RDS-21 Face-Gear Surface Durability Tests

Experimental fatigue tests were performed to determine the surface durability life of a face gear in mesh with a tapered spur involute pinion. Twenty-four sets of gears were tested at three load levels: 7200, 8185, and 9075 lb-in face gear torque, and 2190 to 3280 rpm face gear speed. The gears were carburized and ground, shot-peened and vibro-honed, and made from VIM-VAR Pyrowear 53 steel per AMS 6308. The tests produced 17 gear tooth spalling failures and 7 suspensions. For all the failed sets, spalling occurred on at least one tooth of all the pinions. In some cases, the spalling initiated a crack in the pinion teeth which progressed to tooth fracture. Also, spalling occurred on some face gear teeth. The AGMA endurance allowable stress for a tapered spur involute pinion in mesh with a face gear was determined to be 275 ksi for the material tested. For the application of a tapered spur involute pinion in mesh with a face gear, proper face gear shim controlled the desired gear tooth contact pattern while proper pinion shim was an effective way of adjusting backlash without severely affecting the contact pattern.

[1]  Faydor L. Litvin,et al.  Design and Geometry of Face-Gear Drives , 1992 .

[2]  Jie Tan Face Gearing With a Conical Involute Pinion: Part 1 — The Conical Involute Gear: Definition, Geometry and Generation , 2002 .

[3]  Ichiro Moriwaki,et al.  Stress Analysis of Face Gear Tooth Subject to Distributed Load Using Global Local Finite Element Method (GLFEM) , 2003 .

[4]  Sandro Barone,et al.  Evaluation of the effect of misalignment and profile modification in face gear drive by a finite element meshing simulation , 2004 .

[5]  Robert F. Handschuh,et al.  Experimental Testing of Prototype Face Gears for Helicopter Transmissions , 1994 .

[6]  Jie Tan Face Gearing With a Conical Involute Pinion: Part 2 — The Face Gear: Meshing With the Pinion, Tooth Geometry and Generation , 2003 .

[7]  Neil Anderson,et al.  8th International Power Transmission and Gearing Conference , 2000 .

[8]  David G. Lewicki,et al.  Torque Splitting by a Concentric Face Gear Transmission , 2002 .

[9]  Hon Wai Chun,et al.  Analytical determination of load distribution in a statically indeterminate face gear transmission , 2006 .

[10]  Michele Guingand,et al.  Analysis and Optimization of the Loaded Meshing of a Face Gear , 2003 .

[11]  Robert C. Bill Advanced Rotorcraft Transmission Program , 1990 .

[12]  Robert F. Handschuh,et al.  Evaluation of Carburized and Ground Face Gears , 2000 .

[13]  Faydor L. Litvin,et al.  Handbook on Face Gear Drives With a Spur Involute Pinion , 2000 .

[14]  Claudio Zanzi,et al.  Application of modified geometry of face gear drive , 2005 .

[15]  Faydor L. Litvin,et al.  Application of Face-Gear Drives in Helicopter Transmissions , 1994 .

[16]  Donald R. Houser,et al.  Face Gear Transmission Development Program at Sikorsky Aircraft , 2003 .

[17]  David G. Lewicki,et al.  Experimental Evaluation of Face Gears for Aerospace Drive System Applications. , 1996 .

[18]  Michèle Guingand,et al.  Quasi-static analysis of a face gear under torque , 2005 .

[19]  Gregory F. Heath,et al.  Development of Face Gear Technology for Industrial and Aerospace Power Transmission , 2002 .

[20]  Sigmund J. Amster,et al.  The Statistical Treatment of Fatigue Experiments , 1964 .

[21]  R Robert,et al.  Face Gear Finite Element Stress AnalysisTool Development , 2004 .

[22]  M. Guingand,et al.  Analysis and Optimization of the Loaded Meshing of Face Gears , 2005 .