Patent ID: 7638929

Claim:
A piezo electric motor for generating a relative movement between a reference part ( 2 ) and a drive part ( 1 ), comprising: a plurality of clamping piezo packs ( 8 ) arranged between the reference part ( 2 ) and the drive part ( 1 ), said clamping piezo packs ( 8 ) being oriented so as to extend about normal to the direction of a relative movement between the drive part ( 1 ) and the reference part ( 2 ) and supported each with one end to the reference part ( 2 ) and at the opposite end being disposed with a foot ( 11 ) in frictional engagement with the drive part ( 1 ), the clamping piezo packs ( 8 ) comprising at least two groups which are alternately electrically energized, a bridge member which is supported under pretension on the reference part ( 2 ) and which is semi-rigid such that, in a static state, it is sufficiently flexible for accommodating length tolerances of the clamping piezo pack, but acts rigidly when dynamically loaded by the piezo forces at the piezo operating frequency, a plurality of stepping piezo packs ( 9 , 10 ) of which each is assigned to a clamping piezo pack ( 8 ) and arranged about parallel to the direction of the relative movement between the drive part ( 1 ) and the reference part ( 2 ) and are fixed each with one end at the reference part and having an opposite end which is connected to the foot ( 11 ) of the associated clamping piezo pack ( 8 ), said clamping piezo pack ( 8 ) being connected each with the respective foot ( 11 ) via a quasi-joint, and the foot ( 11 ) being further connected via another quasi-joint to a counter support structure ( 16 ) at a location, which is spaced from the connecting point to the respective clamping pack ( 8 ), the respective assigned stepping piezo pack ( 9 ) being connected to the foot ( 11 ) at a location disposed between the connecting point to the support ( 16 ) and the drive side end of the foot ( 11 ) or the connecting point with the clamping piezo pack.