Richard D Lesage

US Patent:

6751044, Jun 15, 2004

Filed:

Oct 29, 1999

Appl. No.:

09/430614

Inventors:

Steven W. Meeks - San Jose CA
Richard D. LeSage - Longmont CO
David S. McMurtrey - Loveland CO
Peter R. Svendsen - Colorado Springs CO
W. Craig Tomalty - Colorado Springs CO

Assignee:

Maxtor Corporation - Longmont CO

International Classification:

G11B 5596

US Classification:

360 7703, 360 51

Abstract:

A magneto-optical clock head is disclosed. The magneto-optical clock head allows a longitudinally recorded clock track to be read from a disk surface from a position outside of a head-disk assembly (HDA). The clock track has sections of alternating magnetization which define transitions. Importantly, the magneto-optical clock head is used to sense the transitions using the transverse Kerr effect, as opposed to the longitudinal Kerr effect as used in one prior technique. In one embodiment, the magneto-optical clock head includes a light source for generating a p-polarized beam which is aligned in such a manner that it strikes the clock track. A reflected beam is then produced which has an intensity that varies based upon the direction of the magnetization of the sections of alternating magnetization of the clock track due to the transverse Kerr effect. A detector is provided to detect the intensity variations in the reflected beam and to ultimately generate a clock signal which is provided to transducers to allow them to appropriately write servo information onto their respective disk surfaces. A method for optically reading a clock signal stored within a clock track which is written onto a disk surface that is located within a head disk assembly of a disk drive is also provided.

US Patent:

7483269, Jan 27, 2009

Filed:

Oct 2, 2006

Appl. No.:

11/542607

Inventors:

David S. McMurtrey - Loveland CO, US
Richard D. LeSage - Longmont CO, US

Assignee:

Maxtor Corporation - Scotts Valley CA

International Classification:

G06F 1/16

US Classification:

361685

Abstract:

An adapter which allows two or more hard disk drives to conduct self-testing in a single test rack slot is provided. Testing can be individually controlled for the various HDDs in a slot. Peltier cell devices or other cooling or heating devices can be controlled to achieve individualized temperature control for HDDs in the test rack slot.

US Patent:

7529055, May 5, 2009

Filed:

Mar 29, 2006

Appl. No.:

11/392350

Inventors:

Jason Laks - Ft. Collins CO, US
David Scott McMurtrey - Loveland CO, US
Brian Rigney - Louisville CO, US
Richard Dennis Lesage - Longmont CO, US

Assignee:

Maxtor Corporation - Longmont CO

International Classification:

G11B 21/02

US Classification:

360 75, 369 4748

Abstract:

An apparatus is provided for writing reference patterns on a data storage disk of a disk drive. The disk is rotated by a spindle motor. A back EMF sense circuit generates a sequence of zero crossing signals from back EMF sensed on windings of the spindle motor over each revolution of the spindle motor. The sequence of zero crossing signals define a corresponding sequence of zero crossing periods of time between successive zero crossing signals. A Phase Locked Loop (PLL) circuit generates a timing signal in response to comparison of a feedback signal to the zero crossing signals. The PLL circuit also compensates for repeatable variation among the sequence of zero crossing periods over each revolution of the spindle motor so that the timing signal is substantially independent of the repeatable variation among the sequence of zero crossing periods. A recording pattern generator writes reference patterns on the disk in response to the timing signal as the disk is rotated by the spindle motor. Related methods of making a disk drive are also provided.

US Patent:

7855848, Dec 21, 2010

Filed:

Oct 2, 2006

Appl. No.:

11/542686

Inventors:

Duong Hong Nguyen - Broomfield CO, US
Tan Chin Kiong - Singapore, SG
Richard LeSage - Longmont CO, US
Lee Teng Boon - Singapore, SG

Assignee:

Seagate Technology LLC - Scotts Valley CA

International Classification:

G11B 27/36
G11B 21/02

US Classification:

360 31, 360 75

Abstract:

Detection of head disk interference is provided by monitoring a hard disk drive characteristic related to disk rotation rate. A number of characteristics can indicate HDI. These include the magnitude of decreases in rotation rate, changes in the time-derivative (time-rates of change) of rotation rate or other changes in time-profiles of rotation rate, changes in spin motor current, differences between maximum and minimum values of spin motor current, changes in the time-derivative (time-rates of change) of spin motor current or other changes in time-profiles of spin motor current or combinations or indicators thereof. These approaches to detecting HDI provide several potential advantages. Detection of HDI can be achieved relatively early in a test or other procedure, can be performed relatively rapidly, can distinguish HDI from at least some other anomalies and can indicate the location and/or magnitude of HDI occurrences.