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Subject: Re: How to build a windup generator?
Date: Thu, 21 Nov 2002 18:24:47 +0000 (UTC)
NNTP-Posting-Date: Thu, 21 Nov 2002 18:24:47 +0000 (UTC)
User-Agent: tin/1.5.14-20020926 ("Soil") (UNIX) (Linux/2.4.19 (i686))
Michael Black wrote:
> "Dave" (firstname.lastname@example.org) writes:
>> I saw a circuit in a mag using a stepper motor. The motor was hand cranked
>> and the windings individually rectified. The dc outputs were paralleled and
>> had a 1 Farad capacitor across to hold the charge. The application was a
>> wind up LED torch if I remember correctly.
> That's intriguing. But did they make it wind-up, or did you have to keep
> cranking while the flashlight played? The neat thing about the Baygen radio
> (and it's imitators) is that you wind it up, and then the generator is
> powered as the "spring" winds down. I was under the impression it was
> similar to an old windup clock in design.
Some capacitors are getting rather large.
The Ultracap range from EPCOS for example.
10F@2.3V, max discharge current 3A, for around $6us.
Around 26J storage in around 5g.
(around 10% of the energy storage of a NiCd battery of a similar weight,
but a battery that can be charged at that rate weighs at least ten times
http://inquisitor.i.am/ | mailto:email@example.com | Ian Stirling.
"I am the Emperor, and I want dumplings." - Austrian Emperor, Ferdinand I.
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