ODD-CYLINDER V-TYPE INTERNAL COMBUSTION ENTINE

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 &thetas; between the two banks meets &thetas; = cos<-1>(1/2n). The odd crankpin (KS) is disposed (180-&thetas;) 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: k= 1 DIVIDED 2 1-1 DIVIDED 4n<2> + (n-1 DIVIDED 4n)<2> $alpha\; :\; Angle\; from\; the\; common\; crankpins\; in\; the\; rotating\; direction\; M:\; Mass\; of\; each\; reciprocating\; part\; r:\; Crank\; throw\; omega\; :\; Angular\; velocity\; of\; the\; crankshaftThe\; odd-cylinder\; V-type\; internal\; combustion\; engine\; prevents\; generation\; of\; a\; primary\; vibration\; caused\; by\; a\; primary\; inertial\; force\; without\; entailing\; increase\; in\; weight\; and\; size.\mathop{\mathrm{image}}$