Extending the capabilities of the Jacobs Gear Hobber

摘要

The Jacobs Gear Hobbing Machine has been around for at least 40 years and is still available as a set of castings and drawings from College Engineering Supply1 as a home workshop project. Designed originally by Tom Jacobs and featuring in a series of Model Engineer articles in 1976, it was intended more to demonstrate the process and principles of gear hobbing than as a production machine. I built my mine in 2009 and with the plans available the machine is intended to make spur gears only. Photograph 1 (Yes, the universal joints on the cardan shaft are incorrectly aligned. I was careless in the assembly for the photo.) shows it set up in its standard form to hob a spur gear. However, I was fascinated with the idea of making helical gears as well as spur gears.