Skybuck Flying wrote:
Hello,

I find this a very interesting product:

http://www.tomshardware.com/news/cor...gpu,31977.html


It claims that it's fans "levitate".

Does this mean it no longer requires any oil and thus no more cleaning
because of dust+oil+black smoke stuff frictions ?

I consider this a major breakthrough, now PCs won't require any more oil
to function.

Perhaps oil to produce them, but after that, no more oil needed LOL.

Such a re-assurance ! Really it's very nice to know. In case the oil
runs out some day ! LOL.

Bye,
Skybuck.

The OEM is likely to be Sunon.

See page 3. The design relies on magnetic attraction.
There is still a bearing.

http://www.sunon.com/tw/products/pdf/maglev.pdf

Now if you look at this diagram and page, you'll see
that the claims are slightly different. The fan
actually has more conventional elements to it.
The fan is not quite as magical as it looks in
the Sunon PDF.

http://www.comet.bg/files/custom/MagLev_scheme.jpg

( http://www.comet.bg/?cid=105&NewsId=961 )

"Prevents dust penetration,
increases lubrication circulation"

From another web page

"The unique feature of SUNON's MagLev motor fan
is that the path of the flan blades during
operation is magnetically controlled by Sunon's
patented MagLev System. The result is that the
shaft and bearing have no direct contact during
operation and so experience no friction no matter
how the fan is oriented. This means that the
characteristic abrasion noises of worn-out components
are not produced and also allows a service life
of 50,000 hours or even longer at room temperature.
"

Some fans at work had a service life of 25000 hours.
We would tell customers to do a preventative replacement
of the fans in the product, every three years of 24 hour
per day system operation (the fans could be replaced
with the power still on). These Sunon fans would be good
for six years, if you believe the advertising material.

The device is not a fluid dynamic bearing, and isn't
sealed on the ends. It just has dust caps. Your guess
is as good as mine, as to what the lubrication circulation
pattern looks like.

The Panaflo fans, used a sealed bearing with a trade
name of "hydro wave". Which I believe is a fluid dynamic
bearing. Rather than a dust cap, that's an attempt at
a sealed bearing. While I don't have a datasheet
(and Panaflo was bought by NMB), a quick Google lists
some of those fans as having a 50000 hour service life.

So if I held two fans in my hand, a Panaflo and
a Sunon Maglev, which would you buy ? :-) Which
has the least flaky explanation for how it works ?
You decide. The Sunon looks like it has a pretty
conventional bearing. And when real world considerations
are taken into account, the bearing will not be
exactly frictionless. It will be "close to" frictionless.

HTH,
Paul