US3139518A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heating element
Assignee: Northwest Industries Ltd
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Filing: 1963-01-14
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Granted: 1964-06-30
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Expires: 1983-01-14
Abstract
No abstract record available.
Inventors
- 👤 Gardener Reginald Harry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:09
CPC Classifications
H; H05; H05B; H05B3/00; H05B3/40; B; B29; B29C; B29C45/00; B29C45/17; B29C45/72; B29C45/74
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
172 words
A HEATING ELEMENT COMPRISING: A TUBE OF HIGH HEAT CONDUCTIVELY; A FIRST THIN SHEET OF A NON-ELECTRICALLY CONDUCTING, HIGH HEAT CONDUCTING MATERIAL ENVELOPING SAID TUBE; HEATING COILS WOUND AROUND SAID THIN SHEET IN CONTO A DIFFERENT TEMPERATURE THAN THE OTHER END OF SAID TUBE; A SECOND THIN SHEET OF A NON-ELECTRICALLY CONDUCT NG HIGH HEAT CONDUCTING MATERIAL ENVELOPING SAID HEATING ELEMENTS, A SLEEVE OF NON-ELECTRICALLY CONDUCTING HIGH HEAT RESISTING MATERIAL ENVELOPING SAID SECOND SHEET; A THIRD SHEET OF A HIGH HEAT CONDUCTIVE MATERIAL HAVING A HIGH HEAT REFLECTIVE EXTERIOR SURFACE ENVELOPING A PORTION OF SAID SLEEVE AT THE END OF THE TUBE WHICH MAY BE HEATED TO THE LOWER TEMPERATURE; AND A FOURTH SHEET OF A HIGH HEAT CONDUCTIVE MATERIAL HAVING A HIGH HEAT REFLECTIVE SURFACE ENVELOPING THE REMAINING PORTION OF THE SLEEVE AT THE END OF THE TUBE WHICH MAY BE HEATED TO THE HIGHER TEMPERATURE, A SLECTED PORTION OF THE FOURTH SHEET BUTTING A TERMINAL EDGE OF THE THIRD SHEET AND FLARING OUTWARDLY FROM A PORTION OF THE THIRD SHEET.
Claim 2
Dependent Claim
172 words
A HEATING ELEMENT COMPRISING: A TUBE OF HIGH HEAT CONDUCTIVELY; A FIRST THIN SHEET OF A NON-ELECTRICALLY CONDUCTING, HIGH HEAT CONDUCTING MATERIAL ENVELOPING SAID TUBE; HEATING COILS WOUND AROUND SAID THIN SHEET IN CONTO A DIFFERENT TEMPERATURE THAN THE OTHER END OF SAID TUBE; A SECOND THIN SHEET OF A NON-ELECTRICALLY CONDUCT NG HIGH HEAT CONDUCTING MATERIAL ENVELOPING SAID HEATING ELEMENTS, A SLEEVE OF NON-ELECTRICALLY CONDUCTING HIGH HEAT RESISTING MATERIAL ENVELOPING SAID SECOND SHEET; A THIRD SHEET OF A HIGH HEAT CONDUCTIVE MATERIAL HAVING A HIGH HEAT REFLECTIVE EXTERIOR SURFACE ENVELOPING A PORTION OF SAID SLEEVE AT THE END OF THE TUBE WHICH MAY BE HEATED TO THE LOWER TEMPERATURE; AND A FOURTH SHEET OF A HIGH HEAT CONDUCTIVE MATERIAL HAVING A HIGH HEAT REFLECTIVE SURFACE ENVELOPING THE REMAINING PORTION OF THE SLEEVE AT THE END OF THE TUBE WHICH MAY BE HEATED TO THE HIGHER TEMPERATURE, A SLECTED PORTION OF THE FOURTH SHEET BUTTING A TERMINAL EDGE OF THE THIRD SHEET AND FLARING OUTWARDLY FROM A PORTION OF THE THIRD SHEET.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-06-30 | 1967-12-30 | 1968-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-06-30 | 1971-12-30 | 1972-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-06-30 | 1975-12-30 | 1976-06-30 | $7700.00 | Window Closed / Lapsed |