Investigation of spiroid gear tooth tangency under action of errors

The paper presents results of the analysis of manufacture and assembly errors' effect upon position and size of contact pattern in a cylindrical-worm spiroid gear also known as Helicon gear. Both independent and combined effects of the errors are studied. Alternative techniques of contact pattern quality improvement are discussed. One of them is based on the use of adjusting elements embedded in gearbox design. Another common technique suggests meshing elements' flanks' modification - crowning - that provides contact pattern localization ensuring reduced sensitivity of the gear with respect to said errors. The paper describes kinds and techniques of this sort of modification.