EP0591777A2 - Méthode de fabrication d'une lampe à décharge à haute pression de faible puissance à pincement unique et lampes à décharge à haute pression - Google Patents

Méthode de fabrication d'une lampe à décharge à haute pression de faible puissance à pincement unique et lampes à décharge à haute pression Download PDF

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Publication number
EP0591777A2
EP0591777A2 EP93115390A EP93115390A EP0591777A2 EP 0591777 A2 EP0591777 A2 EP 0591777A2 EP 93115390 A EP93115390 A EP 93115390A EP 93115390 A EP93115390 A EP 93115390A EP 0591777 A2 EP0591777 A2 EP 0591777A2
Authority
EP
European Patent Office
Prior art keywords
discharge
discharge volume
pinch
electrode
volume
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.)
Withdrawn
Application number
EP93115390A
Other languages
German (de)
English (en)
Other versions
EP0591777A3 (fr
Inventor
Achim Gosslar
Ulrich Dr. Henger
Jürgen Dr. Heider
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.)
Osram GmbH
Original Assignee
Patent Treuhand Gesellschaft fuer Elektrische Gluehlampen mbH
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 Patent Treuhand Gesellschaft fuer Elektrische Gluehlampen mbH filed Critical Patent Treuhand Gesellschaft fuer Elektrische Gluehlampen mbH
Publication of EP0591777A2 publication Critical patent/EP0591777A2/fr
Publication of EP0591777A3 publication Critical patent/EP0591777A3/fr
Withdrawn legal-status Critical Current

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Classifications

    • 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
    • H01J61/366—Seals for leading-in conductors
    • H01J61/368—Pinched seals 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
    • H01J61/04—Electrodes; Screens; Shields
    • H01J61/06—Main electrodes
    • H01J61/073—Main electrodes for high-pressure discharge lamps
    • H01J61/0732—Main electrodes for high-pressure discharge lamps characterised by the construction of the electrode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00—Gas-discharge or vapour-discharge lamps
    • H01J61/02—Details
    • H01J61/30—Vessels; Containers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00—Gas-discharge or vapour-discharge lamps
    • H01J61/82—Lamps with high-pressure unconstricted discharge having a cold pressure > 400 Torr
    • 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
    • H01J9/245—Manufacture or joining of vessels, leading-in conductors or bases specially adapted for gas discharge tubes or lamps
    • H01J9/247—Manufacture or joining of vessels, leading-in conductors or bases specially adapted for gas discharge tubes or lamps specially adapted for gas-discharge lamps

Definitions

  • the invention relates both to a method for producing high-pressure discharge lamps of small wattage that are squeezed on one side, and to such lamps themselves.
  • Typical wattages of these lamps are between 35 and 150 W.
  • the actual quartz glass discharge vessel is still surrounded by an outer bulb.
  • the discharge vessel in which two angled electrodes are arranged, encloses an ionizing filling, which usually contains ignition gas, metal vapors and metal halides.
  • the area of application of these lamps is primarily interior and shop window lighting, because they are characterized by high luminous efficacy and good color rendering. These lamps are described for example in DE-OS 32 32 207 and 38 42 483.
  • EP-A 369 370 it is proposed in EP-A 369 370 to dispense with a pump tube and instead to seal a tube end on one side by means of a form roller, then to precisely define the final shape of the future lamp vessel by means of blow molding and then after rinsing and filling through the still open one second pipe end to seal this with a pinch.
  • This process has two disadvantages: the filling is already in the discharge volume during the preparatory heating and the actual crushing process and therefore has to be cooled in a complex manner; secondly, the precisely pre-shaped volume is deformed again during the squeezing process.
  • the sealing and the final shape of the discharge vessel are made in one Work step carried out.
  • This is advantageously done by squeezing the tube piece equipped with a pump tube with four crimping jaws (two main and two side crimping jaws), wherein at the same time the shaping jaws which determine the shape of the discharge vessel comprise the tube section which is to form the future discharge volume.
  • An inert gas (nitrogen or argon) with excess pressure is introduced into the future discharge volume via the pump tube.
  • the four crimping jaws are each advantageously equipped with a shaping attachment (extension part), so that separate molding jaws can be dispensed with.
  • the discharge volume can thus be reproduced particularly well. The volume fluctuations are reduced from around 7% to 4% now.
  • a very special advantage of this method is that the simultaneous creation of squeeze and discharge volume, the intermediate transition area can be designed in an ideal manner by the side squeeze jaws have obliquely projecting ramps that shape the transition area so that a defined slope between the Wall of the discharge volume and the narrow sides of the bruise, which is arranged substantially below the discharge volume. In this way, disruptive "pockets" are eliminated, which would form due to the lateral action of the side crushing jaws without this trick in the transition area between the discharge volume and the crushing during the crushing process.
  • the bevels presented here are also to be clearly distinguished from the bevels described in DE-OS 38 42 483 for metal vapor lamps pinched on one side. These are positioned slightly below the electrodes next to the discharge volume and are also intended to increase the "cold spot” temperature behind the electrodes. They have no function during manufacture. They therefore do not serve to improve the burst protection by avoiding "pockets” below the discharge volume. Such "pockets” could not even occur in this prior art because the discharge vessel was obviously closed with only two pinch jaws, which can be concluded from the width of the pinch, which is significantly greater than the discharge volume.
  • the slope according to the invention is particularly advantageously inclined at approximately 20-30 ° against the narrow side, since the formation of the "pockets" is then most reliably avoided.
  • the main crimping jaws have side bevels which interact with the obliquely projecting ramps of the side crimping jaws by increasing their inclination, in particular by 15-30%, so that the quartz flow from Discharge volume is directed away.
  • the method according to the invention can be modified in such a way that, in order to increase the machine output, the tube piece is first roughly pre-shaped before closing and at the same time final forms. This is done by approximating a part or almost the entire pipe to the desired final shape.
  • the open end of the tube is deformed by compression molding so that it has an oval cross section.
  • Various techniques are described in DE-OS 35 37 880, 35 37 879 and 35 37 878.
  • This in particular facilitates the insertion of the electrode system and thus prevents the foils or electrodes from accidentally sticking to the glass wall during insertion.
  • Another or additional possibility is to preform the area of the future discharge volume by heating this area and then - with the open tube end being closed - by blow molding to approximate the future shape.
  • the area of the future discharge volume close to the pump tube which is only insufficiently captured during final shaping, can be precisely shaped.
  • preforming by means of shaping rolls in this area also meets the requirements.
  • the preforming of the future crushing area in particular by compression molding, has the particular advantage in the present case that it facilitates the safe insertion of electrode systems whose straight electrode shafts are slightly (approx. 5 °) inclined outwards with respect to the optical axis.
  • the use of such electrode systems is not restricted to this special production method.
  • a lamp with such inclined electrodes has the advantage, regardless of the manufacturing process, that the electrode spacing is increased. As a result, a higher operating voltage is achieved, so that the operating pressure can be reduced. Ultimately, this measure also improves the burst protection.
  • the 35 W high-pressure discharge lamp 1 shown in FIG. 1 consists of a discharge vessel 2 made of quartz glass, squeezed on one side, with an ellipsoidal (or also spherical or barrel-shaped) discharge volume 3, which is arranged in particular in an outer bulb (not shown).
  • a pump connection 5 is arranged on the side of the volume 3 opposite the pinch 4.
  • the electrodes consist of straight shafts 6, to which tips 7 bent approximately at right angles are attached, the shafts 6 being inclined outward about 5 ° with respect to the optical axis A and the tip 7 being able to be coiled or spherical. They are melted into the pinch 4 by means of molybdenum foils 8.
  • the power supply lines 10 connected to the foils 8 Molybdenum also serve as a holder for the discharge vessel 2 in the outer bulb.
  • the discharge vessel 2 has an internal volume 3 of 0.11 cm 3.
  • the filling is composed, for example, of NaJ, SnJ2, TlJ and Hg, and argon is used as the ignition gas.
  • the ellipsoidal discharge volume 3 which is surrounded by a 1.3 mm thick wall 11, is in a very good approximation (due to the blow molding) due to a large semi-axis of approximately 9.0 mm overall length and two perpendicular to the connecting line of the electrode tips 7 small semiaxes with a total length of 4.8 mm each are characterized.
  • the operating pressure is around 35 - 40 bar.
  • This low pressure (approx. 80% of the usual value) results from the relatively large electrode spacing of 5.2 mm (previously approximately 4.5 mm), which is achieved in that the straight electrode shafts 6 (diameter 0.3 mm) face each other the optical axis A are inclined outwards by approximately 5 °.
  • the current flowing through the shafts 6 is approximately 0.5 A. Since there is a risk of an arc discharge between the shafts 6 at the point at which they emerge from the wall 11 in such an arrangement during ignition, it is expedient to use the shafts 6 with a sleeve 12 made of insulating material (eg ceramic or quartz glass).
  • the cross section of the pinch seal 4 which seals the discharge volume 3 has the double T shape which is known per se (ie, two “T” abut one another at the base). With a length of 35 mm, it has a width of approximately 11 mm on the broad sides 13 of the pinch, which corresponds approximately to the maximum width of the discharge vessel 2. On the narrow sides 14, the width, including that which determines the double T shape, is Bead 15 about 5 mm. The narrow sides 14 are each connected to their starting point 16 on the wall of the discharge volume via a bevel 17.
  • the outer surface (or, in a side view, the outer edge) 18 of the bevel is inclined by approximately 26 ° to the optical axis A, whereas the inner edge 19 of the bevel, which is produced by the bead 15, is only inclined by approximately 20 ° to the axis A, so that the bead 15 tapers towards the starting point 16.
  • the bevels 17 start at approximately the level of the lower edge of the discharge volume 3 facing the pinch 4.
  • lamps of similar design have a power of 150 W or 70 W.
  • the inside diameter of the discharge volume is 0.82 cm3 or 0.28 cm3 at an operating pressure of 25-30 bar or 35-40 bar.
  • the ellipsoid forming the discharge volume has a large semiaxis of 15.0 and 10.8 mm and small semiaxes of 10.2 and 7.0 mm, respectively.
  • the lamp current is 1.8 A or 0.9 A with a diameter of the electrode shaft of 0.5 mm or 0.4 mm.
  • a tube section 20 made of quartz glass is inserted into a rotating receptacle (arrow B) and heated in the center by means of a gas burner 21 (FIG. 2a) until it can be pulled apart (arrows C1, C2), so that two tube sections 20a, 20b are formed between which a central portion 22 of smaller diameter is arranged over tapered portions 23, the central section 22 later forming the two pump tubes (FIG. 2b).
  • the area of the taper 23 between a pipe section, for example 20a, and the associated pump tube 22 ' is heated with a gas burner 21' and shaped like a dome by means of a rotating shaping roller 24, the part being desired at this point Radius of the future discharge volume is adjusted.
  • the parameters determining this radius are the width of the heating zone and the shape of the shaping roller 24 (FIG. 2c).
  • the open end region 25 of the pipe section 20a is moderately heated and deformed by mold jaws 26 so that it has an oval cross section (FIG. 2d).
  • the mold jaws 26 are advantageously so wide (26a) that part of the future discharge volume 3 'is roughly preformed.
  • the interchangeable receptacle 27 is provided on its outer surface with resilient element 27a known to the person skilled in the art (preferably three elements; only one is visible in FIG. 2e). These are quasi supported on the inner wall of the tube piece 20a and thereby hold the interchangeable holder 27 by themselves.
  • the defined position of the electrode systems 28 within the future lamp vessel is achieved by lowering a punch 27b, which is connected to the exchangeable receptacle via an arm 27c, to a stop (schematically shown) for inserting the exchangeable receptacle 27 into the tube piece 20a.
  • This process is also known to the person skilled in the art and is therefore not shown separately (FIG. 2e).
  • a crimping machine 29 (FIG. 3) with two main crimping jaws 30 (one is partially removed in FIG. 3a) and two side crimping jaws 31 now seals the open pipe end by means of a double-T-shaped crimp.
  • the crimping jaws 30, 31 advantageously have extension pieces 33a, 33b attached to the actual crimping surfaces 32a, 32b. These have concave troughs 34a, 34b (indicated by dashed lines) on their broad sides facing the pipe section, which in the closed, ie, squeezing, state of the squeezing machine 29 almost fit together and define the shape of the discharge volume.
  • the pumping tube 22 'N 2 or another inert gas is introduced into the future discharge volume under slight overpressure and the discharge volume 3 is thus formed in the region of the extension pieces 33a, 33b.
  • ramps 35 which form the transition area between the squeeze surfaces 32b and the extension pieces 33b, produce the bevels 17 on the narrow sides of the squeeze (FIG. 1) on the two side squeeze jaws 31 (FIG. 3), with bevels 36 on the two main squeeze jaws 30 interaction.
  • the bevels 36 taper the width of the squeeze surfaces 32a of the main jaws to the width of the associated extension pieces 33a. They produce the inner edge 19 of the bevels in the finished discharge vessel (FIG. 1).
  • the four crimping jaws 30, 31 do not abut one another in the closed, that is to say crimping state, but rather leave some leeway, so that in the region of the crimping surfaces 32a, 32b the bead 15 of the crimp, which is double-T-shaped in cross section can train.
  • the squeezing surfaces 32a of the main jaws 30 also have the known centering knobs 37 and centering recesses 38 for the power supply lines and for the holding wire 9 arranged in the center.
  • the main crimping jaws 30 have a cutout 39 in the area of the zenith, that is to say at the point where the pump tube 22 'starts.
  • preforming can be dispensed with, for example, if electrode shafts are used which are arranged parallel to the optical axis.
  • the pump tube can be attached by attaching a separate cannula to the tapered tube end, so that there is no need to pull the pump tube out of the end of the tube section.
  • the pipe section 20a in particular can be heated to the pinch temperature before the electrode system 28 is inserted.
  • the cleaning rinsing can also be carried out at any time before the squeezing process.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Vessels And Coating Films For Discharge Lamps (AREA)
  • Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)
  • Discharge Lamp (AREA)
EP93115390A 1992-10-05 1993-09-23 Méthode de fabrication d'une lampe à décharge à haute pression de faible puissance à pincement unique et lampes à décharge à haute pression. Withdrawn EP0591777A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4233469A DE4233469A1 (de) 1992-10-05 1992-10-05 Verfahren zur Herstellung einer einseitig gequetschten Hochdruckentladungslampe kleiner Leistung und Hochdruckentladungslampen
DE4233469 1992-10-05

Publications (2)

Publication Number Publication Date
EP0591777A2 true EP0591777A2 (fr) 1994-04-13
EP0591777A3 EP0591777A3 (fr) 1995-05-24

Family

ID=6469688

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93115390A Withdrawn EP0591777A3 (fr) 1992-10-05 1993-09-23 Méthode de fabrication d'une lampe à décharge à haute pression de faible puissance à pincement unique et lampes à décharge à haute pression.

Country Status (4)

Country Link
US (1) US5528101A (fr)
EP (1) EP0591777A3 (fr)
JP (1) JPH06140001A (fr)
DE (1) DE4233469A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005122206A3 (fr) * 2004-06-09 2008-03-06 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Procede d'usinage d'une lampe et lampe usinee selon un tel procede

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5825129A (en) * 1996-05-31 1998-10-20 U.S. Philips Corporation High pressure discharge lamp having pirch seals
DE19623499A1 (de) * 1996-06-12 1997-12-18 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Verfahren zur Herstellung einer Halogenglühlampe
JP3988177B2 (ja) * 2000-02-02 2007-10-10 ニプロ株式会社 ウェッジベース電球
JP3926211B2 (ja) * 2002-05-29 2007-06-06 日本碍子株式会社 高圧水銀灯および高圧水銀灯用封止材
JP4555591B2 (ja) * 2004-03-31 2010-10-06 株式会社トゥルーウェル 片口放電灯の製造方法
GB2424992B (en) * 2005-04-07 2009-04-01 Gen Electric Lamp capsule pinch seal and method of making such a seal
US8102121B2 (en) * 2007-02-26 2012-01-24 Osram Sylvania Inc. Single-ended ceramic discharge lamp
JP2011181450A (ja) * 2010-03-03 2011-09-15 Panasonic Corp ランプ

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB476833A (en) * 1936-09-25 1937-12-16 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Improvements in or relating to high-pressure metal-vapour electric discharge lamps
DE1238571B (de) * 1964-03-04 1967-04-13 Patra Patent Treuhand Vorrichtung zum Verschliessen eines Lampen-gefaesses und mit der Vorrichtung hergestellte elektrische Lampe
JPS56168318A (en) * 1980-05-29 1981-12-24 Mitsubishi Electric Corp Manufacture of luminous tube for discharge lamp
US4434386A (en) * 1981-12-28 1984-02-28 Gte Products Corporation Process and apparatus for forming lamp capsules
DE3232207A1 (de) * 1982-08-30 1984-03-08 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH, 8000 München Hochdruckentladungslampe kleiner leistung
DE3425894A1 (de) * 1984-07-13 1986-01-23 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH, 8000 München Elektrische lampe
DE3537878A1 (de) * 1985-10-24 1987-04-30 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Verfahren zur herstellung einer einseitig gequetschten metallhalogenidhochdruckentladungslampe und eine nach diesem verfahren hergestellte lampe
US4723092A (en) * 1985-10-24 1988-02-02 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh Method of making a single-ended metal halide high-pressure discharge lamp, and single-ended lamp made according to the method
US4850499A (en) * 1986-12-18 1989-07-25 Gte Products Corporation Method to reduce color temperature variation in metal halide arc tubes
US5051655A (en) * 1987-01-28 1991-09-24 Venture Lighting International, Inc. Electrodes for single ended arc discharge tubes
US4998036A (en) * 1987-12-17 1991-03-05 Kabushiki Kaisha Toshiba Metal vapor discharge lamp containing an arc tube with particular bulb structure
JPH0834094B2 (ja) * 1988-02-26 1996-03-29 東芝ライテック株式会社 メタルハライドランプ
DE3838697A1 (de) * 1988-11-15 1990-05-17 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Verfahren zur herstellung eines lampengefaesses
US5037342A (en) * 1988-11-15 1991-08-06 Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen M.B.H. Method of making an electric lamp, and more particularly a lamp vessel in which electrodes are retained in the lamp by a pinch or press seal
DD278222A1 (de) * 1988-12-16 1990-04-25 Narva Gluehlampen Halogenmetalldampflampe kleiner leistung
DE3842772A1 (de) * 1988-12-19 1990-06-21 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Verfahren zur herstellung einer zweiseitigen hochdruckentladungslampe
EP0451647B1 (fr) * 1990-04-12 1995-07-05 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Lampe à décharge à haute pression et son procédé de fabrication

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005122206A3 (fr) * 2004-06-09 2008-03-06 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Procede d'usinage d'une lampe et lampe usinee selon un tel procede

Also Published As

Publication number Publication date
US5528101A (en) 1996-06-18
JPH06140001A (ja) 1994-05-20
EP0591777A3 (fr) 1995-05-24
DE4233469A1 (de) 1994-04-07

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