Shakeable Flashlights

[smearbrick1]

Has everyone seen those flashlights that you shake and it produces light? Apparently the shaking action creates electricity which is then stored in an electrical capacitor or something and is then passed to a small but very bright LED. At least this is my understanding.

Anyone know how much voltage is produced by the flashlight? How about amperage? I realize the amount is small, but if you could use a large capacitor or multiple flashlight generators... maybe you could make something that would power a cd player, or keep your Ipod charged just by motion.

[ps2daddy]

Passing a magnet through an electric coil produces electricity and a capacitor can store the energy produced and can be use for the led in a flash light (also if you run electric current through a coiled wire you can also creat an electromagnet)

I think they are working on shoes or belt that could do just that for an ipod they already have a solar battery attachment

They also are working on a windup laptop that is supposed to be a little as $100 for 3rd world countries (we'll see if they ever let that happen)

[smearbrick1]

Passing a magnet through an electric coil produces electricity and a capacitor can store the energy produced (also if you run electric current through a wire you can also creat an electromagnet)

I think they are working on shoes or belt that could do just that for an ipod they already have a solar battery attachment

They also are working on a windup laptop that is supposed to be a little as $100 for 3rd world countries (we'll see if they ever let that happen)

I understand how it works... I'm pretty sure I described how it works. I was merely wondering how much juice it produced. I imagine with the right capacitor and a decent sized coil/magnet combination, you could probably create a pretty good jolt of electricity.

That gives me a good idea for a personal protection device. Imagine a device you could keep on your keychain that worked like a stun gun that never needed batteries.

I saw the windup laptop. I too have my doubts as to whether anyone will let that MIT group sell them for $100.00. I guess it is to be Linux based. I've seen a prototype of one, very cool.

[Conquest10]

Its alright.

How do you resize an image in bbcode?

[MackemX]

I've got my own torch to shake

[Grimey]

I've got my own torch to shake

well, that didn't take long


:P

[Doramius]

It sounds like you're talking about the HUMMER flashlight.

http://www.i4u.com/article516.html

All the rugged Hummer® flashlight ever needs is a quick 30-second shaking to generate power for up to five full minutes of bright illumination. Inspired and licensed by GM's intrepid Hummer, this shockproof, rubber-guarded, waterproof and floatable flashlight is ideal for outdoor use and perfect for every vehicle or home emergency kit. Its LED bulb never needs replacing and there are no batteries to worry about.
Faraday's Law of Induction explains how the relative motion of the built-in magnet sliding between metal coils charges the light's capacitor.
For prolonged use, just shake for an additional 10 seconds every three minutes. Rugged translucent plastic housing measures 8" long.

I got one for Christmas in 2004. They work really nice and last. Very durable too. The fact that they use a large capacitor keeps you from having to replace a battery, EVER. Even rechargeable batteries have a life. The shaking itself can produce quite a bit of electricity. You may have seen the bicycles that power 100 light bulbs each. However, how long can you pedal for? You can't shake a flashlight long enough to recharge a battery properly. A capacitor is a different story. Though it doesn't have a shelf life, it's power providing life is short, but the flashlight is only meant for short time uses (IE: power outage, light roadside maintenence during the night, etc.).

I also have a funky little flashlight/radio/signal unit that has a Dynamo, solar cell, wall-wart, and a spot for regular batteries. I'd choose that ina long term emergency situation, but for a light in the home and in the car for short emergencies, the HUMMER flashlight works great.

I'll try and find out the brand and find a link for this other unit. they are both pretty cool to have.

[ZAPPER]

Seen them on TV as the "Faraday"? maybe? Seen them in person at Target. Cool idea, kind of weak in the manufacturing (just an opinion) The ones that I had in my hand were like an eight inch model and maybe a 12" version.

My reasoning for calling them weak is that the lens of the flashlight looked to be cheap plastic that may not have been formed all that well. But of course I am comparing it to a well ground glass lens. The other thing that I was kind of disappointed with was the LED. I think that if some effort went into developing the LED into a focused beam type lamp it could do the job better. But what do I know?

All in all I do think that they are pretty cool gizmos and I should have bought them (they only had one each left at the time, but I thought that they were kind of pricey for the perceived quality)

Nope. I don't know the voltage involved. It's probabaly a good thing that I didn't buy any, because I am the kind of guy that would tear it apart to find out.

[Super Warrior]

I used one of those flashlights, the brand name was "Forever flashlight". Used it during katrina when electricity went out.

It was "ok", not great but ok. When charged higher than normal by shaking it really fast for about 3 minutes straight, it produced decent light for a short time before returning to its duller state.

[thecoalman]

My cousin bought a few of those for his kids, great for an emergencey since you know the battery isn't going to be dead but not very practical for any other use. They were pretty dim.

I saw the windup laptop. I too have my doubts as to whether anyone will let that MIT group sell them for $100.00. I guess it is to be Linux based. I've seen a prototype of one, very cool.

Same cousin had a little wind-up radio years ago he'd bring with him on some of our out-in-the-middle-of-no-where excursions and that was very practical. Didn't require much winding.

[Doramius]

Dynamo generators produce high amounts of electricity. You must have a proper storage for the power though. You can't just send the power directly to a battery or unit as you may crank too hard and burn out your equipment. The power needs to be filtered and leveled off. Not cheap unless you can maintain a certain crank speed.

You basically filter the power to a battery and run directly from the battery.

[smearbrick1]

Dynamo generators produce high amounts of electricity. You must have a proper storage for the power though. You can't just send the power directly to a battery or unit as you may crank too hard and burn out your equipment. The power needs to be filtered and leveled off. Not cheap unless you can maintain a certain crank speed.

You basically filter the power to a battery and run directly from the battery.

Capacitors can be used for line conditioning. I imagine that is what you would need.