Harddisk is vacuum?

[paladin_yang]

A netie said Harddisk's inside is vacuum. Just because there is a pellicle named "vacuum pelicle".
Who knows the reality.

 

[dhlucke]

This has got to be a really bad online translation.

Try using another translator. Babblefish if you haven't already tried.

</font color=red><i><font color=red>GOD</font color=red> <font color=blue>BLESS </font color=blue><font color=red>AMERICA

 

[Ned_Flanders]

Who knows the reality

...brilliant :lol:

_______________________
<A HREF="http://www.moviewavs.com/MP3S/TV_Shows/Simpsons/flanderssong.mp3" target="_new">Audio Sig</A>

 

[RichPLS]

Actually, a hard drive has to have air pressure inside to work properly, the read head requires this, and thus has a vent with a filter to equalize out air pressure. This is why their is a ceiling spec usually around 10,000-feet for hard drives based on minimum air density.
Much of the detailed design of the disk drive and its electronics also assumes air cooling. There doesn't have to be a lot of air circulation. And PCs are hopelessly bad thermal designs, with very little air flow in many areas, but there has to be some.


_____________________________________________
<font color=red> And the sign says "You got to have a membership card to get inside" Huh
So I got me a pen and paper And I made up my own little sign </font color=red>

 

[Crashman]

There's a reason why Seagate is always advertising on Careerbuilder for engineers with hydrodynamics specialties. Reread what Rich said.

<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

 

[paladin_yang]

Thank you very much.
Please forgive my poor English.

 

[sjonnie]

Is this because the actuator has to take the air movement into account? Presumably if you have a disk spinning at 10,000rpm its whipping up quite a hurricane inside the disk. Then the actuator has to move through this with millisecond timing and micrometer precision to try and get to the correct track! Must be quite a challenge.

<A HREF="http://www.anandtech.com/myanandtech.html?member=114979" target="_new">My PCs</A> 😎

 

[RichPLS]

Repeat, it is not true that a disk drive contains a vacuum, as the system relies on air pressure inside the drive to support the heads at a designed height while the disk is in operation. A hard disk drive requires a certain range of air pressures in order to operate properly. The distance between the read head and platter is around 90 nanometers. If the air pressure is too low, the air will not exert enough force on the flying head, the head will not be at the correct height, and there is an increased risk of head crashes and data loss. There are specially sealed and pressurized hard drives which are needed for reliable high-altitude and space operations, above about 10,000 feet. Some newer drives include flying height sensors to detect if the air pressure is too low or high, and temperature sensors to alert the system to heat problems.

Now in creating these drives, extreme lengths has to be performed when making and assembling these drives so small dust sized particles do not get inside these drives and become lodged between the read head and platter. This can cause contact which disrupts the magnetic platter and can lead to crashes.

_____________________________________________
<font color=red> And the sign says "You got to have a membership card to get inside" Huh
So I got me a pen and paper And I made up my own little sign </font color=red>