Electric device provided with a gas and/or vapor discharge lamp

Claim 2

An electric device comprising a discharge lamp having an electric discharge tube with at least two main electrodes and an auxiliary electrode, two input terminals adapted for connection to an AC voltage source to supply the lamp with power, a cascade circuit including two series circuits each of which comprises a rectifier and a capacitor in series, means connecting the second series circuit to form a closed circuit with the rectifier of the first series circuit, a first resistor, means connecting an electrode path of the discharge tube and said first resistor in shunt with the capacitor of the second series circuit, said electrode path being formed between the auxiliary electrode and a main electrode of the discharge tube, means connecting the main electrode path formed between the main electrodes of the discharge tube in series with a current limiting circuit element and in shunt with a part of the cascade circuit, which part comprises at least the capacitor of the second series circuit, and means connecting the first series circuit of the cascade circuit directly to the input terminals of the device.

Claim 3

An electric device as claimed in claim 1, characterized in that the current limiting circuit element comprises a second resistor.

Claim 4

An electric device as claimed in claim 2, wherein the second resistor comprises a filament so that the combination of the discharge tube and the second resistor forms a mixed-light lamp.

Claim 5

An electric device as claimed in claim 1, wherein the part of the cascade circuit that is shunted by the series combination of the tube main electrode path and the current limiting circuit element comprises the series connection of the second series circuit and the capacitor of the first series circuit.

Claim 6

An electric device as claimed in claim 1, wherein the part of the cascade circuit that is shunted by the series combination of the tube main electrode path and the current limiting circuit element includes the capacitor of the second series circuit only.

Claim 7

An electric device as claimed in claim 3, characterized in that all circuit elements of the device are located within the mixed-light lamp.

Claim 8

A ballast and starting circuit for an electric discharge tube having two main electrodes and an auxiliary electrode comprising, a pair of input terminals for supplying an AC voltage to the circuit, a voltage doubler circuit comprising first and second stages connected in cascade to said input terminals, the first stage including a first capacitor and a first rectifier connected in a first series circuit, the second stage including a second capacitor and a second rectifier connected in a second series circuit across the first rectifier so that the first and second rectifiers and the second capacitor form a closed loop circuit, a first impedance element, means connecting the electrode path formed between the tube auxiliary electrode and a main electrode in a series arrangement with said first impedance element and said series arrangement in shunt with the second capacitor, a second impedance element, means connecting the second impedance element and the main electrode path of the discharge tube in series across the input terminals and in shunt with a part of the cascade circuit that includes at least the second capacitor, said first series circuit being connected directly to said input terminals.

Claim 9

A ballast and starting circuit for an electric discharge tube having two main electrodes and an auxiliary electrode comprising, a pair of input terminals for supplying an AC voltage to the circuit, a voltage doubler circuit comprising first and second stages connected in cascade to said input terminals, the first stage including a first capacitor and a first rectifier connected in a first series circuit, the second stage including a second capacitor and a second rectifier connected in a second series circuit across the first rectifier so that the first and second rectifiers and the second capacitor form a closed loop circuit, a first impedance element, means connecting the electrode path formed between the tube auxiliary electrode and a main electrode in a series arrangement with said first impedance element and said series arrangement in shunt with the second capacitor, a second impedance element, means connecting the second impedance element and the main electrode path of the discharge tube in series across the input terminals and in shunt with a part of the cascade circuit that includes at least the second capacitor, said first series circuit being connected directly to said input terminals.

Claim 10

A circuit as claimed in claim 7 wherein said first and second impedance elements comprise a first resistor and a second filament resistor.

Claim 11

A circuit as claimed in claim 7 wherein said first capacitor, said second rectifier and said second capacitor are connected to form a further series circuit across the input terminals and the series combination of the second impedance element and the tube main electrode path shunts said further series circuit.

Claim 12

A circuit as claimed in claim 7 wherein the part of the cascade circuit shunted by the series combination of the second impedance element and the tube main electrode path includes only said second capacitor.

Claim 13

A circuit as claimed in claim 7 wherein said first capacitor and said second rectifier are connected in series with the second impedance element and the tube main electrode path across the input terminals.

Claim 14

A circuit as claimed in claim 7 wherein said first and second rectifiers comprise first and second diodes, respectively, connected with the same polarity in the closed loop circuit.

Claim 15

A circuit as claimed in claim 7 wherein said second impedance element includes an infra-red radiation element and said discharge tube emits ultra-violet radiation.

Claim 16

A circuit as claimed in claim 7 wherein the series combination of the second impedance element and the tube main electrode path is connected directly across the input terminals and in shunt with the voltage doubler circuit.