US3603939A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic domain propagation arrangement
Assignee: AT&T Inc
•
Filing: 1969-07-30
•
Granted: 1971-09-07
•
Expires: 1989-07-30
Abstract
Abstract Optimum size of single wall domains in a magnetic sheet is reduced by applying to each face of the sheet a high permeability overlay of prescribed thickness. Increased packing densities and operating margins result.
Inventors
- 👤 Andrew H Bobeck
- 👤 Henry E D Scovil
- 👤 Alfred A Thiele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 01:02
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0858; G11C19/085; H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/26; H01F10/265
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
85 words
Apparatus comprising a sheet of magnetic material in which a single wall domain having a radius r can be moved, said domain having a flux density Bo, first and second layers of relatively high permeability material contiguous first and second surfaces of said sheet, said first layer having a flux density B1 and a thickness t such that said layer magnetically saturates locally in the presence of a domain having a radius r 2t (B1/B0) , said second layer having at least a thickness t.
Claim 2
Dependent Claim
85 words
Apparatus comprising a sheet of magnetic material in which a single wall domain having a radius r can be moved, said domain having a flux density Bo, first and second layers of relatively high permeability material contiguous first and second surfaces of said sheet, said first layer having a flux density B1 and a thickness t such that said layer magnetically saturates locally in the presence of a domain having a radius r 2t (B1/B0) , said second layer having at least a thickness t.
Claim 3
Dependent Claim
19 words
Apparatus in accordance with claim 1 wherein said second layer has a thickness for essentially unlimited flux handling capability.
Claim 4
Dependent Claim
25 words
Apparatus in accordance with claim 1 in combination with means for moving said domain in said sheet and means for detecting domains in said sheet.
Claim 5
Dependent Claim
19 words
A combination in accordance with claim 3 also including means for introducing single wall domains into said sheet selectively.
Claim 6
Dependent Claim
51 words
Apparatus comprising a sheet of magnetic material in which single wall domains can be moved, each of said domains having associated therewith a magnetostatic field and means comprising a magnetic layer coupled to said sheet and having a thickness for maintaining constant said magnetic field for domains of significantly different sizes.
Claim 7
Dependent Claim
51 words
Apparatus comprising a sheet of magnetic material in which single wall domains can be moved, each of said domains having associated therewith a magnetostatic field and means comprising a magnetic layer coupled to said sheet and having a thickness for maintaining constant said magnetic field for domains of significantly different sizes.
References Cited (Backward Citations)
US3092813A
Cited
US3503055A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |