Patent ID: 7872398

Claim:
A piezoelectric actuator module, comprising a piezoelectric actuator having a multilayer construction of piezoelectric elements, inner electrodes disposed between piezoelectric layers of the piezoelectric elements, the inner electrodes subjected in alternation to a different polarity of an electrical voltage in a direction of layer construction of the piezoelectric actuator, an actuator foot and an actuator head both made of steel, and an elastic insulation medium embodied as a flexible hose surrounding at least the piezoelectric elements within predetermined limits, at least one annular groove or recess disposed on the actuator foot and/or on the actuator head, and a material filling the groove or recess, the material being connectable or cross-linkable with the insulation medium, wherein at least above the at least one groove or recess having the material, the flexible hose is disposed and is connected to or cross-linked with the material in the groove or recess.