# Magnomatics Pseudo Direct Drive motor



## AmpEater (Mar 10, 2008)

Wow, very cool. Still wrapping my head around this technology


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## major (Apr 4, 2008)

AmpEater said:


> Wow, very cool. Still wrapping my head around this technology


Hi Amp,

Thanks for posting. Being Franky's first post, I thought it might be spam, so didn't click on it until I saw your post.

Fascinating concept. You'd think those iron bars would really heat up with all the magnetic reversals and not being shown as laminated. So I have my doubts as to the viability, especially with the cost of magnets. But still very interesting.

major


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## Salty9 (Jul 13, 2009)

The bearings would be very interesting if they matched the narrator's description of no wear and needing no lube.


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## gmijackso (Sep 30, 2008)

Seems somewhat similar to the "Magnadrive", in basic concept at least. http://www.magnadrive.com/ I don't however see the benefit of using the magnomatics device.


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## major (Apr 4, 2008)

gmijackso said:


> I don't however see the benefit of using the magnomatics device.


Hi gmij,

I am wondering the same thing. Net searches don't turn up anything of substance regarding it. I did find this diagram.

major


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## AmpEater (Mar 10, 2008)

gmijackso said:


> I don't however see the benefit of using the magnomatics device.


Wouldn't the benefit be the same as the benefit of gear reduction? Minus meshing surfaces, which is the downside with gear sets?

I'm having a harder time not seeing the potential benefits of a non-contact coupling device with integral reduction as an option. The inherent "slip-clutch" effect would be usefull to isolate motors from stall and overload conditions. As a hub motor reduction it may be usefull to prevent a locked/shorted rotor from locking up the associated wheel.



Whether it's cost effective, suitable for a particular application, or lives up to efficiency and performance claims is another matter all together. 

As far as a direct drive hub motor goes it does seem like you'd be better off using those magnets and copper to just build a bigger direct drive brushless motor with an increased number of poles, weight/performance wise


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## major (Apr 4, 2008)

AmpEater said:


> Wouldn't the benefit be the same as the benefit of gear reduction?


Except I fail to see the mechanism by which torque can increase from input to output shaft.


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## AmpEater (Mar 10, 2008)

major said:


> Except I fail to see the mechanism by which torque can increase from input to output shaft.


Well it stands to reason that a decrease in rpm can be translated into an increase in torque....but I don't really "get" how that is, or could be achieved, either. 

The other site, http://www.magnadrive.com/, doesn't claim any gear reduction capabilities as far as I can see, only the ability to run a load at a lesser speed than the motor. hmm


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## major (Apr 4, 2008)

AmpEater said:


> Well it stands to reason that a decrease in rpm can be translated into an increase in torque......The other site, http://www.magnadrive.com/, doesn't claim any gear reduction capabilities as far as I can see, only the ability to run a load at a lesser speed than the motor. hmm


Hi Amp,

Yeah, that is a clutch. And like a friction clutch, can have difference in speed between input and output, but at basically the same torque. Whereas gear systems derive the increase in torque from different pitch diameters (lever arms) and have a torque ratio basically equal to the inverse of the speed ratio. 

Regards,

major


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