Intelligent-speed-increasing Spindle Using Traction Drive

INTRODUCTION Recently, a milling for die using a small end mill of diameter less than 1 mm is increased, because sizes of plastic mold parts such as connectors for an IT and an electronics becomes micro extremely. In general, a tool life is long and a good cut surface is obtained as a cutting speed is high. A speed-increasing spindle, which is attached to a shank may be used to increase the cutting speed to achieve a high-speed cutting in an ordinary machining center (MC). Those using planetary gears [1] or a traction drive [2] that has a future of low vibration and high-accuracy power transmission comparing with a gear have already developed and marketed. In this research, the speedincreasing spindle using a traction drive applying a wedge action (WTD) different from the commercial type is developed to realize a highaccuracy milling, and its performance is evaluated by cutting tests.