Anti-rattle engine balancer which drives associated oil pump

摘要

A Lanchester type engine balancer avoids rattle of gears connecting counterrotating balance shafts by minimizing inertia through limiting diameters of the counterweight envelopes, timing gears and bearing journals of the balance shafts and by driving an accessory, such as an oil pump from the driven balance shaft. Gear lash is controlled by using a cast iron housing with select fitting of steel gears. Also maximum gear pitch diameter runout is oriented in assembly opposite the counterweights of the respective balance shafts to minimize a change in lash caused by shaft runout due to the eccentric load of the counterweights during operation.