My thinking on gear ratios involving sun and ring gears is a little
but I think you are using a 1.5 to 1 ratio.
> The pitch is metric, module 1.0
Module 1 is .03937 inches pitch diameter per tooth.
> The sun gear has 30 teeth
That would be 1.1811 inches pitch diameter.
> The ring gear has 60 teeth
That would be 2.3622 inches pitch diameter.
> The planet gears have 15 teeth each
The planet gears would be .59055 pitch diameter.
> The gear width is 10mm or .3937"
Considering the limitations of size in a unicycle wheel hub width
I would consider going a little wider with the gears to gain strength
and longer life, if possible.
> The planets run directly on the shafts
I don’t know what you are using for shafts but what is known as
dowel pins are available fairly cheaply in lots of sizes. They
are smooth ground finished and hard. They are commonly
used to pin die parts together in punch press dies. Very tough
> > The gears are unhardened steel, oxide coated
The oxide coating is a start but small gears and other parts
can be sent to a heat treater and have a carbonizing process
that will harden them several thousanths of an inch thick.
That still leaves a non-brittle core of steel for shock strength.
Generally that does not warp them but leaves a surface coating
that needs to be smoothed with liquid hone. That is a stream
of oil with fine abrasive in it that shines the surface some. Lots
of heat treaters can do that for you too.
Just a few thougths I thought I’d pass along, my old company
does make gears of that size, but not the ring gear, and we often
had them hardened for wear. I am not trying to get any business
as I’ve been out of it for some time now.
> > Lowell Terry wrote:
> > > Harper, what is the pitch of your gears? How many teeth in the
> > > and how many teeth in the ring gear? How about the width of the
> > > Do you have needle bearings in the planetary gears or just a
> > > type bearing? What is the material of the gears and are they
> > > treated for hardness, wear?
> > –
> > harper
> > Posted via the Unicyclist Community - http://unicyclist.com/forums
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