CONTROL METHOD IN POWER FAILURE

PROBLEM TO BE SOLVED: To provide a control method in a power failure allowing various actions such as cutting work of a machine tool with high precision. SOLUTION: A power failure detection circuit (20) detects a break of an AC power supply (14) to output a detection signal. In response to the detection signal, a controller (24) performs control so that cutting work is continued to finish of the cutting work based on an energy residual amount. A machine tool (10) is provided with a capacitor (18) accumulating energy from the AC power supply (14) and regenerated energy as electric energy. The controller (24) finds a total sum of the electric energy accumulated in the capacitor (18) and kinetic energy of a motor (32) performing cutting work as the energy residual amount. COPYRIGHT: (C)2006,JPO&NCIPI