Disk Drive Operation
WA31273A / WA32543A / WA33203A / WA32163A / WA31083A / WA32162A5-3
5-1-4 Disk Stack Assembly
The disk stack assembly in the
Winner 3A WA31273A / WA32543A / WA33203A / WA32163A /
WA31083A, Winner 2A WA32162A
hard disk drive consists of 1, 2 or 3 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 protects the disk magnetic surfaces to prevent head and media wear due
to head contact with the disk surfaces during head take-off and landing. Head contact with
the disk surface occurs only in the landing zone outside of the data area, when the disks are
not rotating at full speed. The landing zone is located at the inner diameter of the disk, far
beyond the last cylinder of the data area.
5-1-5 Head Stack Assembly
The head stack assembly consists of an actuator/coil sub-assembly, read/write heads, a
flexible printed circuit and bearings. The actuator/coil sub-assembly is assembled with
actuator and over molded coil. Read/write heads are mounted to spring-stainless steel
flexures that are then swage mounted onto the rotary positioning assembly arms of the
actuator.
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.
5-1-6 Rotary Positioning Assembly
The rotary positioner, or rotary voice coil motor, is a SAMSUNG proprietary design that
consists of upper and lower permanent magnetic yokes fixed to the base casting and a
rotary overmolded coil on the head stack assembly. The magnet consists of two alternating
poles glued to the magnet yoke. Rubber crash stops mounted on the upper magnet yoke
and base casting prevent the head from being flown into the spindle or off of 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
on the requested cylinder.
5-1-7 Air Filtration System
It is very important that air circulating within the drive be free of particles. SAMSUNG HDA’s
(head/disk assemblies) are assembled in a Class 100 purified air environment to ensure cleanliness. To
retain this clean air circulation, the Winner 3A WA31273A / WA32543A / WA33203A / WA32163A /
WA31083A, Winner 2A WA32162A is equipped with a recirculating filter, which cleans the air within
the HDA. The recirculating filter traps any particles which may be generated during head landing or
