Hitachi GST Assigned Three Patents

Asymmetrical air bearing surface for head slider in HDDs

Hitachi Global Storage Technologies BV, Amsterdam Netherlands, The Netherlands, has been assigned a patent (8,270,115) developed by Oscar J. Ruiz, San Jose, CA, for an "asymmetrical air bearing surface for a head slider in hard disk drives."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A method and apparatus for a head slider air bearing surface (ABS) in hard disk drives that mitigate fly height deviations. The invention mitigates these problems by providing an ABS of the head slider with elongated asymmetrical features that extend substantially parallel to the direction of the airflow caused by the rotating magnetic disk, in one or both of the inner diameter (ID) and outer diameter (OD) positions of the head slider with respect to the magnetic disk. The head slider may be produced with a two step etch process, as opposed to a three step etch process. By reducing the number of etching steps, the head slider of the invention can be produced at lower costs and in less time as fewer masks and chamber pump-down steps are required."

The patent application was filed on May 28, 2009 (12/474,164).

Implementing data confidentiality
and integrity of shingled written data

Hitachi Global Storage Technologies BV, Amsterdam, The Netherlands, has been assigned a patent (8,271,801) developed by Cyril Guyot, San Jose, CA, for an "implementing data confidentiality and integrity of shingled written data."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A method, apparatus and a data storage device are provided for implementing data confidentiality and integrity of data stored in overlapping, shingled data tracks on a recordable surface of a storage device. A unique write counter is stored for each zone written to the recordable surface of the storage device. An encryption key is used together with the write counter information and a logical block address to encrypt each sector being written, and to decrypt all sectors being read. An individual sector is decrypted, obtaining the write counter information and reading the data sector. A message authentication code is stored for each zone. All sectors of the zone are read to perform integrity check on a sector."

The patent application was filed on Nov. 19, 2009 (12/622,400).

Flex cable assembly damper

Hitachi Global Storage Technologies BV, Amsterdam, The Netherlands, has been assigned a patent (8,270,120) developed by five co-inventors for a "flex cable assembly damper."

The co-inventors are Jeffrey Kerner, Kirk B. Price, Robert C. Reinhart, Edgar D. Rothenberg, San Jose, CA, and Jr-Yi Shen, Sunnyvale, CA.

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A flex cable assembly for a head stack assembly of a hard disk drive comprises a flex cable for conducting data signals from the head stack assembly to a connector. The flex cable comprises a dynamic loop section between a termination for the head stack assembly and the connector. A constrained layer damper is attached adjacently to an area of the flex cable that is configured to receive the coupler. The constrained layer damper extends into the dynamic loop section of the flex cable."

The patent application was filed on Nov. 30, 2007 (11/998,511).