Spline shaft hob cutter accuracy increase by the means of theoretical profile approximation by the circle involute section

Abstract

One of the most wide spread and efficient spline shafts manufacturing methods is their cutting by the means of generating process by hob cutters. In this case, hob cutter’s theoretical profile, taking in to account its inadaptability to manufacture, traditionally is approximated by the section(s) of one or two circles. In some cases this approach do not provides necessary accuracy or increase complexity of the manufacturing process. Alternative to the traditional approximation approach is theoretical profile substitution by the circle involute section. Absence of the methods for circle involute parameters evaluation makes this work relevant. There is approach suggested for this kind of substitution, based on equality of theoretical profile’s and substituting curve’s curvature radii in rated points. Methods and algorithms for substituting circle involute parameters and substitution accuracy evaluation are suggested. Given evaluation result shows more than 20 times higher approximation accuracy in comparison with the circle section substitution.

Keywords

• linear-form spline shaft
• hob cutter
• theoretical profile
• substituting circle
• circle involute
• coordinate system shift
• sweep angle
• basic circle
• approximation accuracy