Patent ID: 8733302
Filing Date: 2014-05-27
Classification: F02B,Y10T

Abstract:
1. A variable compression ratio apparatus mounted in an engine to change a compression ratio of mixed gas, comprising: a crankshaft configured to switch reciprocal movement of a piston by combustion power of the mixed gas to rotary movement; a connecting rod having one end in which a piston pin is inserted to be rotatably connected to the piston through the piston pin, and the other end rotatably connected to the crankshaft; first and second eccentric links mounted at both sides of the connection rod, respectively, and having one ends at which the piston pin is eccentrically and rotatably installed; a swing link of which one end is branched into two parts to form first and second branches, the first and second branches being connected to the other ends of the first and second eccentric links; and a control device connected to the other end of the swing link to control the swing link; wherein the crankshaft includes a crank journal rotatably supported by a cylinder block crank pin to which the other end of the connecting rod is rotatably connected, and a crank arm configured to connect the crank journal and the crank pin; wherein the crank arm includes guide surfaces formed in a predetermined thickness at an inner circumferential surface of the crank arm so that the first and second branches of the swing link move between the guide surfaces; wherein each of one ends in the first and second branches is provided with branch portions divided into two parts; and wherein each of the other ends in the first and second eccentric links is inserted in the corresponding branch portions to be rotatably connected thereto.