Development of a Elliptical Vibration Milling Machine

A unique elliptical vibration milling machine is developed by utilizing a double-spindle mechanism. The developed machine generates circular vibratory motion of the cutting tool mechanically by rotating an eccentric sleeve with a built-in motor. The radius and the maximum frequency of the circular vibration are set to 0.5 mm and 167 Hz respectively. The developed machine is applied to elliptical vibration planing by clamping the tool spindle, and also to elliptical vibration end milling by rotating the inner tool spindle as well at the same time. The machining tests of hardened steel with CBN and coated carbide tools are carried out, and it was proved that the elliptical vibration cutting shows better results as compared with conventional cutting without elliptical vibration motion. A mirror surface on hardened steel with a roughness of about 0.11 μm Ra was obtained by elliptical vibration planing by employing a single crystal diamond tool.