A motor control device for a flow control device includes an opening part through
which an upstream side of a fluid flow passage is in communication with a downstream
side of the fluid flow passage, a valve element that controls a flow of a fluid
which passes through the opening part, a motor which includes a rotor and a stator
that relatively moves the valve element with respect to the opening part and a
drive control section by which the motor is rotationally driven and controlled.
Drive pulses are outputted from the drive control section for rotationally driving
the rotor of the motor and a stop pulse is outputted from the drive control section
and set to be a period width longer than that of the drive pulse for stopping the
rotor of the motor at a prescribed position. The stop pulse is applied to the motor
and the rotor stops at the prescribed position by a magnetic detent torque between
the rotor and the stator.