Patent US4011587A successfully refreshed from Google Patents.
US4011587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary head magnetic recorder for use with a specific record member
Assignee: International Business Machines Corp
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Filing: 1975-09-08
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Granted: 1977-03-08
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Expires: 1995-09-08
Abstract
Abstract An elongated magnetic tape has a pair of longitudinally extending servo track areas, one of which is closer to the longitudinal center of the tape than the other. The lateral space intermediate the servo areas receives data signals, while the space between said one servo area and one edge contains identification and address signals. The tape is particularly adapted for use with rotating head recorders having two gaps on the rotor, with an intergap distance slightly greater than the lateral extent of the servo areas. A recording or write gap precedes an immediately trailing reading or recovery gap. When the rotor gaps pass the one edge in the one servo area, the write gap senses the servo track; while the read gap senses the identification signals. The arrangement is such that prior to the time the write gap reaches the data recording area, the read gap has sensed the identification signals. In a similar manner, when the gaps are leaving the data signal area, the write gap is sensing the other servo area; while the read gap is still sensing data. The longitudinal extent of the servo areas indicates, respectively, beginning of tape (BOT) and end of tape (EOT). A leader portion includes a magnetic coating for facilitating calibrating magnetic recording apparatus to each particular article.
Inventors
- 👤 Nelson K. Arter
- 👤 Thomas F. Eichhorn
- 👤 Clement H. Kalthoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:33
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/008; G11B5/00813; G11B5/00847; G11B5/0086; G11B15/00; G11B15/60; G11B15/602; G11B27/00; G11B27/10; G11B27/102; G11B27/107; G11B27/11; G11B27/13; G11B27/19; G11B27/28; G11B27/30; G11B27/3027; G11B27/32; G11B27/322; G11B2220/00; G11B2220/90
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
316 words
For use with a magnetic tape, a rotating head tape recorder having a rotor for rotating in a first sense and with a recording head closely followed by a readback head for use with an elongate record medium having a leading longitudinal edge crossed first by said heads in close succession with one servo track spaced from said leading edge a distance corresponding to said close spacing of said heads with signals recorded on both sides of said servo track transversely to the elongation of the record medium, the improvement including in combination: signal recording circuits; servo circuits for exercising control over said recorder to position a tape in said recorder; signal readback circuits electrically connected to said readback head for receiving signals therefrom; a tachometer means connected to said rotor for indicating rotational position thereof; and a double-throw, single-pole, electronic switch means responsive to said rotational position indication to switch said recording head between said servo circuits and said recording circuits such that said recording head alternately senses said servo track and records signals respectively as said readback head senses signals intermediate said leading edge and said servo track and then senses signals recorded by said recording head, said tachometer means includes a resettable digital electronic counter generating signal content representing rotor position by a digital count and supplying signals indicative of position including means supplying signals indicating scan of said servo track adjacent said reference edge, said electronic switch means consisting of first and second AND circuits having one common connection to said write head and respective individual connections to said signal recording circuits and said servo circuits and both said AND circuits receiving said servo track signals for alternately switching said write head between said servo circuits and said signal recording circuits, and said signal readback circuits connected to said resettable digital electronic counter for selectively processing signals received from said readback head.
Claim 2
Dependent Claim
316 words
For use with a magnetic tape, a rotating head tape recorder having a rotor for rotating in a first sense and with a recording head closely followed by a readback head for use with an elongate record medium having a leading longitudinal edge crossed first by said heads in close succession with one servo track spaced from said leading edge a distance corresponding to said close spacing of said heads with signals recorded on both sides of said servo track transversely to the elongation of the record medium, the improvement including in combination: signal recording circuits; servo circuits for exercising control over said recorder to position a tape in said recorder; signal readback circuits electrically connected to said readback head for receiving signals therefrom; a tachometer means connected to said rotor for indicating rotational position thereof; and a double-throw, single-pole, electronic switch means responsive to said rotational position indication to switch said recording head between said servo circuits and said recording circuits such that said recording head alternately senses said servo track and records signals respectively as said readback head senses signals intermediate said leading edge and said servo track and then senses signals recorded by said recording head, said tachometer means includes a resettable digital electronic counter generating signal content representing rotor position by a digital count and supplying signals indicative of position including means supplying signals indicating scan of said servo track adjacent said reference edge, said electronic switch means consisting of first and second AND circuits having one common connection to said write head and respective individual connections to said signal recording circuits and said servo circuits and both said AND circuits receiving said servo track signals for alternately switching said write head between said servo circuits and said signal recording circuits, and said signal readback circuits connected to said resettable digital electronic counter for selectively processing signals received from said readback head.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-07 | 1980-09-06 | 1981-03-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-07 | 1984-09-06 | 1985-03-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-07 | 1988-09-06 | 1989-03-08 | $7700.00 | Window Closed / Lapsed |