Numerical control apparatus having memory storage for machine patterns, plural individually selectable remachining patterns, and control parameters

A control apparatus for a grinding machine wherein a tool support and a work table are movable by first and second feed devices respectively in first and second directions so as to successively grind a plurality of portions of a generally cylindrical workpiece rotatably carried on said work table, said control apparatus comprising:

• first storage means for storing a numerical control program which is prepared for successively grinding said plurality of portions of said workpiece;
• second storage means for storing a plurality of regrinding operation programs each defining a grinding cycle pattern which includes cut-in feed movement and 2 axis movement along a single path of a grinding wheel rotatably carried on said tool support for regrinding one of said portions of said workpiece;
• third storage means corresponding only to a specific portion of the workpiece which is to undergo regrinding and for storing program designation data designating one of said regrinding operation programs and parameters which are required to move said grinding wheel a desired distance at a desired cut-in feed rate when said tool support and said work table are to be moved simultaneously in accordance with a designated one of said regrinding operation programs;
• data input means for manually inputting said program designation data and said parameters for storage in said third storage means;
• position setting means including a manually operable pulse generator for moving said tool support and said work table to position said grinding wheel to a start position at which a cut-in feed of the grinding wheel is executed in relation to said specific portion of the workpiece which is to undergo regrinding;
• and
• feed control means connected to said first and second feed devices and responsive to a grinding start command for controlling operations of said first and second feed devices in accordance with said numerical control program stored in said first storage means, so as to successively grind said plurality of portions of said workpiece, said feed control means being also responsive to a regrinding start command for controlling said first and second feed devices in accordance with said designated one of said regrinding operation programs and said parameters stored in said second and third storage means so that immediately after regrinding of said specific portion of the workpiece, the grinding wheel is removed from the workpiece and the regrinding operation is completed.