Data processing device for three dimensional surface machining

A data processing device for machining a three dimensional surface by using a tool having a plurality of various curvature machining portions, one of which is selected in response to variations of the curvature on the three dimensional surface comprising:

• (a) means for calculating information for expressing the three dimensional surface based on factors of the three dimensional surface;
• (b) means for generating tool locus data
• (i) by providing tool shape and dimension indicative information and machining route information,
• (ii) by calculating at least one information selected from a curvature, a normal line and a tangential line of the three dimensional surface to be machined, based on said calculated information for expressing the three dimensional surface at each machining point, said tool shape and dimension indicative information and said machining route information,
• said three dimensional surface being machined by the tool having various machining portions, where a graphical projection of an outermost locus of motion of the tool, located on a plane parallel to the longitudinal axis of the tool, has a shape comprising at least one curve whose curvature is changed, and
• (iii) by calculating a shape condition and/or a controlling condition of the tool based on said at least one information;
• (c) means for checking the tool locus data based on a predetermined pattern;
• and
• (d) means for converting the tool locus data into data to be inputted into a machine which conducts three dimensional surface machining.