A Finishing Method of Rotor in Screw Compressor by Fly Tool : 1st Report, an Example of a Circular Arced Tooth-profile

Abstract

The purpose of this study is to finish the helicoidal surface accurately by using a fly tool. A rotor used in a screw-compressor of non-lubrication type is taken as an example of the helicoidal surface. As a fundamental study to manufacture the rotor of non-lubrication type by a fly tool, the cutter shape is numerically analyzed for the helicoidal rotor, having a circular arc in the section perpendicular to the rotor axis. Then the rotor is hobbed with this cutter and measured by a three-dimensional measuring machine. Furthermore, the cutter shape is analyzed for a helicoidal rotor whose section is composed of plural curved lines. As the result, it is made clear that it is possible to manufacture the rotor of non-lubrication type by using a fly tool.