Interference determination method and interference determination device for machine tool

An interference judgment method of a machine tool for judging a presence or absence of an interference between components of a machine tool when operating the machine tool according to a machining program, comprising:

• a setting step of setting a machine tool model obtained by combining shape models of the components, the machine tool model including a workpiece model corresponding to a workpiece;
• a measurement step of measuring the workpiece mounted to a workpiece mounting part to determine a parameter relating to a workpiece coordinate system of the workpiece mounted to the workpiece mounting part, and comparing the determined parameter of the mounted workpiece to a parameter relating to the workpiece coordinate system of the workpiece in the machine tool model set at the setting step to determine a deviation between the determined parameter of the mounted workpiece and the parameter of the workpiece in the machine tool model;
• a correcting step of reading the deviation determined at the measurement step at a predetermined timing and moving the workpiece model set at the setting up step by translation or rotation with an amount corresponding to the deviation to correct the machine tool model set at the setting step;
• and a judgment step of judging the presence or absence of the interference between the components based on the machine tool model corrected at the correcting step and, when judging that the components interfere, operating the machine tool so as to avoid that interference.