Thermal Instability in High-Speed Gearing

Abstract

Thermal-expansion effects in gearing have usually been considered from a steady-state point of view. A theory of thermal instability is developed which takes into account the tendency of the thermal effects to be regenerative. This theory provides an adequate and complete explanation for several previously unexplained cases of tooth failure in high-speed high-horsepower reduction gears. Experimental verification of the theory is presented and some of the conditions for avoiding thermal instability are described.