PURPOSE: To provide a brushless motor which has an excellent speed controlling function and reduces the space and cost of a system.
CONSTITUTION: A brushless motor comprises the stator, wherein a stator winding 2, a rotor positional sensor 4, and a print-circuit board mounting a driving circuit 5 on it are molded and are solidified in a body, and a permanent magnet rotor 3. Also, the driving circuit 5 is an one-chip integrated circuit providing with a switching power element part 6, a means 9 for generating a speed error signal by comparing the rotational speed signal obtained from the rotation of the motor with a speed command signal inputted from the outside, a PWM (pulse width modulation) controlling means 10, and a means 7 for generating driving signals, wherein based on the output of the rotor positional sensor 4 and the output of the PWM controlling means 10, generated are the signals which so switch on or off the switching power elements as to reduce the speed error signal.
DOI YUJI
NAKANO HIROMITSU
YASOHARA MASAHIRO
OKU HIROYUKI
