CAD and Optimization of Spur and Helical Gear Sets
Abstract The present work is an application of Computer Aided Design and optimization techniques to solve the problem of designing a pair of gears. The CAD programs have the initial freedom to change the design variables: the module, the number of teeth, the face width, and the material through a data base display, and a full detailed design stage that applies the AGMA bending and contact number checking criteria, and the bending fatigue strength and the surface endurance strength criteria. Other programs are also linked to optimize spur gears under the objective of minimizing the volume. The design vector is taken to be the module, the number of teeth, and the face width, with the interaction between bending and contact stress constraints. These programs were utilized to study the behavior of the optimum parameters for a full range of cases. Charts of the optimum results are plotted. For optimizing helical gears, the design vector is taken as the module, the number of teeth, the face width, and the helix angle. A comparison is made between values of the objective function and optimum parameters for spur and helical gears for a wide range of cases. A comparison is also made of the results with other previous works of optimization and proved that the approach presented here gives better optimum results for the same loading case.