KOBLING TIL STYRING AF DRIFTEN AF TANDLAEGERS BEHANDLINGSINSTRUMENTER

摘要

A circuit arrangement is provided for controlling the drive of dental treatment instruments by means of driving devices associated therewith and the operating data of which are adapted to be fed to a separate forward/backward counter when the particular treatment instrument is selected for use. A starter switch is connected to the forward/backward counter and is operable, when actuated, to vary the particular stored count of the counter step-wise for the purpose of varying the operating data and for transmission to a control element, for the control thereof, which is associated with the particular treatment instrument. Upon actuation of the starter switch in order to vary the stored count of the forward/backward counter, the counting speed of the counter is increased with increasing actuation time of the starter switch by reason of the fact that the counter receives a number of counter pulses which increase per unit time.