EP0599581B1 - Zündungsquelle und Herstellungsverfahren derselben - Google Patents

Zündungsquelle und Herstellungsverfahren derselben Download PDF

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Publication number
EP0599581B1
EP0599581B1 EP19930309292 EP93309292A EP0599581B1 EP 0599581 B1 EP0599581 B1 EP 0599581B1 EP 19930309292 EP19930309292 EP 19930309292 EP 93309292 A EP93309292 A EP 93309292A EP 0599581 B1 EP0599581 B1 EP 0599581B1
Authority
EP
European Patent Office
Prior art keywords
tube
seal
ribbon
starting source
envelope
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
EP19930309292
Other languages
English (en)
French (fr)
Other versions
EP0599581A1 (de
Inventor
Gregory Zaslavsky
Edward H. Nortrup
Joseph V. Lima
Richard A. Parrott
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Flowil International Lighting Holding BV
Original Assignee
Flowil International Lighting Holding BV
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
Priority claimed from US07/979,140 external-priority patent/US5323087A/en
Priority claimed from US07/982,209 external-priority patent/US5248273A/en
Application filed by Flowil International Lighting Holding BV filed Critical Flowil International Lighting Holding BV
Publication of EP0599581A1 publication Critical patent/EP0599581A1/de
Application granted granted Critical
Publication of EP0599581B1 publication Critical patent/EP0599581B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00Apparatus 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
    • H01J9/24Manufacture or joining of vessels, leading-in conductors or bases
    • H01J9/32Sealing leading-in conductors
    • H01J9/323Sealing leading-in conductors into a discharge lamp or a gas-filled discharge device
    • H01J9/326Sealing leading-in conductors into a discharge lamp or a gas-filled discharge device making pinched-stem or analogous seals
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00Gas-discharge or vapour-discharge lamps
    • H01J61/02Details
    • H01J61/36Seals between parts of vessels; Seals for leading-in conductors; Leading-in conductors
    • H01J61/366Seals for leading-in conductors
    • H01J61/368Pinched seals or analogous seals
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00Gas-discharge or vapour-discharge lamps
    • H01J61/02Details
    • H01J61/54Igniting arrangements, e.g. promoting ionisation for starting

Definitions

  • This invention relates to a starting source for an arc discharge lamp, and to a method of manufacture thereof.
  • High pressure metal halide arc discharge lamps typically comprise an arc tube which encloses an ionisable fill material and two electrodes at opposing ends of the tube.
  • a starter electrode may be disposed inside the arc tube near one of the main electrodes, as shown in US-A-3,900,761.
  • a discharge can be initiated between the starter electrode and one of the main electrodes at a voltage that is much lower than the voltage required to ignite an arc between the two main electrodes.
  • the ultraviolet radiation and plasma from this discharge enhance discharge formation in the arc tube between the two main electrodes.
  • US-A-4,818,915 discloses a starting source which is separate from the arc tube and that typically has a borosilicate glass envelope enclosing an ionizable fill material and a single electrode.
  • the single electrode additionally has a getter which removes certain gases when the envelope heats and outgasses. These gases, particularly oxygen, hydrogen, and nitrogen, contaminate the fill material.
  • the starting source When energized, the starting source produces ultraviolet radiation which illuminates the path between the main electrodes within the arc tube, thus decreasing the time for generating a high intensity arc discharge.
  • a getter increases the number of components in the starting source, limits how small the starting source can be made, and limits the operation of the starting source to a particular temperature range.
  • the starting source is sensitive to location within the lamp because of outgassing and the getter temperature range. Because of these size and location requirements, a starting source with a getter cannot be used for all applications, such as double-ended lamps which have a small diameter outer envelope.
  • a typical process for making a starting source begins with fabricating an electrode assembly which is inserted into a tube.
  • the electrode assembly typically has a number of welded parts.
  • an electrode assembly includes an electrode which is welded to a lead for coupling electrical energy and which may additionally support a getter. Since the parts are welded, it can be difficult to produce these starting sources with an automated system. Electrode assemblies are fabricated first, then manually loaded onto trays.
  • a starting source for an arc discharge lamp comprising an envelope having a seal and an interior region which contains a fill material for supporting an ultraviolet emitting discharge, an electrode in the interior region and a lead for carrying electrical energy to the electrode, characterised in that the electrode comprises a conductive ribbon which extends from the seal into the interior region of the envelope.
  • a method of making a starting source for an arc discharge lamp comprising the steps of forming an envelope having an interior region, providing an electrode in the interior region, providing a lead for carrying electrical energy to the electrode, providing a fill material in the interior region for supporting an ultraviolet emitting discharge, and closing the envelope with a seal, characterised in that the electrode comprises a conductive ribbon which extends from the seal into the interior region of the envelope.
  • Preferred embodiments of the present invention may provide a starting source for an arc discharge lamp which comprises a sealed ultraviolet transmissive envelope enclosing a fill material which supports an ultraviolet emitting discharge.
  • the sealed envelope has a seal and an interior region.
  • a conductive ribbon extends from the press seal into the interior region of the envelope.
  • a wire lead carries electrical energy to the conductive ribbon.
  • the fill material comprises argon
  • the conductive ribbon comprises molybdenum
  • the seal forming steps each comprise forming a press seal. They may also comprise the steps of obtaining a remaining portion of the tube after the second seal has been formed and after the sealed envelope is removed, introducing a molybdenum ribbon and a wire lead into an open end of the remaining portion, and forming a seal at the open end to form a second sealed envelope.
  • the present invention may provide a metal vapour arc discharge lamp comprising a sealed arc tube which encloses a first fill material and two electrodes; an ultraviolet radiation starting source comprising an ultraviolet-transmissive sealed envelope, a second fill material within the sealed envelope, a molybdenum ribbon extending from a seal into the interior region of the sealed envelope, and a wire lead for carrying electrical energy to the ribbon; an outer light-transmissive envelope enclosing the arc tube and the UV source; and a means for coupling electrical energy to the two electrodes of the arc tube and to the UV source.
  • the ribbon and the wire lead may each be mounted on a spool and inserted into the tube by rotating each spool by a predetermined amount. After the seal is formed, the ribbon and wire are cut external to the tube.
  • the method may further comprise vacuum pumping to create a desired pressure and forming a second seal at a second end of the tube to form a sealed envelope. After formation of a seal, the ribbon and the wire lead are in non-bonded contact with each other over a portion of the length of the ribbon.
  • the present invention provides a method for making a starting source for an arc discharge lamp that comprises the steps of providing an ultraviolettransmissive tube having an opening, inserting a conductive ribbon and wire lead into the opening, the ribbon and the wire lead not being attached to each other prior to formation of a seal at or near the opening in the tube, and forming a seal at or near the opening of the tube such that the tube material urges the ribbon and the wire lead together into electrical connection.
  • Further preferred methods of the present invention provide a system for producing a starting source in which the ribbon and the wire lead may be inserted into the tube without welding or other bonding, thus, eliminating electrode preassembly.
  • the ribbon and the wire lead can be fed manually or automatically. Such a method makes it easier to produce starting sources with an automated system.
  • a prior art metal halide arc discharge lamp 10 is shown in Fig. 1.
  • a sealed envelope 12 encloses a cylindrical quartz sleeve 14.
  • the sleeve 14 surrounds an arc tube 16 which encloses two electrodes 18 located at opposite ends of the arc tube and a fill material, e.g., a combination of mercury, metal halides, and argon.
  • Each electrode is coupled to a molybdenum ribbon 20 which is enclosed within a seal 22 that hermetically seals the arc tube.
  • Electrical energy is coupled from a lamp base 28 through a lamp stem 30 and leads 32 and 26 to the electrodes 18 in the arc tube 16.
  • a starting source 24 has a sealed envelope 34 that encloses an electrode 25.
  • the electrode 25 is coupled to the lead 26, and is capacitively coupled to the lead 32 which may include a conductor that is helically wrapped around the envelope 34.
  • a typical starting source is about 4.0 mm in diameter and 15.0 to 20.0 mm in overall length. Other details relating to the prior art starting source 24 are discussed in US-A-4,818,915.
  • Figs. 2(a)-2(d) represent the steps to produce a starting source according to a preferred embodiment of the present invention.
  • a molybdenum ribbon 40 and a nickel wire 42 are positioned at a lower end 46 of a cylindrical quartz tube 44.
  • the ribbon and wire are placed together, without being bonded to each other, and are inserted into the lower end 46 of tube 44.
  • the ribbon 40 extends further into the interior of the tube 44 than the wire 42, as shown in Fig. 2(b).
  • the ribbon 40 has sharp edges which are produced by rollers. These edges provide high electric field concentration, which results in reliable breakdown.
  • a fill material such as argon
  • a seal 50 may be formed in the lower portion of the tube 44 by heating the tube and pressing the lower end together (Fig. 2(c)), a technique well known in the art.
  • a vacuum system 56 coupled to the tube at upper end 48 is a vacuum system 56 which reduces the pressure in the tube down to a desired level, such as 666-2666 Pa (5-20 Torr).
  • the vacuum system 56 may be coupled to the tube after the first seal is pressed, or it may be coupled during the entire process and activated only when needed to reduce pressure.
  • a second seal 58 (shown as part of the remaining tube in Fig. 2(d)) is formed at the upper end of tube 44.
  • the resulting starting source 60 comprises a sealed envelope 62 which encloses a fill material 64, typically argon, and a strip 66 of molybdenum ribbon which is hermetically sealed within the envelope 62.
  • the wire 42 is located in a portion of the seal area so as to maintain electrical contact with the ribbon 40, but is outside the interior of the sealed envelope 62.
  • a second seal 72 closes one end of a remaining portion 70 of tube 44.
  • a second molybdenum ribbon 76, and a wire 78 are positioned at an open end 80 of a dome 74, which corresponds to remaining portion 70.
  • the vacuum system is temporarily removed, and the ribbon and wire are positioned in the interior 82 of dome 74.
  • the vacuum system 56 reduces the pressure within dome 74 (Fig. 3(b)), and seal 84 is formed at the lower end of the dome (Fig. 3(c)). This process results in a second starting source similar to starting source 60.
  • an automatic feeding system 90 includes molybdenum ribbon spool 92 and wire spool 94. These spools hold lengths of ribbon 96 and wire 98, and feed predetermined lengths them together into quartz tube 100 when they are rotated a desired amount.
  • the quartz tube 100 may be positioned with its upper end in an exhaust tube 102 (part of the vacuum system). Adjacent to a lower end of the tube are press feet 104 which can form a seal. In operation, the spools feed the ribbon and wire into the tube, press feet 104 form a seal as represented in Figs. 2(c) and 3(c), and the ribbon and wire are cut below the seal.
  • the interior of the tube 100 is then pumped, and a seal is formed at the upper end to finish the starting source.
  • the ribbon and the wire are unattached prior to formation of a seal.
  • the tube material may urge the wire and the ribbon into contact, thereby forming a reliable electrical connection without requiring welding or other bonding techniques.
  • Another tube is loaded into exhaust tube 102 and the procedure is repeated.
  • the wire and ribbon are fed without using adhesives or other bonding techniques, such as welding or soldering.
  • the resulting starting sources have been produced with dimensions of about 2.5 mm in diameter and about 10.0 mm long.
  • the molybdenum ribbon is preferably about 0.02 mm to 0.03 mm thick, 1.0 mm wide, and about 4.0 to 7.0 mm long, of which about 2.0 mm to 3.0 mm is within the envelope.
  • the wire has been described as nickel, but other conductors, such as tungsten or molybdenum may be used, depending on the temperature of the starter electrode and the lamp.
  • the fill material may be substantially only argon, or may include other materials, such as mercury.
  • the tube may be quartz, Vycor, or some other high temperature alumina silicate glass.
  • a starting source of the present invention may be relatively inexpensive and easy to produce compared to prior art starting sources.
  • the conductive ribbon is used in the seal to create a hermetic seal, and as an electrode.
  • the source may be produced so that the only materials within the envelope are the gaseous fill material and the molybdenum ribbon. Fewer parts are necessary, no getter is used, no mercury is needed, and the starting source can be made smaller than prior art devices.
  • Embodiments of the present invention should provide a simplified method for fabricating a starting source which has fewer components than prior art devices, and which may operate under a broad range of conditions.

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

Claims (12)

  1. Zündquelle für eine Bogenentladungslampe, die eine Hülle (44; 74; 100) mit einer Dichtung (50; 84) und einen Innenbereich umfaßt, der ein Füllmaterial zum Unterstützen einer ultraviolettemittierenden Entladung, eine Elektrode (66; 76; 96) im Innenbereich und eine Zuleitung (42; 78; 98) zum Zuführen von elektrischer Energie zu der Elektrode enthält,
    dadurch gekennzeichnet, daß die Elektrode ein leitendes Band (40, 66; 76; 96) umfaßt, das sich von der Dichtung (50; 84) in den Innenbereich der Hülle (44; 74; 100) erstreckt.
  2. Zündquelle nach Anspruch 1,
    dadurch gekennzeichnet, daß das Band (40, 66; 76; 96) Molybdän enthält.
  3. Zündquelle nach Anspruch 1 oder 2,
    dadurch gekennzeichnet, daß das Füllmaterial Argon enthält.
  4. Zündquelle nach Anspruch 1, 2 oder 3,
    dadurch gekennzeichnet, daß der Innenbereich nicht mit einem Getter versehen ist.
  5. Zündquelle nach einem der vorhergehenden Ansprüche,
    dadurch gekennzeichnet, daß die Zuleitung (42; 78) im Bereich der Dichtung (50; 84) in elektrischem Kontakt gegen das Band (40, 66; 76) gehalten ist.
  6. Zündquelle nach Anspruch 5,
    dadurch gekennzeichnet, daß sich die Zuleitung (42; 78) nicht in den Innenbereich erstreckt.
  7. Bogenentladungslampe,
    dadurch gekennzeichnet, daß sie mit einer Zündquelle nach einem der vorhergehenden Ansprüche versehen ist.
  8. Verfahren zur Herstellung einer Zündquelle für eine Bogenentladungslampe, das folgende Schritte umfaßt: Bilden einer Hülle (44; 74; 100) mit einem Innenbereich, Vorsehen einer Elektrode (66; 76; 96) in dem Innenbereich, Vorsehen einer Zuleitung (42; 78; 98) zum Zuführen von elektrischer Energie zur Elektrode, Vorsehen eines Füllmaterials in dem Innenbereich zum Unterstützen einer ultraviolettemittierenden Entladung, und Abschließen der Hülle mit einer Dichtung (50; 84),
    dadurch gekennzeichnet, daß die Elektrode (66; 76; 96) ein leitendes Band umfaßt, das sich von der Dichtung (50; 84) in den Innenbereich der Hülle (44; 74; 100) erstreckt.
  9. Verfahren nach Anspruch 8,
    dadurch gekennzeichnet, daß das Band (40, 66; 76; 96) und die Zuleitung in Kontakt miteinander versetzt werden und die Dichtung (50; 84) um sie herum ausgebildet wird, so daß sie eine elektrische Verbindung bilden.
  10. Verfahren nach Anspruch 8 oder 9,
    dadurch gekennzeichnet, daß das Band (40, 66; 76; 96) und die Zuleitung (42; 78; 98) separat als Längen zugeführt werden, die in gewünschte Abschnitte geschnitten werden.
  11. Verfahren nach Anspruch 8, 9 oder 10,
    gekennzeichnet durch die folgenden Schritte: Vorsehen einer Röhre (44; 100) zum Bilden der Hülle, Hindurchführen des Füllmaterials durch eine Röhre, Einsetzen des Bandes (40, 66; 76; 96) und der Zuleitung (42; 78; 98) in die Röhre an einem Ende, Bilden der Dichtung (50; 84) an dem einen Ende und um das Band und die Zuführung, Abpumpen am anderen Ende (48) der Röhre (44; 100), um einen gewünschten Druck innerhalb der Röhre zu erzeugen, und Bilden einer zweiten Dichtung (58) an dem Röhrenende (62).
  12. Verfahren nach Anspruch 11,
    dadurch gekennzeichnet, daß die Hülle, nachdem die zweite Dichtung gebildet wurde, entfernt wird und ein verbleibender Abschnitt (70) der Röhre (44; 100) dazu verwendet wird, eine weitere Zündquelle herzustellen.
EP19930309292 1992-11-20 1993-11-22 Zündungsquelle und Herstellungsverfahren derselben Expired - Lifetime EP0599581B1 (de)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US979140 1992-11-20
US07/979,140 US5323087A (en) 1992-11-20 1992-11-20 Ultraviolet radiation starting source and lamp containing same
US07/982,209 US5248273A (en) 1992-11-25 1992-11-25 Method of fabricating ultraviolet radiation starting source
US982209 2001-10-17

Publications (2)

Publication Number Publication Date
EP0599581A1 EP0599581A1 (de) 1994-06-01
EP0599581B1 true EP0599581B1 (de) 1996-04-24

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Application Number Title Priority Date Filing Date
EP19930309292 Expired - Lifetime EP0599581B1 (de) 1992-11-20 1993-11-22 Zündungsquelle und Herstellungsverfahren derselben

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EP (1) EP0599581B1 (de)
DE (1) DE69302357T2 (de)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3394645B2 (ja) * 1996-03-12 2003-04-07 株式会社小糸製作所 アークチューブおよびその製造方法
US9368338B2 (en) * 2011-06-16 2016-06-14 Mocon, Inc. Gas discharge lamp with an axially extending strip of getter and method of manufacture
USD797984S1 (en) 2016-03-24 2017-09-19 Mocon, Inc. UV lamp

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4818915A (en) * 1987-10-22 1989-04-04 Gte Products Corporation Arc discharge lamp with ultraviolet radiation starting source
US5248273A (en) * 1992-11-25 1993-09-28 Gte Products Corporation Method of fabricating ultraviolet radiation starting source

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DE69302357T2 (de) 1996-12-05
EP0599581A1 (de) 1994-06-01
DE69302357D1 (de) 1996-05-30

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