US4525651A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Capacitively ballasted low voltage incandescent lamp
Assignee: General Electric Co
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Filing: 1984-07-16
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Granted: 1985-06-25
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Expires: 2004-07-16
Abstract
Abstract A capacitively ballasted low voltage lamp comprising a main capacitor connected electrically in series with the lamp, across an alternating current source, and one or more auxiliary capacitors that can be connected electrically across the main capacitor by switching means for one or more source waveform cycles. The minimum lamp current is established by the main capacitor, with additional lamp current flowing through one or more auxiliary capacitors during one or more source waveform cycles.
Inventors
- 👤 Frederic F. Ahlgren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:07
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/02; H02M5/04; H02M5/06; H02M5/08; Y; Y10; Y10S; Y10S315/00; Y10S315/04
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
123 words
A ballast circuit means controlling power from an alternating current source to an incandescent lamp, having a filament, at a voltage magnitude that is less than the alternating current source voltage comprising: (a) a first capacitive element electrically serially connected to said lamp which together are across the ballast means input terminals; (b) at least one auxiliary capacitive element; (c) a control means connected across the filament of said lamp generating discrete control signals in response to conditions of the current flowing through the filament; and, (d) switching means responsive to said control signals for selectively and individually electrically connecting each auxiliary capacitive element in parallel across said first capacitive element for one or more complete cycles of the alternating current source waveform.
Claim 2
Dependent Claim
123 words
A ballast circuit means controlling power from an alternating current source to an incandescent lamp, having a filament, at a voltage magnitude that is less than the alternating current source voltage comprising: (a) a first capacitive element electrically serially connected to said lamp which together are across the ballast means input terminals; (b) at least one auxiliary capacitive element; (c) a control means connected across the filament of said lamp generating discrete control signals in response to conditions of the current flowing through the filament; and, (d) switching means responsive to said control signals for selectively and individually electrically connecting each auxiliary capacitive element in parallel across said first capacitive element for one or more complete cycles of the alternating current source waveform.
Claim 3
Dependent Claim
21 words
A ballast means as claimed in claim 1 wherein each auxiliary capacitive element has said switching means electrically in series therewith.
Claim 4
Dependent Claim
21 words
A ballast means as claimed in claim 1 wherein said switching means provides a low resistance, bidirectional current conduction path therethrough.
Claim 5
Dependent Claim
18 words
A ballast means as claimed in claim 3 wherein said switching means are switched independently of each other.
Claim 6
Dependent Claim
210 words
A ballast means controlling power from an alternating current source to an incandescent lamp, having a filament, at a voltage magnitude that is less than the alternating source voltage comprising: (a) a first capacitive element electrically serially connected to said lamp which together are across the ballast means input terminals; (b) at least one auxiliary capacitive element; (c) a control means connected across the filament of said lamp generating a control signal in response to conditions of current flowing through the filament; (d) switching means responsive to said control signal for electrically connecting each auxiliary capacitive element in parallel across said first capacitive element for one or more cycles of the alternating current source waveform; said switching means providing a low resistance, bidirectional current conduction path therethrough, said switching means being switched independent of each other, and; wherein each of said auxiliary capacitive element has values selected so that at the time each auxiliary capacitive element is electrically connected in parallel with said first capacitive element by saiid switching means in response to said control means, the voltage potential across each of said auxiliary capacitive element, which is electrically connected in parallel with said first capacitive element, is approximately the same as the voltage potential across said first capacitive element.
Claim 7
Dependent Claim
210 words
A ballast means controlling power from an alternating current source to an incandescent lamp, having a filament, at a voltage magnitude that is less than the alternating source voltage comprising: (a) a first capacitive element electrically serially connected to said lamp which together are across the ballast means input terminals; (b) at least one auxiliary capacitive element; (c) a control means connected across the filament of said lamp generating a control signal in response to conditions of current flowing through the filament; (d) switching means responsive to said control signal for electrically connecting each auxiliary capacitive element in parallel across said first capacitive element for one or more cycles of the alternating current source waveform; said switching means providing a low resistance, bidirectional current conduction path therethrough, said switching means being switched independent of each other, and; wherein each of said auxiliary capacitive element has values selected so that at the time each auxiliary capacitive element is electrically connected in parallel with said first capacitive element by saiid switching means in response to said control means, the voltage potential across each of said auxiliary capacitive element, which is electrically connected in parallel with said first capacitive element, is approximately the same as the voltage potential across said first capacitive element.
Claim 8
Dependent Claim
28 words
A ballast means as claimed in claim 1 wherein each of said switching means is switched to a conductive and non-conductive state in response to a control signal.
Claim 9
Dependent Claim
61 words
A ballast means as claimed in claim 1 wherein said incandescent lamp is operating at approximately 36 volts, 60 watts; said first capacitive element has a capacitance of approximately 25 microfarads; said at least one or more auxiliary capacitive elements has a total capacitance of approximately 25 microfarads; and said ballast means input voltage is approximately 120 volts at 60 hertz.
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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) | 1988-06-24 | 1988-12-24 | 1989-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-24 | 1992-12-24 | 1993-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-24 | 1996-12-24 | 1997-06-25 | $7700.00 | Window Closed / Lapsed |