Patent-treuhand-gesellschaft F. Elektrische Gluehlampen Mbh

Osram Sylvania Inc.

Osram Ag

Ngk Insulators, Inc.

Osram Gmbh

Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh

Patent-truehand-gesellschaft Fuer Electriche Gluelampen Mbh

Roland Huettinger

Stefan Juengst

Stefan Kotter

George C Wei

Steffen Walter

Juergen Heider

Christopher A Tarry

Dieter Lang

Wolfgang Pabst

Philipp Erhard

Khanh Pham Gia

Gerhard Mitic

Osamu Asano

Hartmuth Bastian

Ulrich Henger

Kouichiro Maekawa

Rita Tiedt

Jens Clark

A lighting device () comprising at least one light source (), at least one base () thermally and electrically operationally connected to the light source (), and at least one bulb fitting () provided for receiving the base (). The base () has at least one first heat transfer surface () and the bulb fitting () has at least one second heat transfer surface () in contact with the first heat transfer surface () either directly or by way of a foil (). At least one device () is provided for exerting a predefined press force between the first heat transfer surface () and the second heat transfer surface ().

Lighting device having a socket and bulb fitting

A high pressure discharge lamp may include a ceramic discharge vessel and a longitudinal axis, wherein at least one electrode is led out of the discharge vessel by means of a metal-containing feed-through, wherein the feed-through is connected to one end of the discharge vessel by way of a ceramic-containing adjustment part, wherein the adjustment part is tubular and consists of individual layers with different compositions, at least two materials A and B forming a plurality of layers of the adjustment part, these materials being chosen such that their coefficient of thermal expansion is between that of the feed-through and that of the end of the discharge vessel or at most is just outside, the layer thickness of each layer being so low that no shearing forces can occur, and the layer thickness of each layer of the same material being different.

High pressure discharge lamp

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.

Ceramic discharge vessel having an opaque zone and method of making same

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 AlO, 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 AlOpowder.

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 (,), a feed-through (,) 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 (,) or into an end portion (,) of the vessel itself. The seal thus is effected by a sealing arrangement (,) 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.

Metal halide or sodium high pressure lamp with cermet of alumina, molybdenum and tungsten

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).

Metal-halide lamp with specific lead through structure

Ceramic discharge vessel for a high-pressure discharge lamp, having a

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. After mounting one of the electrode systems and lead-through into the metal tube (4), and welding the lead-through to the metal tube, the vessel can be evacuated through the still open tube (4) at the other end, supplied with suitable fill substances and an ignition gas, such as argon or xenon, and the second electrode system then introduced, and welded, for example by a laser, to the outer end of the other metal tube (4). The arrangement permits use of molybdenum tubes, molybdenum lead-throughs, in Al.sub.2 O.sub.3 ceramic, in spite of different thermal coefficients of expansion. Preferably, the metal tube extends beyond the end face of the vessel and/or sealing plug (3), to permit free access during the welding step and reduce heat transfer into the interior of the arc tube or discharge vessel (1).

Method of making a vacuum-tight seal between a ceramic and a metal part,

Method for producing a metal-halide discharge lamp with a ceramic

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Kaufering, Germany

Roland Huettinger