EP0063935A1
Expired / Lapsed
EP
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Method and apparatus for disk drive head positioning
Assignee: Iomega Corp
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Filing: 1982-04-23
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Granted: —
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Expires: 2002-04-23
Abstract
Abstract A servo encoding scheme and demodulation circuit for control of the position of a read/write head (12) with respect to a magnetic recording disk is disclosed. First and second signals (A, B) of like polarity are recorded preceding each data field on the sector of the disk. The signals are summed (36) to provide automatic gain control to the servo loop to compensate for variations in read-back amplitude, while the difference between the two signals is measured (40) and used to provide an indication of departure of the head from the centre of the disk track, for control of a servo motor (18) for the head (12).
Inventors
- 👤 Douglas F. Ballard
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 21:26
CPC Classifications
G; G11; G11B; G11B21/00; G11B21/02; G11B21/10; G11B21/106; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521; G11B5/5526; G11B5/553; G11B5/5547; G11B5/58; G11B5/596; G11B5/59605; G11B5/59622
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
127 words
Apparatus for the control of the position of a read/write head (12) with respect to a magnetic recording disk (10), the disk (10) having recorded thereon at regular intervals first and second position signals (A,B) of identical polarity, the apparatus comprising servo motor means (18) for moving the head (12) with respect to the disk (10), summing means (36) for adding the first and second position signals, and for controlling variable amplification (38) of the signals in accordance with the value of the sum, and comparator means (40) for comparing the values of the first and second signals (A,B) and for generating a servo signal applied to the motor (18) as a result of said comparison, such that the first and second signals tend to be equalized.
Claim 2
Dependent Claim
127 words
Apparatus for the control of the position of a read/write head (12) with respect to a magnetic recording disk (10), the disk (10) having recorded thereon at regular intervals first and second position signals (A,B) of identical polarity, the apparatus comprising servo motor means (18) for moving the head (12) with respect to the disk (10), summing means (36) for adding the first and second position signals, and for controlling variable amplification (38) of the signals in accordance with the value of the sum, and comparator means (40) for comparing the values of the first and second signals (A,B) and for generating a servo signal applied to the motor (18) as a result of said comparison, such that the first and second signals tend to be equalized.
Claim 3
Independent Claim
101 words
A method of control of the position of a read/ write head with respect to first and second position information signals of identical polarity permanently recorded on a magnetic recording surface, said first and second signals being spaced from one another on said surface, comprising the steps of summing the first and second signals and controlling variable amplification of the signals in accordance with the sum such that the sum remains substantially constant and comparing the signals to one another and controlling the position of the head with respect to the signals such that the difference between the signals is minimized.
Claim 4
Independent Claim
101 words
A method of control of the position of a read/ write head with respect to first and second position information signals of identical polarity permanently recorded on a magnetic recording surface, said first and second signals being spaced from one another on said surface, comprising the steps of summing the first and second signals and controlling variable amplification of the signals in accordance with the sum such that the sum remains substantially constant and comparing the signals to one another and controlling the position of the head with respect to the signals such that the difference between the signals is minimized.
References Cited (Backward Citations)
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