Accession Number : ADA289966

Title :   Generation of Gear Tooth Surfaces by Application of CNC Machines.

Descriptive Note : Final contractor rept.,

Corporate Author : ILLINOIS UNIV AT CHICAGO CIRCLE

Personal Author(s) : Litvin, F. L. ; Chen, N. X.

PDF Url : ADA289966

Report Date : APR 1994

Pagination or Media Count : 84

Abstract : This study will demonstrate the importance of application of CNC machines in generation of gear tooth surfaces with new topology. This topology decreases gear vibration and will extend the gear capacity and service life. A preliminary investigation by a tooth contact analysis(TCA) program has shown that gear tooth surfaces in line contact (for instance, involute helical gears with parallel axes, worm-gear drives with cylindrical worms etc.) are very sensitive to angular errors of misalignment that cause edge contact and an unfavorable shape of transmission errors and vibration. The new topology of gear tooth surfaces is based on the localization of bearing contact, and the synthesis of a predesigned parabolic function of transmission errors that is able to absorb a piecewise linear function of transmission errors caused by gear misalignment The report will describe the following topics: (1) Description of kinematics of CNC machines with 6 degrees-of-freedom that can be applied for generation of gear tooth surfaces with new topology. (2) A new method for grinding of gear tooth surfaces by a cone surface or surface of revolution based on application of CNC machines. This method provides an optimal approximation of the ground surface to the given one. This method is especially beneficial when undeveloped ruled surfaces are to be ground. (3) Execution of motions of the CNC machine. The solution to this problem can be applied as well for the transfer of machine-tool settings from a conventional generator to the CNC machine. The developed theory required the derivation of a modified equation of meshing based on application of the concept of space curves, space curves represented on surfaces, geodesic curvature, surface torsion, etc. Condensed information on topics of differential geometry is provided as well. (MM)

Descriptors :   *GEAR TEETH, VIBRATION, MANUFACTURING, LIFE EXPECTANCY(SERVICE LIFE), ERRORS, DESIGN CRITERIA, MISALIGNMENT, GEARS, GRINDING, WORM GEARS, METAL CONTACTS.

Subject Categories : Machinery and Tools

Distribution Statement : APPROVED FOR PUBLIC RELEASE