I am working on a project where we are trying to create a hand powered portable charger. I want to run a small motor as a generator and am wondering if anyone knew any specific motors that might do the job. The mechanism is going to rack and pinion system to drive the motor shaft via some gear mechanism. I had this motor in mind: # ROB-20441. I just don’t see how I can run it in reverse since it has no shaft. Please let me know if I’m confused or if there are other possible products that can do the job.
Thanks
eh…making a 3-phase hand-crank portable charger is probably a large undertaking
You could probably combine a small hand crank with this motor and a stepdown converter (set to 4.2v output, presumably) to charge a standard 1s something (3.7v nominal for a lipo battery)
If you are wanting to charge a 5v device (usb, etc), grab SparkFun BabyBuck Regulator Breakout - 5V (AP63357) - COM-21256 - SparkFun Electronics as the stepdown and a wire whichever cable needed to its output
This motor would output an AC current correct, so I’ll probably need a rectifier to convert the AC to DC current. What is the phase of this motor you recommended? I am also not charging a phone directly, I am charging a battery which would then charge a device like a phone. You did say charge a standard 3.7v battery, which I think we were planning on using. We might hook 2 batteries in series but I didn’t do the calculations on so I’m not sure how it works. Please give me some advice.
To do real work with human power (vs a brief visual aid, a demonstration) like battery charging, stick with a ready made generator. You’ll appreciate the efficiency gains, determined by the (perspiration*Watts)^goddammics calculus.
I always thought these were pretty cool:
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Any brushed DC motor will act as a generator of DC current. Polarity of DC output depends on the direction of shaft rotation.
Brushless motors (without driver electronics) used as a generator will produce AC voltage, which must be rectified in order to make a charger.