International Business Machines Corporation

Hitachi Global Storage Technologies

Sunao Nemoto

David W Albrecht

Kiyoshi Satoh

Hiroki Kitahori

Gregory Michael Frees

Masakazu Sasaki

A motor having reduced deformation due to a temperature change. The motor is an outer ring type motor having a bearing cartridge, which integrates the shaft, ball bearings and sleeve. The outer periphery of the sleeve is attached to the inner periphery of the hub at a bonding region positioned axially between the ball bearing holding portions. The bonding portion includes a stress reducing region. The diameter of the hub within the stress reducing region is not uniform in order to reduce the stress generated between the outer periphery of the sleeve and the inner periphery of the hub due to thermal expansion.

Spindle motor-having improved bonding between its bearing cartridge and hub

An attachment structure and method for a disk drive apparatus for making the coupling resonance frequency of a hard disk drive the same whether one disk is loaded or a plurality of disks are loaded based upon parameters obtained from a simulation model. The modeling of a coupling vibration for one disk and for two disks is performed using a coupling vibration model of a linear two degree-of-freedom system. The component parts of a spindle motor providing a spring constant K,are adjusted so that the resonance frequency determined by coupling that of a spindle motor with that of the disk(s) is made much the same whether one disk or two disks are loaded. This adjustment enables stable track following to be secured without the need for adding dummy disks and other parts.

Disk drive apparatus, attachment structure, and attachment method

Growing community of inventors

Fujisawa, Japan

Sunao Nemoto