light twins?

Rusty,

I don't want to beat this issue to death, and I'm not a power transmission
expert either, but this is the first time I've heard of "amplitude" as an
issue in redrive design.

Usually the redrive designer is concerned with handling the maximum torque
and will devise a load model that will encompass the worst-case operating
scenarios.

I think the guy is referring to amplitude of power pulses because the torque
coming from an internal combustion engine is not linear like in an electric
motor, or turbine -- it has torsional spikes.

Still, compared to a piston engine, the rotary is a pussy cat when it comes
to torsional issues, because it does not have the lever-arm effect of the
crankshaft throws to worry about -- which creates the bulk of the torsional
flex in a piston engine.

When it comes to belt drives, the manufacturers have two ways of rating
them: one for smooth, continuous power like electric motors, and another for
combustion engines.

They also rate them for max continuous torque, so I feel pretty safe in
saying that with a single rotor engine making half the torque, you will need
less belt. With a gearbox, the dynamic gear tooth leads will likewise be
less.

Regards,

Gordon.




"Gordon Arnaut" wrote in message
...
Rusty,

Yes, I meant exactly what you said: three power pulses per single rev of
the rotor, and one pulse per rev of the e-shaft.

Regards,

Gordon.

PS: I like that you are using a turbo as a muffler -- not much more
weight, similar or even better noise reduction, not to mention the power.




"Russell Duffy" wrote in message
...
As far as I can see, this cannot be valid. If I'm thinking this through
correctly, each rotor will make three power pulses for each revolution
of
the rotor, or one revolution of the e-shaft.

My recollection from my mechanicking days is that the eccentric shaft
rotates at three times the speed of the rotor.

Abolutely right Corky. Gordon got it right in the rest of his post, so I
just figured he left out a word above, and it should have read "one PER
revolution of the e-shaft".

Cheers,
Rusty