USING THE JACOBS GEAR HOBBING MACHINE TO CUT HELICAL GEARS 2

摘要

The following describes how to determine the gear sets on the corrective train and the feed train to hob a specific helical gear with acceptable accuracy. When cutting a spur gear, for example of 20 teeth, the rotation of the workpiece must be 1/20th of a revolution for each revolution of the hob (assuming the hob is in the form of a single start worm which is generally the case) i.e. an index gear ratio of 20:1 is required between the hob and the workpiece.