Development of a high-speed mirror-like finish polishing technology for minute parts based on a linear motor

As high speed, high acceleration and stable drive on machine tools is constantly growing in demand, the use of linear motors in machine tools has increased. On the other hand, in order to achieve a high degree of quality, the need for mirror-like finish surfaces on industrial products has also considerably increased. This research explores the use of linear motors to develop a high-speed fine polishing process that achieves a mirror-like finish surface on small parts. The first stage of this process consisted in developing a polishing device, which was composed of a NC milling machine, a linear motor drive and a polishing head. Specifically, a polishing head attached to a linear motor drive was coupled with the spindle of a NC milling machine. A substitute for a small linear motor drive was obtained from a commercially available shaver, while the polishing head was made of propylene. The polishing head elaboration process, linear motor drive properties, lapping agent and the optimum polishing conditions were investigated in several experiments. The evaluation consisted in the high-speed polishing of minute areas on flat surfaces using the selected optimum conditions. It is concluded that, (1) the proposed system was able to achieve a mirror-like finish surface, (2) when compared to polishing with an ultrasonic motor, the machining time of the proposed system was reduced by half, (3) the proposed system was able to achieve a mirror-like finish on a 3 mm square sided area.