摘要:
A device for moving a cleansing nozzle connected to a water supply system includes an elongated nozzle, a cylinder in which the nozzle is axially slidable, a motor having an output shaft, a drum body mounted on the output shaft, the drum body having a cylindrical rim surface and a sectoral recess extending from the surface, a sectoral insert disposed in the recess and having a partial cylindrical surface conforming to and forming a continuation of the cylindrical rim surface, and a leaf spring having one end connected to the nozzle and the other end held between the drum body and the sectoral insert such that rotation of the drum body extends and withdraws the nozzle longitudinally as the leaf spring unwraps and wraps around the drum body. The method includes counting the number of cycles of the frequency of the electric power supplied to the motor, determining the actual position of the nozzle on the basis of the counted pulses, establishing a predetermined position of the nozzle, comparing the actual position with the predetermined position, and transmitting the results of the comparison to a power circuit for the motor to turn the motor on and off so that the motor thereby positions the slidable nozzle at the predetermined position.