US4369476A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-track recording head assembly with electromagnetic cross-talk neutralization
Assignee: Orbital Sciences LLC
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Filing: 1980-07-25
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Granted: 1983-01-18
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Expires: 2000-07-25
Abstract
Abstract A high track density recording head assembly which eliminates cross-talk in high track density recording systems by positioning very thin neutralization heads between each pair of adjacent recording heads. The neutralization heads are provided with air gaps aligned with the gaps in the adjacent heads and have coils wound to develop a polarity opposite to that in the adjacent recording head. The neutralization head flux thus produced cancels the recording head lateral fringing flux that is responsible for recording interference in the adjacent recording tracks.
Inventors
- 👤 Herbert Karsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:10
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/29
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
169 words
A multi-track recording head assembly with electromagnetic cross-talk and crossfeed neutralization comprising: a first recording head and a second recording head for developing varying magnetic fluxes for recording a first track and a second track, respectively, on a recording medium moving relative said heads; a first neutralization head juxtaposed between said first recording head and said second recording head and proximate to said first recording head for developing a varying magnetic flux having a polarity opposite to that developed by said first recording head for neutralizing a portion of said flux by said first recording head which would otherwise be recorded as crossfeed and cross-talk on said second track; and a second neutralization head juxtaposed between said first neutralization head and said second recording head for developing a varying magnetic flux of opposite polarity of said flux developed by said second recording head for neutralizing a portion of said flux developed by said second recording head which would otherwise be recorded as crossfeed and cross-talk on said first track.
Claim 2
Dependent Claim
169 words
A multi-track recording head assembly with electromagnetic cross-talk and crossfeed neutralization comprising: a first recording head and a second recording head for developing varying magnetic fluxes for recording a first track and a second track, respectively, on a recording medium moving relative said heads; a first neutralization head juxtaposed between said first recording head and said second recording head and proximate to said first recording head for developing a varying magnetic flux having a polarity opposite to that developed by said first recording head for neutralizing a portion of said flux by said first recording head which would otherwise be recorded as crossfeed and cross-talk on said second track; and a second neutralization head juxtaposed between said first neutralization head and said second recording head for developing a varying magnetic flux of opposite polarity of said flux developed by said second recording head for neutralizing a portion of said flux developed by said second recording head which would otherwise be recorded as crossfeed and cross-talk on said first track.
Claim 3
Dependent Claim
102 words
A multi-track recording head assembly as claimed in claim 1 wherein: said first recording head includes a first magnetic core provided with a first air gap, and a first coil wound around said first magnetic core, whereby a fringing magnetic flux is developed at said first air gap when a current flows through said first coil; and said second recording head includes a second magnetic core provided with a second air gap, and a second coil wound around said second magnetic core, whereby a fringing magnetic flux is developed at said second air gap when a current flows through said second coil.
Claim 4
Dependent Claim
160 words
A multi-track recording head assembly as claimed in claim 2 wherein: said first neutralization head includes a third magnetic core provided with a third air gap, and a third coil wound around said third magnetic core in a direction opposite to the winding of said first coil around said first core, whereby a fringing magnetic flux is developed at said third air gap which neutralizes a portion of said fringing magnetic flux developed by said first air gap, when current flows through said third coil; and said second neutralization head includes a fourth magnetic core provided with a fourth air gap, and a fourth coil wound around said fourth magnetic core in a direction opposite to the winding of said second coil around said second core, whereby a fringing magnetic flux is developed at said fourth air gap which neutralizes a portion of said fringing magnetic flux developed by said second air gap, when current flows through said fourth coil.
Claim 5
Dependent Claim
49 words
A multi-track recording head assembly as claimed in claim 3, wherein the current flowing through said first coil is in phase with the current in said third coil and wherein the current flowing through said second exciting coil is in phase with the said current in said fourth coil.
Claim 6
Dependent Claim
35 words
A multi-track recording head assembly as claimed in claim 4 wherein said first coil and said third coil are connected in series and wherein said second coil and said fourth coil are connected in series.
Claim 7
Dependent Claim
26 words
A multi-track recording head assembly as claimed in claim 1 further comprising a static shield disposed between said first neutralization head and said second neutralization 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) | 1986-01-17 | 1986-07-19 | 1987-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-17 | 1990-07-19 | 1991-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-17 | 1994-07-19 | 1995-01-18 | $7700.00 | Window Closed / Lapsed |