Patent ID: 7635961

Claim:
A reference position detecting apparatus comprising: an electric motor that includes a coil device and a rotor, the rotor rotating when the coil device is supplied with electricity; a driven object that is driven by the rotating rotor; a tapping control unit that performs a tapping control, in which the rotor rotates to a limit position on one side in a movable range of the driven object; and a reference position recognizing unit that defines a point, at which rotation of the rotor stops, as a reference position of one of the rotor and the driven object during the tapping control, wherein the coil device has a first coil group and a second coil group, the first coil group includes a plurality of first coils, which electrically connect with each other, the second coil group includes a plurality of second coils, which electrically connect with each other, the first coil group including the plurality of first coils is electrically separated from the second coil group including the plurality of second coils, and the tapping control unit controls electricity supplied to either one of the first coil group and the second coil group to rotate the rotor during the tapping control.