ABSTRACT
There are two basic methods of manufacturing gear teeth: the generating process and the forming process. Hobbing machines, shaper cutters, shaving machines, and many grinders use this principle. When a gear tooth is formed, the tool is in the shape of the space that is being machined out. Some grinding machines use this principle with an indexing mechanism which allows the gear teeth to be formed tooth by tooth. Shaping can be applied to internal as well as external spur or helical gears. Also, herringbone gears are cut by the shaping process. The shaving cutter is meshed with the work gear in a crossed axis relationship, and rotated while the center distance between the two is reduced in small increments. The grinding operation is strongly influenced by the condition of the gear after heat treatment. This chapter describes some of the specialized instruments available for performing analytical and functional inspections of gear teeth.
