NUMERICAL CONTROL APPARATUS FOR CONTROLLING MACHINE TOOL HAVING TOOL BREAKAGE DETECTING FUNCTION

摘要

PROBLEM TO BE SOLVED: To provide a numerical control apparatus for controlling a machine, capable of immediately determining, upon breakage of a tool, the breakage according to the shape of a workpiece.;SOLUTION: The numerical control apparatus 10 for controlling a machine tool having a main shaft and a movable shaft by generating a tool path based on a processing program designating at least material shape information and a cutting quantity includes: a current detector 24, 26 for detecting the load of a servo motor 19 or a spindle motor 22; a position-speed detector 25 for detecting the position of the servo motor 19; and a tool breakage detecting function for determining whether a load current value detected by the current detector 24, 26 is in a no-load state, reading a tool path instruction under execution when the load current value is determined to be in the no-load state, determining whether the tool position is on the inside or the outside of the material shape based on the material shape information, the tool path instruction, and the position information of the servo motor 19, and determining a tool breakage when the tool position is determined to be on the inside.;COPYRIGHT: (C)2010,JPO&INPIT