CONTROL METHOD OF PROFILE MEASURING APPARATUS

摘要

During a retraction where a stylus tip separates from a work piece from a state where the stylus tip and the work piece are in contact, whether there is contact between the stylus tip and the work piece is monitored. When the contact between the stylus tip and the work piece is detected during the retraction, a probe is displaced to a position where the stylus tip does not come in contact with the work piece and a recovery process is executed. When a distance between a point on a surface of the work piece at a retraction start point and a contact point between the stylus tip and the work piece is Lm, and a value defined by (Lm−d) multiplied by a coefficient k (0

主权项

1. A control method of a shape measuring apparatus including a probe having a stylus tip at a forefront end and a displacement mechanism displacing the probe, detecting contact between the stylus tip and a surface of a work piece, and measuring a shape of the work piece, the method comprising:
when executing a retraction separating the stylus tip from the work piece from a state in which the stylus tip and the work piece are in contact:
obtaining an offset amount Ls between a final command position Pn and a final positioning point Pn′ corresponding to the final command position Pn;comparing the offset amount Ls to a designated retraction length LR designated in advance,executing the retraction with the designated retraction length LR when Ls<β·LR is met,executing the retraction with an error avoidance retraction length Lr′ which is defined at a value shorter than the designated retraction length LR when Ls<β·LR is not met, andβ is 0<β<1.