Paul,
I think I see where you are going.
If you use a hollow pipe and press the ball bearings sets into each side,
then you can make those rollers very light and control strength by varying
the wall thickness .and retain a balanced mass. Drilling holes would mean
most likely each roller would need to be mass balanced afterwards.
A through shaft can be secured by a bolt or spring clip on one end.
I like the carrier on this. One piece aluminum?
A couple points to consider,
In the standard design:
At speed, the centrifugal forces (not CGs my mistake) are being contained in
by the case and the power comes off of the ring. We are in agreement that
the rollers bearings take the predominate forces since they are locked into
the case. They are also loose though. The ring in this case experiences a
the centrifugal forces as well as a deflection force as it passes over the
bumps in the road. These bumps are the outer edge of the roller each time it
passes.
With the power taking off of the planet carrier we have a greater mass now
spinning. The bumps in the road are greater because the three rollers are
trying to head out through the case, there weight and balance combined with
the planet carrier. I think in this case we would want the bearings to be
tight, to limit the outwards travel.
Trying to make the case the same as the ring seems time saving but the end
plates would be where the stress will happen. We still need to get at least
two bearings on the shaft to the right of the oil pump and a robust cover to
support the output shaft.
I believe that is why ROTREX mentioned securing the outer ring within
another aluminum case with some sort of flexible retainer spring.
They are working on this carrier design for a wind generator as we speak.
Soon soon
Doug
-------------------------------------
The carrier is steel to control expansion rates.
The end plates will be loose to allow the ring to flex a few thou.
The FEA proved the flex is not much. With 2000 pounds of normal
force the deflection was minimal. See the new 3D. No holes
in the outer ring as they would cause stress concentrations.
Remember this is four inches OD so the carrier is on the order
of only three inches OD revolving at only `12,000. There are some
Mazda 13B's around revolving at 12,000 RPM.
Good idea on balancing the rollers. They are zinging along at 26,000 RPM.
BTW nothing wrong with those Torrington precision caged roller bearings.
26,000 RPM no problem. They will easily accomadate the aprox 1500 pounds
radial force due to their own mass and that of the roller.
This thing is a peice of cake. We grind several small shafts and
vary the OD by .001. Same for the ID on the ring. Vary the ID by
.001. That way we can try different pre loads with the same rollers
and planet carrier.
Bumps? What are Bumps? Every thing is ground to .0001. One tenth
of a thou.
Paul Lamar ...No rotor no motor.
Paul
OK sounds good. Probably best to balance the carrier unit as a set as well.
What is your carrier holder material made from?
Bumps were my feeble analogy of what the any cross section of the ring sees
each time the roller goes by. In other words the ring flexes 36,000 times
per min.
Doug in Japan
----------------------------------------------------
I don't think so, Unless of course the rollers are out of round.
the ring flexes the same number of times as the planet carrier goes around
which is 12,000 times minute IMHO. It is going to make some interesting noise
:)
I think the output shaft and the planet carrier can be made from one
piece of 4340 steel. This is a small part after all. 3" OD with a
.625 output shaft.
Paul Lamar ...No rotor no motor.
Paul
Do you think we need two gear pumps? With the reservoir and cooler below the
unit, gravity drain should be adequate. It works for turbochargers.
Doug in Japan.
I don't know yet but just in case I am not taking any chances :)
Did you notice any break-away torque on the Rotrex unit?
Paul Lamar ...No rotor no motor.
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