Method For Determining The Force Conditions At The Nozzle Needle Of A Directly Driven Piezo Injector

摘要

A method is disclosed for determining the force acting on the nozzle needle of a directly driven piezo injector, in which an electrical voltage is built on the piezo actuator which drives the nozzle needle by means of a charging process. After the charging process has ended, the voltage at the piezo actuator is measured again. A voltage gradient is determined from consecutive voltage values. Conclusions of the force acting on the nozzle needle are drawn from the voltage gradients.