MACHINING DATA CALCULATING METHOD OF FREE CURVED SURFACE AND MANUFACTURING METHOD OF FREE CURVED SURFACE

摘要

PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing a free curved surface by preventing patternizing of machining marks.;SOLUTION: In this machining data calculating method, the free curved surface is cut by rotating a workpiece around a Z-axis and moving a cutting tool 10 in an X-axis and a Z-axis direction. When the rotation of the workpiece is replaced with the movement of the cutting tool 10, the movement orbit of the cutting tool 10 on a reference surface 18 becomes a spiral S. When a polar coordinate by an angle of rotation θ(°) from a radius vector r and the X-axis is taken on the reference surface 18, the spiral S is expressed by r=r₀+d(2π/360)*θ (however, d is negative). When the coordinates of a machining point n, a next machining point n+1 are considered as (r_n, θ_n), (r_n+1, θ_n+1), respectively, "r_n+1=r_n+Δr", "θ_n+1=θ_n+Δθ" are correlated with each other, and the coordinate of the next machining point n+1 is decided sequentially by using both of the coordinate of the last machining point n and a pseudo-random number with its value changed in a fixed range.;COPYRIGHT: (C)2009,JPO&INPIT