US5289097A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spindle control method and apparatus for disk drive
Assignee: HGST Netherlands BV
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Filing: 1992-08-18
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Granted: 1994-02-22
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Expires: 2012-08-18
Abstract
Abstract A spindle motor control method and apparatus for spindle motor control are provided for use in a direct access storage device. A plurality of operational modes of the direct access storage device are detected. The operational modes of the direct access storage device include start-up and idle operational modes and predetermined critical operational modes that include reading of data and reading of servo information. A pulse width modulation (PWM) mode control for applying driving current to the spindle motor is provided responsive to detecting a start-up or an idle operational mode. A linear mode control for applying driving current to the spindle motor is provided responsive to detecting one of the predetermined critical operational modes. During operation of the disk file, a small percentage of the overall file power-on time is spent performing critical file operations so that substantial power savings are achieved by the PWM mode control. Also since the integrity of the data transferred is critical, the error rate reduction that results by operating in the linear mode during the critical file operations is advantageous.
Inventors
- 👤 Kevin J. Erickson
- 👤 Richard Greenberg
- 👤 Douglas W. Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:47
CPC Classifications
G; G11; G11B; G11B19/00; G11B19/02; G11B19/20
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
123 words
A spindle motor control method for a direct access storage device including a multi-phase, brushless spindle motor and first and second half bridge power driver circuits; comprising the steps of: detecting start-up and idle operational modes of the direct access storage device; applying a pulse width modulation (PWM) signal for gating said first driver circuit for applying PWM driving current to the spindle motor responsive to detecting an idle operational mode; applying the PWM signal for gating said first driver circuit responsive to detecting a start-up operational mode of the disk file; detecting predetermined critical operational modes of the direct access storage device; and applying a linear driving current to the spindle motor responsive to detecting one of said predetermined critical operational modes.
Claim 2
Dependent Claim
123 words
A spindle motor control method for a direct access storage device including a multi-phase, brushless spindle motor and first and second half bridge power driver circuits; comprising the steps of: detecting start-up and idle operational modes of the direct access storage device; applying a pulse width modulation (PWM) signal for gating said first driver circuit for applying PWM driving current to the spindle motor responsive to detecting an idle operational mode; applying the PWM signal for gating said first driver circuit responsive to detecting a start-up operational mode of the disk file; detecting predetermined critical operational modes of the direct access storage device; and applying a linear driving current to the spindle motor responsive to detecting one of said predetermined critical operational modes.
Claim 3
Dependent Claim
40 words
A spindle motor control method as recited in claim 1, wherein said step of detecting start-up and idle operational modes of the direct access storage device includes the step of detecting an idle operational mode at normal spindle operating speed.
Claim 4
Dependent Claim
37 words
A spindle motor control method as recited in claim 1 further includes the step of applying a linear mode of operation for said second driver circuit responsive to detecting a reading operational mode of the disk file.
Claim 5
Dependent Claim
37 words
A spindle motor control method as recited in claim 1 further includes the step of applying a linear mode of operation for said second driver circuit responsive to detecting a writing operational mode of the disk file.
Claim 6
Dependent Claim
43 words
A spindle motor control method as recited in claim 1 further includes the steps of generating a speed error signal by comparing an actual spindle speed with a predetermined spindle speed and generating a control signal responsive to said generated speed error signal.
Claim 7
Dependent Claim
46 words
A spindle motor control method as recited in claim 5 further includes the steps of detecting a current sense feedback signal and generating PWM and linear second error signals responsive to identifying a difference between said generated control signal and said detected current sense feedback signal.
Claim 8
Dependent Claim
84 words
Apparatus for spindle motor control comprising: means for detecting a plurality of operational modes of the disk file; said plurality of operational modes including start-up, idle, data reading, servo information reading, and writing operational modes; means for generating a pulse width modulation (PWM) mode of spindle motor control responsive to a detected start-up or idle operational mode by said detecting means; and means for generating a linear mode of spindle motor control responsive to a detected data reading operational mode by said detecting means.
Claim 9
Dependent Claim
84 words
Apparatus for spindle motor control comprising: means for detecting a plurality of operational modes of the disk file; said plurality of operational modes including start-up, idle, data reading, servo information reading, and writing operational modes; means for generating a pulse width modulation (PWM) mode of spindle motor control responsive to a detected start-up or idle operational mode by said detecting means; and means for generating a linear mode of spindle motor control responsive to a detected data reading operational mode by said detecting means.
Claim 10
Dependent Claim
37 words
Apparatus for spindle motor control as recited in claim 7 wherein said means for generating a linear mode of spindle motor control further are responsive to a detected servo information reading operational mode by said detecting means.
Claim 11
Dependent Claim
35 words
Apparatus for spindle motor control as recited in claim 7 wherein said means for generating a linear mode of spindle motor control further are responsive to a detected writing operational mode by said detecting means.
Claim 12
Dependent Claim
54 words
Apparatus for spindle motor control as recited in claim 7 wherein said PWM and linear modes of spindle motor control include means for means comparing an actual spindle speed with a predetermined spindle speed for generating a speed error signal and means for generating a control signal responsive to said generated speed error signal.
Claim 13
Dependent Claim
46 words
Apparatus for spindle motor control as recited in claim 10 further including means for detecting a current sense feedback signal and means for identifying a difference between said generated control signal and said detected current sense feedback signal to generate PWM and linear second error signals.
Claim 14
Dependent Claim
23 words
Apparatus for spindle motor control as recited in claim 11 further includes half bridge driver circuits coupled to a multi-phase, brushless spindle motor.
Claim 15
Dependent Claim
26 words
Apparatus for spindle motor control as recited in claim 12 wherein said PWM mode control includes means for gating out said generated linear second error signal.
Claim 16
Dependent Claim
26 words
Apparatus for spindle motor control as recited in claim 12 wherein said linear mode control includes means for gating out said generated PWM second error signal.
Claim 17
Dependent Claim
134 words
A disk file comprising: a housing; a plurality of disk surfaces mounted in said housing for simultaneous rotation about an axis; a plurality of transducer heads mounted for movement across said disk surfaces for reading and writing information to said disk surface; a control system for controlling a spindle motor; said control system including; means for detecting a plurality of operational modes of the disk file; said plurality of operational modes including start-up, idle, data reading, servo information reading, and writing operational modes; means for applying a pulse width modulation (PWM) driving current to said spindle motor responsive to a detected start-up or idle operational mode by said detecting means; and means for applying a linear driving current to said spindle motor responsive to a detected data reading operational mode by said detecting means.
Claim 18
Dependent Claim
134 words
A disk file comprising: a housing; a plurality of disk surfaces mounted in said housing for simultaneous rotation about an axis; a plurality of transducer heads mounted for movement across said disk surfaces for reading and writing information to said disk surface; a control system for controlling a spindle motor; said control system including; means for detecting a plurality of operational modes of the disk file; said plurality of operational modes including start-up, idle, data reading, servo information reading, and writing operational modes; means for applying a pulse width modulation (PWM) driving current to said spindle motor responsive to a detected start-up or idle operational mode by said detecting means; and means for applying a linear driving current to said spindle motor responsive to a detected data reading operational mode by said detecting means.
References Cited (Backward Citations)
US4485337A
Cited
US4600868A
Cited
US4751441A
Cited
US4783774A
Cited
US5003415A
Cited
US4988933A
Cited
US4970610A
Cited
US5119250A
Cited
US5128813A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-02-21 | 1997-08-23 | 1998-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-02-21 | 2001-08-23 | 2002-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-02-21 | 2005-08-23 | 2006-02-22 | $7700.00 | Window Closed / Lapsed |