EP0189503A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Servowriter system for magnetic disc drives
Assignee: Pioneer Research Inc
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Filing: 1985-02-01
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Granted: —
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Expires: 2005-02-01
Abstract
Abstract A portable servowriter system for writing a closed clock track and servo tracks on one or more of the fixed discs of a fixed disc magnetic disc drive without the aid of a mechanical head positioner; and which is also capable of writing a closed clock track and servo tracks (either on a dedicated disc surface or of the embedded form) on one or more of the discs of a rotating disc magnetic disc drive with the aid of a mechanical positioner.
Inventors
- 👤 James K. Berger
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 17:08
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/58; G11B5/596; G11B5/59633; G11B5/59655
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
127 words
A servowriter system for writing odd and even servo information in servo tracks on a magnetic disc, said system including: an electromagnetic servo head mounted on a movable arm for writing the odd and even servo information in the servo tracks on the magnetic disc; a motor for driving the movable arm so as to position the servo head with respect to the disc; a microprocessor control unit; a programmable servo generator connected to said microprocessor control unit and to said servo head for introducing the odd and even servo information to said servo head to be written in the servo tracks on said disc; and a programmable servo positioner system connected to said microprocessor and to said motor for controlling the position of said servo head.
Claim 2
Dependent Claim
127 words
A servowriter system for writing odd and even servo information in servo tracks on a magnetic disc, said system including: an electromagnetic servo head mounted on a movable arm for writing the odd and even servo information in the servo tracks on the magnetic disc; a motor for driving the movable arm so as to position the servo head with respect to the disc; a microprocessor control unit; a programmable servo generator connected to said microprocessor control unit and to said servo head for introducing the odd and even servo information to said servo head to be written in the servo tracks on said disc; and a programmable servo positioner system connected to said microprocessor and to said motor for controlling the position of said servo head.
Claim 3
Dependent Claim
80 words
The servowriter system defined in claim 1, in which said microprocessor control unit causes said programmable servo positioner system initially to drive the arm of said servo head to the outer radius of said disc and subsequently to cause the servo head to move toward the inner radius of said disc under velocity servo control, and simultaneously causes said servo generator to introduce even servo information to the servo head to be written over the entire surface of said disc.
Claim 4
Dependent Claim
66 words
The servowriter system defined in claim 2, in which said microprocessor control unit then causes said servo positioner system to drive the arm of said servo head to the outer radius of said disc, and then causes said servo generator to introduce odd servo information to said servo head to be written in selected sectors around said disc in a track adjacent to said other radius.
Claim 5
Dependent Claim
89 words
The servowriter system defined in claim 3, in which said microprocessor control unit causes said servo positioner system to position the servo head on boundaries between the odd and even servo information on the disc, and said servo positioner system includes position servo circuitry for maintaining the servo head on said boundaries, and in which-said microprocessor control unit causes said servo generator to introduce odd servo information to said servo head to be written in successive tracks extending from the outer radius to the inner radius of the disc.
Claim 6
Dependent Claim
67 words
The servowriter system defined in claim 4, in which said microprocessor unit determines the number of said successive tracks on which the odd servo information was written, and said microprocessor unit introduces a bias control signal to said positioner system to change the number of said successive tracks to be subsequently established by said servo positioner system so as to correspond to a predetermined number of tracks.
Claim 7
Dependent Claim
83 words
The servowriter system defined in claim 5, in which said microprocessor control unit again drives the arm of said servo head to the outer radius of the disc and again causes the servo head to move toward the inner radius of said disc under velocity servo control by said servo positioner system, and in which said microprocessor control unit causes said servo generator to introduce even servo information to the servo head again to be written over the entire surface of said disc.
Claim 8
Dependent Claim
66 words
The servowriter system defined in claim 6, in which said microprocessor control unit again causes said programmable servo positioner to drive said arm to the outer radius of the disc, and said microprocessor control unit again causes said servo generator to introduce odd servo information to said servo head to be written in_- selected sectors around said disc in the track adjacent to said outer radius.
Claim 9
Dependent Claim
93 words
The servowriter system defined in claim 7, in which said microprocessor control unit then causes said servo positioner system to position the servo head on the boundaries between the odd and even servo information on the disc, and in which said servo positioner system includes position servo circuitry for maintaining the servo head on the boundaries, and in which said microprocessor control unit then causes said servo generator to introduce odd servo information to said servo head to be written in successive tracks from the outer to the inner radius of the disc.
Claim 10
Dependent Claim
41 words
The servowriter system defined in claim 8, in which said microprocessor control unit controls the servo generator to cause the servo head to write odd and even servo information in successive ones of said tracks in selected sectors around the disc.
Claim 11
Dependent Claim
66 words
The servowriter system defined in claim 1, wherein said servo head includes an electromagnetic clock head for writing clock signals in a closed format on a clock track on the disc; and wherein said servo generator includes a clock writer circuit connected to said microprocessor control unit and to said clock head for introducing clock information to said clock head to be written on the disc.
Claim 12
Independent Claim
60 words
A method for writing odd and even servo information in servo tracks on a magnetic disc having an outer radius and an inner radius, which method comprises causing a servo head to write odd and even servo information in selected tracks on the disc while positioned on the boundaries of odd and even servo information previously written on the disc.
Claim 13
Independent Claim
60 words
A method for writing odd and even servo information in servo tracks on a magnetic disc having an outer radius and an inner radius, which method comprises causing a servo head to write odd and even servo information in selected tracks on the disc while positioned on the boundaries of odd and even servo information previously written on the disc.
References Cited (Backward Citations)
EP0042931A2
Cited
EP0084709A1
Cited
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