Tool presetter and tool offset amount calculation method

摘要

A tool presetter and a tool offset amount calculation method are provided which ensure easy and accurate determination of reference tool offset amounts in a machine tool having a pivotal tool spindle stock. The tool presetter is mounted in a composite lathe having a pivotal tool spindle stock 17. The tool presetter calculates tool offset amounts Oz (=A-Zm), Ox (=B-Xm) on the basis of machine coordinate values Zm, Xm of the tool spindle stock detected when a nose of a tool T is in contact with Z-axis and X-axis detection points of a presetter sensor 18 with the tool spindle stock 17 pivoted by a pivot angle alpha , and machine coordinate values A, B of the Z-axis and X-axis detection points of the presetter sensor 18, and calculates reference tool offset amounts Lz, Lx from predetermined expressions on the basis of the tool offset amounts Ox, Oz and the pivot angle alpha of the tool spindle stock 17.