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I have a small string powered helicopter. While waiting for the computer to finish long compilations (like now), I pull the string but hold the helicopter, so that the propellers give me a nice breeze. The only problem is that they stop abruptly, when the pulling action is done.
I need the turning
part (a gyro which gathers the power I put in, or the propeller itself, perhaps with an external ring) to disengage (in some kind of ratchet type of action) from the propulsion.
The propeller could be made of lightweight fabric (like the handheld electric fans that are sold lately), and the whole thing could be created as a simple lightweight toy.
Rubber band winder
http://www.legoeduc....aspx?ID=648&bhcp=1 [afinehowdoyoudo, Dec 04 2008]
Rubber-band fan
http://www.sei.ie/S...ings_to_Make/P5.pdf lamest incarnation ever [afinehowdoyoudo, Dec 04 2008]
string-powered rubber band winder
http://www.google.c...&dq=5390763#PPA1,M1 [afinehowdoyoudo, Dec 04 2008]
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can anyone draw this for me? thanks. |
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The thing about a flywheel (gyro as you say) is that to store energy it must be heavy &/or be turning very fast. Neither the fan nor a hand crank is particularly fast, and you say lightweight. A spring that you wind up might work better. Thinking on this, and rubber-band powered model airplanes come to mind. A rubber band, with propeller on one end, and a winding mechanism on the other (e.g. geared-up hand crank (such as the ones commonly used by rubber-band-airplane enthusiasts), or a version with a pull-string or a squeeze-handle). |
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