Numerical control of machine tools

摘要

PURPOSE:To ensure the stable working accuracy by correcting a command locus designated by a working program based on an allowable locus error inputted previously and at the same time correcting the feed speed based on the information obtained by detecting the corrected command locus and the position of a drive part. CONSTITUTION:A command locus Pc is corrected based on the position correction value Dc and a new command locus Pex is calculated. This new locus is sent to a function generating part 5 and also to a command form evaluating part 4'. The form data SD' is calculated based on the locus Pex. While a feed speed correcting part 9' calculates an allowable follow-up delay amount with which the locus error is kept within the value obtained by adding an allowable locus error Et and the value Dc together based on the data SD'. At the same time, the part 9' calculates an actual follow-up delay amount based on the shift value DELTAf set per unit time outputted from the part 5 and the detection value Pa given from a position detector 8. Furthermore the part 9 corrects the feed speed Ft so that the actual follow-up delay amount is kept within the allowed follow-up delay amount and calculates a new command feed speed Fex.