BRUSHLESS MOTOR

摘要

PURPOSE:To give a stepping function and a positioning function by selectively phase-advancing a positional signal obtained from a noncontacting sensor incorporated into a motor and energizing a coil by the phase-advanced positional signal. CONSTITUTION:A noncontacting sensor 26 is incorporated nito a motor 20 with a rotor 21 and three-phase coils 25a-25c. An output from the noncontacting sensor 26 is inputted to a phase advancing circuit 31 and an F/V converting circuit 36 through amplifiers 30a-30c. An electronic switch circuit 33 receives stepping command signals from the outside, and selects one signal from six signals in total of positional signals and inverted positional signals and outputs it. An output from the electronic switch circuit 33 is transmitted over an adder 37, and added to an output from the F/V converting circuit 36 and phase-advacing bias voltage 39. An output from the adder 37 is transmitted over the phase advancing circuit 31. A three-phase full wave type rectangular wave drive circuit 32 flows currents through the coils 52a-25c for the three-phase motor 2 in response to the change of the polarity of phase-advanced positional signals.