AC power source direct-coupled brushless DC motor and electrical equipment equipped with the same

摘要

PPROBLEM TO BE SOLVED: To provide a brushless DC motor, directly connectable to an AC power supply that is compatible with 2 or more stages of speed control and 2 or more models. PSOLUTION: The voltage value to be generated by a low-voltage DC voltage conversion means 8 is changed by a low-voltage DC voltage conversion means 14, by switching a switch 22 arranged outside a brushless DC motor that is directly connectable to an AC power supply 1, to change voltage values, corresponding to the number of AC power supply connection means 15, to be applied to an inverter circuit 6. The voltage generated by a reference voltage generating means 24 is extracted outside via a low-voltage DC voltage extraction terminal 25, and after the voltage is reduced, the voltage is introduced inside through a duty ratio set value input means 26 as a duty-ratio specification voltage for specifying the ON/OFF duty ratio for a PWM control means 23, and the voltage can change the ON/OFF-duty ratio, when PWM-controlling lower side switching elements Q2, Q4, Q6. The brushless DC motor, directly connectable to the AC power supply 1, can be compatible with multi-stage speed control and a plurality of models, by combination. PCOPYRIGHT: (C)2008,JPO&INPIT