Engine balancer driving mechanism

Claim 1

A four cylinder in-line engine comprising a front wall, a crank-shaft, at least one auxiliary mechanism, a balancer driving mechanism of the type which includes at least one pair of balancer shafts disposed at desired spacings on the opposite sides of the plane including longitudinal axes of said cylinders and substantially in parallel with said crank-shaft axis, said balancer shafts being rotated in the opposite directions to each other at twice the rotational rate of the crank-shaft of the engine, and one of said balancer shafts which is disposed at the lower side of said longitudinal cylinder axes being rotated in the opposite direction to the crank-shaft, a plurality of rotating means mounted, respectively, on a driving shaft of said auxiliary mechanism, on said crank-shaft, and on the balancer shafts, and endless drive means engaging all of said rotating means, and wherein said rotating means mounted on one of the balancer shafts is in engagement with the inner periphery of said endless drive means, and said rotating means mounted on the other of said balancer shafts, is in engagement with the outer periphery of said endless drive means, said engine further comprising a cam-shaft, a rotating means mounted on said cam-shaft and a cam-shaft driving mechanism, said cam-shaft driving mechanism being driven by said crank-shaft and being located in a space between the front wall of the engine and said balancer driving mechanism, said cam-shaft driving mechanism and the front wall of said engine defining a dead space therebetween and said auxiliary mechanism of said engine being located in said dead space.