Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
115 words
A discharge lamp lighting apparatus comprising DC power source means, inverter means connected to said DC power source means, transformer means having input and output windings, said input winding being connected in parallel with said inverter means, and at least one discharge lamp having a pair of filaments connected to said output winding of said transformer means, characterized in that said inverter means (36, 36') is connected to said DC power source means via a series resonance circuit constituted by an inductor (58) and a first capacitor (60), and said input winding (68, 86) of said transformer means (66, 84) is connected in parallel with said first capacitor (60) of said inverter means (36, 36').
Claim 2
Dependent Claim
32 words
An apparatus according to claim 1, characterized in that said inverter means (36, 36') has first and second switching means (38, 40) connected in series with said DC power source means (10).
Claim 3
Dependent Claim
58 words
An apparatus according to claim 2, characterized in that said inverter means (36) has second and third capacitors (42, 44) connected in series with said DC power source means (10), and said series resonance circuit is connected between between said first and second switching means (38, 40) and a node between said second and third capacitors (42, 44).
Claim 4
Dependent Claim
58 words
An apparatus according to claim 2, characterized in that said inverter means (36') has a fourth capacitor (82) connected to said DC power source means (10) and said inductor (58) as one terminal of said series resonance circuit, and the other terminal of said series resonance circuit is connected between said first and second switching means (38, 40).
Claim 5
Dependent Claim
22 words
An apparatus according to claim 2, characterized in that said first and second switching means (38, 40) are constituted by field-effect transistors.
Claim 6
Dependent Claim
65 words
An apparatus according to claim 1, characterized in that said transformer means (66) further includes a voltage detection winding (90), and further comprising control means (92, 94), connected between said voltage detection winding (90) and said first and second switching means (38, 40), for controlling said first and second switching means (38, 40) in accordance with a voltage detected by said voltage detection winding (90).
Claim 7
Dependent Claim
58 words
An apparatus according to claim 6, characterized in that said control means includes a voltage detection circuit (92) for detecting the voltage detected by said voltage detection winding (90) and a control circuit (94) for alternately switching on/off said first and second switching means (38, 40) in accordance with the voltage detected by said voltage detection circuit (92).
Claim 8
Dependent Claim
49 words
An apparatus according to claim 7, characterized in that said control means further includes a safety circuit (96) for stopping an operation of said first and second switching means (38, 40) controlled by said control circuit (92) when an abnormal voltage is detected by said voltage detection winding (90).