US3659138A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alumina-metal sealed lamp apparatus
Assignee: General Electric Co
•
Filing: 1970-11-06
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Granted: 1972-04-25
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Expires: 1990-11-06
Abstract
Abstract Improved seal structure, particularly useful in the fabrication of electric lamps and the like includes a crystalline alumina member and a thin molybdenum member sealed to one another by a substantial mass of interposed sealing glass having a softening point of approximately 1,400* C. to 1,600* C., and forming a concave surface between the sealed members which intersects the respective members at a small angle having a radius of curvature which is large as compared with the thickness dimension of the molybdenum member.
Inventors
- 👤 Peter D Johnson
- 👤 Howard A Poran
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:40
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/36; H01J5/00; H01J5/32; H01J5/40; H01J2893/00; H01J2893/0033; H01J2893/0034; H01J2893/0035
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
24 words
The improvement of claim 1 wherein both of said angles are of less than 10* and said radius is in excess of 0.10 millimeter.
Claim 2
Dependent Claim
13 words
The improvement of claim 1 wherein said sealing glass is calcium magnesium aluminate.
Claim 3
Dependent Claim
14 words
The improvement of claim 3 wherein said envelope wall is a polycrystalline alumina ceramic.
Claim 4
Dependent Claim
23 words
The improvement of claim 1 wherein said molybdenum is an electrode support member and an arc-electrode is affixed to the inwardly-depending end thereof.
References Cited (Backward Citations)
US3588577A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-25 | 1975-10-25 | 1976-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-25 | 1979-10-25 | 1980-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-25 | 1983-10-25 | 1984-04-25 | $7700.00 | Window Closed / Lapsed |