| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive structure capable of preventing variation in a lead of a thread part to be formed, due to heat expansion during processing a work-piece 19a.SOLUTION: A memory device 22 is provided to store a heat expansion amount with respect to an axial direction of a work-piece 19a, measured by measurement means 13. A control device 17 has a function of setting a rotation speed of a rotation drive shaft 11 or a feed speed of an axis-direction feed device 16a for a work-piece 19a, which should be processed next, on the basis of history information of the heat expansion amount stored in the memory device 22. |
