Gas discharge lamp, in particular for motor-vehicle headlights

A gaseous-discharge lamp for use in a motor-vehicle headlamp, comprising:

• a burner vessel formed of a glass and containing a gas;
• a first gas-tight electrode bushing;
• a first main electrode extending into the burner vessel via the first gas-tight electrode bushing;
• a second gas-tight electrode bushing;
• a second main electrode extending into the burner vessel via the second gas-tight electrode bushing, an arc gap along which an electric arc develops during operation being formed between an end region of the first main electrode and an end region of the second main electrode;
• and
• an arrangement for producing, as an ignition gap that is spatially separated from the arc gap, at least one of a creepage spark gap along an inner wall of the burner vessel and a spark gap shorter than the arc gap, the arrangement for producing the creepage spark gap including at least one ignition electrode;
• wherein the burner vessel includes:
• a combustion chamber,
• a first tubular extension extending from the combustion chamber along a first direction and containing the first main electrode, the first tubular extension including an end region containing the first gas-tight electrode bushing, and
• a second tubular extension extending from the combustion chamber along a second direction that is opposite to the first direction and containing the second main electrode, the second tubular extension including an end region containing the second gas-tight electrode bushing, and
• wherein the at least one ignition electrode includes a metallic coating that extends along an inside surface of the burner vessel to one of the first gas-tight electrode bushing and the second gas-tight electrode bushing in order to form a connection with a corresponding one of the first main electrode and the second main electrode.

A gaseous-discharge lamp for use in a motor-vehicle headlamp, comprising:

• a burner vessel formed of a glass and containing a gas;
• a first gas-tight electrode bushing;
• a first main electrode extending into the burner vessel via the first gas-tight electrode bushing;
• a second gas-tight electrode bushing;
• a second main electrode extending into the burner vessel via the second gas-tight electrode bushing, an arc gap along which an electric arc develops during operation being formed between an end region of the first main electrode and an end region of the second main electrode;
• and
• an arrangement for producing, as an ignition gap that is spatially separated from the arc gap, at least one of a creepage spark gap along an inner wall of the burner vessel and a spark gap shorter than the arc gap, the arrangement for producing the creepage spark gap includes at least one ignition electrode;
• wherein the burner vessel includes:
• a combustion chamber,
• a first tubular extension extending from the combustion chamber along a first direction and containing the first main electrode, the first tubular extension including an end region containing the first gas-tight electrode bushing, and
• a second tubular extension extending from the combustion chamber along a second direction that is opposite to the first direction and containing the second main electrode, the second tubular extension including an end region containing the second gas-tight electrode bushing,
• wherein the at least one ignition electrode includes a metallic coating that extends on an outside surface of the burner vessel to a connection contact element in order to form a connection with one of the first main electrode and the second main electrode, and
• wherein the at least one ignition electrode is arranged at least along an area of the arc gap as one of a lamellar and a light-reflector type metallic coating.

A gaseous-discharge lamp for use in a motor-vehicle headlamp, comprising:

• a burner vessel formed of a glass and containing a gas;
• a first gas-tight electrode bushing;
• a first main electrode extending into the burner vessel via the first gas-tight electrode bushing;
• a second gas-tight electrode bushing;
• a second main electrode extending into the burner vessel via the second gas-tight electrode bushing, an arc gap along which an electric arc develops during operation being formed between an end region of the first main electrode and an end region of the second main electrode;
• and
• an arrangement for producing, as an ignition gap that is spatially separated from the arc gap, at least one of a creepage spark gap along an inner wall of the burner vessel and a spark gap shorter than the arc gap, the arrangement for producing the creepage spark gap including at least one ignition electrode, the at least one ignition electrode being arranged inside the burner vessel;
• wherein the burner vessel includes:
• a combustion chamber,
• a first tubular extension extending from the combustion chamber along a first direction and containing the first main electrode, the first tubular extension including an end region containing the first gas-tight electrode bushing, and
• a second tubular extension extending from the combustion chamber along a second direction that is opposite to the first direction and containing the second main electrode, the second tubular extension including an end region containing the second gas-tight electrode bushing;
• wherein each one of the first main electrode and the second main electrode is connected to the at least one ignition electrode, and wherein at least one of the spark gap and the creepage spark gap is formed between the at least one ignition electrode and a corresponding one of the first main electrode and the second main electrode.

A gaseous-discharge lamp for use in a motor-vehicle headlamp, comprising:

• a burner vessel formed of a glass and containing a gas;
• a first gas-tight electrode bushing;
• a first main electrode extending into the burner vessel via the first gas-tight electrode bushing;
• a second gas-tight electrode bushing;
• a second main electrode extending into the burner vessel via the second gas-tight electrode bushing, an arc gap along which an electric arc develops during operation being formed between an end region of the first main electrode and an end region of the second main electrode;
• and
• an arrangement for producing, as an ignition gap that is spatially separated from the arc gap, at least one of a creepage spark gap along an inner wall of the burner vessel and a spark gap shorter than the arc gap, the arrangement for producing the creepage spark gap includes at least one ignition electrode;
• wherein the burner vessel includes:
• a combustion chamber,
• a first tubular extension extending from the combustion chamber along a first direction and containing the first main electrode, the first tubular extension including an end region containing the first gas-tight electrode bushing, and
• a second tubular extension extending from the combustion chamber along a second direction that is opposite to the first direction and containing the second main electrode, the second tubular extension including an end region containing the second gas-tight electrode bushing,
• wherein the at least one ignition electrode includes a metallic coating that extends on an outside surface of the burner vessel to a connection contact element in order to form a connection with one of the first main electrode and the second main electrode, and
• wherein the metallic coating includes one of a non-oxidizing metal having a melting point of over about 1000° C. and a less precious metal covered with a protective layer that is impermeable to oxygen and has a melting temperature of over about 1100° C.