The design of spiral bevel gears

• Main Author: Yousif, Ahmed
• Published: University of Leeds 2010
• Subjects: 621.8332
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577533

Spiral bevel gears are used widely in the transmission systems of several mechanical applications. The design of spiral bevel gears is very complicated. This is due to the complexity of the gear tooth geometry. This research concentrates on a special type of spiral bevel gears, the Palloid spiral bevel gears. The design methodology is based on the concepts of the machine kinematics. This delivers a numerical model of the spiral bevel gear tooth surfaces. The concept of a three dimensional vector analysis is applied. In addition, the condition of the tangential contact between the meshing surfaces of the cutting tool and gear blank is utilised. This is performed using the mathematical modelling software package MATLAB. The data points of the gear tooth surfaces obtained from MATLAB are defined as the nodes of the finite element mesh avoiding using a CAD package. In order to achieve high accuracy of gear geometry CAD software has to be avoided as the loss of accuracy is a problem combined with using CAD software. In addition, Hertzian contact problem for spiral bevel gears is studied using traditional Hertzian contact theory. Further more, finite element model is also investigated to compare the stress to that achieved from Hertzian analysis. Finite element analysis is applied in order to determine the response of the structure and bending stresses. Finite element analysis code ABAQUS/Standard is employed.