Tool path data generation apparatus for NC machine tool and numerical controller provided with it

In an NC machine tool, a tool path data generation apparatus for automatically generating tool path data including position data on where to transfer a tool and cutting conditions for the tool, the tool path data generation apparatus comprising:

• a feature data extractor for extracting, on the basis of CAD-device-created geometry data on a workpiece to be machined by the machine tool, at least feature data relating to the three-dimensional final form of the workpiece;
• a tool/cutting data storage for storing data including cutting-mode and tool information determined by the extracted feature data, and cutting-speed and depth-of-cut information determined by the material of which the workpiece consists;
• a cutting method determining unit for determining an optimal cutting method for each of the final-form features of a workpiece, on the basis of the extracted feature data, and on the data stored in the tool/cutting data storage;
• a tool path data generator for generating tool path data on the basis of the cutting method determined by the cutting method determining unit;
• and
• a machining information generator for generating, on the basis of the cutting method determined by the cutting method determining unit and on information stored in the tool/cutting data storage, machining information including tool consumption to machine to final form, estimated time to tool wear-out, and estimated time to machine to final form.