| 摘要 |
PURPOSE:To reduce vibrations of an engine and to obtain a balancer of lightweight and small-size by providing a balancer shaft in parallel with a crank shaft provided with uniform counterweights on individual crank arms and by providing independent balancers at two places of the balancer shaft and halved split balancers at other two places. CONSTITUTION:Counterweights 6a-1, 6a-2; 6b-1, 6b-2; 6c-1, 6c-2 against masses of the reciprocating portion and rotating portion of an engine are uniformly provided on crank arms of the first through third cylinders of a crank shaft 1 provided with the crank arms at a unifirm interval of 120 deg.. One balancer shaft 7 revolving at the same speed and in the opposite direction to the crank shaft 1 is also provided, and balancers 8a, 8c are provided on said shaft 7 at places corresponding to crank shaft bearings 9a, 9d of the first and third cylinders and halved split balancers 8b-1, 8b-2 are provided at places corresponding to bearings 9b, 9c of the second cylinder. |
