Early closing miller cycle internal combustion engine

The present invention mitigates restriction due to the fact that the opening period (angular working range) of the intake valve becomes smaller in the early closing Miller cycle operation, in which the intake valve closing timing occurs before the bottom dead center. The crankshaft center O1 is offset on one side from the cylinder central axis X. The top dead center and the bottom dead center of the piston occur when the three points, namely the crankshaft center O1, the crankpin center O2, and the piston pin center O3 are aligned in one line. At this time, the connecting rod and the crank arm are inclined relative to the axis X. The inclination angle thetabdc at the bottom dead center is greater than the inclination angle thetatdc at the top dead center. Therefore, as the crankshaft rotates in the direction of arrow omega, the intake process and the expansion process become greater than 180° CA, while the compression process and the exhaust process become smaller than 180° crank angle. Accordingly, the angular working range of the intake valve is enlarged. Therefore, the restriction to the valve lift curve is mitigated.