Patent ID: 8072168

Claim:
A reference position detecting apparatus comprising: an electric motor that includes a first coil group having a plurality of first coils and a second coil group having a plurality of second coils, the first coil group being electrically separated from the second coil group, the electric motor further including a rotor that rotates when at least one of the first coil group and the second coil group is supplied with electricity; a tapping control unit that performs tapping control in which the rotor is rotated to a limit position on one side in a predetermined range by electricity supplied to one of the first coil group and the second coil group; a reference position recognizing unit that defines a point at which rotation of the rotor stops during tapping control, as a reference position, and that stores the reference position; and a normal control unit that performs, after the reference position is stored by the reference position recognizing unit, a normal control in which electricity is supplied to both the first coil group and the second coil group.