Patent US4544863A successfully refreshed from Google Patents.
US4544863A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power supply apparatus for fluorescent lamp
Assignee: Individual
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Filing: 1984-03-22
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Granted: 1985-10-01
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Expires: 2004-03-22
Abstract
Abstract A power supply apparatus for a fluorescent lamp comprises an inverter circuit for converting AC line power to a high-frequency drive voltage having a square waveform, this high-frequency drive voltage being applied to a fluorescent lamp through an inductor and a capacitor connected in series to form a series-resonance circuit which provides a ballast impedance after ignition of the fluorescent lamp has been achieved. A sufficiently high voltage to ensure reliable ignition of the fluorescent lamp is ensured by a ringing oscillation which is produced across another capacitor, connected across the lamp, when the fluorescent lamp is in the high-impedance state prior to ignition.
Inventors
- 👤 Ken Hashimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:19
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/282; H05B41/2825; Y; Y10; Y10S; Y10S315/00; Y10S315/07
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
148 words
A power supply apparatus for a fluorescent lamp, comprising: inverter means coupled to a source of AC line power, for converting said AC line power to a high-frequency drive voltage having a substantially square waveform, produced from first and second outputs thereof; an inductor and a first capacitor connected in series between said inverter means and a first filament of said fluorescent lamp, for supplying said high-frequency drive voltage to said fluorescent lamp, with the capacitance of said first capacitor and the inductance of said inductor forming a series resonant circuit whose frequency of resonance is higher than but less than twice the value of the frequency of said high-frequency drive voltage, and; a second capacitor connected between an output terminal of said inductor and a second filament of said fluorescent lamp, with the capacitance value of said second capacitor being lower than that of said first capacitor.
Claim 2
Dependent Claim
148 words
A power supply apparatus for a fluorescent lamp, comprising: inverter means coupled to a source of AC line power, for converting said AC line power to a high-frequency drive voltage having a substantially square waveform, produced from first and second outputs thereof; an inductor and a first capacitor connected in series between said inverter means and a first filament of said fluorescent lamp, for supplying said high-frequency drive voltage to said fluorescent lamp, with the capacitance of said first capacitor and the inductance of said inductor forming a series resonant circuit whose frequency of resonance is higher than but less than twice the value of the frequency of said high-frequency drive voltage, and; a second capacitor connected between an output terminal of said inductor and a second filament of said fluorescent lamp, with the capacitance value of said second capacitor being lower than that of said first capacitor.
Claim 3
Dependent Claim
55 words
A power supply apparatus for a fluorescent lamp according to claim 1, in which the capacitance C1 of said first capacitor, the inductance L of said inductor and the frequency F of said high-frequency drive voltage satisfy the following relationship: 1.2F<1/2π√LC1<2F; and, the capacitance value C2 of said second capacitor satisfies the following relationship: 3F<1/2π√LC2
Claim 4
Dependent Claim
102 words
A power supply apparatus for a fluorescent lamp according to claim 1, in which said series-connected inductor and first capacitor are connected between said first output of said inverter circuit means and a first terminal of said first filament of said fluorescent lamp and said second output of said inverter circuit means is connected to a first terminal of said second filament of said fluorescent lamp, and further comprising: a choke coil connected between said first terminals of said first and second filaments; and a two-terminal thyristor and a diode connected in series between second terminals of said first and second filaments.
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) | 1988-09-30 | 1989-04-01 | 1989-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-30 | 1993-04-01 | 1993-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-30 | 1997-04-01 | 1997-10-01 | $7700.00 | Window Closed / Lapsed |