Abstract: Disclosed are a method for operating a piezoelectric drive system (10) used for adjusting movable parts (12, 14), especially in a motor vehicle (13), as well as a piezoelectric drive unit (10) comprising at least one piezo motor (12) that is fitted with at least one piezo actuator (18). At least one frictional element (30) of the piezo motor (12) makes it possible to generate a relative movement in relation to a frictional surface (14) located across from the frictional element (30). The at least one piezo actuator (18) is triggered with an excitation signal (93) by means of an electronic unit (42). A response signal (130) of the drive system (10) is detected using the at least one piezo actuator (18), a change in the load of the drive system (10) being recognized as a result of a change in the response signal (130).

Abstract: Disclosed are a piezoelectric drive unit (10) and a method for operating such a drive unit in order to adjust movable parts (11), especially in a motor vehicle. Said piezoelectric drive unit (10) comprises at least one piezo motor (12) that is fitted with at least one piezo actuator (18). At least one frictional element (30) of the piezo motor (12) makes it possible to generate a relative movement in relation to a frictional surface (14) located across from the frictional element (30). Said at least one frictional element (30) is disposed on a bridging web (28) of the motor (12). The bridging web (28) places the frictional element (30) at a distance (2) from the central axis (89) of the at least one piezo actuator (18), said central axis (89) extending in a longitudinal direction (19).

Abstract: The invention relates to a piezoelectric drive device for adjusting movable parts (11), particularly in a motor vehicle, having a piezo motor (12) having at least one piezo actuator comprising an electric piezo element, wherein at least one friction element (30) is disposed on the piezo motor (12), said element interacting with a friction surface (14) of at least one guide rail (16) opposite said friction element (30) for creating a relative movement, wherein the friction surface is positioned opposite of the friction element (30), wherein the at least one piezo motor (12) is supported on a first side (94) of a bearing bracket (8) and a counter element (98) is disposed on a second opposite side (95) of the bearing bracket (8), which exerts a counter force (97) to the friction element (30) onto the at least one guide rail (16).