Contact Stress Analysis of Modified Straight Bevel Gear
The straight bevel gears are important mechanical element used in the industrial application for the purposes of transfer power and motion from one part to another. Therefore, this study aim to increase the capability of the teeth to resist pitting failure and increase life of gears by modified the teeth profiles of standard (symmetric) straight bevel gear. The modification used in this study involve adopted the pressure angle of the teeth profile on unloaded side and fixed the pressure angle of the teeth profile on loaded side to established a new geometry of modified (asymmetric) straight bevel gear . The first step used in the contact stress analysis is the generation of the tooth profile of standard and modified straight bevel gear, this generation process has been done by using SOLIDWORKS program (ver.14) according to the parametric equation describe the movement of the cutter. Then numerical investigation was done on the model of the standard and modified straight bevel gear by using Finite Element Method (FEM) based on the ANSYS program (ver.16) to find the value of the contact stress. The results obtained from this study explained that there are a good enhancement in the value of the contact stress when using the modified straight bevel gear instead of standard case. These enhancements in the value of the contact stress explain good for the case of modified straight bevel gear with unloaded pressure angle 350 with enhancement percentage about 19.601%. Finally, verification on the numerical results of the contact stress has been done only for standard straight bevel gear by using analytical equation.