US4039897A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for controlling power applied to a gas discharge lamp
Assignee: Individual
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Filing: 1976-03-08
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Granted: 1977-08-02
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Expires: 1996-03-08
Abstract
Abstract A system for controlling power applied to a gas discharge lamp by an AC source, wherein the power dissipated in the lamp during a half cycle is sensed by a measuring circuit. The measuring circuit provides output signals proportional to the current through and voltage across the lamp during its conduction. The measuring circuit output signals are multiplied and the difference between the resultant multiplier signal and a reference signal is time integrated and fed to a pulse width modulator. The pulse width modulator provides a pulse to a pulse transformer to trigger an SCR in series with the lamp at some point in the next half cycle, the point at which the SCR is triggered being determined by the power dissipated in the lamp in the previous half cycle. In another embodiment the SCR is replaced by a transistor and the pulse width modulator shuts off the transistor after the lamp has dissipated the desired amount of power in a given half cycle.
Inventors
- 👤 James E. Dragoset
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:30
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/36; H05B41/38; H05B41/39; H05B41/392; Y; Y10; Y10S; Y10S315/00; Y10S315/05; Y10S315/07
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
170 words
A system for controlling power dissipated in a gas discharge lamp powered by an AC supply, comprising a. a semi-conductor adapted to be rendered conductive by an actuating pulse, said semi-conductor and said lamp being connected in series across the AC power supply, b. a measuring network connected to the lamp for measuring voltage across and current through the lamp in a given half cycle of the AC power supply and for providing output signals proportional to said voltage and current, c. means connected to the measuring network for multiplying said output signals and providing a multiplied signal, d. means connected to the multiplying means for integrating said multiplied signal and providing an integrated output signal, and e. means synchronized with the AC power supply and connected to the integrating means for actuating the semi-conductor to adjust the time interval in a subsequent half cycle during which the lamp is allowed to conduct, said adjustment being made in response to power dissipated in the lamp in said given half cycle.
Claim 2
Independent Claim
170 words
A system for controlling power dissipated in a gas discharge lamp powered by an AC supply, comprising a. a semi-conductor adapted to be rendered conductive by an actuating pulse, said semi-conductor and said lamp being connected in series across the AC power supply, b. a measuring network connected to the lamp for measuring voltage across and current through the lamp in a given half cycle of the AC power supply and for providing output signals proportional to said voltage and current, c. means connected to the measuring network for multiplying said output signals and providing a multiplied signal, d. means connected to the multiplying means for integrating said multiplied signal and providing an integrated output signal, and e. means synchronized with the AC power supply and connected to the integrating means for actuating the semi-conductor to adjust the time interval in a subsequent half cycle during which the lamp is allowed to conduct, said adjustment being made in response to power dissipated in the lamp in said given half cycle.
Claim 3
Dependent Claim
55 words
The system of claim 1 wherein the measuring network includes an impedence connected in series with the lamp and means for amplifying the voltage across the lamp, said multiplying means being connected to receive a voltage signal from the amplifying means and a current signal from a point connected between the lamp and said impedence.
Claim 4
Dependent Claim
36 words
The system of claim 2 wherein the system includes a DC reference source connected as an input to the integrating means, said integrating means integrating the difference between the multiplied signal and said DC reference source.
Claim 5
Dependent Claim
60 words
The system of claim 3 wherein the pulse width modulator comprises an amplifier and means synchronized with the AC power supply for generating a sawtooth signal, said amplifier being connected to amplify the difference between the signal from the integrating means and said sawtooth signal to provide an actuating signal to the semi-conductor, said semi-conductor being a silicon controlled rectifier.
Claim 6
Dependent Claim
52 words
The system of claim 2 wherein the pulse width modulator includes an amplifier and a DC reference source, said amplifier being connected to amplify the difference between the DC reference source and the output signal of the integrating means for providing an actuating signal to the semi-conductor, said semi-conductor being a transistor.
Claim 7
Independent Claim
231 words
A system for controlling power dissipated in a gas discharge lamp powered by an AC power supply, comprising a. a resistor connected in series with the lamp, said resistor being connected between the lamp and ground, b. a first amplifier connected across the lamp for amplifying the voltage across the lamp to provide a voltage signal, c. a multiplier having one input connected to the first amplifier and another input connected to the end of the lamp adjacent to the resistor for providing a multiplied signal, d. a DC reference source, e. a difference integrator connected to integrate the difference between the DC reference source and the multiplied signal and provide an integrated signal, f. a switch connected between the multiplier and the integrator, g. means connected to the switch for turning said switch on and off in timed relationship to the AC power supply, h. means for generating a sawtooth signal, said sawtooth signal being synchronized with the AC power supply, i. a second amplifier connected to compare the sawtooth signal and the integrated signal and produce a positive pulse each time the sawtooth signal becomes positive with respect to the integrated signal, j. means connected to the amplifier for converting said positive pulses to spaced positive signals, and k. a silicon controlled rectifier connected in series with the lamp and adapted to be triggered by said spaced positive pulses.
Claim 8
Independent Claim
231 words
A system for controlling power dissipated in a gas discharge lamp powered by an AC power supply, comprising a. a resistor connected in series with the lamp, said resistor being connected between the lamp and ground, b. a first amplifier connected across the lamp for amplifying the voltage across the lamp to provide a voltage signal, c. a multiplier having one input connected to the first amplifier and another input connected to the end of the lamp adjacent to the resistor for providing a multiplied signal, d. a DC reference source, e. a difference integrator connected to integrate the difference between the DC reference source and the multiplied signal and provide an integrated signal, f. a switch connected between the multiplier and the integrator, g. means connected to the switch for turning said switch on and off in timed relationship to the AC power supply, h. means for generating a sawtooth signal, said sawtooth signal being synchronized with the AC power supply, i. a second amplifier connected to compare the sawtooth signal and the integrated signal and produce a positive pulse each time the sawtooth signal becomes positive with respect to the integrated signal, j. means connected to the amplifier for converting said positive pulses to spaced positive signals, and k. a silicon controlled rectifier connected in series with the lamp and adapted to be triggered by said spaced positive pulses.
Claim 9
Dependent Claim
25 words
The system of claim 5 wherein the switch is a field effect transistor and the means for turning the switch on is a signal generator.
Claim 10
Dependent Claim
20 words
The system of claim 7 wherein a pulse transformer is connected between the second amplifier and the silicon controlled rectifier.
Claim 11
Dependent Claim
59 words
The system of claim 8 wherein a pair of silicon controlled rectifiers are connected in parallel with each other and in series with the lamp, one of said rectifiers being connected to conduct during positive half cycles of the AC power supply and the other said rectifier being connected to conduct during hegative half cycles of said power supply.
Claim 12
Independent Claim
216 words
A system for controlling power dissipated in a gas discharge lamp powered by an AC power supply, comprising a. a resistor connected in series with the lamp, b. a first amplifier connected across the lamp for amplifying the voltage across the lamp to provide a voltage signal, c. a multiplier having one input connected to the first amplifier and another input connected to the end of the lamp adjacent to the resistor for providing a multiplied signal, d. a re-settable integrator connected to receive and integrate the multiplier signal to provide an integrated signal, e. a signal generator synchronized with the AC power supply and connected to the integrator for re-setting said integrator in timed relationship with said AC power supply, f. a DC reference source, g. a second amplifier connected to the DC reference source and the integrator for comparing the integrated signal with said reference source and providing an actuating signal, and h. a pair of transistors connected in parallel with each other and in series with the lamp, one of said transistors being connected to conduct during positive half cycles of the power supply and the other transistor being connected to conduct during negative half cycles of said power supply, said transistors being connected to the second amplifier for receiving said actuating signals.
Claim 13
Independent Claim
216 words
A system for controlling power dissipated in a gas discharge lamp powered by an AC power supply, comprising a. a resistor connected in series with the lamp, b. a first amplifier connected across the lamp for amplifying the voltage across the lamp to provide a voltage signal, c. a multiplier having one input connected to the first amplifier and another input connected to the end of the lamp adjacent to the resistor for providing a multiplied signal, d. a re-settable integrator connected to receive and integrate the multiplier signal to provide an integrated signal, e. a signal generator synchronized with the AC power supply and connected to the integrator for re-setting said integrator in timed relationship with said AC power supply, f. a DC reference source, g. a second amplifier connected to the DC reference source and the integrator for comparing the integrated signal with said reference source and providing an actuating signal, and h. a pair of transistors connected in parallel with each other and in series with the lamp, one of said transistors being connected to conduct during positive half cycles of the power supply and the other transistor being connected to conduct during negative half cycles of said power supply, said transistors being connected to the second amplifier for receiving said actuating signals.
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) | 1980-08-01 | 1981-01-31 | 1981-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-08-01 | 1985-01-31 | 1985-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-08-01 | 1989-01-31 | 1989-08-02 | $7700.00 | Window Closed / Lapsed |