Patent US3520043A successfully refreshed from Google Patents.
US3520043A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-regulating heating elements
Assignee: Johnson Matthey PLC
•
Filing: 1967-06-16
•
Granted: 1970-07-14
•
Expires: 1987-06-16
Abstract
No abstract record available.
Inventors
- 👤 Alan S Darling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:45
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/62; H01; H01B; H01B1/00; H01B1/02; H01C; H01C1/00; H01C1/14; H01C1/1406; H01C7/00; H01C7/02; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/925; Y10S428/9265; Y10S428/931; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12778; Y10T428/12861; Y10T428/12931; Y10T428/12986
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1180614A
Cited
US1190412A
Cited
US1706130A
Cited
US2188399A
Cited
US2319364A
Cited
US2375154A
Cited
US2412977A
Cited
US2816200A
Cited
US3343928A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-13 | 1974-01-12 | 1974-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-13 | 1978-01-12 | 1978-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-13 | 1982-01-12 | 1982-07-14 | $7700.00 | Window Closed / Lapsed |