Patent US3393729A successfully refreshed from Google Patents.
US3393729A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat exchange mantle with interchangeable cartridge means
Assignee: AT&T Inc
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Filing: 1966-08-01
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Granted: 1968-07-23
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Expires: 1986-08-01
Abstract
No abstract record available.
Inventors
- 👤 Harold A Sauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:35
CPC Classifications
F; F28; F28D; F28D7/00; F28D7/02; F28D7/026; F28F; F28F21/00; F28F21/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2690327A
Cited
US2721729A
Cited
US2998966A
Cited
US3129459A
Cited
US3074695A
Cited
US3200878A
Cited
US3225821A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-07-23 | 1972-01-22 | 1972-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-07-23 | 1976-01-22 | 1976-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-07-23 | 1980-01-22 | 1980-07-23 | $7700.00 | Window Closed / Lapsed |