Numerical control method

A numerical control method for positionally controlling the movable element of a machine tool in such a manner that numerically controlled machining is performed along a projected path obtained by projecting a programmed path, lying on a predetermined plane, onto a plane of projection inclined at a predetermined angle with respect to the predetermined plane, said method comprising the steps of:

• (a) entering path data specifying a programmed path on the predetermined plane and projection angle data specifying the predetermined angle;
• (b) subjecting the path data entered in step (a) to a projective transformation in accordance with the entered projection angle data to generate projective transformation data specifying the projected path;
• and
• (c) performing an interpolation on the basis of the projective transformation data to produce an output signal indicative of the results of the interpolation, and positionally controlling the movable element on the basis of the projective transformation output signal.

A numerical control method for positionally controlling a movable element of a machine tool based on path data for a predetermined plane, said method comprising the steps of:

• (a) providing a projective direction angle and projection angle data specifying a projection of the path data onto a projection plane;
• (b) transforming the path data for the predetermined plane into path data for the projection plane in dependence upon the projective direction angle and projection angle data;
• and
• (c) controlling the movable element in dependence upon the transformed path data.