Accession Number : ADA257727


Title :   Application of Face-Gear Drives in Helicopter Transmissions


Descriptive Note : Technical memo.


Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER


Personal Author(s) : Litvin, F L ; Wang, J C ; Bossler, R B , Jr ; Chen, Y J ; Heath, G


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a257727.pdf


Report Date : Jan 1992


Pagination or Media Count : 10


Abstract : The use of face gears in helicopter transmissions was explored. A light-weight, split torque transmission design utilizing face gears was described. Face-gear design and geometry were investigated. Topics included tooth generation, limiting inner and outer radii, tooth contact analysis, contact ratio, gear eccentricity, and structural stiffness. Design charts were developed to determine minimum and maximum face-gear inner and outer radii. Analytical study of transmission error showed face-gear drives were relatively insensitive to gear misalignment, but tooth contact was affected by misalignment. A method of localizing bearing contact to compensate for misalignment was explored. The proper choice of shaft support stiffness enabled good load sharing in the split torque transmission design. Face-gear experimental studies were also included and the feasibility of face gears in high-speed, high-load applications such as helicopter transmissions was demonstrated.


Descriptors :   *HELICOPTERS , *GEARS , *TRANSMISSIONS(MECHANICAL) , VELOCITY , STIFFNESS , DRIVES , SELECTION , TORQUE , MISALIGNMENT , BEARINGS , ERRORS , ALIGNMENT


Subject Categories : Helicopters


Distribution Statement : APPROVED FOR PUBLIC RELEASE