DRIVING METHOD OF DC MOTOR

摘要

PURPOSE:To improve the starting and stopping characteristics of the Dc motor and to reduce the heat of the transistor by conducting the power transistor when the rotary position feedback pulse is delayed from the reference input pulse and conducting the brake transistor when it is advanced. CONSTITUTION:The output of a rotary angle detector 5 connected directly to the motor 4 is shaped by a waveform shaper 6 to obtain a feedback pulse fFB, which is compared in phase with a reference input pulse fIN by a tertiary phase comparator 7. The comparator 7 produces a positive output when the phase of the feedback pulse fFB is lag from the input pulse fIN and a negative output when it is lead therefrom. A power transistor 10 is connected through the first level discriminator 8 conducted when the output is positive to the output side of the comparator 7, and a brake transistor 11 is connected through the second level discriminator 9 conducted when the output is negative thereto.