US3700857A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical resistance heater
Assignee: AT&T Inc
•
Filing: 1971-04-14
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Granted: 1972-10-24
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Expires: 1991-04-14
Abstract
Abstract A resistance heater comprising a sintered mass of refractory particles, each particle comprising an insulating core coated with a thin film of an electrically conducting material, is obtained by a processing sequence involving coating the particles of interest, compacting the coated particles to form a pellet and sintering the pellet. Devices produced in accordance with the described technique manifest enhanced reliability and uniformity as compared with prior art heaters, and permit a new degree of freedom in the design of heating elements.
Inventors
- 👤 Raymond G Brandes
- 👤 Charles M Pleass
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:36
CPC Classifications
H; H05; H05B; H05B3/00; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
23 words
Device in accordance with claim 1 wherein said particles have a particle size ranging from 80 mesh to Fischer sub-sieve size average 7.0.
References Cited (Backward Citations)
US2717946A
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US2767289A
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US3031344A
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US3052573A
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US3238355A
Cited
US3337365A
Cited
US3404034A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |