| 摘要 |
PURPOSE:To reduce processing time by controlling, at the time of drilling on a numerical control machine tool, in such a manner as cutting feed speed at cutting starting time and work penetration time is slower than medium cutting time and reducing excessive load on the drill. CONSTITUTION:Processing starting point STP, processing completion point ENP, positions of coordinates for the surface 15a and the reverse 15b, standard feed speed and the like for a work 15 are stored in a processing program, while early rush distance L1, final distance L2 and coefficient of correction for the standard feed speed of a drill 16 are also stored in a memory. At the time of processing, points PT1, PT2 corresponding to the early rush distance L1 and the final distance L2 are set with respect to the work 15, while a section from the processing starting point STP up to the processing completion point ENP is divisionally set into the first section K1, the second section K2 and the third section K3. Then a cutting feed speed of the drill 16 in each section is corrected to the standard feed speed on the basis of coefficient of correction in the memory, and the first and third sections K1, K3 are controlled to the speed lower than that of the second section K2. |
