axis
of the flying piano wire Ø 1,5 mm
350
rpm
(Flash animation - in fact the LEDs are brighter ...)
(Flash animation - in fact the LEDs are brighter ...)
updated on 08/22/07 |
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page
created June 2004 |
Version 1.2
Or how to produce electricity and light from a cup of hot water ...
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axis
of the flying piano wire Ø 1,5 mm
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350
rpm
(Flash animation - in fact the LEDs are brighter ...) |
Changes to version 1.1
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major changes include the use of miniature ball bearings mounted on a shaft piano wire Ø 1.5 mm, the fixing of 4 permanent magnets on the periphery of the wheel, the assembly of 4 coils to supply electrical power 2 LED low current.
Additional Supplies
- 4 bearings (flanged) Ø 1.5
x Ø 5 (Ø x 6.5) which can be ordered from SORB ref.: (F) 691X
- 4 cubic magnets 5 mm Neodymium available at SuperMagnete under number W-05-G
- 4 coils from air relay 12 V automotive, and removing the nucleus (enameled
copper wire Ø 0.2 mm, L = 27 mH, R = 74 ohms)
- 2 LEDs at low current (2mA) found at Conrad as ref. 18 69 02-33 (Low-Current
LED Ø 5 mm)
Principle
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the principle is the "dynamo" bike that bears his name wrong, because it is part of a small generator: whenever a magnet approaches the coil, there generates a emf - when the magnet moves away, it creates an electromotive force in the opposite direction - (see also version 3.7)
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The adjustment was fairly easy to do on this model because it combines both power and speed sufficient to feed one or two LEDs: 15 mW at 500 rpm on a cup of boiling water - (converted to mechanical power which we must subtract the losses due to friction - diagram p,V left).
To use the two alternating current, the LEDs are mounted upside down: one turns on when the voltage is positive and the other when it becomes negative, the persistence of vision through the rest ... In practice LEDs start to shine from 250 rpm, a linear velocity of 1.5 m / s, and produce the maximum amount of light a little over 500 rpm - about a cup of hot water they shine in thirty minutes.
Some bad images of this development Simplified Stirling Engine
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rotating
motor, the light emitted by the LED appears pinkish white overexposed
in this picture ...
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the
4 coils are connected in series to obtain a voltage as high as
possible
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Focus
on a magnet when it passes between the coils
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this is a version equipped with a lower plate
ep 2 mm, a shaft Ø 2 mm and a relief valve (see models 1.1 , 3.5, 3.6,
Otona no Kagaku, and FAQ)
Red LEDs are replaced with white LED (1) producing
a more pleasing light, for example, to read his diary (2)... 
placed
on a cup of boiling water and two ice cubes on the top shelf,
it runs about 500 rpm and produces an electrical output of around
30 mW
vibration visible in this video are
probably due to the interaction of magnets with coils and a balance of
approximately
they are amplified by the stacking of different components: turntable + cup
hot water + Stirling engine, and by moving the center of gravity to the top
(coils)
sequence clocked at 30 frames / sec
(other Stirling engines in generator current version : 3.7 , Otona
no Kagaku , JAXA)
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(1) LED red or white? ... The answer is in the FAQ
(2) the illumination produced is 1.5 lux, split almost evenly over the surface of the paper, which is 10 times that of the full moon at the zenith
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