The electromagnet includes a valve-opening side coil portion supplied with a current to thereby generate a first magnetic flux and generate electromagnetic force in a direction moving the valve-opening side moving element toward a valve-opening position, and a valve-closing side coil portion supplied with a current to thereby generate a second magnetic flux and generate electromagnetic force in a direction moving the valve-closing side moving element toward the valve-closing position. The valve-opening side coil portion and the valve-closing side coil portion are constituted of an identical connection. The electromagnet further has a sub-coil constituted of a separate connection from the valve-opening side coil portion and the valve-closing side coil portion. By the current supply to the sub-coil, a third magnetic flux reducing at least one of the first magnetic flux and the second magnetic flux is generated.