Dishwasher Motors For Ebikes?

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Dishwasher Motors For Ebikes?

First thing is to identify what the motor actually is. It has two wires and a ground wire. The coils are two in number and they wrap around an iron laminated core. I'm unable to see inside to look at the rotor, but my guess is that the rotor is a permanent magnet.

Using RC motor terminology my guess is that this is a brushless "outrunner" motor. The size is about right for ebikes as can be seen in the photo.

Now one can ask:

"Why not just buy a high quality brushless RC motor and start there?"

...and my answer would be:

"Yeah, that's probably true..."

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I think it's interesting that these exist and can be gotten for free because of the large number of dishwashers in the world. Efficiency is likely not very good though, since it's running off of the grid.

Why just two coils?

Since it's designed to move water (which is heavy) you would think that it would need to have some pretty good low end torque.

I wonder if something so simple and minimal could be used?

(no brushes to wear out)
 

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I have to rub the ol' forehead for a few moments on this one. Great theory. Ive only begun my journey of electric motors a few months back.
I hope someone knowledgeable chimes in. You may have just scratched the surface within the appliance world. :geek:
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It is most likely a universal motor. It would run on AC or DC. It would have brushes, and probably two field coils. The two power wires are hot and neutral, and then the third is a case ground.


It would need a good rewind, for it is designed for 120v AC (rms) use. Starting torque is great on universal motor, but efficiency isn't great.
 
My question is this: Given that the primary limiter of the utility of e-bikes is the power storage issue, why would you use a motor that is not as efficient as you can get?
 
My question is this: Given that the primary limiter of the utility of e-bikes is the power storage issue, why would you use a motor that is not as efficient as you can get?

Simon presents a seriously valid point here. The wieghs out justify the means.

A good idea would be to use that motor on a windmill! Never thought of a DW motor. Low RPM would probably work well to generate 110. I wouldn't know the first thing about regulating it tho.
 
If looking for a cheap motor to adapt to a bike, the old car fan radiator motors were an early concept. Not that efficient, but the price is good. A few companies made these types years ago, but I don't know of anyone now. They were $$$$ when new. Look up; EV Warrior bike

http://www.psnw.com/~jmrudholm/ebike.html
 
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It is most likely a universal motor. It would run on AC or DC. It would have brushes, and probably two field coils. The two power wires are hot and neutral, and then the third is a case ground.

There is no brush drag at all... it's completely free spinning... so it does appear to be a brushless motor.

I tried connecting it to a 12V battery and it behaves like a brushless motor in that flicking the wires to the terminals can actually get the motor to move a little. (sort of like hand timing of the current pulses)

Efficiency has two parts... there is "peak" (at a specific rpm) and "average" (across the entire powerband). It's hard to know what the efficiency might be just by guessing.

Not all motors are alike... and my guess is that for something like a dishwasher the goal is to be able to get good low end torque and so while high rpm efficiency might not be ideal the overall power and efficiency might not be bad. I'm thinking it might be more like an induction motor or something. (I have no idea what the rotor is like)

It's interesting no matter what... :unsure:
 
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There is no brush drag at all... it's completely free spinning... so it does appear to be a brushless motor.

Most likely just an AC induction motor. A brushless DC motor would have at least three wires along with the frame connection, and a fairly sophisticated motor controller.

I've seen some Electrolux/Frigidaire dishwashers that used permanent magnet DC motors for their pumps. Looked like a power wheels motor with a rectifier bridge built-in to convert the AC to DC. Thought it looked a bit cheap at first, but they run very quiet without the typical induction motor hum. You can hear a little bit of a whine from the brushes, but it was barely noticeable.
 
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