US3988633A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent lamp with envelope grooves
Assignee: Duro Test Corp
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Filing: 1975-01-30
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Granted: 1976-10-26
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Expires: 1995-01-30
Abstract
Abstract A low pressure discharge lamp, particularly a fluorescent lamp, having a plurality of separate and continuous grooves along its length each of which is formed for 360° around the envelope. The groove configuration maintains a generally arcuate cross-section of varying radius to thereby alter the wall recombination rate of the plasma ions with the phosphor. In the embodiments where the cross-section of the envelope as deformed by the groove is non-circular, the invention also acts to increase the plasma arc stream length thereby changing the electrical and luminous properties of the lamp. A method and apparatus for making the grooves using a plurality of heat sources is also described.
Inventors
- 👤 Joel Shurgan
- 👤 Donald P. Northrop
- 👤 Gordon D. Coplein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:36
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/24; H01J9/245; H01J9/247; C; C03; C03B; C03B23/00; C03B23/04; C03B23/051; H01J61/00; H01J61/02; H01J61/30; H01J61/33; Y; Y02; Y02P; Y02P40/00; Y02P40/50; Y02P40/57
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
103 words
A fluorescent lamp comprising an elongated cylindrical envelope of vitreous material, cathode means at each end of the envelope, a phosphor on the inner wall of said envelope and means within said envelope for producing an arc stream discharge when a voltage is applied across said cathodes, said cylindrical envelope being formed with a plurality of depressed grooves to interact with the arc stream discharge, each of said grooves extending around a major portion of the cylindrical envelope surface and being separate and independent of each other, the areas of the envelope without the grooves defining an overall cylindrical shape for the envelope.
Claim 2
Dependent Claim
103 words
A fluorescent lamp comprising an elongated cylindrical envelope of vitreous material, cathode means at each end of the envelope, a phosphor on the inner wall of said envelope and means within said envelope for producing an arc stream discharge when a voltage is applied across said cathodes, said cylindrical envelope being formed with a plurality of depressed grooves to interact with the arc stream discharge, each of said grooves extending around a major portion of the cylindrical envelope surface and being separate and independent of each other, the areas of the envelope without the grooves defining an overall cylindrical shape for the envelope.
Claim 3
Dependent Claim
23 words
A fluorescent lamp as in claim 1 wherein each said groove extends for 360° around the envelope and starts and finishes on itself.
Claim 4
Dependent Claim
20 words
A fluorescent lamp as in claim 1 wherein each said groove is uniform in depth and shape throughout its extent.
Claim 5
Dependent Claim
19 words
A fluorescent lamp as in claim 1 wherein said grooves extend radially of the longitudinal axis of the envelope.
Claim 6
Dependent Claim
23 words
A fluorescent lamp as in claim 1 wherein said grooves lie at an angle with respect to the longitudinal axis of the envelope.
Claim 7
Dependent Claim
33 words
A fluorescent lamp as in claim 5 wherein said grooves lie at an angle in the range of between about 30° to about 90° with respect to the longitudinal axis of the envelope.
Claim 8
Dependent Claim
27 words
A fluorescent lamp as in claim 5 wherein adjacent grooves are spaced from each other along the length of the envelope and do not overlie each other.
Claim 9
Dependent Claim
20 words
A fluorescent lamp as in claim 7 wherein adjacent grooves are each separated by an undeformed section of the envelope.
Claim 10
Dependent Claim
16 words
A fluorescent lamp as in claim 5 wherein adjacent grooves are spaced to overlie each other.
Claim 11
Dependent Claim
12 words
A fluorescent lamp as in claim 5 wherein each groove is chevron-shaped.
References Cited (Backward Citations)
GB826604A
Cited
US3129085A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-26 | 1980-04-26 | 1980-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-26 | 1984-04-26 | 1984-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-26 | 1988-04-26 | 1988-10-26 | $7700.00 | Window Closed / Lapsed |