simple generator?

[opticsman]

Hi all , I read a thread about this which mentioned generators for LED flashers in shoes and yoyos etc. Can someone kindly explain how these work and the key parameters . For example what determines the power or voltage available from such a device? I guess flashing lights on bycicles use virtally the same principle? are energy storing devices ( such as capicitors ) used in such arrangements so that the LED can be lit when the motion stops? I am trying to see if i can use this principle to Light up some high power LEDs . Not my field so any advice will be appreciated. Thanks . Opticsman.

 

[itsmoked]

Most actually have batteries and a switch which responds to the motion.

In the few cases where there actually is a generator they work just like the 'shaker' flashlights.

Google for "shake flashlight" find a clear,(see thru) one, buy it, and learn.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[OperaHouse]

LEDs typically require a little more voltage than the standard 1.5V battery. In cases that use only a 1/5V battery, a capacitor is charged and then placed in series with the 1.5V battery to provide enough voltage. Over the years many methods have been used when battery voltage is 1.5V to flash a LED.

 

[VEBill]

"...LED flashers in shoes and yoyos etc."

I've taken apart several examples of each. The running shoes typically use a 3-volt CR20xx-series cell. The yoyos typically use several small alkaline button cells in series.

The only thing I've seen like a shake-powered flashlight are the shake-powered flashlights.

 

[MacGyverS2000]

If by "high-power" you mean those 1W+ LEDs, you're not going to find a small generator that will be able to power those from simple motion like walking... on a bike wheel, shouldn't be a problem. As Keith mentioned, though, the items you specifically mentioned do not run off of generators, they use batteries and motion-activated switches due to the low power-generating capabilities of generators of that size I mentioned previously.

Dan - Owner

http://www.Hi-TecDesigns.com