Pressure-storage type fuel injection device for internal combustion engines

A fuel injection device is so constructed that fuel fed from a pressure storage chamber to a valve housing with a nozzle is led to a needle valve back pressure chamber through a groove provided on the peripheral surface of a needle valve; a fuel pressure in the back pressure chamber is controlled by opening and closing a pressure regulating port provided in the valve housing by a pilot valve so as to move the needle valve, whereby the nozzle is opened and closed. The pressure regulating port is opened and closed by a drive control of the pilot valve with a valve drive unit by means of elongation and contraction of the magnetostrictive rods attributable by the action of an external magnetic field. The magnetostrictive rods, consisting of first and second magnetostrictive rods (and ), are axially arranged side by side in parallel to the pilot valve.