CIRCUIT FOR REVERSING THE ROTATION SENSE OF A D.C. MOTOR

摘要

1. A circuit arrangement for reversing the direction of rotation of a d.c. motor, in particular a d.c. miniature motor for operating dentistry tools, characterized in that a high frequency alternating voltage (UG ) is superimposed onto the motor voltage from a pulse generator (7), a blocking element (choke 13) isolates the superimposed voltage from the motor supply (voltage source 2) and a switching element (switch 10) connects a capacitor (9) in parallel with the d.c. motor (1) when it is operated, whereby a voltage jump (Figure 2b) is produced in the control line of the pulse generator (7), and a switching stage (5) is provided which converts the voltage jump into a switching pulse to reverse the polarity of the motor terminals via a relay (4).