Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
232 words
A fluorescent lamp arrangment comprising a blocking oscillator transistor inverter having a primary winding, a feedback winding, and a secondary winding, there being a substantial step up ratio between primary and secondary windings, two fluorescent tubes, means connecting a filament of at least one tube in series with the feedback winding whereby the filament is preheated by the collector current of the transistor, a conductive connection between the preheated filament of the said one tube and one filament of the second tube, a connection between one end of the secondary winding and the other filament of said one tube, and a switch connected to the other end of the secondary winding, said switch in one position connecting the said other end to the said preheated filament of said one tube and in another position connecting the said other end of the secondary winding to the other filament of said second tube, whereby 1. when one tube only is to be energized the secondary winding is connected across the said preheated filament and the other filament of that tube, and 2. when both tubes are to be energized the ends of the secondary winding are connected one to the nonpreheated filament of the said one tube, and the other end of the winding to the other filament of the second tube, there being a series path for the lighting current through both tubes.
Claim 2
Dependent Claim
232 words
A fluorescent lamp arrangment comprising a blocking oscillator transistor inverter having a primary winding, a feedback winding, and a secondary winding, there being a substantial step up ratio between primary and secondary windings, two fluorescent tubes, means connecting a filament of at least one tube in series with the feedback winding whereby the filament is preheated by the collector current of the transistor, a conductive connection between the preheated filament of the said one tube and one filament of the second tube, a connection between one end of the secondary winding and the other filament of said one tube, and a switch connected to the other end of the secondary winding, said switch in one position connecting the said other end to the said preheated filament of said one tube and in another position connecting the said other end of the secondary winding to the other filament of said second tube, whereby 1. when one tube only is to be energized the secondary winding is connected across the said preheated filament and the other filament of that tube, and 2. when both tubes are to be energized the ends of the secondary winding are connected one to the nonpreheated filament of the said one tube, and the other end of the winding to the other filament of the second tube, there being a series path for the lighting current through both tubes.
Claim 3
Dependent Claim
52 words
when both tubes are to be energized the ends of the secondary winding are connected one to the nonpreheated filament of the said one tube, and the other end of the winding to the other filament of the second tube, there being a series path for the lighting current through both tubes.
Claim 4
Dependent Claim
52 words
when both tubes are to be energized the ends of the secondary winding are connected one to the nonpreheated filament of the said one tube, and the other end of the winding to the other filament of the second tube, there being a series path for the lighting current through both tubes.
Claim 5
Dependent Claim
30 words
A fluorescent lamp arrangement as claimed in claim 1 wherein the one filament of the second tube is connected in parallel with the preheated filament of the said one tube.
Claim 6
Dependent Claim
30 words
A fluorescent lamp arrangement as claimed in claim 1 wherein the one filament of the second tube is connected in series with the preheated filament of the said one tube.
Claim 7
Dependent Claim
30 words
A fluorescent lamp arrangement as claimed in claim 1 comprising a capacitor connected between the one filament of the second tube and the preheated filament of the said one tube.
Claim 8
Dependent Claim
49 words
A fluorescent lamp arrangement as claimed in claim 1 wherein the feedback winding is centre-tapped, the preheated filament of said one tube is connected across one half of the feedback winding, and the one filament of the other tube is connected across the other half of the feedback winding.
Claim 9
Dependent Claim
38 words
A fluorescent lamp arrangement as claimed in claim 1 wherein the one filament of the second tube is connected to the collector of the transistor, and to a capacitor connected to the collector and to the emitter circuit.
Claim 10
Dependent Claim
27 words
A fluorescent lamp arrangement as claimed in claim 1 including a capacitor, said capacitor being connected between the other end of the secondary winding and said switch.
Claim 11
Dependent Claim
30 words
A fluorescent lamp arrangement as claimed in claim 1 including a capacitor connected between the one filament of the second tube and the preheated filament of the said one tube.
Claim 12
Dependent Claim
38 words
A fluorescent lamp arrangement as claimed in claim 1 including a capacitor connected to said switch so as to be in series between the secondary winding and the said one tube when said one tube only is energised.
Claim 13
Dependent Claim
30 words
A fluorescent lamp arrangement as claimed in claim 9 wherein the one filament of the second tube is connected in series with the preheated filament of the said one tube.