H-6586-K Magnetic Disk Unit

For this unit, Hitachi decided to exploit its own in-house disk manufacturing capability, and eliminate the previous 14-inch disk, develop a new 9.5-inch disk, and use a thin-film head for the first time. An access mechanism, which was high-speed and high-precision at the time, was achieved by using a linear mechanism with a ceramic rail for the actuator, and developing a voice coil motor with a powerful neodymium magnet. The volume of the HDA was successfully reduced by a significant margin with high-density mounting design around the HDA, and twice the capacity per unit was achieved by installing 8 HDA's in the same area as the IBM3380K.