US4285032A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tubular incandescent lamp
Assignee: Toshiba Corp
•
Filing: 1979-07-30
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Granted: 1981-08-18
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Expires: 1999-07-30
Abstract
Abstract A tubular incandescent lamp which comprises an elongate transparent envelope; and a plurality of small lamps linearly arranged and extending lengthwise through the envelope, each of said small lamps containing a helically coiled filament and wherein the difference between the inner diameter of the envelope and the outer diameter of the respective lamps is chosen to be 2 mm or less.
Inventors
- 👤 Kiyokazu Honda
- 👤 Yoshiji Yoshiike
- 👤 Katsuo Muraki
- 👤 Teruyoshi Kawamata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:03
CPC Classifications
H; H01; H01K; H01K7/00; G; G03; G03G; G03G15/00; G03G15/04; G03G15/04036; H01K1/00; H01K1/28; H01K1/34; Y; Y02; Y02B; Y02B20/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
116 words
A tubular incandescent lamp for illuminating an adjacent surface which comprises: an elongate transparent envelope; and a plurality of small lamps linearly arranged and extending lengthwise through the envelope, each of said small lamps containing a helically coiled filament and lead lines for connecting the filament of each lamp to at least one adjacent lamp, said lead lines elongating in use so that said lamps incline in said envelope, and wherein the difference between the inner diameter of the envelope and the outer diameter of the respective small lamps is 2 mm or less to limit the inclination of said lamps and thus to limit variations in intensity of illumination from said lamps onto said surface.
Claim 2
Dependent Claim
116 words
A tubular incandescent lamp for illuminating an adjacent surface which comprises: an elongate transparent envelope; and a plurality of small lamps linearly arranged and extending lengthwise through the envelope, each of said small lamps containing a helically coiled filament and lead lines for connecting the filament of each lamp to at least one adjacent lamp, said lead lines elongating in use so that said lamps incline in said envelope, and wherein the difference between the inner diameter of the envelope and the outer diameter of the respective small lamps is 2 mm or less to limit the inclination of said lamps and thus to limit variations in intensity of illumination from said lamps onto said surface.
Claim 3
Dependent Claim
35 words
The tubular incandescent lamp according to claim 1, wherein a difference between the inner diameter of the envelope and the outer diameter of the respective small lamps is chosen to be 1 to 2 mm.
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) | 1984-08-17 | 1985-02-16 | 1985-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-17 | 1989-02-16 | 1989-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-17 | 1993-02-16 | 1993-08-18 | $7700.00 | Window Closed / Lapsed |