What is the technology behind wind-up flashlights? How do they work?

Question

How does the winding action charge the battery or mechanism inside to allow the light to illuminate?

Answer 1

The winding spins a small generator that recharges a tiny battery.
Nothing outlandish here...

Answer 2

If you look at it from this perspective, it might seem less like magic: When you wind it, you're expending energy - then it's just stored in the flashlight and used by the LED.

When you spend energy cranking the handle, that energy is being converted into electricity using magnets and coils of wire. The cranking action moves the magnets through the coils exactly as in a generator, except on a much smaller scale. The generated electricity is stored in a battery or capacitor, and is then released through the LED, which uses a lot less electricity than a traditional light bulb does.

Interestingly enough, an electric motor can be used to make electricity like this - motors just normally take electricity and convert it to motion. If you crank the axle of the motor, it will generate electricity at the "inputs" of the motor. That's the principle used by the flashlight.

Answer 3

Wind Up Flashlights

Answer 4

Essentially the two are of the same technology, the flash light where you have to shake it, and the one where you crank it.
The idea is, wrap coils of wire around a magnet so the magnetic flux cuts into the wires and it will generate electricity in the wires. You can do this one of two ways, by moving the magnet itself, or by moving the wires. The crank moves the wires around the magnet so the magnetic lines cut into the wire. The shake the flash light type, causes the magnet move in and out so it cuts into the wires to generate electricity. Once the electricity is generated it can be stored for future use.

Answer 5

Military Grade Tactical Flashlight - http://FlashLight.uzaev.com/?hHkw

Answer 6

The same way the power company makes power.

Moving a magnetic field through a coil of wires induces a current. i.e. a generator

Answer 7

it is called a dynamo motor.
it uses friction between 2 conductive surfaces to create a static electric charge, then it magnifies and stores this charge.

there is more science behind it, but that is the basic.