Patent ID: 7194990

Claim:
Hydraulic actuator for an internal combustion engine valve, comprising: a fluidic actuation chamber, defined in part by an actuation piston and characterized by increasing chamber volume as the actuation piston is urged away from a neutral position, and, having a high pressure fluid inlet, and, a fluid outlet; a fluidic actuator control chamber, defined in part by a control piston operably connected to the actuation piston, and characterized by increasing chamber volume as the actuation piston is urged away from the neutral position, and, having a control fluid outlet; a fluid control valve, comprising a spool valve having a fluidic control chamber fluidly connected to the control fluid outlet of the fluidic actuator control chamber; the fluid outlet of the fluidic actuation chamber fluidly connected to an inlet of the control valve; and, a valve actuation plunger, operably connected to the actuation piston.