US Patent 11183954 Motor driving device and control method thereof

A motor driving device includes an OPEN driving mode in which a driving waveform is generated without using detection information of a rotational position of a rotor and the rotor is rotated, and a CLOSE driving mode in which a phase of a rotational position and a phase of a driving waveform are synchronized using the detection information of the rotational position of the rotor, a desired phase difference is set between the rotational position and the driving waveform, and the rotor is rotated. The CPU controls rotation of the rotor using the OPEN driving mode, instructs a driving waveform generating circuit to set a phase difference for generating a torque in a reversing direction when rotation of the rotor is reversed, switches to the CLOSE driving mode, and then switches to the OPEN driving mode again when reversing has been completed.