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Need help finding a (low voltage) motor

Need help finding a (low voltage) motor

Need help finding a (low voltage) motor

(OP)
Hi,

I would like to have some help finding a suitable motor, used as an alternator/dynamo, that can generate around 6V and 600mA at low rpm (2000-2500 rpm).

I have been searching for a motor for days and I have trouble to find one. There are just too many types and sizes and my knowledge on motors is minimal.
I want to use the motor to charge a smartphone at 5V and 500mA.

Does anyone have a link or a good tip for me, so I can find the right motor?

Many many thanks in advance!

Maarten

RE: Need help finding a (low voltage) motor

A motor consumes electricity and does work, a GENERATOR takes work done by something else and makes electricity.

Maybe you meant to say you want to use a motor as a generator to generate at least 600ma at 6VDC from a prime mover that is spinning at 2000-2500RPM. In that case, all you really need is any small low voltage low power motor (probably Permanent Magnet DC), and a regulator board that will limit the voltage to a safe level for charging that cell phone. Do a search for "micro motors" and you can start with 6VDC, but that's actually kind of fast for a 6VDC motor that will produce 600ma, you may have to experiment with higher voltage motor designs that would run faster, then might give you what you need at a slower speed.
I would start at a surplus store like this, cheap experimental motors:
http://www.goldmine-elec.com/motors/

then you need to concern yourself with the details of how you plan to connect this shaft to your prime mover, how you plan to mount the motor and where you can safely house the regulator.

"Will work for (the memory of) salami"

RE: Need help finding a (low voltage) motor

(OP)
Hi jraef,

Thanks for your reply. That's what I meant by use a motor as a alternator/dynamo. Yeah, you can call it a generator too winky smile. I already ordered a low drop regulator and some capacitors to get a steady 5v output.

Ill have a look at your link. Thanks!

RE: Need help finding a (low voltage) motor

(OP)
Hi,

That looks good! Do you think the torque won't be too high? I tried another 3-phase and that one had too much torque...

RE: Need help finding a (low voltage) motor

Buy a toy motor designed to run on flashlight batteries. You may find one for under $5.00 at a hobby store. Radio Shack used to have suitable motors.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Need help finding a (low voltage) motor

amazon62 I am curious why you want a motor instead of $2 wall wart? perhaps no wall sockets where you want to use it? but what is there that rotates all the time for you to attach your generator to? how 'bout as Paul Harvey would say, the rest of the story? Sounds interesting....

RE: Need help finding a (low voltage) motor

(OP)
Hi Mike,

Sorry, I just wanted to have it short. But the story is:

I have 2 of those old FreePlay spring powered wind-up radio's (Freeplay FPR2 and 360), and I was wondering if I could make a phone charger with the same principle. So instead of all those direct hand-cranked chargers, one which you wind-up and let it to charge via the spring. The advantages of this method that you don't have to continuously have to crank with a certain speed, but just once with more power. And it is kinda nice to have an end to it and not have to crank until your arms fall off. 2nd benefit is not using batteries. But I already figured out that a really big spring is needed (lots of torque), which is size, weight and economic wise not really great. And off course it is not as efficient as batteries. But I want to check it out anyways... So now I'm doing tests with weights to see how much torque I need to spin the motor fast enough to power a smartphone. But the 3-phase motor I have now, is clogging too much and creates to much torque when on full load.

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