An Analysis of Factors Used for Strength Rating Helical Gears

This paper discusses the factors used to rate the strength of helical-gear teeth by means of the fundamental tooth-strength formula developed by the American Gear Manufacturers Association's Gear Rating Committee. The new approach combines different concepts of geometry factors, an improved evaluation of dynamic loads, rational allowable stresses, and risk or reliability considered as a statistical probability. In addition, the inclusion of the effect of operating error and load-distributing tooth flexibility provides the gear engineer with a more accurate means for helical-gear strength rating. AGMA Fundamental Stress Formula THE basic equation for the bending stress in a gear tooth i