Over the past few months we've talked with a lot of gear manufacturers. Many of them tell us business is strong, while others are struggling with reduced demand. The difference between them isn't so much in the quality of their manufacturing operations, but rather trends in the end markets they serve.
In the August 2008 issue of Gear Technology, we ran a story (“Gearbox
Speed Reducer Helps Fan Technology for ‘Greener” Jet Fuel Efficiency’) on the
then ongoing, extremely challenging and protracted development of Pratt
& Whitney’s geared turbofan (GTF) jet engine.
Gears with an asymmetric involute gear tooth form were analyzed to determine their bending and contact stresses
relative to symmetric involute gear tooth designs, which are representative of helicopter main-drive gears.
Getting rid of personal mementos is an arduous housekeeping ritual for some
of us; every last gear has a memory. One man’s trash is another man’s gold, after all, or in some cases, one failed business is a forgotten piece of personal and mechanical genealogy. Such is the case of the Hill-Climber chainless bicycle, the remains of which were pulled from a family junk pile after nearly half a century.