MOTOR SPEED CONTROLLER

• Main Author: ISHII HIDEKAZU
• Format: Patent
• Language: English
• Published: 02.08.1988
• 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 stabilize the rotating speed of a motor with respect to the variations in a motor load, a power source voltage, an operating temperature, etc., by disconnecting a reference voltage circuit from a power source ground side. CONSTITUTION:A reference voltage circuit 8 is connected between a first terminal 1 and the non-inverting input terminal + of an error amplifier 9, and a bias current source 16 is connected between a terminal 5 connected to a power source 15 and a reference voltage circuit 8. Accordingly, a bias current is supplied from the power source 15 without a resistor 13 to flow to a transistor 6 through the reference voltage circuit 8. As a result, the counter electromotive force of a motor 10 becomes constant irrespective of the variation of a motor current to obtain a rotating speed stabilized against a load variation. Further, even if the bias current is slightly varied according to variations in the voltage of the power source 15 and an operating temperature, its slight variation is not amplified, thereby stabilizing the rotating speed against the variations in the power source voltage and the operating temperature.