Patent ID: 8539917

Claim:
A variable compression ratio apparatus for an engine receiving combustion force of an air-fuel mixture from a piston and a rotating crankshaft, and which changes compression ratio of the air-fuel mixture, the variable compression ratio apparatus comprising: a connecting rod including a small end and a big end, the small end being formed of an eccentric bearing hole concentrically rotatably connected to the piston through a piston pin, and the crankshaft is rotatably mounted at the big end; an eccentric link including one end supporting an eccentric bearing rotatably mounted in the eccentric bearing hole, an eccentric link slot extending along a longitudinal direction thereof; a variable bar including a variable bar gear at one end, and connected to the eccentric link by a variable bar pin movably received along the eccentric link slot; and a variable gear engaged with the variable bar gear to reciprocally move the variable bar to a predetermined direction; wherein the eccentric bearing includes an eccentric piston pin hole, and the piston pin is inserted in the piston pin hole rotatably interconnecting the piston, the connecting rod, and the eccentric link.