Wind-up Torch Hand Cranked, Dynamo, LED -Amended-





Introduction: Wind-up Torch Hand Cranked, Dynamo, LED -Amended-

Parts list

A white 5mm LED. I think it's 2000mcd, it came out of my junk box.
A red 3mm LED - high brightness. Optional. Lights when the capacitor is being charged by the dynamo.
A 1 Farad, 5.5 Volt capacitor.
A hand held crank dynamo. I got it at Jaycar electronics. I think the motor/gearbox from a simple toy car would probably work just as well.
It puts out about 5 Volts at top speed, so I thought it was a good idea to use a comparable capacitor.

Lots of patience. And coffee. And ciggies.

The switch stops the capacitor from discharging straight into the white LED, that would make it a hand-cranked light, and not a wind up, to use hands free, torch.

Step 1: The Dynamo Crank

This is the dynamo crank. Turn the handle on the side and the gears turn the dynamo, and through the magic of science, electricity comes out...

Step 2: The Little Red LED

This is the little red LED not lighting because it's really hard to crank the dynamo and take photos at the same time.

Step 3: The Little Red LED Who Could...

This is the little red LED being a team player, and lighting, to show I'm cranking the dynamo...

Step 4: Let There Be Light!

I plug the red wire into the negative terminal strip (because I'm too cheap to use a switch in something I'm only breadboarding), and Presto! Light!
Not bad for a cheap white LED, around 2000mcd I think.

Step 5: The Schematic

The amended schematic, showing the (optional) red LED facing the right way.
Sorry about the mistake, my bad.

Step 6: The Dynamo Crank Unit

Three photos that may make it a bit clearer as to how it works.
First, the unit side on.

Step 7: The Dynamo Crank Unit, Side On

Conventionally, power is applied to a motor, through the solder tabs, turning the motor and the drive shaft.
The dynamo crank works in reverse, turning the drive shaft and the motor, and supplying power through the solder tabs, to the circuit.

Step 8: The Dynamo Unit Face Up

Turning a motor spindle by hand, to generate power, is not as efficient as using a gearbox, unless you have plenty of time...

Step 9: The Gearbox End-on.

A blurry photo showing the gearbox end on.
As you might be able to see, the gearbox is used to turn the drive shaft of the motor.

Step 10: Probably Not the Last Step...

I've had to amend the schematic because I'd put the red LED in the wrong way around.
Thanks to LasVegas for pointing that out.



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    Great eco design! My only question is, Where did you get the gear settup and crank from? Did you make that yourself or did you just steal one from something else?

    Great eco design! My only question is, Where did you get the gear settup and crank from? Did you make that yourself or did you just steal one from something else?

    will a normal toy motor really work??? im not sure.....
    plz comment/reply

    Your small LED is backward in the schematic.

    The small LED has to be backwards. It's to stop the capacitor discharging back into the motor. It looks wrong, I know, but it does work.

    That's what I mean. It has to have the cathode (flat side) on the positive side of the capacitor to allow charging of the capacitor and prevent discharge through the generator. If you follow the path of discharge with the switch off, you'll see that the schematic has both LEDs with the same polarity.

    You built the circuit right. You just made a minor error on the schematic. The attached (corrected) schematic shows the charging path of current (blue) and the discharge path (red). As you can see, as in any diodes, current flows into the LED's cathode against the arrow. This is a carry-over of the pre-transistor belief that current flowed from positive to negitive.

    Picture 3.png

    thanks and please launch the right schematic or instructables

    Thanks. I stand corrected. I'm not too bad with a soldering iron, but my theory work is terrible. Appreciate the input.

    Where can you get these capacitors!!! I can't find many suppliers in the UK, so if anyboady knows of any cos i really gotta get my hands on some (Or if anyone knows what electric appliances have these caps in). Or i think some USA company could ship one to me.....