Patent ID: 6909256

Claim:
A position control device of a position control motor, comprising: a position detection portion detecting a motor rotor position of a motor for position control, such as a brushless motor or a stepping motor; first and second control portions comparing a position detection signal from the position detection portion and a command position signal, and based on that positional deviation signal, outputting a signal corresponding to a current to be supplied to a winding of the motor; first and second distribution adjusting portions distributing the signals output from the first and second control portions with a set distribution ratio or distribution rate; a signal synthesis portion for synthesizing by vector addition the vectors of the output signals distributed by the first and second distribution adjustment portions; and an amplification portion for receiving the output signal synthesized by the signal synthesis portion and outputting the current to be supplied to the motor winding; wherein the position of the motor is controlled by the command position signal; wherein when the position deviation signal is within an electrical angle of 90°, the first control portion outputs a sine wave data signal corresponding to the command position signal from a sine wave table, and when the position deviation signal exceeds an electrical angle of 90°, the first control portion outputs a sine wave data signal, from the sine wave table, that excites the motor such that the motor is at a stable excitation point at an electrical angle of 90° ahead of the rotor position; and wherein the second control portion serves as a servo control portion or a feedback control portion and outputs the output signal, and the amplification portion increases or decreases the current to be supplied to the motor winding in accordance with a load torque applied to the motor.