Numerical control device

Abstract

A numerical control device for synchronously controlling the movement of a plurality of axes of a machine by repeatedly controlling a cyclic motion. An axis of the machine is designed to stop at a predetermined position upon the occurrence of an emergency stop. To achieve this stop position, an amount of retraction is set up to a position where a tool of machine does not interfere with a work piece or other obstacles. When an emergency stop signal is entered during a binary operation, because of an occurrence of an abnormality, a movement control amount for each period, corresponding to a set amount of retraction, is added to the movement control amount for each period of the binary operation and the axis is thereby driven by the resultant modified movement control amount. The binary operation is stopped upon the reaching of the stop position, and the tool can be held at this retracted position, by the set amount of retraction. Thus, the tool can be retraced to a predetermined position where it does not interfere with either a work piece or another obstacle.

Dependencies are inferred from the claim text.