Here's my take on it Kevin.
The main difference between manual & auto trans is the use of planetary
gears. This has pros & cons. Pros include higher HP rating per
pound (for planetaries) than other types due to the multiple tooth meshes
involved and no radial loads on sun and ring gears
& bearings. Cons include the fact that more gears & meshes
means more heat generated (no free lunch) so a cooler is needed.
That is really the only Con I can think of.
ATF has to be optimized for the torque converter and clutches used in auto
trans. We do not need those compromises so synthetic oil is a better
lubricant for our purposes.
A pressurized system is needed in my drive due to the plain bearings used
in some places (as Ken W. noted) and to spray the gears from the inside out to
insure the oil gets where it needs to be.
An separate oil pump and cooler would work fine and would allow an
even better choice of gear lube (George Graham is doing this) but it adds
complexity, weight and failure modes. Everything is a
compromise.
Once again, even though there are several thousand hours of total
test time on this design, it is still an experimental device and should be
recognized as such. There would have to be at least
10 units run through their expected TBO before they could be considered a
thoroughly tested design. This is the nature of Experimental
aviation.
Tracy Crook, RWS
----- Original Message -----
Sent: Wednesday, December 06, 2006 12:39
AM
Subject: [FlyRotary] redrive lube
i am asking this question with only the
experience back in college years of putting a buick v-6 in a 1953 willys, no
race car experience etc......
auto transmissions have special fluid and
coolers because of the torque converters, right? manual transmissions
just have gear lube, which, it seems, you put in and basically forget
about. what is different about the PSRU redrive from a manual
transmission? why can't it be self-contained with gear lube and
forgotten? are planetary gears
different from a manual transmission? are they fed with an oil flow and
coolers in trucks? i'm sure all of this has already been answered and
thought out. ken said he keeps his redrive lube separate from the
dirty engine oil. why are tracy's redrives plumbed as part of the engine
oil flow? kevin (just
curious)