Patent ID: 7808160
Filing Date: 2010-10-05
Classification: F02M,H01L

Abstract:
1. A piezoelectric actuator for injecting fuel at a predetermined fuel pressure; comprising: a) a casing at least laterally delimiting an actuator interior space and exhibiting at least one of a temperature- and pressure-dependent first change in volume; b) a piezoelectric stack arranged in the actuator interior space and exhibiting at east one of a temperature- and pressure-dependent second change in volume; c) a transfer agent arranged between the piezoelectric stack and the casing for the purpose of transferring the fuel pressure applied externally to the casing onto the piezoelectric stack, the transfer agent having a passivating fluid which exhibits at least one of a temperature- and pressure-dependent third change in volume and a plurality of preformed bodies which exhibit at least one of a temperature- and pressure-dependent fourth change in volume, the ratio between the passivating fluid and the preformed bodies being set in such a way that the first change in volume of the casing essentially corresponds to an overall change in volume of the actuator interior space which includes at least the second, third and fourth change in volume.