Patent US3591733A successfully refreshed from Google Patents.
US3591733A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic coupling compensation means for a multielement magnet head
Assignee: International Business Machines Corp
•
Filing: 1969-05-28
•
Granted: 1971-07-06
•
Expires: 1989-05-28
Abstract
Abstract An arrangement for winding the coils of multigap magnetic heads to attenuate readback crosstalk between multiple tracks. A bifilar read coil, both filaments being connected together to provide opposite phases, is supplied on each element forming a gap of the multigap head. Additionally, each filament of the coil is separately wound on a different one of the adjacent elements out of phase with the leakage flux coupling. The resultant threeterminal winding is connected to a center-tapped differential amplifier. Hence, a deliberate one-sided crosstalk overcompensation results in a common mode coupling signal reduced in that the common mode rejection of the differential amplifier attenuates the net coupling signal.
Inventors
- 👤 Louis E Pflughaupt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:42
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/17; G11B20/00; G11B20/24; G11B5/29; G11B5/48; G11B5/58; G11B5/60; G11B5/6005
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
224 words
Apparatus including a multielement magnetic head assembly having a series of closely and uniformly spaced magnetic elements and a single air bearing magnetic body disposed adjacent to said magnetic elements for forming a multiplicity of transducing gaps, in which direct magnetic flux signals are sensed and undesirable leakage flux occurs, comprising: a bifilar main winding signal means having a predetermined number of turns encompassing at least one of said elements; a first filament of said bifilar main winding signal means providing an auxiliary winding that is wound about a first element adjacent to said at least one element; the second filament of said bifilar main winding signal means providing an auxiliary winding that is wound about a second element adjacent to said at least one element; the ratio of the number of turns of each of said first and second filaments relative to the number of turns of said bifilar main winding signal means being a fraction; and a differential amplifier having three input terminals, comprising a common terminal and two terminals of opposite phase with respect to said common terminal, and having two output terminals, said first and second filaments being connected to said common terminal, said first filament being connected to one of said opposite phase terminals, and said second filament being connected to the other one of said opposite phase terminals.
Claim 2
Dependent Claim
224 words
Apparatus including a multielement magnetic head assembly having a series of closely and uniformly spaced magnetic elements and a single air bearing magnetic body disposed adjacent to said magnetic elements for forming a multiplicity of transducing gaps, in which direct magnetic flux signals are sensed and undesirable leakage flux occurs, comprising: a bifilar main winding signal means having a predetermined number of turns encompassing at least one of said elements; a first filament of said bifilar main winding signal means providing an auxiliary winding that is wound about a first element adjacent to said at least one element; the second filament of said bifilar main winding signal means providing an auxiliary winding that is wound about a second element adjacent to said at least one element; the ratio of the number of turns of each of said first and second filaments relative to the number of turns of said bifilar main winding signal means being a fraction; and a differential amplifier having three input terminals, comprising a common terminal and two terminals of opposite phase with respect to said common terminal, and having two output terminals, said first and second filaments being connected to said common terminal, said first filament being connected to one of said opposite phase terminals, and said second filament being connected to the other one of said opposite phase terminals.
Claim 3
Dependent Claim
63 words
Apparatus as in claim 1, including a plurality of said bifilar signal means, each coupled to one of a corresponding plurality of said magnetic elements; and switching means intermediate said plurality of bifilar signal means and said differential amplifier for selectively connecting a desired one of said bifilar signAl means to said differential amplifier, thereby selecting a desired magnetic gap for transducing operation.
Claim 4
Dependent Claim
23 words
Apparatus as in claim 1, wherein each of said first and second filaments constitute a single turn about its respective adjacent magnetic element.
Claim 5
Dependent Claim
51 words
Apparatus as in claim 1, wherein the voltage signal across said first filament that is developed by direct magnetic flux associated with the transducing gap of said at least one element is opposite in phase to the voltage signal across said second filament that is developed by the same magnetic flux.
Claim 6
Dependent Claim
32 words
Apparatus as in claim 1, wherein the net signal between said two input terminals is approximately twice the amplitude of the signal between one of said two terminals and said common terminal.
Claim 7
Dependent Claim
25 words
Apparatus as in claim 1, wherein the transducing gap associated with an adjacent element generates leakage flux that couples to said at least one element.
Claim 8
Dependent Claim
32 words
Apparatus as in claim 6, wherein said first and second filaments are wound so that the signals generated by the direct magnetic flux and by the leakage flux are opposite in phase.
Claim 9
Dependent Claim
47 words
Apparatus as in claim 7, wherein said auxiliary windings are wound so that a compensation signal is generated having approximately two times the amplitude of the leakage flux signal, thereby providing a net compensation signal having approximately the same amplitude and phase as the leakage flux signal.
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) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |