US3863102A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent lamp dimming circuit employing an improved auxiliary circuit
Assignee: General Electric Co
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Filing: 1973-04-06
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Granted: 1975-01-28
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Expires: 1993-04-06
Abstract
Abstract An adjustable dimming circuit is provided to control light output levels of a fluorescent lamp. The dimming circuit comprises an intensity selector circuit controlling an auxiliary circuit, and a ballast circuit which is controlled by the auxiliary circuit. The intensity selector circuit provides timing pulses to control the auxiliary circuit. The auxiliary circuit comprises a control switch and a power switch. The control switch is gated on by the intensity selector circuit and controls the operation of the power switch by providing gate current for the power switch after the control switch comes on until zero crossover current in the control switch. The ballast circuit is used to limit current through the fluorescent lamp and to provide starting pulses for the lamp. The power switch in the auxiliary circuit controls the timing of the application of the starting pulses applied to the lamp, and also provides a current path during the operation of the lamp.
Inventors
- 👤 Rollie R Herzog
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:09
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/02; H02M5/04; H02M5/22; H02M5/25; H02M5/257; H02M5/2573; H05; H05B; H05B41/00; H05B41/14; H05B41/36; H05B41/38; H05B41/39; H05B41/392; H05B41/3921; H05B41/3924; Y; Y10; Y10S; Y10S315/00; Y10S315/04
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
143 words
A gaseous discharge lamp dimming circuit for connection to a source of AC voltage comprising: a bilateral current conducting control switch having a control electrode; means for connecting said control switch to the source of AC voltage; means including a timing means, for applying a signal to said control electrode to render said control switch conductive, said control switch conducting current thereafter until the control switch current goes through zero crossover; a bilateral current conducting power switch having a control electrode; said control switch being connected to said control electrode of said power switch for continuously gating said power switch during conduction of said control switch so that said power switch remains on even if the current through said power switch is below the normal power switch holding current level; a ballast circuit connected to said power switch for limiting the lamp current.
Claim 2
Dependent Claim
143 words
A gaseous discharge lamp dimming circuit for connection to a source of AC voltage comprising: a bilateral current conducting control switch having a control electrode; means for connecting said control switch to the source of AC voltage; means including a timing means, for applying a signal to said control electrode to render said control switch conductive, said control switch conducting current thereafter until the control switch current goes through zero crossover; a bilateral current conducting power switch having a control electrode; said control switch being connected to said control electrode of said power switch for continuously gating said power switch during conduction of said control switch so that said power switch remains on even if the current through said power switch is below the normal power switch holding current level; a ballast circuit connected to said power switch for limiting the lamp current.
Claim 3
Dependent Claim
18 words
The dimming circuit as set forth in claim 1, wherein said power switch includes at least one thyristor.
Claim 4
Dependent Claim
25 words
The dimming circuit as set forth in claim 1, wherein said control switch comprises a full-wave rectifier ridge and a thyristor connected across said bridge.
Claim 5
Dependent Claim
28 words
The dimming circuit as set forth in claim 1, further including an isolation transformer for coupling said control electrode of said control switch means to said timing means.
Claim 6
Dependent Claim
26 words
The dimming circuit as set forth in claim 1, further including a step down transformer for connecting said control switch to the source of A.C. voltage.
Claim 7
Dependent Claim
16 words
The dimming circuit as set forth in claim 1, wherein said power switch is a Triac.
Claim 8
Dependent Claim
115 words
A gaseous discharge lamp dimming circuit comprising: a bilateral current conducting control switch having a control electrode; a step down transformer connected to said control switch and adapted to be connected to a source of A.C. voltage for application of a relatively low voltage to said control switch; means for applying a signal to said control electrode of said control switch, said control switch conducting current thereafter until the control switch current goes through zero crossover; a bilateral current conducting power switch having a control electrode; said control switch being connected to said control electrode of said power switch for providing continuous gate current for said power switch during the conduction of said control switch.
Claim 9
Dependent Claim
115 words
A gaseous discharge lamp dimming circuit comprising: a bilateral current conducting control switch having a control electrode; a step down transformer connected to said control switch and adapted to be connected to a source of A.C. voltage for application of a relatively low voltage to said control switch; means for applying a signal to said control electrode of said control switch, said control switch conducting current thereafter until the control switch current goes through zero crossover; a bilateral current conducting power switch having a control electrode; said control switch being connected to said control electrode of said power switch for providing continuous gate current for said power switch during the conduction of said control switch.
Claim 10
Dependent Claim
18 words
The dimming circuit as set forth in claim 7 wherein said power switch includes at least one thyristor.
Claim 11
Dependent Claim
18 words
The dimming circuit as set forth in claim 8 wherein said at least one thyristor is a Triac.
Claim 12
Dependent Claim
18 words
The dimming circuit as set forth in claim 7 wherein said control switch includes at least one thyristor.
Claim 13
Dependent Claim
25 words
The dimming circuit as set forth in claim 9 wherein said control switch includes a full wave bridge and an SCR connected across said bridge.
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) | 1978-01-27 | 1978-07-29 | 1979-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-27 | 1982-07-29 | 1983-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-27 | 1986-07-29 | 1987-01-28 | $7700.00 | Window Closed / Lapsed |