US3767970A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Turn on/turn off circuit for the direct current operation of gaseous discharge lamps
Assignee: General Electric Co
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Filing: 1972-11-01
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Granted: 1973-10-23
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Expires: 1992-11-01
Abstract
Abstract There is provided a circuit for solid-state starting and ballasting gaseous discharge lamps operating on direct current. The circuit provides a means of positive turn off and turn on of gaseous discharge lamps. A direct current source is connected in series with a starting pulse transformer, a gaseous discharge lamp and a constant current ballast transistor. A resistor is connected across the lamp to shunt the ballast transistor offstate leakage current away from the lamp and a second transistor is connected to the base of the ballast transistor to provide a shunt path for the off-state leakage current away from the baseemitter junction of the ballast transistor. The starting circuit for the lamp, which comprises an SCR connected in series with a pulse transformer primary winding and a capacitor, is separated from the transistor ballast. A charging resistor is connected between the direct current source and the starting means, the value being large enough to conduct current below the holding current of the SCR so that it will commutate when gate drive is removed. The gate terminal of the SCR and the base of the ballast transistor are connected to a common control signal input. A second capacitor is connected to the direct current source and to the collector of the ballast transistor to bypass starting voltage spikes from the ballast transistor and to aid in starting the lamp.
Inventors
- 👤 J Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:38
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/36; H05B41/38; H05B41/39; H05B41/392; Y; Y10; Y10S; Y10S315/00; Y10S315/05; Y10S315/07
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
88 words
A circuit for operating at least one gaseous lamp comprising: input means for connecting the circuit to a DC source; starting means connected to said input means and to the lamp; solid-state ballast connected to the lamp; first resistance means connected to at least one side of the lamp and to said solid-state ballast for shunting leakage current drawn by said solid-state ballast away from the lamp, said first resistance means of a size such that its voltage drop is below the glow sustaining voltage of the lamp.
Claim 2
Dependent Claim
88 words
A circuit for operating at least one gaseous lamp comprising: input means for connecting the circuit to a DC source; starting means connected to said input means and to the lamp; solid-state ballast connected to the lamp; first resistance means connected to at least one side of the lamp and to said solid-state ballast for shunting leakage current drawn by said solid-state ballast away from the lamp, said first resistance means of a size such that its voltage drop is below the glow sustaining voltage of the lamp.
Claim 3
Dependent Claim
58 words
A circuit as set forth in claim 1 wherein said solid-state ballast includes a first transistor having a base, emitter, and a collector; and further including shunt means connected between said base and said emitter of said first transistor for shunting leakage current through said collector and said base and away from said emitter of said first transistor.
Claim 4
Dependent Claim
39 words
A circuit as set forth in claim 2 wherein said shunt means includes a second transistor having a base, an emitter, and a collector; said collector of said second transistor being connected to said base of said first transistor.
Claim 5
Dependent Claim
19 words
A circuit as set forth in claim 1 wherein said starting means is substantially isolated from said solid-state ballast.
Claim 6
Dependent Claim
69 words
A circuit as set forth in claim 4 wherein said starting means includes: a capacitance, a thyristor, and a primary winding of a pulse transformer connected in a series loop; a second resistance means connected to the junction of said capacitance and said primary winding and to said input means, and a secondary winding of said pulse transformer connected to the lamp and closely coupled with said primary winding.
Claim 7
Dependent Claim
37 words
A circuit as set forth in claim 5 wherein: the value of said second resistance means is such that the level of current through said resistance means is below the minimum holding current level of said thyristor.
Claim 8
Dependent Claim
23 words
A circuit as set forth in claim 5 wherein the gate said thyristor and solid-state ballast are connected to a common control terminal.
Claim 9
Dependent Claim
44 words
A circuit as set forth in claim 1 further including: a capacitance connected between said input means and said solid-state ballast for providing an initial current for said solid-state ballast and further for providing a high frequency shunt path away from said solid-state ballast.
Claim 10
Dependent Claim
17 words
A circuit as set forth in claim 1 further including regulation means connected to said solid-state ballast.
Claim 11
Dependent Claim
46 words
A circuit as set forth in claim 9 wherein: said solid-state ballast includes a transistor connected to the lamp; said regulation means includes a Zener diode and resistance connected to said transistor in a feedback arrangement; and means for connecting said transistor to a control signal.
Claim 12
Dependent Claim
34 words
A circuit as set forth in claim 1 wherein said starting means includes a transformer secondary winding, one side of said first resistance means being connected between saiD secondary winding and said input means.
Claim 13
Dependent Claim
18 words
A circuit as set forth in claim 1 wherein said first resistance means is connected across the lamp.
Claim 14
Dependent Claim
233 words
A circuit for operating at least one gaseous discharge lamp comprising: input means for connecting the circuit to a DC source; pulse starting means including a thyristor having an anode, a cathode, and a gate, a starting capacitor having one side connected to said cathode of said thyristor and ground, a transformer having primary and secondary windings, said primary winding being connected between said anode of said thyristor and the other side of said starting capacitor, said secondary winding being connected between said input means and the lamp, a charging resistor connected between the other side of said starting capacitor and said input means; ballast means including a ballast transistor having a base, an emitter, and a collector, said collector connected to the lamp; regulation means including resistance means connected between said emitter of said ballast transistor and ground, and a Zener diode connected between said base of said ballast transistor and ground; control means connected to said base of said ballast transistor and said gate of said thyristor; shunt resistance connected to said input means and to said collector of said ballast transistor; current initiating capacitor connected between said input means and said collector of said ballast transistor; a shunt transistor having a base, an emitter, and a collector, said collector of said shunt transistor connected to said base of said ballast transistor, said emitter of said shunt transistor connected to ground.
Claim 15
Dependent Claim
233 words
A circuit for operating at least one gaseous discharge lamp comprising: input means for connecting the circuit to a DC source; pulse starting means including a thyristor having an anode, a cathode, and a gate, a starting capacitor having one side connected to said cathode of said thyristor and ground, a transformer having primary and secondary windings, said primary winding being connected between said anode of said thyristor and the other side of said starting capacitor, said secondary winding being connected between said input means and the lamp, a charging resistor connected between the other side of said starting capacitor and said input means; ballast means including a ballast transistor having a base, an emitter, and a collector, said collector connected to the lamp; regulation means including resistance means connected between said emitter of said ballast transistor and ground, and a Zener diode connected between said base of said ballast transistor and ground; control means connected to said base of said ballast transistor and said gate of said thyristor; shunt resistance connected to said input means and to said collector of said ballast transistor; current initiating capacitor connected between said input means and said collector of said ballast transistor; a shunt transistor having a base, an emitter, and a collector, said collector of said shunt transistor connected to said base of said ballast transistor, said emitter of said shunt transistor connected to ground.
References Cited (Backward Citations)
US3066241A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-22 | 1977-04-23 | 1977-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-22 | 1981-04-23 | 1981-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-22 | 1985-04-23 | 1985-10-23 | $7700.00 | Window Closed / Lapsed |