A Study on NC Gear Cutting of Large-size Bevel Gears : 3rd Report; A Method to Save Path Number of the Cutter in Tooth Generation

Abstract

The normal tooth profile of a bevel gear changes its form along the tooth trace. When this profile is generated by an end milling cutter of straight axial profile, the number of cutter paths to generate the tooth will surely become large. If the axial profile is suitably designed and the generating point is properly selected in accordance with the cutter profile relative to the tooth profile, the number of the paths will be reduced greatly. This report proposes a new cutting method based on this idea. It is a procedure to avoid the interference between the profiles and to select the generating points, giving also the unremoved volume on the generated tooth surface. The ratio of the unremoved volume in the case of three cutter paths by the curved profile cutter compared to that by the straight profile cutter is estimated to be about 1/20 for the pitch angle 〓 =15°, and about 1/7 for 〓 =75°.