Patent EP0043112A2 successfully refreshed from Google Patents.
EP0043112A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Discharge lamp operating circuit
Assignee: Osram Sylvania Inc
•
Filing: 1981-06-26
•
Granted: —
•
Expires: 2001-06-26
Abstract
Abstract A lamp operating circuit comprising a DC power source, an inverter including step-up transformer inductance windings and a controlled transistor switch connected across the output of the DC source, and a high frequency oscillator coupled to the transistor switch for operating the same at predetermined intervals. A low wattage HID lamp is connected across the inverter through a ballast capacitor series connected to one terminal of the lamp and a ballast inductance coupled in series with the other lamp terminal. The ballast inductance and ballast capacitor are selected to resonate sinusoidally at a frequency having a half period coinciding with the on-time of the transistor.
Inventors
- 👤 Robert L. Garrison
- 👤 Harold L. Jr. Rothwell
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 20:58
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; H05B41/288; H05B41/2885; H05B41/2881; H05B41/2882; Y; Y02; Y02B; Y02B20/00; Y10; Y10S; Y10S315/00; Y10S315/07
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
157 words
A lamp operating circuit comprising, in combination: a DC power source having first and second output terminals; a first inductance means and a controlled switch means series-connected rn that order between the first and second output terminals of said DC power source; a second inductance means coupled across the output terminals of said DC power source; an oscillator coupled to said controlled switch means for respectively operating the same at predetermined intervals, whereby said controlled switch means and first and second inductance means function as an inverter having an AC output across the combination of said first and second inductance means; and means for connecting first and second terminals of a low wattage HID lamp across said inverter; said connecting means including a ballast capacitor means coupled between said first inductance means and the first terminal of said lamp, and a ballast inductance means coupled between said second inductance means and the second terminal of said lamp.
Claim 2
Dependent Claim
157 words
A lamp operating circuit comprising, in combination: a DC power source having first and second output terminals; a first inductance means and a controlled switch means series-connected rn that order between the first and second output terminals of said DC power source; a second inductance means coupled across the output terminals of said DC power source; an oscillator coupled to said controlled switch means for respectively operating the same at predetermined intervals, whereby said controlled switch means and first and second inductance means function as an inverter having an AC output across the combination of said first and second inductance means; and means for connecting first and second terminals of a low wattage HID lamp across said inverter; said connecting means including a ballast capacitor means coupled between said first inductance means and the first terminal of said lamp, and a ballast inductance means coupled between said second inductance means and the second terminal of said lamp.
Claim 3
Dependent Claim
35 words
The circuit of Claim 1 further including a voltage multiplier starting circuit connected across said first and second terminals of the lamp, said starting circuit being substantially shorted out during normal operation of said lamp.
Claim 4
Dependent Claim
23 words
The circuit of Claim wherein said first and second inductance means function as a transformer to step-up the voltage applied across said lamp.
Claim 5
Dependent Claim
35 words
The circuit of Claim 3 wherein said oscillator has a frequency in the kilohertz range, whereby operation of said controlled switch means by the oscillator provides an output from said inverter in said kilohertz range.
Claim 6
Dependent Claim
36 words
The circuit of Claim 4 further including a first diode means connected across said controlled switch means, and a second diode means series-connected between said second inductance means the second output terminal of said-DC power source.
Claim 7
Dependent Claim
115 words
The circuit of Claim 5 further including a third inductance means connected between said ballast inductance means and the junction of said second inductance means and second diode means, whereby said ballast inductance means, said lamp and said ballast capacitor means are series connected across the combination of said first, second and third inductance means, said third inductance means functioning to further step up the voltage applied across said lamp, and said first inductance means has an inductance value selected to store an amount of energy approximately equal to W/f during the conducting period of said switch means, where W is the power rating of said lamp and f is the frequency of said oscillator.
Claim 8
Dependent Claim
16 words
The circuit of Claim 6 wherein said oscillator frequency is in the order of 20 kilohertz.
Claim 9
Dependent Claim
40 words
The circuit of Claim 6 wherein the capacitance value of said capacitor means is selected so that the peak voltage across said switch means during the non-conducting period thereof is approximately double the output voltage of said DC power source.
Claim 10
Dependent Claim
88 words
The circuit of Claim 1 wherein said ballast inductance means is selected to resonate with said ballast capacitor means whereby the switching current waveform is substantially a half sinewave pulse, with both the turn-on and turn-off transition of said switching means occuring at zero current, thereby substantially eliminating switching losses, and wherein said ballast inductance means is operative during the conducting period of said switch means to provide an impedance load in the lamp circuit for permitting full conduction of said switch means with a minimized power loss.
Claim 11
Dependent Claim
135 words
1 0 . The circuit of Claim 1 wherein said controlled switch means is a transistor having base, collector and emitter electrodes, said base being coupled to the output of said oscillator, and said collector and emitter electrodes being coupled in a series circuit between said first inductance means and the second output terminal of said DC power source, and further including a first diode connected across the emitter and collector electrodes of said transistor as a reverse current bypass, and a second diode series connected-with said second inductance means across the output of said DC power source and disposed in circuit between the second inductance means and said second output terminal of the DC source, said second diode being selected to prevent the voltage across said transistor collector-emitter electrodes from exceeding a predetermined value.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.