Profile Modification

an operation in the manufacture of gears. Profile modification involves removing part of the face of the gear tooth; it is designed to reduce errors in the regular arrangement of teeth on the gear, which give rise to additional dynamic loads and increase vibrations and noise in the gear train. Errors in manufacture and errors arising from deformation of teeth lead to contact of the teeth outside the pressure line, accompanied by a shock. Profile modification eliminates this and ensures theoretically correct contact on the pressure line. The modified profile of a gear tooth is shown in Figure 1.

Figure 1. Profile modification: (1) height of modified section, (2) depth of modification, measured along the normal, (3) modified section of the profile, (4) unmodified section of the profile