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Anonymous
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# Posted: 20 Jul 2011 08:38pm
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I went on a trip to Costa Rica back in 1992 and they had ceiling fans which were operated by pulling a chain down. It was I think operated by some kind of counter weight and used no electricity. You had to re-pull it every 30 minutes or so but it worked just fine. I have a buddy living there, I will ask him to look it up and re-post.
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bobrok
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# Posted: 21 Jul 2011 06:35pm
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Quoting: Anonymous I went on a trip to Costa Rica back in 1992 and they had ceiling fans which were operated by pulling a chain down. It was I think operated by some kind of counter weight and used no electricity. You had to re-pull it every 30 minutes or so but it worked just fine. I have a buddy living there, I will ask him to look it up and re-post.
If you can find some information on that it would be awesome. Please keep us up to date on your findings.
Thanks.
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Brknarow
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# Posted: 22 Jul 2011 06:26pm
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I found this site while considering the feasability of running a black pvc pipe up the south side of a cabin to draw cooler air through vents on the northern by cross circulation. http://poormanguides.blogspot.com/2009/06/solar-air-conditioning.html.
I didn't see any counters for keeping moisture from forming inside the underground pipe though. That moisture is what Legionnaires Disease formed in you know.
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UltraViolet
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# Posted: 10 Aug 2011 11:42am
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I have also been searching for a NE ceiling fan for about 10 years. Been down lots of rabbit holes trying to engineer the thing myself. You'd think there'd be a market for such an appliance. Hope someone solves it soon!
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bobrok
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# Posted: 10 Aug 2011 12:51pm
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Ultraviolet:
I am the OP of this thread. If you read from the beginning there is a link to the DIY forum where I had been conversing with lots of ppl for quite a while on the subject.
Can you share your experiences in trying to engineer this with us? Even tho I kind of signed of that other forum I am still very interested in any new information or experiences you'd like to share. Thanks.
Bob
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UltraViolet
Member
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# Posted: 10 Aug 2011 02:03pm
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Bob,
Thanks - I've followed the DIY forum for several years regarding the NE fan.
None of my own attempts have proved successful - so no great insights to report.
I keep hoping the Baygen FreePlay (wind-up radio) folks will turn their attention to creating a fan.
UV
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JohnInNY
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# Posted: 31 Dec 2011 10:52am
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I've just read all these threads and I have to say, I'm VERY surprised this monster you've all been talking about DOESN'T exist. I found this discussion by looking for the same thing you're looking for, bobrok. My need is for an old 1880 house I bought here in northern NY. The furnace is oil and forced air. If the power goes out, I was screwed. I finally had an unvented propane heater (Mr. Heater) installed, as I couldn't afford the cost of all the fluing for a wood stove.
Meanwhile, this very cold morning at 7:00 a.m., the power went out. I've never been so glad I made the Mr. Heater investment!! The power was only out for 3 hours but there are stories about this area loosing power for 9 days. When faced with the potential of -40 degrees, the thought of having no power is a nightmare.
In any case, as you well know, the ceiling about the propane heater is VERY warm while the floors are freezing. I'm looking for something to stir the air with no power too. My mind goes back to a carousel kind of Christmas decoration we had. You lit candles below and the heat would rise, causing the "fan" on top to spin.
With the enormouse amount of heat rising, wouldn't the same principle as that carousel work?? I mean, it could be an extremely lightweight alluminum ceiling fan that would probably spin extremely fast... or at least enough to stir a decent amount of air.
To me, the idea seems so simple... but it's not come up in any of the threads. Is there something I'm not thinking of with the idea??
John
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MtnDon
Member
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# Posted: 31 Dec 2011 11:00am - Edited by: MtnDon
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The rising hot air is making the carousel "fan" move. Not the other way around. It might look pretty but it is not going to move an additional air.
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MtnDon
Member
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# Posted: 31 Dec 2011 11:37am
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Something like this Stirling engine powered fan could be made to work when there is a source of heat available.
Moriya Hot Air Fan
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JohnInNY
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# Posted: 31 Dec 2011 03:06pm
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I still don't see it. If that carousel "fan" was able to spin fast enough and the fins were tilted properly, it seems to me it would have to blow air as a fan does. Granted, it would blow upwards, so all it could do is push the hot air further up and cause it to bounce off the ceiling and then back down somewhat. Maybe not, though. I may have to rig something up to see for myself! :)
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MtnDon
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# Posted: 31 Dec 2011 03:54pm
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I wish you luck on this. The old saying you can't get something for nothing does stand especially true in the world of physics and "work", though. Making the hot rising air go someplace other than where it naturally wants to go, or with increased velocity requires "work". The first obstacle will be in overcoming friction within the bearings. You're never going to get more "work" out of a system than what is put into the system.
As soon as you try to extract some "work" from the freely rotating blades they will slow down. The freely rising air will strike the blades but as the air is not contained in a duct the air will spill out to the sides without imparting much force to the blades.
A fan freely spinning in rising hot air above a hot object is not going to spin faster than the rising air and will not be able to give a boost to the upward velocity. Such a fan may act somewhat as a diffuser but I don't see it being able to move air horizontally enough to help with getting an air exchange with another room happening.
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JohnInNY
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# Posted: 31 Dec 2011 05:27pm
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Yes, after I wrote the last post I sat and really contemplated it. I love engineering but I lack in formal physics education. I see your point now. I doubt too that the blades could push any more air than what is actually rising. I guess now I see why the idea hasn't come up in any of these replies. Maybe with multiple gears, though?
Someone really needs to come up with a solution. There is obviously a demand for some NE ceiling fan and the inventor would probably do very well in sales! I know I'd buy one right now, if I could! Thanks, MtnDon.
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Rifraf
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# Posted: 31 Dec 2011 05:46pm - Edited by: Rifraf
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You could rig one right though the roof and put a sister fan up there so the inside fan is driven by wind :)
Seriously though, why wouldnt the clock system work on a larger scale, a hand crank to tighten a coil spring and a gearbox to only let it uncompress at a constant slow rate.
Big enough spring with the right gearbox could give a long decompression time I would think.
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MtnDon
Member
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# Posted: 31 Dec 2011 05:50pm
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Quoting: JohnInNY Maybe with multiple gears, though?
A gear train has friction loses.
If you try to speed up the driven fan, that requires more work input. Think bicycle in high gear.
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Rifraf
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# Posted: 31 Dec 2011 05:56pm - Edited by: Rifraf
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here are a few interesting links
http://www.leevalley.com/en/gifts/page.aspx?c=&p=50246&cat=4,104,55967
listserv.repp.org/pipermail/stoves_listserv.repp.org/2007-February/005604.htm
http://www.google.com/patents/about?id=67BGAAAAEBAJ&dq=1194007
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bobrok
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# Posted: 2 Jan 2012 09:52am
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Quoting: JohnInNY I've just read all these threads and I have to say, I'm VERY surprised this monster you've all been talking about DOESN'T exist. I found this discussion by looking for the same thing you're looking for, bobrok.
Hi JohnInNY and welcome to the forum from one upstate NYer to another! I think most of your questions have already been addressed above but I'd like to offer a synopsis of what I have learned through the DIY connections I made.
The poster on DIY garyofcourse and I communicated quite a bit off forum as he proceeded through his graduate course and as best as I can summarize their main issue was a sustainable source of torque (power) to operate their fan. They did build one; I saw photos, but it worked for only 2-3 minutes on some sort of torsion spring power that they had devised at the last minute. Their other problem was that the course was ending and they didn't have enough time to do further experimentation with other sources of power, so the professor rewrote the course so that all they had to prove was a working fan, albeit for two minutes, as concept of principal. They've all moved on and I have fallen out of touch. The idea was to patent this and offer it to third world contries where electrical power is non-existant.
I also made contact through that forum with another person who claims to actually make working fans on order, powered by a pull chain/spring type of mechanism, and he claims that his fans will run for a sustainable period of time. I've spoken on the phone with this person but have not pursued anything further because I didn't want to blindly order one, send payment, and be disappointed or worse, ripped off. I would have visited were it not for the fact that we are several states apart. I still have this information and if anyone thinks it worth pursuing perhaps we can open another discussion.
Thanks for your post, and I hope that my information has been helpful.
bob
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bobrok
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# Posted: 6 Jan 2012 05:22pm
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I know I had saved a photo or two somewhere. Had to dig it out from my old laptop.
This is the prototype fan that was engineered by the student I was communicating with. It worked, but barely.
Just thought I would share this with the mechanical minds of this forum both for observation and critique...
the off grid fan that almost was
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tthompson
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# Posted: 29 Apr 2012 10:31am
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I've read all you postings on both sites over the last couple hours after thinking about it myself, and looking at the math, I can't see how it could be done for any length of time. Short term is easy, weight falls, fan spins. Done. So, given a fall of say 6 feet (72) inches and a final pulley diameter of 2.5", on a 1:1 ratio, you'll get 9 revolutions. So, how fast do you want the blade to spin? I've read that 100rpm is about the minimum for a useful fan.
Using that number, you need a ratio of 1:666 for each hour. Let's say you wanted to spin the fan for 8 hours. That means if you would need a final ration of 1:5333.
You would need at least 4 gears, each with a 1:8.6 ratio to pull it off. What kind of weight would you need to overcome that friction and inertia? I shudder to think.
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sparky1
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# Posted: 29 Apr 2012 11:22am
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RCA made Victroler's 100 years ago--their system was (hand cranked spring-- Might something similar work?
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Randoo
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# Posted: 29 Apr 2012 11:35am
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I visited an Amish shop that used ceiling fans powered by compressed air. The owner was kind enough to show me the setup; a gas powered engine turned a compressor that filled his tank. After he shut off the valve I noticed the fans were still turning a few minutes later (at a slower speed). He stated that they did not require much pressure to turn, and would run for about 5 minutes on the pressure in the lines.
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MtnDon
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# Posted: 29 Apr 2012 04:15pm
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I can see that working, but is it worth having to run a gasoline engine? There are many motors designed over the years that operate on compressed air. Some have enough power to be used a propel small utility vehicles. The catch with these is having a sufficient supply of compressed air to do the job at a reasonable cost.
Victrolla's only had to turn a lightweight disc, and still only long enough to play a tune or two. I can remember winding the crank on one as a kid. The novelty (to me) wore off in a hurry. You couldn't even get enough run time, IMO, to have a nap while being cooled by the fan moving air.
Something like this should make us think about how many things we take for granted are really not easy to have or achieve without electricity.
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BRL
Member
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# Posted: 29 Apr 2012 08:17pm
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If you are going to be burning wood anyway maybe a thermoeletric generator and a low wattage fan like don posted would be the ticket!
http://tegpower.com/
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fred
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# Posted: 9 May 2012 04:47pm
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Hello,
I am not a member and don't mean to butt in, but FYI...i watched an episode of The Shark Tank last month. I know, silly show but cool inventions sometimes.
There was a women on the show who had invented a wind-up ceiling fan, I kid you not. She was asking the group for money to fund the invention. I was searching for it when I found this site.
The group of rich people were interested. That is all I know. I dont have any more info than that, and I wont be back to this site but I thought i would contribute. Bye
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fred
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# Posted: 15 May 2012 02:29pm
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Hello again,
I didn't think I would be back but I found some more stuff for you guys. I also tried searching for more info for that supposed wind-up fan featured on that silly show. I could not find anything either. I wonder now if it was fake.
But you guys sound very mechanical...try this website I found:
http://www.free-energy-info.co.uk/Chapter6.pdf
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fred
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# Posted: 15 May 2012 02:47pm
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Ooops,
Start with the intro page. http://www.free-energy-info.co.uk
Have fun!
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Force_Multiplier
Member
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# Posted: 26 Jun 2012 04:42am - Edited by: Force_Multiplier
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this is something I've also been looking for...
In Panama I also saw ceiling fans that didn't use electricity, some that had a pull chain, and I think others that used a winding key similar to a clock...
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pondjumpr
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# Posted: 2 Jul 2012 03:51pm
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Thia may not be quite what you are looking for but i was at BJ's (Like Sam's or Costco) the other night and saw a battery powered cieling fan for a large outdoor umbrella. I thought of this thread. It said it used either 6 or 8 "D" batteries. I can't imagine it would run very long but if it ran on 12v or something close, it may be able to be rigged up on a battery bank. It was probably 30" or better and looked almost like any cieling fan in a home, it just had the ability to attatch to the underside of an umbrella on the pole.
I found it interesting.
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