Quote:
Originally posted by M. Krass
How could this work without the one way clutch? If there's no clutch to slip when the output spins faster than what the high-torque motor is capable of at free-speed, that motor will drag and be spinning faster than it's free-speed.
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I think he's talking about using a reversible clutch bearings, like the one's used in socket wrentches. There's no way this idea could be implemented without the use of a clutch bearing.
I've thought about using such a design before, but ruled it out because reversible clutch bearings are rather complex.
As for spinning a motor faster than it's free speed, Lenz's law prohibits this. If a motor is electrically connected, it will act as a generator, creating a resistive force to the object that is turning it.
Although, the speed controllers do technically have the ability to disconnect a motor electrically. You could implement the idea without a clutch bearing as long as the 2nd motor is off when you try to use the high-speed motor. The negative side of this is that you'd be adding to the overally inefficiency of the drive system because you're rotating more mass inside the motor. Also, the brushes and bearings add inefficiencies. Overall, your efficiency would probabaly drop by 20%. I'd only do this if the high speed motor is 2x the low speed motor, because of the inefficiencies.