Development of a Secondary Balancer for an Existing Diesel Engine

A Lanchester type secondary balancer for an existing 4 cylinder Diesel engine was developed to control the excessive vibration of a 3.5 ton class lift truck. Because the number of teeth on the crankshaft gear of the engine was an odd one, an intermediate gear-shaft system was used between the original timing gear train of the engine and the secondary balancer in order to drive the latter at twice the speed of the crankshaft.

A prototype of the balancer was built and tested to verify its effectiveness on the elimination of the second order harmonic excitation of the engine. Among the vibration modes, the heaving motion which was caused by the operation of the slider-crank mechanism of the engine was successfully reduced using the secondary balancer.