US3155759A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High temperature furnace
Assignee: Individual
•
Filing: 1962-07-03
•
Granted: 1964-11-03
•
Expires: 1982-07-03
Abstract
No abstract record available.
Inventors
- 👤 Leslie H Marshall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:25
CPC Classifications
F; F27; F27D; F27D11/00; F27D11/02; H; H05; H05B; H05B3/00; H05B3/02; H05B3/06; H05B3/10; H05B3/12; H05B3/14; H05B3/141
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
94 words
AN ELECTRIC HEATING UNIT COMPRISING AN ELONGATED ZIRCONIA TUBE OF WHICH THE INNER AND OUTER PERIPHERAL WALLS ARE COAXIAL AND CIRCULAR AT EACH CROSS SECTION, SAID TUBE HAVING END PORTIONS AND A HEATING PORTION OF REDUCED CROSS SECTIONAL AREA INTERMEDIATE THE END PORTIONS, EACH END PORTION HAVING AN OUTER AND WALL OF WHICH THE OUTER FACE IS SUBSTANTIALLY PLANAR AND SYMMETRICAL WITH RESPECT TO THE TUBE AXIS, THIN SHEETS OF PLATINUM-RHODIUM ALLOY INTIMATELY BONDED, BY CURRENT CONDUCTING CEMENTITIOUS MATERIAL, IN FACE-TO-FACE JUXTAPOSITION TO THE OUTER FACES OF EACH END PORTIONS, RESPECTIVELY, CONTACT AREAS OF
Claim 2
Dependent Claim
94 words
AN ELECTRIC HEATING UNIT COMPRISING AN ELONGATED ZIRCONIA TUBE OF WHICH THE INNER AND OUTER PERIPHERAL WALLS ARE COAXIAL AND CIRCULAR AT EACH CROSS SECTION, SAID TUBE HAVING END PORTIONS AND A HEATING PORTION OF REDUCED CROSS SECTIONAL AREA INTERMEDIATE THE END PORTIONS, EACH END PORTION HAVING AN OUTER AND WALL OF WHICH THE OUTER FACE IS SUBSTANTIALLY PLANAR AND SYMMETRICAL WITH RESPECT TO THE TUBE AXIS, THIN SHEETS OF PLATINUM-RHODIUM ALLOY INTIMATELY BONDED, BY CURRENT CONDUCTING CEMENTITIOUS MATERIAL, IN FACE-TO-FACE JUXTAPOSITION TO THE OUTER FACES OF EACH END PORTIONS, RESPECTIVELY, CONTACT AREAS OF
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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) | 1967-11-03 | 1968-05-04 | 1968-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-11-03 | 1972-05-04 | 1972-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-11-03 | 1976-05-04 | 1976-11-03 | $7700.00 | Window Closed / Lapsed |