US4001637A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lamp ballast
Assignee: Lutron Electronics Co Inc
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Filing: 1975-06-12
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Granted: 1977-01-04
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Expires: 1995-06-12
Abstract
Abstract A ballast circuit for coupling a lamp to an AC power source and having in series between the source and lamp a non-dissipative current limiting capacitor feeding a rectifier, the output of the rectifier being connected to a smoothing filter. The ballast lends itself particularly to use in connection with a dimmer control, and permits the use of a secondary path or bypass around the dimmer control through another capacitor feeding a rectifier formed as a diode bridge, thereby providing a minimum current level path to the lamp.
Inventors
- 👤 George W. Gray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:07
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/36; H05B41/38; H05B41/39; H05B41/392; Y; Y10; Y10S; Y10S315/00; Y10S315/07
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
69 words
For use in a circuit for coupling an electrical vapor lamp to a cyclic electrical power source, a ballast comprising in series: first substantially non-inductive, non-dissipative, capacitive, current limiting means having an input couplable to said source; rectifying means connected to the output of said current limiting means; and filter means having an input connected to the output of said rectifying means, and an output connectable to said lamp.
Claim 2
Dependent Claim
69 words
For use in a circuit for coupling an electrical vapor lamp to a cyclic electrical power source, a ballast comprising in series: first substantially non-inductive, non-dissipative, capacitive, current limiting means having an input couplable to said source; rectifying means connected to the output of said current limiting means; and filter means having an input connected to the output of said rectifying means, and an output connectable to said lamp.
Claim 3
Dependent Claim
16 words
A circuit as defined in claim 1 wherein said rectifying means is a full-wave diode bridge.
Claim 4
Dependent Claim
15 words
A circuit as defined in claim 1 wherein said filter means is a low-pass filter.
Claim 5
Dependent Claim
22 words
A circuit as defined in claim 1 including an input low-pass filter for coupling said first current limiting means to said source.
Claim 6
Dependent Claim
18 words
A circuit as defined in claim 1 including dimming control means for controlling input current to said ballast.
Claim 7
Dependent Claim
23 words
A circuit as defined in claim 5 wherein said dimming control means is connected to the input of said first current limiting means.
Claim 8
Dependent Claim
37 words
A circuit as defined in claim 6 wherein said first current limiting means comprises a plurality of non-dissipative elements, and said dimming control means comprises means for selectively coupling various of said elements to said power source.
Claim 9
Dependent Claim
43 words
A circuit as defined in claim 6 wherein said dimming control means comprises bidirectional controllable current conductive means for regulating current flow between said power source and said ballast in a first path, and means for controlling conduction through said current conductive device.
Claim 10
Dependent Claim
26 words
A circuit as defined in claim 8 wherein said controllable current conductive means comprises a semiconductor device and said means for controlling comprises phase control means.
Claim 11
Dependent Claim
14 words
A circuit as defined in claim 9 wherein said semiconductor device is a triac.
Claim 12
Dependent Claim
33 words
A circuit as defined in claim 8 including a second current conductive path between said power source and said ballast and second current limiting means for limiting current flow in said second path.
Claim 13
Dependent Claim
15 words
A circuit as defined in claim 11 wherein said second current limiting means is non-dissipative.
Claim 14
Dependent Claim
16 words
A circuit as defined in claim 11 wherein said second current limiting means is a capacitor.
Claim 15
Dependent Claim
51 words
A circuit as defined in claim 11 wherein said rectifying means comprises a full-wave flow diode bridge, said first path being connected to said bridge through said first current limiting means, said second path being connected to said bridge through a pair of unidirectional current conductive elements 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) | 1980-01-04 | 1980-07-05 | 1981-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-04 | 1984-07-05 | 1985-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-04 | 1988-07-05 | 1989-01-04 | $7700.00 | Window Closed / Lapsed |