Actuator module for use in e.g. diesel piezoelectric injector, has elastomer layer surrounded by bellow made from material that is diffusion resistant against medium surrounding bellow such that bellow pre-stresses piezoelectric units

摘要

The module has a piezoelectric actuator (3) with piezoelectric units (6) arranged between a head part (14) and a base part (11). An elastomer layer (15) is surrounded by a shaft bellow (16) made from a metallic material e.g. steel, that is diffusion resistant against a medium surrounding the shaft bellow in such a manner that the shaft bellow pre-stresses the piezoelectric units simultaneously against the head part and/or the base part of the piezoelectric actuator. The shaft bellow is welded with the head part and/or base part.