DRIVING CIRCUIT OF POLAR ELECTROMAGNETIC SOLENOID FOR DIRECT CURRENT

PURPOSE:To provide a driving circuit of a polar electromagnetic solenoid for direct current which supplies optimum magnetomotive force stably and easily to an exciting coil at the time returning operation and stabilizes the operation of a driving body. CONSTITUTION:Two exciting coils 2a, 2b are connected in series and their common contact point is connected to one pole of a direct current electric power source E through a parallel circuit of a capacitor C and a resistor R. Immediately after a changing switch SWa for operation is turned on to a first contact point (a) side, charging current flows into the capacitor C since the capacitor C is not charged. As the charging of the capacitor proceeds, the current flowing in the exciting coil 2b increases and when the capacitor is completely charged, the same current flowing into the resistor R flows into the exciting coil 2b. The rise of the current flowing into the exciting coil 2b becomes steady and the time to pass the optimum exciting current range for returning becomes longer than the time needed for returning.