Справочник Пользователя для Samsung 3.5" hard disk drives

DISK DRIVE OPERATION 

 

SpinPoint V40 Product Manual

25

 

 
The disk stack assembly in the SpinPoint V40 hard disk drive consists of 1 or 2 disks and disk spacers 
secured on the hub of the spindle motor assembly by a disk clamp.  The aluminum-alloy disks have a 
sputtered thin-film magnetic coating. 
 
A carbon overcoat lubricates the disk surfaces to prevent heads and media wear due to the repeated head 
contacts with disk surfaces during head take-offs and landings.  Contact between heads and disk surfaces 
occurs only in the landing zone outside of the data area, when the disks are rotating at slower than normal 
speed during spin up or down.  The landing zone is located at the inner diameter of the disk, far beyond the 
last cylinder of the data area. 
 

 
The head stack assembly consists of an E-block/coil sub-assembly, read/write heads, a flexible circuit, and 
bearings.  The E-block/coil sub-assembly is assembled with an E-block and over-molded coil.  Read/write 
heads are mounted to spring-stainless steel flexures that are then swage mounted onto the E-block arms. 
 
The flexible circuit connects the read/write heads with the PCBA via a connector through the base casting.  
The flexible circuit contains a read/write Preamplifier IC. 
 

 
The rotary voice coil motor consists of upper and lower permanent magnets and magnetic yokes fixed to the 
base casting and a rotary over-molded coil on the head stack assembly.  Each magnet consists of two 
alternating poles and is attached to the magnet yoke.  Rubber crash stops mounted on the over-molded coil 
and a magnetic yoke physically prevent the head(s) from moving beyond the designed inner boundary into 
the spindle or off the disk surface. 
 
Current from the power amplifier induces a magnetic field in the voice coil.  Fluctuations in the field around 
the permanent magnets move the voice coil so that heads can be positioned in the requested cylinder. 
 

 
Heads fly very close to the disk surfaces.  Therefore, it is very important that air circulating within the drive 
be maintained free of particles.  Samsung HDAs are assembled in a purified air environment to ensure 
cleanliness and then sealed with a gasket.  To retain this clean air environment, the SpinPoint V40 is 
equipped with a re-circulating filter, which is located in the path of the airflow close to the rotating disk and 
is designed to trap any particles that may develop inside HDA.