High-pressure discharge lamp with starting aid and method for producing the same
View Patent ↗In a high-pressure discharge lamp including a ceramic discharge vessel, a secure connection between a hybrid antenna as starting aid and a leadthrough of the discharge vessel is provided by virtue of the fact that a means between leadthrough and extension limits the ohmic resistance between leadthrough and hybrid antenna preferably to at most 100Ω.
1. A high-pressure discharge lamp, comprising:
a discharge vessel composed of ceramic;
at least one leadthrough for an electrode, fuse-sealed into an end of the discharge vessel by means of glass solder; and
a starting aid comprising:
at least two rings around the discharge vessel;
a connection line connecting the two rings; and
an extension part extending from one of the rings to a region proximal to the leadthrough;
wherein a contact protrusion between the leadthrough and the extension part limits the ohmic resistance to at most 10 kΩ.
2. The high-pressure discharge lamp as claimed in claim 1 , wherein the contact protrusion limits the ohmic resistance between leadthrough and extension part to at most 100Ω.
3. The high-pressure discharge lamp as claimed in claim 1 , wherein the extension part ends in an end piece which is spaced apart from the leadthrough and at least partly surrounds the leadthrough.
4. The high-pressure discharge lamp as claimed in claim 3 , wherein the spaced apart distance between the end piece and the leadthrough is at most twice the magnitude of the diameter of the leadthrough.
5. The high-pressure discharge lamp as claimed in claim 4 , wherein the spaced apart distance between the end piece and the leadthrough is at most the same magnitude as the diameter of the leadthrough.
6. A method for producing a high-pressure discharge lamp as claimed in claim 5 , wherein a forming process is applied, and wherein, for the purpose of forming, a pulsed voltage is connected between the hybrid antenna, on the one hand, and the leadthrough, on the other hand.
7. The method as claimed in claim 6 , wherein the voltage present is a maximum of 6 kV, in that the pulse duration is between 100 ns and 100 μs, and in that the energy introduced into the channel is 0.1 mJ to 10 mJ.
8. The high-pressure discharge lamp as claimed in claim 3 , wherein the leadthrough is a tube or pin, wherein an outwardly projecting local projection is fitted thereto as the contact protrusion, and wherein the projection has a cutting edge which makes contact with the extension part at the end piece thereof.
9. The high-pressure discharge lamp as claimed in claim 8 , wherein the cutting edge is in the direction toward the electrode.
10. The high-pressure discharge lamp as claimed in claim 3 , wherein the means is a conductive channel in the region of the glass solder which contains metal alongside glass solder and which extends in a line-like manner between end piece and leadthrough, and wherein a forming process has been applied, in in which the electrically insulating or high-impedance connection between the leadthrough and the extension part in the channel is made to have low impedance.
11. The high-pressure discharge lamp as claimed in claim 1 , wherein a mechanical pressure is exerted between the discharge vessel and the leadthrough during the fuse-sealing process.
12. The high-pressure discharge lamp as claimed in claim 1 , wherein the leadthrough is a tube or pin, and wherein an outwardly projecting projection is fitted thereto as the contact protrusion, which projection makes contact with the extension part.
13. The high-pressure discharge lamp as claimed in claim 12 , wherein the projection is embodied as a step.
14. The high-pressure discharge lamp as claimed in claim 12 , wherein the projection is embodied as a step with a cutting edge in the direction of the electrode.
15. The high-pressure discharge lamp as claimed in claim 12 , wherein the leadthrough is a tube or pin, wherein an outwardly projecting local projection is fitted thereto as the contact protrusion, and wherein the projection has, in the direction toward the electrode, one or a plurality of contact points making contact with the extension part at the end piece thereof.
16. The high-pressure discharge lamp as claimed in claim 15 , wherein the contact points are ends of a scraped portion.
17. The high-pressure discharge lamp as claimed in claim 1 , wherein the ohmic resistance is 0.2 to 1Ω.
18. The high-pressure discharge lamp as claimed in claim 17 , wherein the projection is embodied as a step with a cutting edge in the direction of the electrode.