With structure comprising a cylinder, a magnetic circuit to exert a
mountain-shaped thrust, and a feeding spring to exert an urging force to
a plunger during a feeding process, fuel is sucked by movement of the
plunger and energy is accumulated in the feeding spring during a powering
state, the fuel is fed by movement of the plunger by the urging force of
the feeding spring during a non-powering state, a spring constant of the
feeding spring is set to generate an urging force larger than a thrust in
an early range of the mountain-shaped thrust, and a second spring is
disposed to exert an urging force in a direction against the urging force
of the feeding spring to make the urging force smaller than the thrust,
at least in the early range. In this manner, with an electromagnetically
driven type plunger pump of a non-powering feeding type, an effective
stroke is enlarged and a feeding amount is increased.