Recent Progress and Prospect on Tooth Modification of Involute Cylindrical Gear

Background: Recent reviews on tooth modification of involute cylindrical gear are presented. Gear pairs are widely employed in motion and power transmission systems. Manufacturing and assembling errors of gear parts, time-varying mesh stiffness, and transmission error of gear pair usually induce vibration, noise, non-uniformly load distribution, and stress concentration, resulting in earlier failure of gear. Tooth modification is regarded as one of the most popular ways to suppress vibration, reduce the noise level, and improve the load distribution of gear pairs. Objective: The objective of this study was to provide an overview of recent research and patents on tooth modification methods and technology. Methods: This article reviews related research and patents on tooth modification. The modification method, evaluation, optimization, and machining technology are introduced. Results: Three types of modifications are compared and analyzed, and influences of each on both static and dynamic performances of gear pair are concluded. By summarizing a number of patents and research about tooth modification of cylindrical gears, the current and future development of research and patent are also discussed. Conclusion: Tooth modification is classified into the tip or root relief along with tooth profile, lead crown modification along tooth width, and compound modification. Each could be applied in different ways. In view of design, optimization under the given working condition to obtain optimal modification parameters is more practical. Machining technology and device for modified gear is a key to get high-quality performance of the geared transmission. More patents on tooth modification should be invented in the future.