Defination of Basic Hob Profiles

Defination of Basic Hob Profiles

The basic hob profile is the normal sectional profile of an imaginary tooth rack, which meshes with the workpiece teeth under the following conditions: 

1), The basic profile line of the rack rolls on a defined pitch circle diameter of the workpiece. 

2), The pitch of the rack is equal to the pitch on the pitch circle diameter, 

3), Meshing with the workpiece takes place:

Standardized basic hob profiles are shown in: DIN 3972 and DIN 58412 standard