Machine crank-shaft with improved dynamic balance ratio

摘要

A balanced multiple-throw crank-shaft wherein the free forces of the first and second orders forming resultants for the whole crank- shaft of the forces produced by each coupling are substantially zero and at least some of the crank-throws are shifted or offset angularly, respectively, by such a small angle in one direction of rotation and by such an amount relative to the corresponding circumferentially uniformly distributed angular positions they would assume in a configuration with angularly equally spaced crank-throws in orthogonal projection on a plane perpendicular to the geometrical spin axis of rotation of said crank- shaft that an improved balancing ratio will result therefrom.