Entrance Angle of Top Cutting Edge in Hobbing.

Abstract

The entrance angle of hob teeth greatly depends on hob design, gear design and cutting conditions. This exerts serious influence upon damage to the hob. If the entrance angle is small, the cutting edge slips easily at he beginning of cutting, and damage (chipping and flank wear) is increased. Therefore, it is important to grasp how the entrance angle changes, in the case of hob design and selection of hobbing conditions. The authors report the value of an entrance angle that depends on module, hob diamerter, number of flutes, number of threads, number of gear teeth, helix angle and hobbing method clarified by calculation.