The device (1B) has a driving tip (17) connected with component outputs. A gear unit (8) connects an electromotor (9) and a spindle-like driving bar (5) of a driving piston (11). The gear unit comprises a spiral-geared, un-selflocking end section in a back part of a longitudinal extension related to an operation position and a spindle engaging element e.g. multi-edge element, for engaging into the driving piston at a front end. The gear unit comprises an output wheel with an inner spiral bevel gear, which is adapted to a spiral bevel gear of the end section.
