V-TYPE INTERNAL COMBUSTION ENGINE WITH AN UNLIKE NUMBER OF CYLINDERS

摘要

An odd-cylinder V-type internal combustion engine including 2n+1 cylinders (n is a natural number) arranged in two banks and pistons fitted in the cylinders has a crankshaft provided with n common crankpins (KC) each connected to the two paired pistons respectively belonging to the two banks, and one odd crankpin (KS) connected to the one unpaired piston. The common crankpins (KC) are disposed at the same phase. Bank angle between the two banks meets = cos-1(1/2n). The odd crankpin (KS) is disposed (180-) DEG behind the common crank pins (KC) with respect to the rotating direction of the crankshaft when the unpaired piston belongs to the front bank with respect to the rotating direction of the crankshaft. Reciprocating parts including all the pistons fitted in the cylinders have the same mass (M), and the crankshaft is provided with balance weight means capable of generating a balancing force of kMr omega 2 acting in a sense of ( alpha +180) DEG , where: DFk= SQRTSQUARE1 DIVIDED 2 SQRT1-1 DIVIDED 4n2/SQRT/SQUARE + (n-1 DIVIDED 4n)2/SQRT /DF MATH alpha : Angle from the common crankpins in the rotating direction M: Mass of each reciprocating part r: Crank throw omega : Angular velocity of the crankshaft ??The odd-cylinder V-type internal combustion engine prevents generation of a primary vibration caused by a primary inertial force without entailing increase in weight and size. IMAGE