NC device controlling machining processes with pre- and post-execution in-position values

摘要

A numerical control device can perform machining processes in a short time while maintaining high precision, regardless of the order at which programs are commanded. Consecutive blocks of a numerical control program are retrieved on a block-by-block basis, and a pre-execution in-position value and a post-execution in-position value for each of the blocks of the numerical control program are set and stored in a ROM. The block of the numerical control program is executed in accordance with at least one of the corresponding pre-execution in-position value and the post-execution in-position value. In one embodiment, if the post-execution in-position value of a formerly retrieved block is large and the pre-execution in-position value of the subsequently retrieved block is small by retrieving two consecutive blocks, the post-execution in-position value of the formerly retrieved block is rewritten to a small value, and the block of the program is executed in accordance with the rewritten post-execution in-position value.