US3868660A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detector for cross-tie memory
Assignee: United States Department of the Navy
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Filing: 1973-04-10
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Granted: 1975-02-25
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Expires: 1993-04-10
Abstract
Abstract An arrangement for detecting binary information stored in the form of inverted Neel walls in a magnetic serial access memory. A sensing probe above the memory detects variation in the magnetization due to creep as Bloch lines and cross-ties are propagated in the multivibrator to indicate an inverted Neel wall segment.
Inventors
- 👤 Leonard J Schwee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:54
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0866; G01; G01R; G01R19/00; G01R19/165; G01R19/16533; G01R19/16557
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
58 words
Apparatus for detecting magnetic digital information comprising: a stationary magnetic domain wall containing Bloch lines, cross ties and Neel wall segments propagating therein; probe means above said domain wall; and means for introducing a localized field at said probe, whereby said domain wall undergoes wall reversal motion to be sensed by a change of magnetization by said probe.
Claim 2
Dependent Claim
58 words
Apparatus for detecting magnetic digital information comprising: a stationary magnetic domain wall containing Bloch lines, cross ties and Neel wall segments propagating therein; probe means above said domain wall; and means for introducing a localized field at said probe, whereby said domain wall undergoes wall reversal motion to be sensed by a change of magnetization by said probe.
Claim 3
Dependent Claim
35 words
Apparatus as recited in claim 1 further including: multivibrator means coupled to said probe means for receiving said sensed magnetization whereby said multivibrator triggers to cause said localized field to reverse into its opposite direction.
Claim 4
Dependent Claim
28 words
Apparatus as recited in claim 2 further including: conductors carrying current on both sides of said domain wall creating fields to maintain said domain wall in its position.
Claim 5
Dependent Claim
22 words
Apparatus as recited in claim 3 wherein said localized field is in the easy axis direction and said probe comprises a wire.
Claim 6
Dependent Claim
15 words
Apparatus as recited in claim 4 further including oscillator means coupled to said probe means.
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) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |