Patent ID: 7699242

Claim:
An injector comprising: a piezoelectric actuator that causes displacement when voltage is applied thereto; a pressurizing piston that moves in an axial direction in accordance with the displacement of the piezoelectric actuator; a cylindrical movable sleeve that moves in the axial direction with the movement of the pressurizing piston; a valve body that has an injection hole in an axial tip end portion thereof for injecting a high pressure fluid; a needle that is slidably held in the valve body and that opens and closes the injection hole; a pressure control chamber that stores control pressure concerning the opening/closing action of the needle and that is provided such that the control pressure in the pressure control chamber is increased or decreased by the movement of the movable sleeve; and a lift limiting member that limits a valve opening lift position of the needle, wherein the control pressure of the pressure control chamber is increased or decreased to control the opening/closing action of the needle, the pressurizing piston has a head section that receives the displacement of the piezoelectric actuator and a transmitting section for transmitting the movement of the head section to the movable sleeve, the needle has a needle head section slidably fitted to an inner periphery of the movable sleeve, the lift limiting member is provided by a single plate member arranged between an axial end face of the needle head section and the head section of the pressurizing piston, and the plate member is formed with a hole section, in which the transmitting section of the pressurizing piston is loosely inserted, and with a stopper face, with which the axial end face of the needle head section contacts when the needle lifts by a predetermined amount.