Samsung M8 Disk Stack Assembly, Head Stack Assembly, Air Filtration System, Load/Unload Mechanism

5.1.3Disk Stack Assembly

The disk stack assembly in the Spinpoint M8 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 glass disks have a sputtered thin-film magnetic coating.

5.1.4Head Stack Assembly

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.

5.1.5Voice Coil Motor and Actuator Latch Assemblies

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. Pawl latch and rubber crash stops mounted on 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.

5.1.6Air Filtration System

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 M8 hard disk drive 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.

5.1.7Load/Unload Mechanism

Portable computer is exposed to heavy handling environment comparing with desk top computer. Load/Unload mechanism provides to protect data loss caused by head hitting to disk due to the abnormal shock and vibration in the transportation and handling. When power is shut down, head will move to parking position on the ramp.

Spinpoint M8 Product Manual REV 2.3 25