Dynamic balancing of swash plate pump - by moving balance weights to maintain balance at varying swash angle

摘要

A hydraulic swashplate plump or motor plate is dynamically balanced by varying the eccentricity of the end bearing of the crankshaft. This results in an increasing degree of dynamic unbalance with increasing swash angle. To overcome this problem the sliding bearing which supports the end of the crankshaft is provided with two symmetrically arranged hinged racks which mesh with pinions which in turn mesh with quadrants forming the balance weights. As the bearing moves outwards from the centre the balance weights rotate in opposite directions so that their combined centre of gravity moves outwards in the opposite direction to the bearing.