US4455583A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compensation for dimensional changes in a record medium
Assignee: Unisys Corp
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Filing: 1982-06-23
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Granted: 1984-06-19
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Expires: 2002-06-23
Abstract
Abstract A track positioning apparatus for a (floppy) disk record medium to compensate for physical changes in the disk resulting from variations in temperature or humidity. A grating, used to position a read-write head, includes reference marks thereon corresponding to reference tracks on the disk. The grating is stretched or compressed proportionally during a calibration operation to compensate for changes in the flexible disk.
Inventors
- 👤 Ralph H. Schultz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:32
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521; G11B5/5565; G11B21/00; G11B21/02; G11B21/08
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
130 words
Apparatus for compensating for dimensional changes in a recording means comprising: a record medium having first and second reference tracks thereon with a plurality of information tracks therebetween; a flexible member having first and second reference indications with information indications therebetween corresponding to the positions of said reference and information tracks on said record medium; means for selectively positioning a read-write head over one of said tracks and for correspondingly positioning a sensor for sensing one of said indications on said flexible member; means for maintaining said flexible member in tension, said maintaining means movable for expanding and contracting said flexible member; and control means coupled between said read-write head and said sensor for moving said positioning means; and means coupled to said control means for moving said maintaining means.
Claim 2
Dependent Claim
130 words
Apparatus for compensating for dimensional changes in a recording means comprising: a record medium having first and second reference tracks thereon with a plurality of information tracks therebetween; a flexible member having first and second reference indications with information indications therebetween corresponding to the positions of said reference and information tracks on said record medium; means for selectively positioning a read-write head over one of said tracks and for correspondingly positioning a sensor for sensing one of said indications on said flexible member; means for maintaining said flexible member in tension, said maintaining means movable for expanding and contracting said flexible member; and control means coupled between said read-write head and said sensor for moving said positioning means; and means coupled to said control means for moving said maintaining means.
Claim 3
Dependent Claim
50 words
The apparatus of claim 1 wherein the control means includes a controller, a sensing amplifier coupled to said sensor and to said controller, and read amplifier coupled to said read-write head and to said controller, and a positioning amplifier and a servo-amplifier coupled between said controller and said positioning means.
Claim 4
Dependent Claim
27 words
The apparatus of claim 2 wherein said means coupled to said control means includes a compensator control circuit coupled to said maintaining means and to said controller.
Claim 5
Dependent Claim
66 words
The apparatus of claim 1 wherein said control means and said means coupled thereto include means for generating a signal and coupled for moving said positioning means via a positioning amplifier and a servo-amplifier, said signal generating means coupled to said read-write head via a read amplifier, coupled to said sensor via a sensing amplifier and coupled to said maintaining means via a compensator control circuit.
Claim 6
Dependent Claim
14 words
The apparatus of claim 1 wherein said maintaining means includes a pair of rollers.
Claim 7
Dependent Claim
23 words
The apparatus of claim 1 wherein said maintaining means includes a pair of bi-directional motors coupled for expanding and contracting said flexible member.
Claim 8
Dependent Claim
30 words
The apparatus of claim 3 wherein said maintaining means includes a pair of bi-directional motors operably connected to a pair of rollers, said flexible member being connected to said rollers.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-19 | 1987-12-19 | 1988-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-19 | 1991-12-19 | 1992-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-19 | 1995-12-19 | 1996-06-19 | $7700.00 | Window Closed / Lapsed |