Automated microfluidic balancing system for high speed air-bearing spindles

Abstract

The precision balancing of high speed air-bearing spindles is a delicate process. Due to the low bearing stiffness and the quadratic correlation between angular velocity and centrifugal force, the balancing is usually done manually. In order to prevent damage of the air bearings, multiple iterations for different spindle speeds, up to the working rotational speed have to be conducted, resulting in a time-consuming manual balancing procedure with a loss of accuracy for ultraprecision High Performance Cutting (HPC). In this paper, a novel precision balancing system for automatic balancing of high speed aerostatic spindles based on microfluidic valves is presented. In comparison to manual balancing, the system enables a reduction of balancing time to one third and a rise in balancing accuracy. Due to the remotely controlled microvalves, shifts of the center of mass up to two orders of magnitude more precisely than those achieved with conventional manual balancing operations can be attained.