Logarithmic Spiral and its Application to the Design of the Relieving Shaped Milling Cutter

From the definition of logarithmic spiral and its particular characteristics, logarithmic spiral is discussed and adopted as the tooth back curve of the relieving shaped milling cutter under the new manufacturing conditions. Thus, the relief angle of each point on the cutting edge keeps instant after regrinding the cutter and thereby makes for preserving the machinability stability. Besides, cutter structure parameters determine coefficient values in the equation of logarithmic spiral tooth back curve. Based on the objected-oriented thought, a CAD system for the relieving shaped milling cutter with logarithmic spiral tooth back is developed in virtue of the language of VBA embedded in AutoCAD, which achieves the automatic generation of logarithmic spiral, realizes the cutter parametric design, shortens the whole cycle and improves the design quality.