SPUR Gear Tooth Stress Analysis and Stress Reduction using Stress Reducing Geometrical Features

Abstract

Gears have a wide variety of applications. Their applications vary from watches to very large mechanical units like the lifting devices and automotives. Gears generally fail when the working stress exceeds the maximum permissible stress. Number of studies has been done by various authors to analyse the gear for stresses. Gears have been analysed for different points of contact on the tooth profile and the corresponding points of contact on the pinion. In this study the technology of gears is presented along with the various types of failures that gears have. The causes of these failures are studied and one type of stress related failure due to fatigue failure of a gear tooth due to stress concentration is detailed. Various studies have been done for variation of moment. Studies have also been done to find the highest point single tooth contact. The point after being found is point of application of force. Then the variation stress in root fillet region is found, which is then used for the study of variation of various parameters of stress reducing features. The effect and use of stress relief feature in geometry of gear is studied as reported by researchers. A study of the optimum size and location of the stress relief features for pinion and gear is proposed which help in reducing the fatigue failure in gears.