One of the current research
activities here at California State University at Fullerton is systematization of existing knowledge of design of planetary gear trains.
Much of the information in this article
has been extracted from an AGMA
Technical Paper, "What Single Flank
Testing Can Do For You", presented in
1984 by the author
Material losses and long production times are two areas of conventional spur and helical gear manufacturing in which improvements can be made. Metalforming processes have been considered for manufacturing spur and helical gears, but these are costly due to the development times necessary for each new part design. Through a project funded by the U.S. Army Tank - Automotive Command, Battelle's Columbus
Division has developed a technique for designing spur and helical gear forging and extrusion dies using computer aided
techniques.
With the publishing of various ISO draft standards relating to gear rating procedures, there has been much discussion in technical papers concerning the various load modification factors. One of the most basic of parameters affecting the
rating of gears, namely the endurance limit for either contact or bending stress, has not, however, attracted a great deal of attention.
History comes around full circle. It is interesting to talk to gear manufacturers who service the defense, aerospace, automotive and computer industries and find that their sales, production and backlogs reflect excellent and, in some cases, record breaking business.