The invention provides a motor unit having: a motor; a control unit that outputs a pulse signal that controls a rotational speed of the motor; and a drive unit that supplies the pulse according to thepulse signal. The motor provides a drive current; and an observation unit that observes the actual rotational speed of the motor. The control unit includes: a plurality of calculation units that calculate a control value of the rotational speed of the motor; and a pulse generation unit that has a plurality of control phases during a period from the start of the motor to the final target rotational speed, the pulse generation The unit selects one of the control values calculated by the plurality of calculation units in each control stage, and generates the pulse signal based on the selected one of the control values. The plurality of calculation units include a first calculation unit that calculates a control value that causes the rotation speed to rise in a constant pattern, the control value that causes the motor to have a first target rotation speed that is smaller than the final target rotation speed The control value of the rotation is an upper limit, and the pulse generation unitselects the control value calculated by the first calculation unit in the first stage after the motor is started.