Machining, Measurement, and Control Laboratory

Measurement of Spindle Stiffness by using a Magnet Loader
Taku Yamazaki, Atsushi Matsubara, Tomoya Fujita, Toshiyuki Muraki

In this paper a method for measuring the static stiffness of rotating spindle is presented to evaluate the performance of the rotating spindle of machine tools. A magnet-loading device is adopted as the equipment for loading to the rotating spindle, which can load the tool with non-contact condition. The attraction force induce by the supplied current of the device are measured to investigate the effects of the gap between the loaded tool and the loader as well as the spindle speed on the current-force relationship. As the result, it is found that the gap distance is dominant to control the attractive forces. Measurement of the spindle stiffness is demonstrated by using the developed loading device and measurement system.
Key Words: Machine tool; Spindle; Static stiffness; Non-contact measurement; Magnet loader; Displacement