Estimation of Critical Section and Bending Stress Analysis for Asymmetric Spur Gear Tooth

摘要

Gearing is one of the most critical components in mechanical power transmission systems. Transmission error is considered to be one of the main contributors to noise and vibration in a gear set. Transmission error in the gear leads to backlash, undercut and interference. These defects can be eliminated by increasing the pressure angle. Backlash and interference can be avoided by Increase addendum of mating gear; another way of increasing the load capacity of transmissions is to modify the involute geometry. This has been a standard practice in sophisticated gear design for many years. The nomenclature describing these types of gear modifications can be quite confusing with reference to addendum modification or profile shift, etc. An additional alteration that is very rarely used is to make the gears asymmetric with different pressure angles for each side of the tooth. This is because two profiles of a gear tooth are functionally different for most of the gear drives. The workload on one side of profile is significantly higher than the other side of the gear. An asymmetric spur gear drive means that larger and smaller pressure angles are applied for the driving and coast sides. The main objective of this paper is to generate asymmetric spur gear tooth profile for different pressure angles on drive and coast sides and estimate the critical section using C-programming. Bending stress analysis has been performed using finite element analysis using ANSYS software. Comparison of bending stress analysis has been performed for symmetric and asymmetric spur gear tooth at critical section.