US3757159A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sodium vapor lamp having improved starting means
Assignee: GTE Sylvania Inc
•
Filing: 1972-07-17
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Granted: 1973-09-04
•
Expires: 1992-07-17
Abstract
Abstract The arc tube of a sodium vapor arc discharge lamp has an external electrical heater in heat transfer relationship therewith. The heater comprises coiled refractory metal wire and is inserted in a ceramic sleeve that is parallel and adjacent to the arc tube.
Inventors
- 👤 J Gutta
- 👤 F Paget
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:42
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/54
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
12 words
The lamp of claim 1 wherein said heater comprises a coiled coil.
Claim 2
Dependent Claim
13 words
The lamp of claim 1 wherein said ceramic sleeve is made of alumina.
Claim 3
Dependent Claim
25 words
The lamp of claim 1 wherein the diameter of said ceramic sleeve is less than about 40 percent of the diameter of said arc tube.
Claim 4
Dependent Claim
19 words
The lamp of claim 1 wherein said switch is closed at room temperature and open at normal lamp operation.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |