ANCA is Granted U.S. Patent for New Motor Temperature Control Technique
New MTC technique offers dramatic improvement in CNC machine tool stability
Introduction
Melbourne Australia based machine tool builder ANCA has been granted a U.S. patent for Motor Temperature Control (MTC), a technique that dramatically improves the stability of precision machine tools.
Problem to be solved
A key element of machine tools is the spindle which holds and drives the cutting tool which machines the workpiece. Any dimensional errors in the spindle will be reflected as dimensional errors in the workpiece. A common technique in modern machine tools is to use motorized spindles where the driving motor is an integral part of the spindle. ANCA’s patent is a way of maintaining the motorized spindle at a constant temperature. A significant problem in the use of precision machine tools is the impact of changes of temperature particularly in the temperature of the spindle. Changes in temperature of the machine tool can be caused by changes in ambient temperature, coolant temperature, run time, spindle rpm and spindle load.
Solution
ANCA’s solution is to actively control spindle temperature by varying the electrical losses in the motor element while simultaneously maintaining spindle motor speed and load. This is accomplished by using special firmware in the spindle drive amplifier. Although simple in concept, this in practice is a major step forward in manufacturing technology.
