Patent US3128418A successfully refreshed from Google Patents.
US3128418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetically latched switch operator
Assignee: AT&T Inc
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Filing: 1960-07-13
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Granted: 1964-04-07
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Expires: 1980-07-13
Abstract
No abstract record available.
Inventors
- 👤 Frank A Zupa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:27
CPC Classifications
C; C21; C21D; C21D1/00; C21D1/18; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01H; H01H51/00; H01H51/01; C21D8/00; C21D8/12; C21D8/1244
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
84 words
A MAGNETICALLY LATCHABLE SWITCH OPERATOR COMPRISING A MAGNETIC CORE OF ABOUT 1% CARBON STEEL, A COIL FOR ENERGIZING THE CORE, AN ARMATURE ASSOCIATED WITH THE CORE AND FOR CONTROLLING CONTACTS, SAID CORE HAVING A ROCKWELL 30-N SCALE HARDNESS OF 54 TO 64, AND A HIGH RETENTIVITY COUPLED WITH A HIGH PERMEABILITY, THE COERCIVE FORCE OF THE CORE BEING FROM 20 TO 27 OERSTEDS AND THE RESIDUAL FLUX DENSITY FROM 10,000 TO 13,500 GAUSSES BASED ON AN APPLIED MAGNETIZING FORCE OF AT LEAST 70 OERSTEDS.
Claim 2
Dependent Claim
84 words
A MAGNETICALLY LATCHABLE SWITCH OPERATOR COMPRISING A MAGNETIC CORE OF ABOUT 1% CARBON STEEL, A COIL FOR ENERGIZING THE CORE, AN ARMATURE ASSOCIATED WITH THE CORE AND FOR CONTROLLING CONTACTS, SAID CORE HAVING A ROCKWELL 30-N SCALE HARDNESS OF 54 TO 64, AND A HIGH RETENTIVITY COUPLED WITH A HIGH PERMEABILITY, THE COERCIVE FORCE OF THE CORE BEING FROM 20 TO 27 OERSTEDS AND THE RESIDUAL FLUX DENSITY FROM 10,000 TO 13,500 GAUSSES BASED ON AN APPLIED MAGNETIZING FORCE OF AT LEAST 70 OERSTEDS.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-04-07 | 1967-10-07 | 1968-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-04-07 | 1971-10-07 | 1972-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-04-07 | 1975-10-07 | 1976-04-07 | $7700.00 | Window Closed / Lapsed |