Variable valve lift device

A variable valve lift apparatus, comprising:

• a rocker arm coupled with a rocker arm shaft;
• a valve bridge disposed to be pressed by one end portion of the rocker arm, wherein the valve bridge includes a piston insertion hole that is open upward and at least one pin insertion hole that connects to the piston insertion hole in a lengthwise direction of the valve bridge;
• a valve disposed to be pressed by the valve bridge;
• a variable lift unit disposed in the valve bridge and variably controlling an amount that the rocker arm presses the valve bridge, wherein the variable lift unit includes:
• a variable piston of which a lower portion is inserted into the piston insertion hole, wherein a pin groove is formed on a side surface of the variable piston corresponding to the pin insertion hole, and a piston oil passage that is connected to the pin groove is formed in the variable piston to selectively receive a hydraulic pressure from the rocker arm;
• and
• a check pin disposed in the pin insertion hole to be selectively inserted into the pin groove of the variable piston according to the hydraulic pressure that is supplied to the piston oil passage;
• and
• a rocker arm elastic member that elastically supports the rocker arm such that the one end portion of the rocker arm presses the valve bridge,
• wherein the rocker arm elastic member is a plate spring, and one end thereof is fixed on the rocker arm shaft and the other end thereof elastically supports one end portion of the rocker arm shaft toward the valve bridge.