EP0456907B1 - High-pressure discharge lamp - Google Patents

High-pressure discharge lamp Download PDF

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Publication number
EP0456907B1
EP0456907B1 EP90124462A EP90124462A EP0456907B1 EP 0456907 B1 EP0456907 B1 EP 0456907B1 EP 90124462 A EP90124462 A EP 90124462A EP 90124462 A EP90124462 A EP 90124462A EP 0456907 B1 EP0456907 B1 EP 0456907B1
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EP
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Prior art keywords
electrode
electrode head
pressure discharge
discharge lamp
head
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EP90124462A
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German (de)
French (fr)
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EP0456907A2 (en
EP0456907A3 (en
Inventor
Dietrich Dr. Fromm
Andreas Dr. Hohlfeld
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Osram GmbH
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Patent Treuhand Gesellschaft fuer Elektrische Gluehlampen mbH
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    • 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

Definitions

  • the invention relates to a high-pressure discharge lamp with a metal halide filling according to the preamble of claim 1.
  • High-pressure discharge lamps with a metal halide filling usually have a pin electrode as the electrode material, which is composed of a core pin and one or more wire coils wound one above the other around the end of the pin. The tip of the pin protrudes beyond the wire helices forming the electrode head in order to serve as a starting point for the discharge arc.
  • a pin electrode as the electrode material, which is composed of a core pin and one or more wire coils wound one above the other around the end of the pin.
  • the tip of the pin protrudes beyond the wire helices forming the electrode head in order to serve as a starting point for the discharge arc.
  • An example of such an electrode construction can be found in US Pat. No. 4,396,857. However, this construction has proven unsuitable for high-pressure discharge lamps with metal halide fillings which contain the metals sodium and tin and are used to produce color temperatures of 2700 to 3400 K .
  • Such fillings cause a rapid erosion of the electrode tips when the lamp is in operation, followed by arc lengthening and an increase in the operating voltage and re-ignition tip.
  • the electrode erosion process thus limits the lifespan because the lamp goes out, when the re-ignition peak exceeds the open circuit voltage.
  • the erosion of the electrode tips can be reduced by a more solid design of the electrode pin in the area of the arc attachment point.
  • the flicker factor increases with these lamps in 50 to 60 Hz operation. This is perceived by the viewer as unpleasant when these lamps are used in the interior, for which they are intended in particular.
  • the invention has for its object to provide a metal halide high-pressure discharge lamp in which the electrode erosion and flicker factor can be kept small and the lamp properties remain unchanged when the lamp is rotated about the arc axis by using a special electrode construction despite the use of sodium and tin as filling substances.
  • the electrodes should have a simple structure, be inexpensive to manufacture and have axial symmetry.
  • the flicker factor can be further improved by an even smaller value for the pin diameter, as it results from the formula listed above, since the heat dissipation responsible for the factor is then further reduced from the electrode head to the pinch.
  • this has no advantages, since the corrosion of the thin electrode pin caused by the filling system mentioned at the transition to the pinch leads to premature failure of the lamp.
  • the value at the root of the above formula may therefore be reduced by a maximum of 0.02.
  • this value may also be increased by a maximum of 0.02, otherwise the flicker factor exceeds the interference threshold of 0.25%.
  • the electrode head must have a substantially cylindrical or frustoconical shape and the tip of the electrode pin must not extend beyond the end of the electrode head facing the discharge arc.
  • the permissible electrode mass is increased by the requirement of a flicker factor limited to ⁇ 0.25%.
  • the lower limit specified in the formula must not be fallen below, because otherwise the burning mechanism described above will lower the average service life below the required 6000 hours.
  • a further improvement in the flicker factor can be achieved if the tip of the electrode pin is set back by one or two pin diameters relative to the end of the electrode head facing the discharge arc, so that there is a small depression in the center at the end face of the head.
  • the manufacture of the electrode is very simple and inexpensive if the electrode head is formed from one or more wire coils that are wound one above the other.
  • BSD wire is advantageously used as the wire, a tungsten wire to which small amounts of potassium have been added in order to make it easier to process.
  • the electrode head can also consist of a tungsten sintered body.
  • the 70 W high-pressure discharge lamp 1 shown in FIG. 1 consists of a discharge vessel 2 made of quartz glass, which is squeezed on both sides and is enclosed by an outer bulb 3.
  • the electrodes 4, 5 - shown schematically - are melted gas-tight into the discharge vessel 2 by means of foils 6, 7 and via current leads 8, 9, sealing foils 10, 11 of the outer bulb 3 and via further short current leads with the electrical connections of the ceramic base (R7s) 12 , 13 connected.
  • a getter material 14 applied to a metal plate is additionally melted potential-free - via a piece of wire.
  • the ends 15, 16 of the discharge vessel 2 are provided with a heat-reflecting coating.
  • the discharge vessel 2 contains metal iodides and bromides of sodium, tin, thallium, indium and lithium as the filling.
  • Lamp 1 - with a power consumption of 70 W - has a luminous efficacy of 70 lm / W at a nominal current (effective value) of 0.9 A.
  • FIG. 2 shows an electrode 4, 5 as it is installed in the high-pressure discharge lamp 1 according to FIG. 1.
  • the electrode 4, 5 consists of an electrode pin 17 with a length of 7.2 mm and a diameter of 0.25 mm, which extends over the sealing foils 6, 7 is sealed gas-tight in the pinch 18.
  • the electrode head 19 is formed from a double-layer coil, the inner coil 20 consisting of six tightly wound turns and the outer coil 21 consisting of four tightly wound turns of a wire with a diameter of 0.2 mm.
  • the electrode head 19 formed from the double-layer coil protrudes 0.5 mm beyond the free end of the electrode pin 17. Both the electrode head and the electrode pin are made of BSD wire.
  • the electrode head contains no emitter material.
  • FIG. 3 shows the structure of a 35 W high-pressure discharge lamp 22 according to the invention with a discharge vessel 23 made of quartz glass that is squeezed on one side, the latter being surrounded by an outer bulb 24 in a gas-tight manner.
  • the electrodes 25, 26 - shown schematically - are melted into the discharge vessel 23 via foils 27, 28 and via current leads 29, 30, sealing foils 31, 32 of the outer bulb 24 and via further short current leads with the electrical connection pins 33, 34 of the ceramic base (G 12) 35 connected.
  • a getter material 37 is also attached to the pinch 36 of the discharge vessel 23 in a potential-free manner via a piece of wire on a metal plate.
  • the filling elements of this lamp 22 correspond to those of the 70 W high-pressure discharge lamp 1 listed above.
  • the 35 W high-pressure discharge lamp 22 has a luminous efficacy of 57 lm / W at a nominal current (effective value) of 0.5 A.
  • FIG. 4 shows an electrode 25 of the high-pressure discharge lamp 22 according to FIG. 3.
  • the electrode 25 consists of an electrode pin 38, one end of which is melted into the pinch 36 in a gas-tight manner via the sealing film 27.
  • the other end of the pin 38 is bent at a right angle to the rest of the pin, so that the electrode head 39 attached to this end points in the direction of the discharge arc.
  • This electrode head 39 also consists of a double-layer coil, the inner coil 40 consisting of six tightly wound turns and the outer coil 41 consisting of four tightly wound turns.
  • the electrode head 39 protrudes slightly beyond the free end of the electrode pin 38.
  • This electrode also consists of BSD wire and contains no emitter material.

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  • Discharge Lamp (AREA)
  • Discharge Lamps And Accessories Thereof (AREA)

Description

Die Erfindung behandelt eine Hochdruckentladungslampe mit einer Metallhalogenidfüllung gemäß dem Oberbegriff des Anspruchs 1.The invention relates to a high-pressure discharge lamp with a metal halide filling according to the preamble of claim 1.

Hochdruckentladungslampen mit Metallhalogenidfüllung besitzen als Elektrodenmaterial meist eine Stiftelektrode, die sich aus einem Kernstift und einer oder mehrerer übereinander um das Ende des Stiftes gewickelter Drahtwendeln zusammensetzt. Die Spitze des Stiftes ragt über die den Elektrodenkopf bildenden Drahtwendeln hinaus, um als Ansatzpunkt für den Entladungsbogen zu dienen. Ein Beispiel für eine solche Elektrodenkonstruktion findet sich in der US-PS 4 396 857. Diese Konstruktion hat sich jedoch bei Hochdruckentladungslampen mit Metallhalogenidfüllungen, die die Metalle Natrium und Zinn enthalten und zur Erzeugung von Farbtemperaturen von 2700 bis 3400 K verwendet werden, als ungeeignet herausgestellt. Solche Füllungen bewirken beim Betrieb der Lampe einen schnellen Abbrand der Elektrodenspitzen, gefolgt von Bogenverlängerung und Anstieg von Brennspannung und Wiederzündspitze. Der Elektrodenabbrandprozeß begrenzt somit die Lebensdauer, da die Lampe verlöscht, wenn die Wiederzündspitze die Leerlaufspannung übertrifft.High-pressure discharge lamps with a metal halide filling usually have a pin electrode as the electrode material, which is composed of a core pin and one or more wire coils wound one above the other around the end of the pin. The tip of the pin protrudes beyond the wire helices forming the electrode head in order to serve as a starting point for the discharge arc. An example of such an electrode construction can be found in US Pat. No. 4,396,857. However, this construction has proven unsuitable for high-pressure discharge lamps with metal halide fillings which contain the metals sodium and tin and are used to produce color temperatures of 2700 to 3400 K . Such fillings cause a rapid erosion of the electrode tips when the lamp is in operation, followed by arc lengthening and an increase in the operating voltage and re-ignition tip. The electrode erosion process thus limits the lifespan because the lamp goes out, when the re-ignition peak exceeds the open circuit voltage.

Der Abbrand der Elektrodenspitzen kann durch eine massivere Ausgestaltung des Elektrodenstiftes im Bereich des Bogenansatzpunktes reduziert werden. Allerdings erhöht sich dadurch bei diesen Lampen beim 50 bis 60 Hz-Betrieb der Flickerfaktor. Dies wird bei Anwendung dieser Lampen im Innenraumbereich, wofür sie insbesondere vorgesehen sind, vom Betrachter als unangenehm empfunden.The erosion of the electrode tips can be reduced by a more solid design of the electrode pin in the area of the arc attachment point. However, the flicker factor increases with these lamps in 50 to 60 Hz operation. This is perceived by the viewer as unpleasant when these lamps are used in the interior, for which they are intended in particular.

Der Erfindung liegt die Aufgabe zugrunde, eine Metallhalogenid-Hochdruckentladungslampe zu schaffen, bei der durch eine spezielle Elektrodenkonstruktion trotz Verwendung von Natrium und Zinn als Füllungssubstanzen der Elektrodenabbrand und der Flickerfaktor klein gehalten werden kann und die Lampeneigenschaften bei Drehung der Lampe um die Bogenachse unverändert bleiben. Die Elektroden sollten einen einfachen Aufbau aufweisen, kostengünstig herzustellen sein und Axialsymmetrie aufweisen.The invention has for its object to provide a metal halide high-pressure discharge lamp in which the electrode erosion and flicker factor can be kept small and the lamp properties remain unchanged when the lamp is rotated about the arc axis by using a special electrode construction despite the use of sodium and tin as filling substances. The electrodes should have a simple structure, be inexpensive to manufacture and have axial symmetry.

Die Aufgabe wird bei der erfindungsgemäßen Hochdruckentladungslampe durch die kennzeichnenden Merkmale des Anspruchs 1 gelöst. Weitere vorteilhafte Ausgestaltungen sind den Unteransprüchen zu entnehmen.The object is achieved in the high-pressure discharge lamp according to the invention by the characterizing features of claim 1. Further advantageous refinements can be found in the subclaims.

Messungen an solchen Elektroden haben gezeigt, daß diese sowohl bezüglich des Elektrodenabbrands als auch des Flickerfaktors optimale Eigenschaften besitzen, wenn der Durchmesser d in mm des Elektrodenstifts der Formel d = 0,083 x i L

Figure imgb0001
genügt, wobei iL der Effektivwert des Lampenstroms in A ist.Measurements on such electrodes have shown that they have optimal properties with regard to both electrode erosion and flicker factor if the diameter d in mm of the electrode pin of the formula d = 0.083 xi L
Figure imgb0001
 is sufficient, where i L is the effective value of the lamp current in A.

Prinzipiell läßt sich durch einen noch kleineren Wert für den Stiftdurchmesser, wie er sich aus der oben aufgeführten Formel ergibt, der Flickerfaktor weiter verbessern, da dann die für den Faktor verantwortliche Wärmeableitung vom Elektrodenkopf in die Quetschung weiter reduziert wird. Praktisch bringt dies jedoch keine Vorteile, da dann die durch das genannte Füllungssystem verursachte Korrosion des dünnen Elektrodenstiftes am Übergang zur Quetschung zu einem vorzeitigen Ausfall der Lampe führt. Um die für diesen Lampentyp geforderte mittlere Lebensdauer von 6000 Std. zu erreichen, darf daher der in der obigen Formel unter der Wurzel stehende Wert um höchstens 0,02 verkleinert werden. Andererseits darf dieser Wert auch um höchstens 0,02 vergrößert werden, da sonst der Flickerfaktor die Störschwelle von 0,25 % übersteigt. Der zulässige Bereich für den Durchmesser des Elektrodenstiftes kann daher durch die Formel d = 0,083 x i L ± 0,02

Figure imgb0002
eingegrenzt werden.In principle, the flicker factor can be further improved by an even smaller value for the pin diameter, as it results from the formula listed above, since the heat dissipation responsible for the factor is then further reduced from the electrode head to the pinch. In practice, however, this has no advantages, since the corrosion of the thin electrode pin caused by the filling system mentioned at the transition to the pinch leads to premature failure of the lamp. In order to achieve the average lifespan of 6000 hours required for this type of lamp, the value at the root of the above formula may therefore be reduced by a maximum of 0.02. On the other hand, this value may also be increased by a maximum of 0.02, otherwise the flicker factor exceeds the interference threshold of 0.25%. The permissible range for the diameter of the electrode pin can therefore be determined by the formula d = 0.083 xi L ± 0.02
Figure imgb0002
 be narrowed down.

Der Elektrodenkopf muß eine im wesentlichen zylindrische oder kegelstumpfförmige Gestalt aufweisen und die Spitze des Elektrodenstiftes darf nicht über das dem Entladungsbogen zugewandte Ende des Elektrodenkopfes hinausgehen. Die Masse M des Elektrodenkopfes in mg, einschließlich des darin befindlichen Teils des Elektrodenstiftes, wird nach oben und unten durch die Formel M = i L x (23 ± 8)

Figure imgb0003
eingegrenzt, wobei iL der Effektivwert des Lampenstroms in A ist. Die zulässige Elektrodenmasse wird dabei nach oben durch die Forderung eines Flickerfaktors von ≦ 0,25 % beschränkt. Andererseits darf auch die in der Formel angegebene Untergrenze nicht unterschritten werden, weil sonst der oben beschriebene Abbrandmechanismus die mittlere Lebensdauer unter die geforderten 6000 Std. absenkt.The electrode head must have a substantially cylindrical or frustoconical shape and the tip of the electrode pin must not extend beyond the end of the electrode head facing the discharge arc. The mass M of the electrode head in mg, including the part of the electrode pin located therein, is increased and decreased by the formula M = i L x (23 ± 8)
Figure imgb0003
 limited, where i L is the effective value of the lamp current in A. The permissible electrode mass is increased by the requirement of a flicker factor limited to ≦ 0.25%. On the other hand, the lower limit specified in the formula must not be fallen below, because otherwise the burning mechanism described above will lower the average service life below the required 6000 hours.

Eine weitere Verbesserung des Flickerfaktors läßt sich erzielen, wenn die Spitze des Elektrodenstiftes gegenüber dem dem Entladungsbogen zugewandten Ende des Elektrodenkopfes um ein bis zwei Stiftdurchmesser zurückgesetzt ist, so daß sich an der Stirnseite des Kopfes im Zentrum eine kleine Mulde ergibt.A further improvement in the flicker factor can be achieved if the tip of the electrode pin is set back by one or two pin diameters relative to the end of the electrode head facing the discharge arc, so that there is a small depression in the center at the end face of the head.

Die Herstellung der Elektrode gestaltet sich sehr einfach und kostengünstig, wenn der Elektrodenkopf aus einer oder mehrerer übereinandergewickelter Drahtwendeln gebildet wird. Als Draht wird vorteilhaft BSD-Draht verwendet, ein Wolframdraht, dem zwecks einer günstigeren Verarbeitbarkeit geringe Mengen an Kalium beigegeben sind. Der Elektrodenkopf kann aber auch aus einem Wolfram-Sinterkörper bestehen.The manufacture of the electrode is very simple and inexpensive if the electrode head is formed from one or more wire coils that are wound one above the other. BSD wire is advantageously used as the wire, a tungsten wire to which small amounts of potassium have been added in order to make it easier to process. However, the electrode head can also consist of a tungsten sintered body.

Die Erfindung ist an Hand der folgenden Ausführungsbeispiele veranschaulicht.

Figur 1
zeigt den Aufbau einer erfindungsgemäßen Hochdruckentladungslampe mit zweiseitig gequetschtem Entladungsgefäß
Figur 2
zeigt eine Elektrode für eine Hochdruckentladungslampe gemäß Figur 1
Figur 3
zeigt den Aufbau einer erfindungsgemäßen Hochdruckentladungslampe mit einseitig gequetschtem Entladungsgefäß
Figur 4
zeigt eine Elektrode für eine Hochdruckentladungslampe gemäß Figur 3
The invention is illustrated by the following exemplary embodiments.
Figure 1
shows the structure of a high-pressure discharge lamp according to the invention with a discharge vessel squeezed on both sides
Figure 2
shows an electrode for a high-pressure discharge lamp according to FIG. 1
Figure 3
shows the structure of a high-pressure discharge lamp according to the invention with a discharge vessel squeezed on one side
Figure 4
shows an electrode for a high-pressure discharge lamp according to FIG. 3

Die in Figur 1 dargestellte 70 W-Hochdruckentladungslampe 1 besteht aus einem zweiseitig gequetschten Entladungsgefäß 2 aus Quarzglas, das von einem Außenkolben 3 umschlossen ist. Die Elektroden 4, 5 - schematisch dargestellt - sind mittels Folien 6, 7 gasdicht in das Entladungsgefäß 2 eingeschmolzen und über Stromzuführungen 8, 9, Dichtungsfolien 10, 11 des Außenkolbens 3 und über weitere kurze Stromzuführungen mit den elektrischen Anschlüssen der Keramiksockel (R7s) 12, 13 verbunden. In eine Quetschung des Entladungsgefäßes 2 ist zusätzlich - über ein Drahtstück - ein auf einem Metallplättchen aufgebrachtes Gettermaterial 14 potentialfrei eingeschmolzen. Die Enden 15, 16 des Entladungsgefäßes 2 sind mit einem wärmereflektierenden Belag versehen. Als Füllung enthält das Entladungsgefäß 2 neben Quecksilber und einem Edelgas Metalljodide und -bromide von Natrium, Zinn, Thallium, Indium und Lithium. Die Lampe 1 - mit einer Leistungsaufnahme von 70 W - weist bei einem Nennstrom (Effektivwert) von 0,9 A eine Lichtausbeute von 70 lm/W auf.The 70 W high-pressure discharge lamp 1 shown in FIG. 1 consists of a discharge vessel 2 made of quartz glass, which is squeezed on both sides and is enclosed by an outer bulb 3. The electrodes 4, 5 - shown schematically - are melted gas-tight into the discharge vessel 2 by means of foils 6, 7 and via current leads 8, 9, sealing foils 10, 11 of the outer bulb 3 and via further short current leads with the electrical connections of the ceramic base (R7s) 12 , 13 connected. In a pinch of the discharge vessel 2, a getter material 14 applied to a metal plate is additionally melted potential-free - via a piece of wire. The ends 15, 16 of the discharge vessel 2 are provided with a heat-reflecting coating. In addition to mercury and a noble gas, the discharge vessel 2 contains metal iodides and bromides of sodium, tin, thallium, indium and lithium as the filling. Lamp 1 - with a power consumption of 70 W - has a luminous efficacy of 70 lm / W at a nominal current (effective value) of 0.9 A.

Figur 2 zeigt eine Elektrode 4, 5, wie sie in der Hochdruckentladungslampe 1 gemäß Figur 1 eingebaut ist. Die Elektrode 4, 5 besteht aus einem Elektrodenstift 17 mit 7,2 mm Länge und einem Durchmesser von 0,25 mm, der über die Dichtungsfolien 6, 7 gasdicht in die Quetschung 18 eingeschmolzen ist. Der Elektrodenkopf 19 wird aus einer Doppellagenwendel gebildet, wobei die innere Wendel 20 aus sechs dicht gewickelten Windungen und die äußere Wendel 21 aus vier dicht gewickelten Windungen eines Drahtes mit einem Durchmesser von 0,2 mm besteht. Der aus der Doppellagenwendel gebildete Elektrodenkopf 19 steht 0,5 mm über das freie Ende des Elektrodenstiftes 17 hinaus. Sowohl der Elektrodenkopf als auch der Elektrodenstift bestehen aus BSD-Draht. Der Elektrodenkopf enthält kein Emittermaterial.FIG. 2 shows an electrode 4, 5 as it is installed in the high-pressure discharge lamp 1 according to FIG. 1. The electrode 4, 5 consists of an electrode pin 17 with a length of 7.2 mm and a diameter of 0.25 mm, which extends over the sealing foils 6, 7 is sealed gas-tight in the pinch 18. The electrode head 19 is formed from a double-layer coil, the inner coil 20 consisting of six tightly wound turns and the outer coil 21 consisting of four tightly wound turns of a wire with a diameter of 0.2 mm. The electrode head 19 formed from the double-layer coil protrudes 0.5 mm beyond the free end of the electrode pin 17. Both the electrode head and the electrode pin are made of BSD wire. The electrode head contains no emitter material.

In Figur 3 ist der Aufbau einer erfindungsgemäßen 35 W-Hochdruckentladungslampe 22 mit einseitig gequetschtem Entladungsgefäß 23 aus Quarzglas dargestellt, wobei letzteres von einem Außenkolben 24 gasdicht umgeben ist. Die Elektroden 25, 26 - schematisch dargestellt - sind über Folien 27, 28 in das Entladungsgefäß 23 eingeschmolzen und über Stromzuführungen 29, 30, Dichtungsfolien 31, 32 des Außenkolbens 24 und über weitere kurze Stromzuführungen mit den elektrischen Anschlußstiften 33, 34 des Keramiksockels (G 12) 35 verbunden. An der Quetschung 36 des Entladungsgefäßes 23 ist außerdem ein Gettermaterial 37 auf einem Metallplättchen - über ein Drahtstück - potentialfrei befestigt. Die Füllungselemente dieser Lampe 22 entsprechen denen der oben aufgeführten 70 W-Hochdruckentladungslampe 1. Die 35 W-Hochdruckentladungslampe 22 besitzt bei einem Nennstrom (Effektivwert) von 0,5 A eine Lichtausbeute von 57 lm/W.FIG. 3 shows the structure of a 35 W high-pressure discharge lamp 22 according to the invention with a discharge vessel 23 made of quartz glass that is squeezed on one side, the latter being surrounded by an outer bulb 24 in a gas-tight manner. The electrodes 25, 26 - shown schematically - are melted into the discharge vessel 23 via foils 27, 28 and via current leads 29, 30, sealing foils 31, 32 of the outer bulb 24 and via further short current leads with the electrical connection pins 33, 34 of the ceramic base (G 12) 35 connected. A getter material 37 is also attached to the pinch 36 of the discharge vessel 23 in a potential-free manner via a piece of wire on a metal plate. The filling elements of this lamp 22 correspond to those of the 70 W high-pressure discharge lamp 1 listed above. The 35 W high-pressure discharge lamp 22 has a luminous efficacy of 57 lm / W at a nominal current (effective value) of 0.5 A.

Figur 4 zeigt eine Elektrode 25 der Hochdruckentladungslampe 22 gemäß Figur 3. Die Elektrode 25 besteht aus einem Elektrodenstift 38, dessen eines Ende über die Dichtungsfolie 27 gasdicht in die Quetschung 36 eingeschmolzen ist. Das andere Ende des Stiftes 38 ist im rechten Winkel zum übrigen Stift umgebogen, damit der an diesem Ende befestigte Elektrodenkopf 39 in Richtung des Entladungsbogens weist. Auch dieser Elektrodenkopf 39 besteht aus einer Doppellagenwendel, wobei die innere Wendel 40 aus sechs dicht gewickelten Windungen und die äußere Wendel 41 aus vier dicht gewickelten Windungen besteht. Der Elektrodenkopf 39 steht etwas über das freie Ende des Elektrodenstiftes 38 hinaus. Auch diese Elektrode besteht aus BSD-Draht und enthält kein Emittermaterial.FIG. 4 shows an electrode 25 of the high-pressure discharge lamp 22 according to FIG. 3. The electrode 25 consists of an electrode pin 38, one end of which is melted into the pinch 36 in a gas-tight manner via the sealing film 27. The other end of the pin 38 is bent at a right angle to the rest of the pin, so that the electrode head 39 attached to this end points in the direction of the discharge arc. This electrode head 39 also consists of a double-layer coil, the inner coil 40 consisting of six tightly wound turns and the outer coil 41 consisting of four tightly wound turns. The electrode head 39 protrudes slightly beyond the free end of the electrode pin 38. This electrode also consists of BSD wire and contains no emitter material.

Claims (5)

  1. High-pressure discharge lamp (1, 22) with a power of less than or equal to 400 W, whose discharge vessel (2, 23) contains a filling of mercury, metal halides, especially of sodium and tin, as well as at least one inert gas, and into which two electrodes (4, 5; 25, 26) are sealed in a gas-tight fashion via sealing foils (6, 7; 27, 28), each electrode (4, 5; 25, 26) comprising an electrode shaft (17; 38) and an electrode head (19, 39) mounted thereon, characterized in that each electrode (4, 5; 25, 26) has the following features:
    - the electrode head (19, 39) has an outer contour which is essentially cylindrical or frusto-conical,
    - the tip of the electrode shaft (17, 38) carrying the electrode head (19, 39) reaches at most up to the end of the electrode head (19, 39) facing the discharge arc,
    - the electrode shaft (17, 38) has a diameter d in mm whose maximum and minimum permissible values are determined in accordance with the formula d = 0.083 × i L ± 0.02 ,
    Figure imgb0007
     iL being the r.m.s. value of the lamp current in A, and
    - the electrode head (19, 39), including the part of the electrode shaft (17, 38) located therein, has a mass M in mg whose maximum and minimum permissible values are determined by the formula M = iL × (23 ± 8), iL being the r.m.s. value of the lamp current in A.
  2. High-pressure discharge lamp according to Claim 1, characterized in that the tip of the electrode shaft (17, 38) carrying the electrode head (19, 39) is somewhat recessed with respect to the end of the electrode head (19, 39) facing the discharge arc.
  3. High-pressure discharge lamp according to Claim 1, characterized in that the electrode head (19, 39) comprises one or more layers of wire filaments wound one above another.
  4. High-pressure discharge lamp according to Claims 1 and 3, characterized in that the electrode shaft (17, 38) and the wire filaments of the electrode head (19, 39) are composed of tungsten which contains small admixtures of potassium (BSD wire).
  5. High-pressure discharge lamp according to Claim 1, characterized in that the electrode head comprises a sintered body of pure tungsten.
EP90124462A 1990-03-15 1990-12-17 High-pressure discharge lamp Expired - Lifetime EP0456907B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4008375 1990-03-15
DE4008375A DE4008375A1 (en) 1990-03-15 1990-03-15 HIGH PRESSURE DISCHARGE LAMP

Publications (3)

Publication Number Publication Date
EP0456907A2 EP0456907A2 (en) 1991-11-21
EP0456907A3 EP0456907A3 (en) 1992-03-18
EP0456907B1 true EP0456907B1 (en) 1995-03-22

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ID=6402322

Family Applications (1)

Application Number Title Priority Date Filing Date
EP90124462A Expired - Lifetime EP0456907B1 (en) 1990-03-15 1990-12-17 High-pressure discharge lamp

Country Status (4)

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US (1) US5210463A (en)
EP (1) EP0456907B1 (en)
JP (1) JP2947958B2 (en)
DE (2) DE4008375A1 (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1176017A (en) * 1995-11-02 1998-03-11 菲利浦电子有限公司 High-pressure discharge lamp
US6084351A (en) * 1996-09-06 2000-07-04 Matsushita Electric Industrial Co., Ltd. Metal halide lamp and temperature control system therefor
DE19749908A1 (en) * 1997-11-11 1999-05-12 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Electrode component for discharge lamps
JP2004521474A (en) * 2001-06-25 2004-07-15 コーニンクレッカ　フィリップス　エレクトロニクス　エヌ　ヴィ High pressure gas discharge lamp and method of manufacturing high pressure gas discharge lamp
GB2444977A (en) * 2006-12-21 2008-06-25 Gen Electric An ultra high pressure mercury arc lamp
US8460045B2 (en) * 2007-06-25 2013-06-11 General Electric Company High intensity discharge lamp with enhanced dimming characteristcs
DE102007050633A1 (en) 2007-10-23 2009-04-30 Osram Gesellschaft mit beschränkter Haftung Method and device for operating a gas discharge lamp
DE102008016888A1 (en) 2008-04-02 2009-10-08 Osram Gesellschaft mit beschränkter Haftung Switching arrangement for stabilized operation of high pressure discharge lamp in headlight for motor vehicle, has capacitor connected with inverter, such that commutation voltage increases lamp voltage during commutation phase of lamp
JP2011181450A (en) * 2010-03-03 2011-09-15 Panasonic Corp Lamp
CN103286649A (en) * 2012-02-29 2013-09-11 上海亚尔光源有限公司 Method for manufacturing electrode for ultraviolet lamp

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB486138A (en) * 1937-01-19 1938-05-31 Gen Electric Co Ltd Improvements in electrodes for high-pressure metal vapour electric discharge devices
GB491176A (en) * 1937-05-20 1938-08-29 Gen Electric Co Ltd Improvements in high-pressure metal-vapour electric discharge devices
US3670195A (en) * 1970-03-20 1972-06-13 Japan Broadcasting Corp Metal vapour discharge lamp
JPS592145B2 (en) * 1979-10-01 1984-01-17 株式会社東芝 short arc light discharge lamp
US4396857A (en) * 1980-07-01 1983-08-02 General Electric Company Arc tube construction
US4633136A (en) * 1982-04-20 1986-12-30 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh High-pressure discharge lamp with low power input
DE3232207A1 (en) * 1982-08-30 1984-03-08 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH, 8000 München HIGH PRESSURE DISCHARGE LAMP WITH LOW POWER
US5001397A (en) * 1985-07-17 1991-03-19 U.S. Philips Corporation High-pressure gas discharge lamp having electrodes with coil layers having interlocking turns
JPS6247941A (en) * 1985-08-28 1987-03-02 Toshiba Corp Small-sized high pressure metal vapor discharge lamp
DE3641045A1 (en) * 1986-12-01 1988-06-09 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh HIGH PRESSURE DISCHARGE LAMP, SEMI-SIDED
DE69011145T2 (en) * 1989-01-31 1995-01-19 Toshiba Lighting & Technology Metal vapor discharge lamp pinched on one side.
US4968916A (en) * 1989-09-08 1990-11-06 General Electric Company Xenon-metal halide lamp particularly suited for automotive applications having an improved electrode structure

Also Published As

Publication number Publication date
DE4008375A1 (en) 1991-09-19
US5210463A (en) 1993-05-11
DE59008768D1 (en) 1995-04-27
EP0456907A2 (en) 1991-11-21
JP2947958B2 (en) 1999-09-13
JPH04220939A (en) 1992-08-11
EP0456907A3 (en) 1992-03-18

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