VARIABLE VALVE LIFT APPRATUS

摘要

The present invention relates to a variable valve lift device capable of changing a valve lift using a cam. The variable valve lift device, which changes the lift of an intake valve or an exhaust valve into at least two or more stages, according to an embodiment of the present invention includes: a lever body which is formed at a predetermined length in order to perform a lever movement by the rotation of the cam and is connected with the intake valve or the exhaust valve at an end; a piston which is installed to be able to reciprocate in the longitudinal direction of the lever body; a cylinder which accommodates the piston so that the piston reciprocates inside and is mounted in the lever body; a hydraulic chamber which is a space formed between the inner surface of the cylinder and an end of the piston in the cylinder; an operation unit which is installed to move with the piston in one united body; a hinge unit which is connected with the operation unit by a hinge; a roller which is connected to the hinge unit in order to be rotatable and moves in the longitudinal direction of the lever body by the reciprocating movement of the piston; a rotary shaft which is the rotation center of the roller, is installed to penetrate the hinge unit and the roller, and moves with the roller; a guide hole which is formed in the lever body so that the rotary shaft is inserted and guides the movement of the rotary shaft; a hydraulic supply unit which supplies a hydraulic pressure to the hydraulic chamber in order to operate the piston in the direction of the other end of the lever body; and a spring which returns the piston to the original position if the hydraulic pressure supplied to the hydraulic chamber is released.