Description
New Age International (P) Ltd., Publishers Gears : Rigorous Demands Of Aviation, Marine, Power And Automotive Applications by A S Rangwala
This book is intended to understand and evaluate the dynamics of obtaining the profile of gear teeth, fabrication and operation of smoothly rolling meshing gears. Gearing has the potential to be a very complex subject, especially when dealing with multidimensional curved surfaces of the coupled teeth. For maximum rolling efficiency, formed teeth turn out to be far more successful in the task. The teeth profiles are described by mathematical or geometric laws of involute curves. Used in the design of spiral, hypoid and spiroid gears, the involute form is the favorite tooth profile, satisfying the need for high efficiency while permitting ease of manufacture.
Many different sources of gear teeth failure exist, ranging from excessive wear to catastrophic breakage. A surface phenomenon, wear results in removal of layers of metal from the contacting surfaces of the gear teeth. Design errors are sometimes responsible for overloaded teeth and tooth tip interference. Gears may experience premature failure due to surface-contact fatigue, arising from inadequate surface smoothness of the gear tooth face. Lubrication deficiencies occur at the contacting surfaces of the gears due to inadequate characteristics and overheating of the oil film, subsequently leading to direct metal to metal contact. Direct contact produces alternate welding and tearing, and rapidly removes metal from the contacting surfaces. Pitting, a surface fatigue failure, and fracture failure are the consequences.
The author has focused attention on new design features and operating requirements of the machines. A number of practical example problems illustrate the application of theory.