A fixed core includes: a fixed core tapered portion having a diameter increased in an attraction direction; and a fixed core circular portion having a fixed outer diameter and extending in the attraction direction from an end of the fixed core tapered portion. A movable core includes a movable core tubular portion in which a movable core hole is defined. The movable core hole is a space into which the fixed core tapered portion and the fixed core circular portion can enter. The movable core tubular portion includes: a movable core cylindrical portion having a constant inner diameter; and a movable core tapered tubular portion having an inner diameter decreased from an end of the movable core cylindrical portion in a non-attraction direction.
