Abstract: The lamp uses a sealing system with a ceramic supporting element (17) having a short length LA together with a W—Nb leadthrough part (18, 19, 20) and a specially adapted glass solder (21), which is based on an Al2O3 rare earth oxide system. In this case, the W part is accommodated in the supporting part over a length LW of 1 mm, and the aspect ratio LW/DUW, formed from the length LW and the diameter DUW of the W part, is at least 10.

Abstract: An arc tube of ceramic material has an aluminum nitride (AlN) end structure (36) wherein a feedthrough (30) is sealed by direct bonding. Said feedthrough is comprised of a refractory metal, W or Mo, that is aluminized on its outer surface. Preferably, the feedthrough is a Mo pipe that had been provided with a Mo3191Al layer (36) prior to direct bonding, the aluminized layer provides a bonding interface between the AlN ceramic and the refractory metal feedthrough.

Abstract: The invention relates to a metal halide lamp comprising a ceramic discharge vessel (10), characterized in that an MoV leadthrough is connected to a PCA element (Al2O3) by means of a specific adhesive layer containing Al and Mo.

Abstract: A high-pressure discharge lamp may include a ceramic discharge vessel and a longitudinal axis, with electrodes respectively being led out from the discharge vessel by means of a feed-through via capillaries, wherein a tubular cermet part, which consists of individual layers of different composition layered axially in succession, is fitted on the capillary, each layer containing Mo and Al2O3, the proportion of Mo in the first layer facing toward the capillary being from 3 to 15 vol. % and in the last layer being from 85 to 97 vol. %, and a molybdenum cover cap, the cover cap being welded to the feed-through and the cover cap being connected to the cermet part by means of solder containing metal, and the connection between the capillary and the cermet part being established by means of high-melting glass solder or sinter-active Al2O3 powder.

Abstract: A high-pressure discharge lamp may include an elongated ceramic discharge vessel, wherein an electrode projects into the discharge vessel in each end area, wherein the electrode is attached to a bushing arranged in a capillary tube, wherein the internal diameter is reduced to at most 85% of the internal diameter of the elongated ceramic discharge vessel in the end area, such that an end surface remains at the end of the vessel, which has an internal diameter of at least 15% of the internal diameter, wherein a gap of most 20 ?m remains between the bushing and the inner wall of the capillary, wherein the ratio between the areas which are formed by the internal diameter of the capillary and the diameter of the end surface is in the range from 0.06 to 0.12.

Abstract: The invention relates to a high-pressure discharge lamp, having a ceramic discharge vessel comprising a capillary (5) on the end. An electrode system is incorporated into the capillary, said electrode system having a three-part bushing (6). The bushing comprises a first, front-end part (15) in the shape of a pin, a center part comprising a core pin (16) and a Mo-winding (17), and an outer part that is a niobium pin (18). Each of the three parts has a different gap width.

Abstract: A high-pressure discharge lamp may include a ceramic discharge vessel that encloses a discharge volume and at whose ends capillaries are fitted, an electrode system being led through in each capillary and sealed there, use being made of at least one electrode system that is based on tungsten and has an electrode head made from tungsten as first segment and a shaft made from tungsten as second segment, as well as a multipartite leadthrough having a pin projecting on the outside at the end of the capillary, wherein the multipartite leadthrough has a central cylindrical leadthrough part made from tungsten as third segment of the electrode system inside the capillary, which adjoins the second segment, as well as a fourth multipartite segment inside the capillary, consisting of a core pin that is made from tungsten, has a diameter of at most 300 ?m and is partially surrounded by a tubular sleeve, the pin being connected to the projecting pin, a gap remaining between the sleeve and projecting pin, and the end of th

Abstract: The invention relates to a metal halide lamp comprising a ceramic discharge vessel (21), characterized in that a molybdenum leadthrough (11) is connected to a cermet stopper (15) via an intermetal interface gradient (20).

Abstract: An opaque zone in the polycrystalline (PCA) discharge vessel of a high intensity discharge lamp may be made by creating residual pores in predetermined regions of the final-sintered discharge vessel. The control over the placement of the opaque zone is achieved by forming a carbonaceous residue in a specific region of the discharge vessel prior to final sintering. During sintering, the carbonaceous material causes residual porosity in the sintered PCA. The higher emissivity of the opaque PCA provides localized cooling in order to provide more control over the condensate behavior in the discharge vessel.

Abstract: A thick-film resistance 9 with a conductive path 8 of electrically conductive material is provided in the case of a fuel level transmitter for a fuel tank of a motor vehicle. The conductive path 8 is contacted in a sliding manner by a contact element. The material of the contact element exhibits a silver content, which has been reduced in such a manner, that an increase in the resistance of the contact ascribable to the formation of silver compounds, especially silver sulfide, silver sulfite and silver sulfate on the contacting surfaces is negligible.

Abstract: A ceramic discharge vessel is provided wherein the discharge vessel has a ceramic body and at least one expanded reaction-bonded aluminum oxide member hermetically sealed to the ceramic body. The method of making the discharge vessel includes (a) forming a ceramic body; (b) forming a reaction-bonded aluminum oxide member in a green state by compacting a mixture of aluminum metal and aluminum oxide powders; (c) assembling the ceramic body and the reaction-bonded aluminum oxide member in the green state to form an assembly; and (d) reaction sintering the assembly to cause the reaction-bonded aluminum oxide member to expand and form a hermetic seal with the ceramic body.

Abstract: The invention relates to a high-pressure discharge lamp, in particular a metal halide high-pressure discharge lamp, and a method for operating this lamp with the aid of a square-wave alternating current. According to the invention, the electrodes (2) of the lamp are dimensioned such that during operation of the lamp with its prescribed nominal power and with a substantially square-wave alternating current the product of the current density in the electrodes (2) and the cube root of the root mean square value of the alternating current has a constant value of between 5 A4/3mm−2 and 10 A4/3mm−2 during the stable operating state of the high-pressure discharge lamp after termination of the ignition phase.

Abstract: A fuel-level indicator for a motor vehicle fuel tank includes an insulating base carrier; an electrically conducting slide track mounted on the base carrier and containing at least one metal; and a movable transmitter arm carrying a slide contact and being in sliding engagement with the slide track. The slide track is free from silver.

Abstract: At least at one end of a discharge lamp, for example a metal-halide discharge lamp or a sodium high-pressure discharge lamp, which has a ceramic discharge vessel (4), a feed-through (9, 10; 30) is provided which includes a cermet. The cermet may be in pin or capillary tube form, and has a metal content which is so high that it can be welded like a metal. The cermet can be directly sintered into an end plug (26) or into an end portion (34a, 34b) of the vessel itself. The seal thus is effected by a sealing arrangement (11, 21, 34a, 34b, 31) devoid of glass melt, which would be degraded by attack of corrosive fills within the lamp, while additionally having the capability of withstanding higher operating temperatures.

Abstract: The discharge vessel has two ends (6), which are closed off by ceramic pl which each contain an elongate capillary tube (12), an electrically conductive lead-through (9, 10) comprising two parts (13, 14) being guided in a vacuum-tight manner through this plug capillary tube (12). The inner part (14) is a pin made of a halide-resistant metal (tungsten), the diameter of which is at most 0.4 mm and which is surrounded by a tubular casing (20, 21) made of ceramic material which consists of a concentric aluminum oxide tube (sleeve), the outer part (13), over its entire length, and the inner part (14), at least over a length of 1 mm from the beginning of the sleeve (20, 21), being sealed off by means of soldering glass (18).

Abstract: To provide a tight seal for a fill bore in the wall or an end plug of a dharge vessel for high-pressure discharge lamps, a fill bore is provided either through the wall--in the region of the plug--or through a plug, and the fill bore is then closed by a stopper in combination with a melt sealing material, which is so chosen that the sealing material and plug-like member combination provide a minimum of sealing material exposed to the fill in the discharge volume. The fill in the discharge volume of the discharge vessel is ionizable and, for example containing halides, is highly corrosive to the sealing material. The lamp can be made by inserting a stopper into the filling bore, applying, with the stopper in place in the filling bore, sealing material to the outer end of the filling bore, and heating the portion of the discharge vessel to liquefying temperature of the sealing material to liquefy the sealing material and hence close off the fill bore.

Abstract: A vacuum-tight seal, particularly for an arc tube or discharge vessel for a metal halide or sodium high-pressure discharge lamp, is made by forming the arc tube of transparent ceramic, typically Al.sub.2 O.sub.3, having two open ends, into which connecting plugs (3), with central openings, are sealed. Open metal tubes (4) fitting into the openings of the plugs (3) are then vacuum-tightly sintered therein. An electrode system (5, 10, 10'), forming a subassembly with a current supply lead or lead-through (6, 11, 14, 15, 20, 24) is provided, having an outer diameter fitting into the metal tube.

Abstract: A method for producing a metal-halide discharge lamp with a ceramic dische vessel is distinguished in that first both ends (6a, 6b) are equipped with electrode systems and sealed off, but a filling bore (15) remains in the vicinity of the pump end (6a) and is not closed until after the filling.