clock charing usb devices

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Alec_t

Jul 7, 2015
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Welcome to EP!
I doubt the clock wind-up mechanism stores enough energy to do much charging :(.
According to Wikipedia, "adults of good average fitness average between 50 and 150 watts for an hour of vigorous exercise." Clock-winding is hardly a vigorous pursuit, so assuming you can wind up the clock in 20 seconds, at most you will likely have stored 50/180 = 0.28 Watt.Hrs of energy in the clock spring. Allowing for inefficiencies in the charging process you are left with ~ 0.2 Watt.Hrs. A cell-phone battery typically holds ~10 Watt.Hrs when fully charged.
 

Gryd3

Jun 25, 2014
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Welcome to EP!
I doubt the clock wind-up mechanism stores enough energy to do much charging :(.
According to Wikipedia, "adults of good average fitness average between 50 and 150 watts for an hour of vigorous exercise." Clock-winding is hardly a vigorous pursuit, so assuming you can wind up the clock in 20 seconds, at most you will likely have stored 50/180 = 0.28 Watt.Hrs of energy in the clock spring. Allowing for inefficiencies in the charging process you are left with ~ 0.2 Watt.Hrs. A cell-phone battery typically holds ~10 Watt.Hrs when fully charged.
I had to link this... it's just too (almost) related .
>

Lots of energy from motion is not an easy task...
 

James Matheson

May 30, 2016
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Welcome to EP!
I doubt the clock wind-up mechanism stores enough energy to do much charging :(.
According to Wikipedia, "adults of good average fitness average between 50 and 150 watts for an hour of vigorous exercise." Clock-winding is hardly a vigorous pursuit, so assuming you can wind up the clock in 20 seconds, at most you will likely have stored 50/180 = 0.28 Watt.Hrs of energy in the clock spring. Allowing for inefficiencies in the charging process you are left with ~ 0.2 Watt.Hrs. A cell-phone battery typically holds ~10 Watt.Hrs when fully charged.
i don't want to insult you so I wont answer but in response if you don't like what I write then don't reply to me
 

Gryd3

Jun 25, 2014
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i don't want to insult you so I wont answer but in response if you don't like what I write then don't reply to me
Other's on here aren't so tight lipped.
What about Alec_T's post screamed "I don't like your post" ?
We don't mean to insult anyone on here even when they ask question pertaining to projects that are way too far outside of their current understanding of how electronics work. We donate our time to helping people even when they seem helpless and ignorant. I've also seen some incredible patients shown towards people who don't read the responses or listen to the advice given. Hopefully you are not one of these people.

Before you damage yourself, how about you share some details on how you want it to work, how much energy you wish to store, and what kind of budget you have in mind for your project.
We have very knowledgeable people from all over the world.
 

BobK

Jan 5, 2010
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Did you look at that video? He produced 21 Watt Hours of energy over about 2 minutes to toast that piece of bread.

How much does it take to charge a typical cell phone?

1A at 5V = 5W for about 2 hours, so 10 Watt Hours.

That is about half of what the cyclist produced. If winding your clock takes 1/2 as much effort as the cyclist in the video put out, then you are in the right range to charge a cell phone. If it is nowhere near that, like Alec_t suggested, then you have nowhere near enough energy stored in the clock spring, as he said.

He did not insult you, he merely pointed out, correctly, that your project is not feasible.


Bob
 
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davenn

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Sep 5, 2009
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thread closed
really bad attitude

@James Matheson

when you get an attitude adjustment, please start another thread

Dave
 
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