Patent ID: 8692492

Claim:
A method for setting a lead-angle value of a motor drive control circuit that drives a winding, with an energizing timing obtained based on a stored lead-angle value set in advance, of a brushless motor comprising a stator wound with the winding, and a rotor disposed rotatably and confronting the stator, the method comprising steps of: rotating the rotor at a predetermined rpm; energizing and driving the winding while switching the lead-angle value during the rotation at the rpm; calculating an average value of current amount that energizes the winding with a correlation established to each of lead-angle values being switched; calculating a total value of the average value corresponding to one of the lead-angle values and other average values before and after the average value, the total value being calculated for each of the lead-angle values; finding a smallest total amount among the total values; and setting a lead-angle value corresponding to the smallest total value as the stored lead-angle value applied to the rpm.