezo actuator 1 is discharged at a subsequent.