WO1991009417A1 - Tube de reception d'electrodes pour lampes a decharge en arc - Google Patents

Tube de reception d'electrodes pour lampes a decharge en arc Download PDF

Info

Publication number
WO1991009417A1
WO1991009417A1 PCT/US1990/007404 US9007404W WO9109417A1 WO 1991009417 A1 WO1991009417 A1 WO 1991009417A1 US 9007404 W US9007404 W US 9007404W WO 9109417 A1 WO9109417 A1 WO 9109417A1
Authority
WO
WIPO (PCT)
Prior art keywords
tube
electrode
feedthrough
arc tube
assembly
Prior art date
Application number
PCT/US1990/007404
Other languages
English (en)
Inventor
Luk +Di Veraghtert
Elliot F. Wyner
David A. Goodman
Original Assignee
Gte Products Corporation
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gte Products Corporation filed Critical Gte Products Corporation
Publication of WO1991009417A1 publication Critical patent/WO1991009417A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/24—Manufacture or joining of vessels, leading-in conductors or bases
    • H01J9/32—Sealing leading-in conductors
    • H01J9/323—Sealing leading-in conductors into a discharge lamp or a gas-filled discharge device
    • H01J9/326—Sealing leading-in conductors into a discharge lamp or a gas-filled discharge device making pinched-stem or analogous seals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00—Gas-discharge or vapour-discharge lamps
    • H01J61/02—Details
    • H01J61/36—Seals between parts of vessels; Seals for leading-in conductors; Leading-in conductors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/24—Manufacture or joining of vessels, leading-in conductors or bases
    • H01J9/28—Manufacture of leading-in conductors

Definitions

  • This invention relates to arc tube assemblies for high pressure arc discharge lamps and, more particularly, to electrode feedthrough structures and methods of manufacturing such structures.
  • High pressure sodium arc lamps have been in commercial production for many years and have been subject to many improvements in design, materials and processing.
  • Such lamps include a translucent ceramic arc tube, an outer envelope including an electrical connector, and a frame for supporting the arc tube within the outer envelope.
  • the frame is electrically conductive and carries power to the arc tube.
  • the arc tube is typically fabricated from polycrystalline alumina or yttria and contains an amalgam of mercury and sodium for producing light having a desired output spectrum.
  • Tungsten or molybdenum electrodes are positioned within the arc tube at opposite ends and are attached to feedthroughs selected to have thermal expansion characteristics closely matched to those of the ceramic arc tube.
  • the feedthroughs are hermetically sealed in openings at opposite ends of the arc tube.
  • Niobium usually containing about 1% zirconium by weight, is the preferred feedthrough material for alumina arc tubes.
  • the feedthrough is a niobium tube.
  • a tungsten coil electrode is attached to the niobium tube by a tungsten electrode support rod.
  • the opening in each end of the arc tube is sufficiently large for insertion of the electrode and the niobium tube.
  • An insert button is sintered directly into the end of the arc tube, and a ceramic sealing button or ring is sealed with a low melting point ceramic frit to the end of the arc tube over the feedthrough to extend the length of the seal and to improve its reliability.
  • Such a structure is disclosed in U.S. Patent No. 4,539,511.
  • An alternative construction utilizes an arc tube without an insert.
  • a sealing button having a groove to aid in flow of the sealing material is disclosed in U.S, Patent No. 4,713,580 issued December 15, 1987 to Schoene.
  • An arc tube construction which utilizes a connection wire to position a feedthrough tube in the arc tube during sealing is disclosed in U.S. Patent No. 4,804,889 issued February 14, 1989 to Reid et al.
  • the arc lamp assembly including the electrode feedthrough having an external reservoir must have a low manufacturing cost.
  • the electrode feedthrough tube which defines the external reservoir must be hermetically sealed at its outer end and must have a passage at or near its inner end interconnecting the interior of the tube and the discharge region within the arc tube.
  • the passage must be of sufficient cross-section to permit flow of vaporized fill material, but must not be so large as to permit droplets of fill material to pass from the external reservoir into the discharge region.
  • the rod which supports the tungsten electrode must have a reliable connection, both electrically and mechanically, to the electrode feedthrough tube.
  • the external portion of the feedthrough tube must be electrically connected to the lamp frame.
  • an aperture is provided in the wall of the feedthrough tube to interconnect the interior of the tube and the discharge region.
  • An additional step is required to form the aperture.
  • the electrode feedthrough tube is flattened against the electrode support rod by mechanical deformation, leaving capillary passages between the interior of the feedthrough tube and the discharge region.
  • the disclosed configuration has four lobes in the deformed portion of the feedthrough tube.
  • a disadvantage of the disclosed configuration is that portions of the tube in the deformed region often extend beyond the outside diameter of the feedthrough, thereby making it impossible for the feedthrough tube and the electrode to be inserted through the opening in the ceramic arc tube during assembly.
  • a ceramic arc tube assembly comprising a ceramic arc tube having an opening in each end thereof, an electrode feedthrough sealed in each opening, at least one of the electrode feedthroughs comprising a conductive tube closely matched in thermal characteristics to the arc tube, the conductive tube having a first end outside the arc tube that is closed to define an interior thereof, the conductive tube and the closed first end thereof being formed in the same process without welding, crimping or fusing, and an electrode assembly coupled to a second end of the electrode feedthrough tube in an interior of the arc tube.
  • the conductive tube and the closed first end thereof are formed by deep drawing.
  • the electrode feedthrough comprises a cylindrical tube portion and a substantially hemispherical first end that is integral with the cylindrical tube portion.
  • the tube portion and the first end have a substantially uniform wall thickness.
  • the closed first end of the electrode feedthrough provides a hermetic seal.
  • an arc tube assembly comprising the steps of forming an electrode feedthrough comprising a conductive tube having a closed first end, the conductive tube and the closed first end thereof being formed in the same process without welding, crimping or fusing, attaching an electrode assembly to a second end of the electrode feedthrough, and sealing the electrode feedthrough in an opening in a ceramic arc tube with the first end positioned outside the arc tube and the electrode assembly positioned inside the arc tube.
  • the electrode feedthrough tube is preferably formed by a deep drawing process. Deep drawing of the electrode feedthrough tube provides a hermetic seal of the feedthrough without requiring an extra sealing step.
  • the electrode feedthrough is preferably a niobium tube.
  • FIG. l is a cross-sectional view of a ceramic arc tube assembly in accordance with the invention.
  • FIG. 2 shows an electrode feedthrough assembly in accordance with the present invention
  • FIG. 3 shows an alternate embodiment of an electrode feedthrough assembly in accordance with the present invention
  • FIG. 4 is an enlarged schematic illustration showing crimping of the electrode feedthrough tube to the electrode support rod.
  • FIG. 5 is a cross-sectional view of the electrode feedthrough assembly of FIG. 3.
  • FIG. 1 A cross-sectional view of an arc tube assembly in accordance with the present invention is shown in FIG. 1.
  • the arc tube assembly is typically utilized in a high pressure sodium arc discharge lamp, but may be utilized in any lamp requiring a translucent ceramic arc tube.
  • a ceramic arc tube 10 has a generally cylindrical shape and has an end member 12 or insert button sealed in each end. End member 12 may be integral with the wall of arc tube 10, may be directly sealed to arc tube 10 as disclosed in U.S. Patent No. 4,545,799 or may be sealed with an appropriate sealing frit.
  • Each end member 12 includes a centrally located opening 14 for an electrode feedthrough tube 16.
  • a sealing ring 18 is positioned over end member 12 and has an opening 20 aligned with opening 14.
  • Electrode feedthrough tube 16 extends through opening 20 in sealing ring 18 and opening 14 in. end member 12.
  • a sealing frit 22 is located in the annular region between end member 12 and feedthrough tube 16, in the annular region between sealing ring 18 and feedthrough tube 16 and between end member 12 and sealing ring 18 to provide a reliable seal of the arc tube assembly.
  • the external end of feedthrough tube 16 outside the arc tube 10 is welded to a refractory connection wire 24.
  • the internal end of feedthrough 16 inside arc tube 10 is connected to an electrode assembly 26.
  • the arc tube 10, end member 12 and sealing ring 18 are polycrystalline alumina
  • the feedthrough tube 16 is a niobium tube.
  • the niobium feedthrough tube 16 preferably contains about 1% zirconium by weight. Niobium is used because its thermal expansion characteristics closely match those of the alumina.
  • the ceramic members 10, 12 and 18 can be yttria or another suitable material.
  • the arc tube assembly contains a fill material such as a sodium mercury amalgam and a gas such as xenon. During operation, the fill material supports an arc discharge in a discharge region 28 between electrode assemblies 26.
  • the electrode feedthrough assembly includes feedthrough tube 16, connection wire 24 and electrode assembly 26.
  • the electrode assembly 26 includes an electrode coil 30 disposed on an electrode support rod 32. Typically, the electrode coil 30 and the electrode support 32 are tungsten.
  • the electrode feedthrough assembly of the present invention is designed to provide an external reservoir for the fill material which supports an arc discharge in discharge region 28 within arc tube 10.
  • the term "external reservoir” refers to an interior region 36 of feedthrough tube 16 which is partially isolated from the discharge region 28 in the ceramic arc tube 10 and is totally isolated from the ambient environment surrounding the arc tube assembly.
  • the interior of feedthrough tube 16 is connected by passages 40 and 42 to the discharge region 28 in the arc tube 10.
  • the outer end 46 of feedthrough tube 16 external to the arc tube 10 is hermetically sealed.
  • the electrode feedthrough tube 16 tends to be cooler than the discharge region 28 and the adjacent portions of arc tube 10. Therefore, any excess fill material condenses in the relatively cooler interior region 36 of feedthrough tube 16. In arc lamps not having external reservoirs, excess fill material simply condenses in the coolest portion of arc tube 10. As known in the art, the external reservoir configuration provides desirable operating characteristics.
  • the feedthrough tube 16 is a generally cylindrical, niobium tube having a length on the order of 12 mm and a wall thickness on the order of 0.25 mm. Different diameter feedthrough tubes are used, depending on the size of the arc tube.
  • the outer end 46 of feedthrough tube 16 external to arc tube 10 is hermetically sealed and typically has a generally hemispherical shape, although the shape is not critical to operation. The principal requirement is that the outer end 46 hermetically seal the feedthrough tube 16 over the life of the lamp.
  • the feedthrough tube 16 and sealed outer end 46 are formed in the same process without welding, crimping or fusing of end 46.
  • the feedthrough tube 16 is formed from a continuous piece of solid metal into a tube having one end closed. Thus, no additional steps are required to close and seal outer end 46.
  • the feedthrough tube 16 is formed by deep drawing.
  • Deep drawing is a known metal fabrication technique which is utilized to form both the cylindrical wall of feedthrough tube 16 and the closed outer end 46 in a single operation. Therefore, additional crimping, welding or fusing steps are not required to hermetically seal feedthrough tube 16.
  • the wall thickness in the outer end 46 is approximately the same as the wall thickness of the cylindrical wall. The potential for leaks is much lower for the deep drawn feedthrough tube than for tubes closed by the crimping, welding or fusing techniques of the prior art.
  • a novel crimping technique is utilized to attach the feedthrough tube 16 to electrode support rod 32.
  • the electrode feedthrough tube 16 is deformed around the support rod 32 to form a crimp 50 which retains the electrode assembly 26 and also defines passages 40 and 42 to the interior region 36 of the electrode tube 16.
  • the crimp 50 and its method of fabrication are illustrated in more detail in FIG. 4 which is an enlarged cross-sectional view of crimp 50, feedthrough tube 16 and support rod 32.
  • the crimp 50 includes first lobe portions 52 which retain the electrode support rod 32 and second lobe portions 54 which define passages 40 and 42 to the interior region 36 of the feedthrough tube 16.
  • the first lobe portions 52 substantially surround the electrode rod 32 and mechanically support it.
  • the first lobe portions 52 can be tack welded to electrode support rod 32 to further insure the integrity of the mechanical and electrical connection.
  • the second lobe portions 54 are located between electrode support rod 32 and the outside diameter of feedthrough tube 16.
  • the second lobe portion 54 can have any convenient shape but should be formed such that no portion of the crimp 50 extends beyond the outside diameter of feedthrough tube 16. This requirement insures that the electrode feedthrough assembly can be inserted through openings 14 and 20 during the fabrication process.
  • a preferred technique for forming crimp 50 is illustrated schematically in FIG. 4.
  • a first set of four crimping jaws 60, 61, 62 and 63 are used to form first lobe portions 52, and a second set* of crimping jaws 64 and 65 are used to form second lobe portions 54.
  • the crimping jaws 64 and 65 are positioned on opposite sides of the region of feedthrough tube 16 to be crimped.
  • the crimping jaws 60-63 are spaced apart between crimping jaws 64 and 65.
  • Crimping jaws 60 and 62 are positioned opposite each other, and crimping jaws 61 and 63 are positioned opposite each other.
  • the crimping jaws 60-65 are preferably equiangularly spaced around the crimp region.
  • the crimping jaws 60-63 are moved radially inward and form first lobe portions 52. Simultaneously, the crimping jaws 64 and 65 are moved inwardly and form second lobe portions 54.
  • the crimping jaws 64 and 65 are preferably shorter than the crimping jaws 60-63. As a result, the second lobe portions 54 are larger than lobe portions 52 and define passages 40 and 42. It is noted that the crimping jaws 64 and 65 are dimensioned to insure that second lobe portions 54 do not extend beyond the outside diameter of feedthrough tube 16.
  • the crimping jaws 60-65 can have a wedge shape.
  • the crimping arrangement shown and described herein meets the requirements of providing one or more passages between the interior region 36 of feedthrough tube 16 and the discharge region 28, insuring that the crimp 50 is maintained at a diameter less than -li ⁇
  • feedthrough tube 16 the diameter of feedthrough tube 16 and providing a reliable connection between feedthrough tube 16 and electrode support rod 32.
  • the crimp 50 which holds the electrode support rod 32 in place, must provide passages 40 and 42 that are sufficiently large to permit flow of gases between discharge region 28 and the interior region 36 of feedthrough tube 16.
  • the crimp would seal entirely or provide only microscopic passages.
  • the lobes of the crimp were too large to pass through the openings in the end of the arc tube.
  • the above-described technique uses four crimping jaws to form the first lobe portions 52 which retain the electrode support rod 32 and two crimping jaws shape the second lobe portions 54.
  • the crimping jaws are adjusted to maximize the passage of gases into the interior of feedthrough tube 16, while insuring that the crimp is entirely contained within the outside diameter of the feedthrough tube 16.
  • Electrode support rods of 0.047 inch, 0.0355 inch and 0.028 inch diameters were crimped onto niobium tubing of 0.156 inch outside diameter. Electrode support rods of 0.028 inch diameter were crimped onto niobium tubing of 0.085 inch outside diameter. A tack weld was formed at the interface between the niobium tube and the electrode support rod 32. By careful adjustment of the crimping jaws 64 and 65 which determine the dimension of second lobe portions 54, adequate clearance to allow the assembly to pass through the openings in the arc tube was obtained. These electrode assemblies were sealed into arc tubes. In operation of sodium mercury lamps with unsaturated vapor dosing, no problems were observed with the above-described crimp.
  • connection wire or strap 24 is a conductive element which electrically and mechanically connects feedthrough tube 16 to a frame (not shown) within the outer envelope of the arc lamp.
  • the connection wire 24 includes a circumferential portion 70 which at least partially encircles the feedthrough tube 16 and a portion 72 which extends along the conductive tube 16 in an axial direction and interconnects portion 70 to the frame.
  • the circumferential portion 70 is preferably welded to the feedthrough tube 16 at one or more points. It is preferable that the strap 24 be of the same material as the feedthrough tube 16, thereby avoiding failure of the weld caused by expansion and contraction of materials with dissimilar expansion coefficients. Thus, the strap 24 is preferably niobium.
  • the weld between the feedthrough tube 16 and the circumferential portion 70 is particularly critical relative to thermally-induced failure. The weld of the portion 72 to the frame is less failure prone because it operates at a cooler temperature.
  • FIGS. 3 and 5 Another preferred embodiment of the feedthrough assembly is shown in FIGS. 3 and 5.
  • the feedthrough tube 16, the electrode assembly 26 and the crimp 50 are constructed in the same manner shown in FIG. 2 and described hereinabove.
  • a connection wire or strap 76 includes a circumferential portion 78 which at least partially encircles the electrode feedthrough tube 16, an axial section 80 and a section 82 which interconnects circumferential portion 78 and axial section 80.
  • the axial section 80 extends from the outer end 46 of feedthrough tube 16 along the central axis of feedthrough tube 16. Since the feedthrough assembly is centrally located in arc tube 10, the axial section is located on the axis of arc tube 10.
  • the axial section 80 is used to hold the arc tube assembly together during sealing, as described hereinafter.
  • the circumferential sections 70 and 78 of straps 24 and 76 can be flattened to insure good contact with feedthrough tube 16.
  • the arc tube 10 is positioned in a vertical orientation in a furnace having the desired gas fill and pressure, with the end to be sealed in the upper position.
  • a frit ring is positioned on the end member 12, and the sealing ring 18 is positioned over the frit.
  • the electrode feedthrough assembly is inserted through the sealing ring 18 and is positioned relative to the sealing ring 18 by contact between circumferential section 70 or 78 and sealing ring 18.
  • the upper end of strap 24 or 76 presses against a solid member at the top of the furnace.
  • the lower end of the arc tube 10 rests on a spring-loaded surface.
  • the electrode feedthrough assembly is prevented from moving relative to the arc tube during sealing due to positive pressure within the arc tube 10. Such movement is a common occurrence during sealing, especially with high pressure xenon fills.
  • the strap 76 having axial section 80 is particularly advantageous in retaining the electrode feedthrough assembly in position during sealing since the axial section 80 is on the central axis of the arc tube assembly, and tipping is avoided.
  • Electrode assemblies have been constructed using 0.030 inch diameter niobium wire, with niobium tubing of 0.156 inch and 0.085 inch diameter having one end closed.
  • niobium tubing of 0.156 inch and 0.085 inch diameter having one end closed.
  • Electrical resistance welding cannot readily be used due to the pressure exerted and the possibility of distorting the niobium tube.
  • Laser welding has been found to be successful. Care must be taken to avoid puncturing the niobium tube with the laser.
  • One way to improve reliability is to flatten the wire.
  • the 0.030 inch diameter round wire is flattened to dimensions of 0.015 by 0.043 inch.
  • the wider dimension is in contact with the outside surface of the niobium feedthrough tube, thereby providing a larger target for the laser weld and requiring less energy to form the weld.
  • the above-described technique has been utilized without difficulty with 0.085 inch diameter niobium tubing in 70 and 100 watt high pressure sodium lamps and with 0.156 inch outer diameter niobium tubing in 400 watt high pressure sodium lamps.
  • Two welds along the circumferential section of the strap, one near the part which extends along the axis of the tube and one at the opposite end provide good rigidity during sealing.
  • the electrode feedthrough assembly of the present invention 400 watt unsaturated vapor lamps utilizing arc tubes with insert buttons were tested.
  • the arc tubes were 10.2 millimeters outside diameter and 108 millimeters cavity length.
  • An opening of about 0.160 inch is provided in the insert button.
  • the button opening accommodated niobium tubing of 0.156 outside diameter.
  • the sealing ring was 3 millimeters thick and had an opening of 0.160 inch.
  • the lamps contained various electrode geometries with a fill material of 3 milligrams, 3.4% by weight sodium in a sodium-mercury amalgam. Ten such lamps have been on test for 4000 hours without any failures.
  • the present invention is not limited to the arc tube construction shown in FIG. 1.
  • the sealing ring 18 can be omitted.
  • a grooved arc tube sealing button can be utilized as disclosed in U.S. Patent No. 4,713,580.
  • the electrode feedthrough assembly of the present invention can be utilized either at one end or at both ends of the arc tube assembly. When only one of the above described electrode feedthrough assemblies is utilized, a conventional feedthrough assembly is utilized at the opposite end of the arc tube assembly.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Vessels And Coating Films For Discharge Lamps (AREA)

Abstract

Un ensemble de réception d'électrodes dans un tube à régime d'arc en céramique du type utilisé dans des lampes à arc en sodium sous haute pression est particulièrement utile dans un tube à régime d'arc à réservoir extérieur dans lequel une zone intérieure du tube de réception est utilisée comme réservoir pour le matériau de remplissage de la lampe. L'ensemble de réception d'électrodes comprend un tube de réception (16) et un fil de connexion (76). Le tube de réception a une extrémité fermée (46) extérieure au tube à régime d'arc. Le tube de réception (16) et son extrémité fermée (46) sont formés en une seule operation, de préférence par emboutissage profond, sans soudures, sans sertissages ou sans fusion. On ménage des passages jusqu'à l'intérieur du tube de réception en sertissant la tige de support de l'électrode sur le tube de réception au moyen d'un agencement de sertissage à six mâchoires dont deux mâchoires de sertissage (64, 65) sont plus courtes que les quatre autres mâchoires (60-63). Le fil de connexion (76) est attaché au tube de réception (16) et comprend une partie (80) située sur l'axe du tube (16). Le fil de connexion (76) aide à retenir l'ensemble de réception de l'électrode dans le tube régime d'arc (10) pendant son scellement.
PCT/US1990/007404 1989-12-14 1990-12-13 Tube de reception d'electrodes pour lampes a decharge en arc WO1991009417A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US45064489A 1989-12-14 1989-12-14
US450,644 1989-12-14

Publications (1)

Publication Number Publication Date
WO1991009417A1 true WO1991009417A1 (fr) 1991-06-27

Family

ID=23788928

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1990/007404 WO1991009417A1 (fr) 1989-12-14 1990-12-13 Tube de reception d'electrodes pour lampes a decharge en arc

Country Status (1)

Country Link
WO (1) WO1991009417A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3821587A (en) * 1973-03-08 1974-06-28 Westinghouse Electric Corp Ceramic discharge lamp operable in air without an outer glass envelope
JPS5457376A (en) * 1977-10-17 1979-05-09 Hitachi Ltd High-pressure metal vapor discharge lamp
JPS5758936A (en) * 1980-09-24 1982-04-09 Sumitomo Metal Ind Ltd Manufacture of seamless eccentric reducer tube joint
FR2509091A1 (fr) * 1981-07-01 1983-01-07 Sefli Electrode a cathode froide, notamment pour tubes fluorescents, et procede de realisation d'une telle electrode

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3821587A (en) * 1973-03-08 1974-06-28 Westinghouse Electric Corp Ceramic discharge lamp operable in air without an outer glass envelope
JPS5457376A (en) * 1977-10-17 1979-05-09 Hitachi Ltd High-pressure metal vapor discharge lamp
JPS5758936A (en) * 1980-09-24 1982-04-09 Sumitomo Metal Ind Ltd Manufacture of seamless eccentric reducer tube joint
FR2509091A1 (fr) * 1981-07-01 1983-01-07 Sefli Electrode a cathode froide, notamment pour tubes fluorescents, et procede de realisation d'une telle electrode

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 3, no. 80 (M-65) 11 July 1979, & JP-A-54 57376 (HITACHI SEISAKUSHO K.K.) 9 May 1979, see the whole document *
PATENT ABSTRACTS OF JAPAN vol. 6, no. 134 (M-144) 21 July 1982, & JP-A-57 58936 (SUMITOMO METAL IND LTD ET AL.) 9 April 1982, see the whole document *

Similar Documents

Publication Publication Date Title
EP0074720B1 (fr) Lampe à décharge
EP0751549B1 (fr) Lampe a decharge haute pression et procede de production correspondant
JPH1173919A (ja) セラミック放電管を有するメタルハライドランプ
JP2002304969A (ja) シュラウド付きの電球
US4160930A (en) Electric discharge lamp with annular current conductor
US5343117A (en) Electrode feedthrough connection strap for arc discharge lamp
EP0645800B1 (fr) Lampe à décharge haute pression
US4804889A (en) Electrode feedthrough assembly for arc discharge lamp
US6856091B2 (en) Seal for ceramic metal halide discharge lamp chamber
US4318024A (en) Flash tube
US4707636A (en) High pressure sodium vapor lamp with PCA arc tube and end closures
WO1991009416A1 (fr) Jonction par sertissage de l'electrode au tube de traversee dans une lampe a decharge en arc
US6169366B1 (en) High pressure discharge lamp
GB2366908A (en) Metal halide lamp with ceramic discharge vessel
US6856079B1 (en) Ceramic discharge lamp arc tube seal
GB2072939A (en) Metal vapour discharge lamp
KR20070046186A (ko) 램프
WO1991009417A1 (fr) Tube de reception d'electrodes pour lampes a decharge en arc
JP2006019303A (ja) メタルハライドランプ
JP3627367B2 (ja) セラミック放電灯
US7619350B2 (en) Arc discharge vessel having arc centering structure and lamp containing same
JP3627370B2 (ja) セラミック放電灯
EP0807956B1 (fr) Arrangement d'électrode pour lampe au sodium haute pression et son procédé de fabrication
EP1146537B1 (fr) Tube a arc de lampe a decharge haute pression et son procede de fabrication
US4853596A (en) Flash discharge lamp with sintered cathode member

Legal Events

Date Code Title Description
AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU NL SE