US4425530A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time delay lamp ballast circuit
Assignee: General Electric Co
•
Filing: 1981-10-22
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Granted: 1984-01-10
•
Expires: 2001-10-22
Abstract
Abstract A multiple fluorescent lamp ballast circuit of the rapid start type in which heating current is supplied to the lamp cathodes. A time delay switch is connected in series with a starting capacitor across one or more of the lamps, to delay lamp starting until the cathodes are sufficiently heated.
Inventors
- 👤 Edward E. Hammer
- 👤 Eugene Lemmers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:58
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/16; H05B41/18; Y; Y10; Y10S; Y10S315/00; Y10S315/05
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
126 words
A rapid start fluorescent lamp circuit having two or more fluorescent lamps connected in electrical series across a source of operating voltage, means to supply heating current to the lamp cathodes, and a starting capacitor and a time delay switch connected in series across one or more of said lamps, said time delay switch being adapted to close after the cathodes of said lamps have heated to a desired temperature to apply substantially all of the operating voltage across a first one of said lamps to start said first one of said lamps and after starting of said first one of said lamps to allow the application of substantially all of the operating voltage across another of said lamps to start said another of said lamps.
Claim 2
Dependent Claim
126 words
A rapid start fluorescent lamp circuit having two or more fluorescent lamps connected in electrical series across a source of operating voltage, means to supply heating current to the lamp cathodes, and a starting capacitor and a time delay switch connected in series across one or more of said lamps, said time delay switch being adapted to close after the cathodes of said lamps have heated to a desired temperature to apply substantially all of the operating voltage across a first one of said lamps to start said first one of said lamps and after starting of said first one of said lamps to allow the application of substantially all of the operating voltage across another of said lamps to start said another of said lamps.
Claim 3
Dependent Claim
50 words
A circuit as claimed in claim 1, in which said time delay switch comprises a heater resistor connected in the current path of one or more of said cathodes, and a bimetal switch contact means positioned to be heated by said resistor and connected in series with said starting capacitor.
Claim 4
Dependent Claim
17 words
A circuit as claimed in claim 1, in which said time delay switch comprises a glow-starter switch.
Claim 5
Dependent Claim
58 words
A circuit as claimed in claim 1, comprising three or more fluorescent lamps connected in electrical series, said starting capacitor being connected across a first one of said lamps, and an additional starting capacitor connected across two of said lamps including said first lamp, said time delay switch being interposed in series with one of said starting capacitors.
Claim 6
Dependent Claim
22 words
A circuit as claimed in claim 4, in which said time delay switch is interposed in series with said additional starting capacitor.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-09 | 1987-07-11 | 1988-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-09 | 1991-07-11 | 1992-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-09 | 1995-07-11 | 1996-01-10 | $7700.00 | Window Closed / Lapsed |