25 Sep
2009
25 Sep
'09
3:15 a.m.
On 24 Sep 2009 at 23:55, Brent Hilpert wrote:
FWIW, this shows up with a search for "pulley
crowning":
http://www.lhup.edu/~dsimanek/scenario/crowning.htm
(click thru to the answer page). It looks familiar, I think somebody
else pointed to the same page during a previous discussion of this
topic on the list.
Probably a couple of years ago when discussing turning a new pulley
for a 50Hz-to60Hz floppy conversion. (On my floppy conversion, I
used a flanged pulley, which worked just fine).
I've seen lots of explanations of the crowned pulley, but none makes
me feel really good about it. Apparently a stiff flat belt with no
elasticity will not work. I've seen statements to the effect that
the crown has to be a smooth radius, but I've also seen plain old
"tracking sleeves" attached to flat pulleys for the same purpose.
I wonder if crowning works because the force on a flat belt is the
least at the top of the crown than on the smaller sides.
I dunno.
--Chuck