levitating fans?

[_Will_]

ok...was looking thru my cyberguy's mag....(was for my dad but theres lots of overclocking stuff in here...so i decided that he didn't really need it :D )

and looking thru case fans i found some "magnetic levitation fans"...around 12 bucks

sez "low power consumption" "friction-free(as u might guess)" and "extremely quiet"

as far as quietness its usually the air hittn' stuff that makes the noise...not really the fan itself, am i right?

but anyway...i though it was pretty interesting


they're made by sunon, btw...go up only to 60X60X25 tho....

if this is old news...just go ahead and shoot me...but if not...its something sorta interesting to check out ;)

[_Will_]

as far as specs for CFM...voltage/amp ratings and so forth....magnizines are usually pretty vague...and don't skimp in this particular description

tomorrow i'll try n do a search and see if i can find more info

[ButcherUK]

Acttualy a reasonable amount of fan noise is due to the bearings, depending on constrained the airflow path is.

[YMAN]

I heard this before but I did now know it was sunnon that
made them! I must do reasearch!!!

Dont worry, I will not shoot you C:\Windows\Desktop\PICS\Emoticons\mates.gif

[Robbie]

there probably "air bearings" Airbearing use magnets in them to allow things to literaly ride on a cushion of air. The machines that I work on have these. They use them on the polygon motors so that they run quiter.

They basicaly work like on the theory that "like magnet poles will replel one another."

Ever try and push two speakers together? Same Idea.

Rob

[_Will_]

http://www.sunon.com.tw/

sad to say...while the noise levels are low (30ish) the performance isn't that great (up to 25 CFM

[r0ckstarbob]

like a magnetic impeller on a mag drive water pump. works pretty good but doesn't deal with resistance well. hm. ah well. good to see up here anyhow.

[ButcherUK]

Originally posted by r0ckstarbob
like a magnetic impeller on a mag drive water pump. works pretty good but doesn't deal with resistance well. hm. ah well. good to see up here anyhow.
Well no not really, a magdrive pump is more like a standard fan, the impellor spins on a fixed shaft (it's water lubed so you can forgo bearings), and has fixed magnets on the shaft and a rotating magnetic field induced by electromagnets in the housing. A normal fan has fixed magnets in the shaft section and then external coils - that's jsut a brushless fan. magnetic levitation basically means no contact between the shaft and the housing, it's a good plan for low noise but probably hard to configure so it works.

[The Overclocker]

most air noise in small fans are produced by the propulsion made, bearings or brush, but with large fans the noise is simply air shifting noise

[_Will_]

i knew i was at least partially right ;)