Accession Number : ADA295425

Title :   A New Approach for Optimum Gear Design. Strengthening Spur Gears by Altering Stress Distribution.

Descriptive Note : Final rept. 27 Sep 93-28 Feb 95,

Corporate Author : CENTRAL STATE UNIV WILBERFORCE OH DEPT OF MANUFACTURING ENGINEERING

Personal Author(s) : Grissom, William A. ; Brown, Max L. ; Masoud, Samer ; Sutliff, Jeff

PDF Url : ADA295425

Report Date : 28 APR 1995

Pagination or Media Count : 8

Abstract : A new approach was investigated for achieving lighter spur gears with longer service life by altering the stress distribution in the gear by introducing hollow and filled holes through the gear face parallel to the shaft axis. The study was conducted using two-dimensional I-DEAS and ANSYS finite element models. The intent was to strategically redistribute the stresses to reduce the critical stress at the root fillet of the tooth. Stresses at the contact area were also monitored. Three strategies were investigated: (1) various hollow hole patterns; (2) press/shrink-fit plugs in the holes to introduce a compressive preload; (3) a high modulus of elasticity insert in a gear blank of low modulus material. The hollow hole patterns reduced the fillet stress up to 5% while increasing contact stress and deflection slightly. Press/shrink-fit plugs which imparted an initial compressive stress at the fillet reduced the stress only slightly more than holes alone. High modulus inserts in a low modulus gear gave the best results, achieving up to 50% stress reduction at the fillet while also reducing the contact stress and tooth deflection.

Descriptors :   *GEARS, STRESSES, MATHEMATICAL MODELS, ANGLES, OPTIMIZATION, STRATEGY, LIFE EXPECTANCY(SERVICE LIFE), FATIGUE LIFE, TWO DIMENSIONAL, FINITE ELEMENT ANALYSIS, DEFLECTION, HOLES(OPENINGS), LONG LIFE, SHAFTS(MACHINE ELEMENTS), FILLING, COMPRESSIVE PROPERTIES, BENDING STRESS, GEAR TEETH, STRESS CONCENTRATION.

Subject Categories : Machinery and Tools

Distribution Statement : APPROVED FOR PUBLIC RELEASE