SPEED CONTROL CIRCUIT FOR DC MOTOR

• Main Authors: NOZAKI YUTAKA, ENDO HIROBUMI, MATSUMOTO HIDETOSHI, OMORI KOJI
• Format: Patent
• Language: English
• Published: 26.07.1988
• Subjects: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS

PURPOSE:To arbitrarily and easily set a point in which a feedback effect starts operating by providing a current mirror circuit for feeding back a feedback signal to a speed setting variable resistor. CONSTITUTION:A comparator 5 switches a motor driving element Tr1 at an ON duty obtained by comparing a set voltage V1 with a voltage V2 from a triangular wave oscillator 3. Here, when the motor speed N is decelerated so that the collector voltage of the element Tr1 exceeds the breakdown voltage of a constant-voltage diode ZD1, a current mirror circuit 9 is turned ON. Accordingly, the potential of the connecting point (b) of the variable resistor VR1 of a motor speed setter 4 to a resistor R1 is reduced, the ON time of the element Tr1 is increased, and the rotating speed of the motor M is accelerated.