US3838406A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magneto-resistive magnetic domain detector
Assignee: Verizon Laboratories Inc
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Filing: 1973-03-23
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Granted: 1974-09-24
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Expires: 1993-03-23
Abstract
Abstract A cylindrical magnetic domain detector is formed of a pair of series coupled magneto-resistive elements which are disposed in magnetic coupling relationship with a cylindrical magnetic domain memory position, each detector element in quadrature arrangement can be piecewise distributed in sections of arbitrary length. An undesirable signal due to the rotating magnetic field generates an extraneous signal in the respective elements which differ in phase by 180*. The arrangement of these elements results in suppressing these extraneous signals at the output of the detector.
Inventors
- 👤 M Urban
- 👤 L Cohen
- 👤 B Shortt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:21
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/09; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0866
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
182 words
A detector of magnetic domains being circulated in a crystal of magnetic oxide between discrete positions determined by an overlay permalloy bar pattern, with the domains being moved under drive action from an in-plane magnetic field rotating at a drive frequency comprising: a domain sensing magneto-resistive device formed of a continuous magneto-resistive segment arranged into series coupled elements which are oriented to form one pair of elements in quadrature relationship relative to each other, said continuous magnetoresistive segment being located on the crystal in proximity to a discrete magnetic domain position to register a change in resistance caused by the magnetic influence of a domain moved onto said discrete domain position; wherein at least one element in said continuous magneto-resistive segment is separated into series coupled distributed pieces which are oriented parallel to each other to respond with similar resistance changes; and means coupled to the magneto-resistive segment to produce an output signal representative of the change in resistance of the quadrature related to elements in the continuous magnetoresistive segment when a magnetic domain is located at said discrete magnetic domain position.
Claim 2
Dependent Claim
182 words
A detector of magnetic domains being circulated in a crystal of magnetic oxide between discrete positions determined by an overlay permalloy bar pattern, with the domains being moved under drive action from an in-plane magnetic field rotating at a drive frequency comprising: a domain sensing magneto-resistive device formed of a continuous magneto-resistive segment arranged into series coupled elements which are oriented to form one pair of elements in quadrature relationship relative to each other, said continuous magnetoresistive segment being located on the crystal in proximity to a discrete magnetic domain position to register a change in resistance caused by the magnetic influence of a domain moved onto said discrete domain position; wherein at least one element in said continuous magneto-resistive segment is separated into series coupled distributed pieces which are oriented parallel to each other to respond with similar resistance changes; and means coupled to the magneto-resistive segment to produce an output signal representative of the change in resistance of the quadrature related to elements in the continuous magnetoresistive segment when a magnetic domain is located at said discrete magnetic domain position.
Claim 3
Dependent Claim
34 words
The magnetic domain detector as claimed in claim 1 wherein the elements of said continuous magneto-resistive segment are arranged in a V-shaped configuration where each arm of the V configuration has the same length.
Claim 4
Dependent Claim
57 words
The magnetic domain detector as claimed in claim 1 wherein the elements of said continuous magneto-resistive segment are arranged in a U-shaped configuration formed of a pair of arms and a bight located between the arms, where each arm is of the same length and where the bight is twice as long as one of the arms.
Claim 5
Dependent Claim
35 words
The magnetic domain detector as claimed in claim 1 wherein said continuous magneto-resistive segment is formed of two pairs of quadrature related elements with each element being oriented at a predetermined angle to each other.
Claim 6
Dependent Claim
29 words
The magnetic domain detector as claimed in claim 4 wherein one pair of said quadrature related elements are oriented at 45* to the second pair of quadrature related elements.
Claim 7
Dependent Claim
156 words
In an improved magnetic domain sensing circuit wherein said domains are circulated in a crystal of magnetic oxide between discrete positions determined by an overlay permalloy bar pattern with the domains being moved under drive action from an in-plane magnetic field rotating at a drive frequency, said circuit including means for converting changes in resistance in the sensing circuit into a voltage variation for use by external processing equipment, the improvement comprising: a shaped domain sensing magneto-resistive device electrically connected to said current source, said device having at least two pairs of quadrature related segments which are series connected, with each pair being arranged in quadrature relative to the other pair and located on the crystal in proximity to a discrete magnetic domain position, both of said segments being located and responsive to the magnetic influence of a domain moved onto said discrete domain position whereby extraneous signals dUe to the rotating magnetic field are suppressed.
Claim 8
Dependent Claim
156 words
In an improved magnetic domain sensing circuit wherein said domains are circulated in a crystal of magnetic oxide between discrete positions determined by an overlay permalloy bar pattern with the domains being moved under drive action from an in-plane magnetic field rotating at a drive frequency, said circuit including means for converting changes in resistance in the sensing circuit into a voltage variation for use by external processing equipment, the improvement comprising: a shaped domain sensing magneto-resistive device electrically connected to said current source, said device having at least two pairs of quadrature related segments which are series connected, with each pair being arranged in quadrature relative to the other pair and located on the crystal in proximity to a discrete magnetic domain position, both of said segments being located and responsive to the magnetic influence of a domain moved onto said discrete domain position whereby extraneous signals dUe to the rotating magnetic field are suppressed.
Claim 9
Dependent Claim
56 words
The magnetic domain circuit as claimed in claim 6 wherein the segments of said device are arranged in a U-shaped configuration formed of a pair of arms and a bight element located between the arms, where each arm is of the same length and where the bight is twice as long as one of the arms.
Claim 10
Dependent Claim
45 words
The magnetic domain circuit as claimed in claim 6 wherein at least one segment of said magneto-resistive device is separated into distributed series coupled pieces which are oriented parallel to each other to respond with similar resistance changes introduced by the in-plane magnetic drive field.
Claim 11
Dependent Claim
28 words
The magnetic domain circuit as claimed in claim 8 wherein one pair of said quadrature related segments are oriented at 45* to the second pair of quadrature segments.
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) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |