A pressure adjusting valve and an electromagnetic pump are combined by using a common solenoid so as to constitute an electromagnetic valve. When the electromagnetic valve functions as the pressure adjusting valve, an instruction voltage Vc* is set and a drive circuit (90) controlled is by feedback control so that the current Ic from a current sensor which detects the current flowing in the solenoid coincides with a current instruction Ic* (S120 to S160). When the electromagnetic valve functions as the electromagnetic pump, a square wave instruction voltage Vc* is set and the drive circuit (90) is controlled without using the feedback control (S180 to S200). This configuration enables size reduction in the electromagnetic valve by combining the pressure adjusting valve and electromagneticpump into one unit, while sufficiently exhibiting the performance of the pressure adjusting valve and the performance of the electromagnetic pump.