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US4145636A Expired / Lapsed US ⏱️ 0.0 years remaining

Fluorescent lamp driving circuit

Assignee: I S ENGR CO Ltd
•
Filing: 1977-08-08
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Granted: 1979-03-20
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Expires: 1997-08-08
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Abstract

Abstract There is disclosed an oscillator circuit for driving a fluorescent lamp, which comprises a power transistor having an emitter electrode connected to one terminal of a D.C. power source and a collector electrode connected to the other terminal of the D.C. power source through a primary winding of a transformer. A first secondary winding of the transformer is connected at its one end to the other terminal of the D.C. power source and at its other end to a base electrode of the transistor through one of a pair of filaments of the fluorescent lamp. A second secondary winding of the transformer is connected at its one end to the one filament of the fluorescent lamp and at its other end to the other filament of the fluorescent lamp to cause discharge in the fluorescent lamp.

Inventors

  • 👤 Shigemitsu Doi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 19:46
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/295; Y; Y10; Y10S; Y10S315/00; Y10S315/05; Y10S315/07

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 131 words
A relaxation oscillator circuit for driving a fluorescent lamp with a D.C. power source comprising a transistor having a first electrode connected to one terminal of the D.C. power source, and a transformer having a primary winding one end of which is connected to the other terminal of the D.C. power source and the other end being connected to a second electrode of said transistor, said transformer having a first secondary winding connected at one end thereof to said other terminal of the D.C. power source and at the other end thereof to a third electrode of said transistor through a resistor and one of a pair of filaments of the fluorescent lamp, said transformer also having a second secondary winding connected across the pair of filaments of the fluorescent lamp.
Claim 2
Dependent Claim 131 words
A relaxation oscillator circuit for driving a fluorescent lamp with a D.C. power source comprising a transistor having a first electrode connected to one terminal of the D.C. power source, and a transformer having a primary winding one end of which is connected to the other terminal of the D.C. power source and the other end being connected to a second electrode of said transistor, said transformer having a first secondary winding connected at one end thereof to said other terminal of the D.C. power source and at the other end thereof to a third electrode of said transistor through a resistor and one of a pair of filaments of the fluorescent lamp, said transformer also having a second secondary winding connected across the pair of filaments of the fluorescent lamp.
Claim 3
Dependent Claim 75 words
A relaxation oscillator circuit as set forth in claim 1 wherein said transistor is a NPN power transistor wherein the emitter electrode thereof comprises said first electrode, the collector electrode thereof comprises said second electrode, and the base electrode thereof comprises said third electrode of said power transistor, and wherein said one terminal of said D.C. power source comprises a negative terminal and said other terminal of said D.C. power source comprises a positive terminal.
Claim 4
Dependent Claim 20 words
A relaxation oscillator circuit as set forth in claim 2 wherein a capacitor is connected in parallel with said resistor.

References Cited (Backward Citations)

US3066241A Cited
US3501674A Cited
US3505562A Cited
US3720861A Cited
US3882354A Cited
US4071807A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-03-19 1982-09-18 1983-03-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-03-19 1986-09-18 1987-03-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-03-19 1990-09-18 1991-03-20 $7700.00 Window Closed / Lapsed

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