US4926097A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ballast circuit for a fluoroescent lamp
Assignee: Q Technology Inc
•
Filing: 1988-03-28
•
Granted: 1990-05-15
•
Expires: 2008-03-28
Abstract
Abstract A ballast circuit for a fluorescent light bulb of the type having an elongated envelope with an electrode at each end. The ballast circuit includes a square wave generator which generates a square wave in excess of 10,000 hertz. The output from the square wave generator is used to modulate a voltage from a power source having a voltage in the range of 400-800 volts so that the modulated voltage has a frequency equal to the square wave frequency. The resulting modulated voltage is then electrically connected to the electrodes of the fluorescent lamp which illuminates the lamp.
Inventors
- 👤 Kim C. Taek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:58
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/282; H05B41/36; H05B41/38; H05B41/39; H05B41/392; H05B41/3921; H05B41/3925; Y; Y02; Y02B; Y02B20/00; Y10; Y10S; Y10S315/00; Y10S315/02; Y10S315/04; Y10S315/05
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
153 words
A ballast circuit for a fluorescent lamp, said lamp comprising an elongated envelope with an electrode at each end, said circuit comprising: means for generating a high frequency square wave in excess of 10,000 Hertz, means for modulating an electrical power source having a voltage in the range of 400-800 volts by said square waver so that the modulated voltage has a frequency at which the voltage polarity inverts equal to said square wave frequency, means for electrically connecting said modulated voltage to the lamp electrodes, and means for dimming said lamp, wherein said dimming means comprises means for varying said square wave frequency, wherein said square wave generating means comprises a fixed frequency oscillator, and wherein said dimming means comprises a variable frequency oscillator responsive to an input signal, means for varying the input signal, and means responsive to an output from the variable frequency oscillator for disabling said fixed frequency oscillator.
Claim 2
Dependent Claim
153 words
A ballast circuit for a fluorescent lamp, said lamp comprising an elongated envelope with an electrode at each end, said circuit comprising: means for generating a high frequency square wave in excess of 10,000 Hertz, means for modulating an electrical power source having a voltage in the range of 400-800 volts by said square waver so that the modulated voltage has a frequency at which the voltage polarity inverts equal to said square wave frequency, means for electrically connecting said modulated voltage to the lamp electrodes, and means for dimming said lamp, wherein said dimming means comprises means for varying said square wave frequency, wherein said square wave generating means comprises a fixed frequency oscillator, and wherein said dimming means comprises a variable frequency oscillator responsive to an input signal, means for varying the input signal, and means responsive to an output from the variable frequency oscillator for disabling said fixed frequency oscillator.
Claim 3
Dependent Claim
19 words
The invention as defined in claim 1 wherein said square wave frequency is in the range of 10-150 kilohertz.
Claim 4
Dependent Claim
17 words
The invention as defined in claim 1 wherein said variable frequency oscillator is a frequency controlled oscillator.
Claim 5
Dependent Claim
18 words
The invention as defined in claim 3 wherein said means for varying the input signal comprises a rheostat.
Claim 6
Dependent Claim
59 words
The invention as defined in claim 1 and comprising means for measuring the frequency of the high frequency square wave generated by the square wave generator means and for generating an output signal when the frequency exceeds a predetermined frequency, and means responsive to said output signal for disabling said square wave generator means for a predetermined time period.
Claim 7
Dependent Claim
139 words
A ballast circuit for a flourescent lamp, said lamp comprising an elongated envelope with an electrode at each end, said circuit comprising: means for generating a high frequency square wave in excess of 10,000 Hertz, means for modulating a voltage from electrical power source having a voltage in the range of 400-800 volts by said square wave so that the modulated voltage has a frequency at which the voltage polarity inverts equal to said square wave frequency, means for electrically connecting said modulated AC voltage to the lamp electrodes, means for measuring the frequency of the high frequency square wave generated by the square wave generator means and for generating an output signal when the frequency exceeds a predetermined frequency, and means responsive to said output signal for disabling said square wave generator means for a predetermined time period.
Claim 8
Dependent Claim
139 words
A ballast circuit for a flourescent lamp, said lamp comprising an elongated envelope with an electrode at each end, said circuit comprising: means for generating a high frequency square wave in excess of 10,000 Hertz, means for modulating a voltage from electrical power source having a voltage in the range of 400-800 volts by said square wave so that the modulated voltage has a frequency at which the voltage polarity inverts equal to said square wave frequency, means for electrically connecting said modulated AC voltage to the lamp electrodes, means for measuring the frequency of the high frequency square wave generated by the square wave generator means and for generating an output signal when the frequency exceeds a predetermined frequency, and means responsive to said output signal for disabling said square wave generator means for a predetermined time period.
Claim 9
Dependent Claim
19 words
The invention as defined in claim 6 wherein said square wave frequency is in the range of 10-150 kilohertz.
Claim 10
Dependent Claim
14 words
The invention as defined in claim 6 and comprising means for dimming said lamp.
Claim 11
Dependent Claim
19 words
The invention as defined in claim 8 wherein said dimming means comprises means for varying said square wave frequency.
Claim 12
Dependent Claim
66 words
The invention as defined in claim 9 wherein said square wave generating means comprises a fixed frequency oscillator, and wherein said dimming means comprises a variable frequency oscillator responsive to an input signal, means for varying the input signal, and means responsive to an output from the variable frequency oscillator for disabling said fixed frequency oscillator, wherein said variable frequency oscillator is a frequency controlled oscillator.
Claim 13
Dependent Claim
18 words
The invention as defined in claim 10 wherein said means for varying the input signal comprises a rheostat.
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) | 1993-05-14 | 1993-11-13 | 1994-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-14 | 1997-11-13 | 1998-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-14 | 2001-11-13 | 2002-05-15 | $7700.00 | Window Closed / Lapsed |