Patent ID: 7063054

Claim:
A valve driving device of an internal combustion engine, to drive the opening and closing of a main valve serving as an intake valve or an exhaust valve of the internal combustion engine, comprising; a pressure chamber to which pressurized actuating fluid is supplied in order to open the main valve; high-pressure actuating fluid supply means for supplying the high-pressure actuating fluid to the pressure chamber during the prescribed interval of the main valve initial opening period; low-pressure actuating fluid introduction means for introducing the low-pressure actuating fluid into the pressure chamber after the prescribed interval of the main valve initial opening period has elapsed; actuating fluid discharge means for discharging the actuating fluid from the pressure chamber in order to close the main valve; the high-pressure actuating fluid supply means comprising a first actuating valve to switch between supplying and halting the supply of the high-pressure actuating fluid to the pressure chamber; the low-pressure actuating fluid introduction means comprising a second actuating valve to switch between introducing and halting the introduction of the low-pressure actuating fluid to the pressure chamber; and the actuating fluid discharge means comprising a third actuating valve to switch between discharging and halting the discharge of the actuating fluid from the pressure chamber; and the first actuating valve comprising a needle-shaped balance valve; a supply passage, facing toward the one end of the balance valve, circulating the high-pressure actuating fluid which is supplied to the pressure chamber, which is opened and closed by the balance valve; a valve control chamber, facing toward the other end of the balance valve, to which the high-pressure actuating fluid for driving the balance valve in the closed direction is introduced; a spring for impelling the balance valve toward the closed direction; an armature for opening and closing an exit of the valve control chamber; and an electrical actuator for driving the opening and closing of the armature in response to the ON/OFF signal.