Hello I am new to circuit building, but after playing the metro game series I decided i wanted to make a dynamo charger styled after the one in the games, but modified to fit with today's electronics, what i want is to build it so that at the flick of a switch or press of a button, that it will swap between powering a portable power bank for charging phones and the like, and supplying power to a battery charger to charge AA, AAA, potentially 18650, etc. batteries i have slightly created a circuit but i am now stuck and need some help, this is currently what i have, any feedback is greatly apprecited.

 

When you spin U1, how many volts does it produce?

 

currently unknown, i need to build the case and have the gears to get it to where it is capable of powering and charging through a usb cable as well as directly to the batteries themselves, right now i'm just trying to figure out the circuit so i know kind of what sort of space i need to account for when creating the case as i'd like to have it as low profile around everything as possible the main issue that i am currently unsure of is where ground and VCC should be placed in the circuit if that can be discerned now or whether i have to have other things in place first

 

The first thing you have to find out is the "oomph" it puts out.

 

On your USB you have your rectified DC connected to the data lines, any reason for that? Also you have your battery symbol backwards I think. With your AC source you will need to figure the forward voltage drop of your diode bridge and likely want a good 5 volt regulator in the mix.

Ron

 

The first thing you have to find out is the "oomph" it puts out.

ok so in relation to this by oomph i assume you mean voltage and amps out? and if so well i think we can get a guess on this based on the specs of the motor which is a motor out of a broken sewing machine which has written on it that with 220-240V 50Hz 0.3A 70W it will spin at 5500RPM i will upload an image in a moment of the label

 

 

You will never get it to spin that fast. You need a PM motor.

 

would it really need to spin at maximum rpm though?

 

You can't crank at much more than 100RPM and this needs a 50:1 gearbox and the friction will cost you a fortune. Buy an old ARMY gen-set and slash it to a tree and see how long you can crank it.

 

the way it is being built won't use a crank arm like on most common dynamo powered equipment, it will be trigger pumped similar to this https://en.wikipedia.org/wiki/Mechanically_powered_flashlight#/media/File:Knijpkat_996637.JPG but with a larger gear train and most likely a flywheel mechanism allowing for easier continuous pulls

 

You may want to consider that spinning an AC motor does not necessarily make it a generator. I doubt a sewing machine motor less a PM (permanent magnet) is going to self excite and generate anything. I would start by seeing if your motor will even function as a generator as step one.

Ron

 

i have checked it with a multimeter and spinning it by hand produces both voltage and amps, that was the very first thing i did after i pulled it from the sewing machine to ensure that it would work

 

i have checked it with a multimeter and spinning it by hand produces both voltage and amps, that was the very first thing i did after i pulled it from the sewing machine to ensure that it would work

Then see what you have? Spin the motor in the fashion you intend to and measure the voltage, then place a load on the motor and see how it does generating under a load.

Ron

 

being able to spin it in said fashion, fast enough to produce a decent voltage and ampere would require that i have a few gear and the trigger, which i currently do not have, due to current lack of funds, and only recently having actually obtained the sewing machine i took the motor itself from, from a family member who broke the machine