US2725439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic coupling device
Assignee: Ronald Trist and Co Ltd
•
Filing: 1951-06-29
•
Granted: 1955-11-29
•
Expires: 1971-06-29
Abstract
No abstract record available.
Inventors
- 👤 Newboult Henry Grattan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:05
CPC Classifications
H; H01; H01H; H01H36/00; H01H36/02; F; F22; F22D; F22D5/00; F22D5/08; G; G01; G01F; G01F23/00; G01F23/30; G01F23/32; G01F23/38
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US246718A
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US2012153A
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GB476114A
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US2204161A
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GB553168A
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US2371511A
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US2520935A
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US2475684A
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US2522815A
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US2577165A
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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) | 1958-11-28 | 1959-05-30 | 1959-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-11-28 | 1963-05-30 | 1963-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-11-28 | 1967-05-30 | 1967-11-29 | $7700.00 | Window Closed / Lapsed |