WO2008052893A1 - Circuit arrangement for low-pressure discharge lamps - Google Patents

Circuit arrangement for low-pressure discharge lamps Download PDF

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Publication number
WO2008052893A1
WO2008052893A1 PCT/EP2007/061228 EP2007061228W WO2008052893A1 WO 2008052893 A1 WO2008052893 A1 WO 2008052893A1 EP 2007061228 W EP2007061228 W EP 2007061228W WO 2008052893 A1 WO2008052893 A1 WO 2008052893A1
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WO
WIPO (PCT)
Prior art keywords
circuit arrangement
electrode
arrangement according
power supply
supply lines
Prior art date
Application number
PCT/EP2007/061228
Other languages
German (de)
French (fr)
Inventor
Rüdiger Klam
Paul Lange
Thomas Noll
Ludwig Reiser
Original Assignee
Osram Gesellschaft mit beschränkter Haftung
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.)
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Publication of WO2008052893A1 publication Critical patent/WO2008052893A1/en

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
    • H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
    • H05B41/295—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices and specially adapted for lamps with preheating electrodes, e.g. for fluorescent lamps
    • H05B41/298—Arrangements for protecting lamps or circuits against abnormal operating conditions
    • H05B41/2981—Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the circuit against abnormal operating conditions
    • H05B41/2985—Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the circuit against abnormal operating conditions against abnormal lamp operating conditions
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
    • H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
    • H05B41/295—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices and specially adapted for lamps with preheating electrodes, e.g. for fluorescent lamps
    • H05B41/298—Arrangements for protecting lamps or circuits against abnormal operating conditions
    • H05B41/2988—Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the lamp against abnormal operating conditions
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Definitions

  • the invention relates to a circuit arrangement for operating at least one low-pressure discharge lamp, in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode filaments, which are each connected to power supply lines and form part of a resonant circuit.
  • Such a circuit arrangement for operating a discharge lamp is known, for example, from WO 00/11916 A1 of the Applicant.
  • a low-pressure discharge lamp formed, for example, as a rod-shaped T5 fluorescent lamp is arranged in a resonant circuit such that the two electrode filaments coated with emitter material form part of the resonant circuit.
  • a disadvantage of such a circuit arrangement is that the lamp can no longer be operated if at least one of the electrode filaments is broken, since these are a component of the resonant circuit, which is necessary for generating the ignition voltage and therefore must be intact. That is, after a helical break, the lamp can not be ignited because the resonant circuit is interrupted, so that on the destroyed electrode coils existing residual emitter material is not used up and as a result, the service life potential of the lamp is not fully utilized.
  • the invention has for its object to provide a circuit arrangement, in which over conventional solutions, a lifetime extension of at least one low-pressure discharge lamp with minimal device complexity is possible.
  • a circuit arrangement for operating at least one low-pressure discharge lamp in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode filaments, which are each connected to power supply lines and form part of a resonant circuit, wherein the power supply lines of at least one of the electrode filaments electrically conductively connected or connectable are.
  • the power supply lines of at least one of the electrode coils are electrically or indirectly connected or connectable (coil short circuit or bypass), so that the required for generating the ignition voltage of the lamp resonant circuit over the prior art after one or more Wendelbrüchen is not interrupted , As a result, the lamp can continue to be operated even after a spiral break, so that the emitter material of the electrode coils is essentially completely used up and an extension of the service life of the discharge lamp is made possible by the burning time of the residual emitter amount.
  • the power supply of the electrode coils are permanently connected to cold start lamps. In the case of warm start lamps, the power supply leads are connected after preheating the electrode filaments or through components connected in parallel to the filaments.
  • the power supply lines of the electrode turn are connected in cold start lamps by means of a common connecting line.
  • the power supply lines of the electrode filaments are connected to each other by means of a capacitance (capacitor) and / or an inductance.
  • the inductance preferably forms part of a transformer for preheating the electrode filaments.
  • one of the electrode filaments is designed as a spiral with a longer service life. As a result, a common area of two failure distributions is prevented, so that a greater reliability of the lamp is achieved.
  • the power supply lines of at least one of the electrode coils are preferably embedded in a glass bead, which is provided at least in sections with a coating which has at least one metal hydride, preferably titanium hydride.
  • a coating which has at least one metal hydride, preferably titanium hydride.
  • At least one thermal fuse is arranged in the resonant circuit, which interrupts the resonant circuit and thus further ignition attempts when the low-pressure discharge lamp is not ignited. If the low-pressure discharge lamp does not ignite due to a fault, for example because it no longer has a usable emitter and has been made incapable of firing by the hydrogen of the titanium hydride and the ballast has attempted to ignite unsuccessfully over a defined period of time, the temperature in the region of the thermal fuse increases thermally destroyed at a certain temperature.
  • the thermal fuse is dimensioned such that the critical temperature increase is not achieved during normal operation of the lamp, for example when burning in the downlight.
  • Such a thermal fuse may be formed, for example, as a fuse resistor. Especially with high-resistance electrode filaments, the efficiency of the lamp can be improved by this cost-effective cut-off technique.
  • the thermal fuse is arranged in an embodiment of the invention in series with a resonant capacitor in the resonant circuit.
  • the electrode filaments each have at least two filament legs provided with an emitter material, which are connected by means of At least one electrically insulated coil holder are fixed in position such that the coil legs at an angle of less than 180 ° to each other and thereby have a larger coil length and thus a larger emitter quantity. That is, the electrode filaments can accommodate more Emittermenge with the same winding geometry. As the life scales with the increase in the emitter weight, a substantial improvement in the life of the low-pressure discharge lamp can be achieved. Furthermore, damage to the emitter-free coil ends is reduced by sputtering during a cold start, since the damage is distributed over several coil ends. Due to the further helix limb held over the helix holder, the lamp can continue to operate even when a helix limb is completely destroyed.
  • Figure 1 shows a schematic circuit arrangement according to a first embodiment of the invention
  • Figure 2 is a schematic circuit arrangement according to a second embodiment of the invention.
  • FIG. 1 shows a schematic circuit arrangement 1 for operating at least one low-pressure discharge lamp designed as a fluorescent lamp 2.
  • This one has about rod or tubular discharge vessel 4 made of glass, which is provided on the inside with a phosphor layer, not shown.
  • the discharge vessel 4 has a discharge chamber 6 sealed on both sides, in which two electrode filaments 8, 10 protrude, which are each connected to power supply lines 12, 14 for electrical contacting and form part of a resonance circuit 16. Between the electrode coils 8, 10, a gas discharge is formed in the discharge vessel 4 during lamp operation.
  • the two power supply lines 12, 14 of the electrode coils 8, 10 are each electrically conductively connected to each other, so that the time required to generate the ignition voltage of the fluorescent lamp 2 resonant circuit 16 is not interrupted even after a schematically indicated fraction of the electrode coils 8, 10. As a result, the fluorescent lamp 2 can continue to be operated after a spiral break, so that the emitter material of the electrode coils 8, 10 is essentially completely used up and a service life extension of the lamp 2 by the burning time of the residual emitter quantity is made possible.
  • the power supply lines 12, 14 of the electrode coils 8, 10 are each connected via a connecting line 18, 20, at which the ignition voltage U B is present.
  • the power supply lines 12, 14 of the electrode coils 8, 10 are connected to each other by means of a capacitor, a coil or a series circuit of capacitor and coil.
  • a coil forms part of a transformer for preheating the electrode coils.
  • the power supply lines 12, 14 of the electrode coils 8, 10 are embedded within the discharge vessel 4 in a glass bead, not shown, which is provided with a coating of titanium hydride and a rheological additive. At the end of the life of the fluorescent lamp 2, after the coils 8, 10 are broken and the emitter material is completely used up, the latter changes into a cold cathode mode, which results in an increase in the cathode drop voltage and thus in a strong heating of the electrode system.
  • a thermal fuse 22 is arranged in series with a resonance capacitor 24 in the resonance circuit 16. If the fluorescent lamp 2 does not ignite because it no longer has a usable emitter and has been rendered incapable of burning by the hydrogen of the titanium hydride, the temperature in the region of the thermal fuse 22 increases after a defined number of futile ignition attempts, whereby it is thermally destroyed at a certain temperature.
  • the thermal fuse 22 is dimensioned such that the critical temperature increase is not achieved during normal operation of the lamp 2, for example, when burning in the downlight.
  • Such a thermal fuse 22 may be formed, for example, as a fuse resistor.
  • the efficiency of the lamp 2 can be improved by this cost-effective cut-off technique.
  • the electrode coils 8, 10 each have two provided with an emitter material filament legs, which are fixed in position in the discharge vessel 4 by means of an electrically insulated coil holder such that the filament legs at an angle of about 80 ° to each other and thereby a greater coil length and thus have a larger amount of emitters. As the service life scales with the increase in the emitter weight, a further improvement in the life of the fluorescent lamp 2 can be achieved.
  • Figure 2 shows a circuit arrangement according to the invention 1 according to a further embodiment, which differs from the above-described embodiment essentially in that the left in Figure 2 electrode coil 8 is formed as a helix with longer life and reliability, the power supply lines 12, 14 is not electrically connected to each other. Due to the coil 8 with a longer service life, a common area of two failure distributions of the coils 8, 10 is prevented, so that greater reliability is achieved.
  • the power supply lines 12, 14 of the right-hand electrode coil 10 are connected to one another in an electrically conductive manner via the connecting line 20, so that the resonant circuit 16 required for generating the ignition voltage of the fluorescent lamp 2 is not interrupted even after a schematically indicated rupture of the electrode coil 10.
  • the fluorescent lamp 2 can continue to be operated after a helical break of the helix 10, so that the emitter material of the electrode helices 8, 10 is essentially completely used up and a service life extension of the lamp 2 is achieved.
  • the coupling of the ignition voltage U B takes place at this output Guidance example preferably on the opposite side of the resonant circuit 16 of the circuit arrangement. 1
  • the circuit arrangement 1 according to the invention is not limited to the described resonant circuit 16, but the contacting of the electrode filaments 8, 10 with the ignition voltage U B and their coupling can be carried out in different manner known from the prior art.
  • the power supply lines 12, 14 of at least one of the electrode coils 8, 10 are connected or connectable to one another directly or indirectly in an electrically conductive manner.

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  • Circuit Arrangements For Discharge Lamps (AREA)
  • Discharge Lamps And Accessories Thereof (AREA)
  • Discharge Lamp (AREA)

Abstract

The invention discloses a circuit arrangement for operating at least one low-pressure discharge lamp, in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode filaments, which are each connected to power supply lines and form part of a resonant circuit. According to the invention, the power supply lines of at least one of the electrode filaments are or can be connected electrically conductively indirectly or directly to one another.

Description

Beschreibung description
Schaltungsanordnung für NiederdruckentladungslampenCircuit arrangement for low-pressure discharge lamps
Technisches GebietTechnical area
Die Erfindung betrifft eine Schaltungsanordnung zum Betrieb zumindest einer Niederdruckentladungslampe, ins- besondere einer Leuchtstofflampe oder Kompaktleuchtstofflampe, mit zumindest zwei Elektrodenwendeln, die jeweils mit Stromzuführungen verbunden sind und einen Teil eines Resonanzkreises ausbilden.The invention relates to a circuit arrangement for operating at least one low-pressure discharge lamp, in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode filaments, which are each connected to power supply lines and form part of a resonant circuit.
Stand der TechnikState of the art
Eine derartige Schaltungsanordnung zum Betrieb einer Entladungslampe ist beispielsweise aus der WO 00/11916 Al der Anmelderin bekannt. Bei dieser herkömmlichen Schaltungsanordnung ist eine beispielsweise als stabförmige T5-Leuchtstofflampe ausgebildete Niederdruckentladungslampe in einem Resonanzkreis derart angeordnet, dass die beiden mit Emittermaterial beschichteten Elektrodenwendeln einen Teil des Resonanzkreises ausbilden. Nachteilig bei einer derartigen Schaltungsanordnung ist, dass die Lampe nicht mehr betrieben werden kann, wenn zumindest eine der Elektrodenwendeln gebrochen ist, da diese ein Bestandteil des Resonanzkreises sind, der zur Erzeugung der Zündspannung notwendig ist und daher intakt sein muss. Das heißt, nach einem Wendelbruch kann die Lampe nicht mehr gezündet werden, da der Resonanzkreis unterbrochen ist, so dass auf den zerstörten Elektrodenwendeln vorhandenes Restemittermaterial nicht aufgebraucht und dadurch das Lebensdauerpotenzial der Lampe nicht voll ausgenutzt wird.Such a circuit arrangement for operating a discharge lamp is known, for example, from WO 00/11916 A1 of the Applicant. In this conventional circuit arrangement, a low-pressure discharge lamp formed, for example, as a rod-shaped T5 fluorescent lamp is arranged in a resonant circuit such that the two electrode filaments coated with emitter material form part of the resonant circuit. A disadvantage of such a circuit arrangement is that the lamp can no longer be operated if at least one of the electrode filaments is broken, since these are a component of the resonant circuit, which is necessary for generating the ignition voltage and therefore must be intact. That is, after a helical break, the lamp can not be ignited because the resonant circuit is interrupted, so that on the destroyed electrode coils existing residual emitter material is not used up and as a result, the service life potential of the lamp is not fully utilized.
Darstellung der ErfindungPresentation of the invention
Der Erfindung liegt die Aufgabe zugrunde, eine Schal- tungsanordnung zu schaffen, bei der gegenüber herkömmlichen Lösungen eine Lebensdauerverlängerung zumindest einer Niederdruckentladungslampe mit minimalem vorrichtungstechnischen Aufwand ermöglicht ist.The invention has for its object to provide a circuit arrangement, in which over conventional solutions, a lifetime extension of at least one low-pressure discharge lamp with minimal device complexity is possible.
Diese Aufgabe wird gelöst durch eine Schaltungsanordnung zum Betrieb zumindest einer Niederdruckentladungslampe, insbesondere einer Leuchtstofflampe oder Kompaktleuchtstofflampe, mit zumindest zwei Elektrodenwendeln, die jeweils mit Stromzuführungen verbunden sind und einen Teil eines Resonanzkreises ausbilden, wobei die Stromzuführungen zumindest einer der Elektrodenwendeln elektrisch leitend miteinander verbunden oder verbindbar sind. Besonders vorteilhafte Ausführungen der Erfindung sind in den abhängigen Ansprüchen beschrieben.This object is achieved by a circuit arrangement for operating at least one low-pressure discharge lamp, in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode filaments, which are each connected to power supply lines and form part of a resonant circuit, wherein the power supply lines of at least one of the electrode filaments electrically conductively connected or connectable are. Particularly advantageous embodiments of the invention are described in the dependent claims.
Bei der erfindungsgemäßen Lösung sind die Stromzuführungen zumindest einer der Elektrodenwendeln elektrisch leitend mittelbar oder unmittelbar miteinander verbunden oder verbindbar (Wendelkurzschluss oder Bypass) , so dass der zum Erzeugen der Zündspannung der Lampe erforderliche Resonanzkreis gegenüber dem Stand der Technik nach einem oder mehreren Wendelbrüchen nicht unterbrochen wird. Dadurch kann die Lampe auch nach einem Wendelbruch weiter betrieben werden, so dass das Emittermaterial der Elekt- rodenwendeln im Wesentlichen vollständig aufgebraucht wird und eine Lebensdauerverlängerung der Entladungslampe um die Brenndauer der Restemittermenge ermöglicht ist. Die Stromzuführungen der Elektrodenwendeln sind bei Kaltstartlampen dauerhaft verbunden. Bei Warmstartlampen erfolgt die Verbindung der Stromzuführungen nach dem Vor- heizen der Elektrodenwendeln oder durch zu den Wendeln parallel geschaltete Bauteile.In the solution according to the invention, the power supply lines of at least one of the electrode coils are electrically or indirectly connected or connectable (coil short circuit or bypass), so that the required for generating the ignition voltage of the lamp resonant circuit over the prior art after one or more Wendelbrüchen is not interrupted , As a result, the lamp can continue to be operated even after a spiral break, so that the emitter material of the electrode coils is essentially completely used up and an extension of the service life of the discharge lamp is made possible by the burning time of the residual emitter amount. The power supply of the electrode coils are permanently connected to cold start lamps. In the case of warm start lamps, the power supply leads are connected after preheating the electrode filaments or through components connected in parallel to the filaments.
Gemäß einem besonders bevorzugten Ausführungsbeispiel der Erfindung sind die Stromzuführungen der Elektroden- wendein bei Kaltstartlampen mittels einer gemeinsamen Verbindungsleitung verbunden.According to a particularly preferred embodiment of the invention, the power supply lines of the electrode turn are connected in cold start lamps by means of a common connecting line.
Bei einem alternativen Ausführungsbeispiel sind die Stromzuführungen der Elektrodenwendeln mittels einer Ka- pazität (Kondensator) und/oder einer Induktivität miteinander verbunden. Vorzugsweise bildet die Induktivität bei dieser Variante einen Teil eines Übertragers zum Vorheizen der Elektrodenwendeln aus.In an alternative embodiment, the power supply lines of the electrode filaments are connected to each other by means of a capacitance (capacitor) and / or an inductance. In this variant, the inductance preferably forms part of a transformer for preheating the electrode filaments.
Als vorteilhaft hat es sich erwiesen, wenn eine der Elektrodenwendeln als Wendel mit höherer Lebensdauer ausgebildet ist. Dadurch wird ein gemeinsamer Bereich von zwei Ausfallverteilungen verhindert, so dass eine größere Ausfallsicherheit der Lampe erreicht wird.It has proven to be advantageous if one of the electrode filaments is designed as a spiral with a longer service life. As a result, a common area of two failure distributions is prevented, so that a greater reliability of the lamp is achieved.
Die Stromzuführungen zumindest einer der Elektrodenwendeln sind vorzugsweise in einer Glasperle eingebettet, die zumindest abschnittsweise mit einer Beschichtung versehen ist, die mindestens ein Metallhydrid, vorzugsweise Titanhydrid aufweist. Am Lebensdauerende der Niederdruckentladungslampe, nachdem das Emittermaterial aufgebraucht ist, geht die Lampe in einen Kaltkathodenbetrieb über, der einen Anstieg der Kathodenfallspannung und damit eine starke Erwärmung des Elektrodensystems zur Folge hat. Dieser Temperaturanstieg führt zu einem Zerfall des Titanhydrids, so dass Wasserstoff freigesetzt wird, der die Entladung im Entladungsgefäß aufgrund der ansteigenden Brennspannung der Lampe beendet.The power supply lines of at least one of the electrode coils are preferably embedded in a glass bead, which is provided at least in sections with a coating which has at least one metal hydride, preferably titanium hydride. At the end of life of the low-pressure discharge lamp, after the emitter material has been used up, the lamp goes into a cold cathode mode, the increase of the cathode drop voltage and thus a causes severe heating of the electrode system. This increase in temperature leads to a disintegration of the titanium hydride, so that hydrogen is released, which terminates the discharge in the discharge vessel due to the increasing burning voltage of the lamp.
Vorzugsweise ist in dem Resonanzkreis zumindest eine thermische Sicherung angeordnet, die bei Nichtzünden der Niederdruckentladungslampe den Resonanzkreis und damit weitere Zündversuche unterbricht. Zündet die Niederdruckentladungslampe aufgrund einer Störung nicht, beispielsweise weil diese keinen verwertbaren Emitter mehr aufweist und durch den Wasserstoff des Titanhydrids brennunfähig gemacht wurde und hat das Vorschaltgerät über einen definierten Zeitraum vergeblich Zündversuche unternommen, so steigt die Temperatur im Bereich der Thermosicherung an, wobei diese bei einer bestimmten Temperatur thermisch zerstört wird. Die Thermosicherung ist derart dimensioniert, dass die kritische Temperaturerhöhung nicht im normalen Betrieb der Lampe, beispielsweise beim Brennen im Downlight erreicht wird. Eine derartige thermische Sicherung kann beispielsweise als Sicherungswiderstand ausgebildet sein. Insbesondere bei hochohmigen Elektrodenwendeln kann durch diese kostengünstige Cut-Off-Technik die Effizienz der Lampe verbessert werden.Preferably, at least one thermal fuse is arranged in the resonant circuit, which interrupts the resonant circuit and thus further ignition attempts when the low-pressure discharge lamp is not ignited. If the low-pressure discharge lamp does not ignite due to a fault, for example because it no longer has a usable emitter and has been made incapable of firing by the hydrogen of the titanium hydride and the ballast has attempted to ignite unsuccessfully over a defined period of time, the temperature in the region of the thermal fuse increases thermally destroyed at a certain temperature. The thermal fuse is dimensioned such that the critical temperature increase is not achieved during normal operation of the lamp, for example when burning in the downlight. Such a thermal fuse may be formed, for example, as a fuse resistor. Especially with high-resistance electrode filaments, the efficiency of the lamp can be improved by this cost-effective cut-off technique.
Die thermische Sicherung ist bei einem erfindungsgemäßen Ausführungsbeispiel in Reihe zu einem Resonanzkondensator in dem Resonanzkreis angeordnet.The thermal fuse is arranged in an embodiment of the invention in series with a resonant capacitor in the resonant circuit.
Gemäß einer Weiterbildung der Erfindung weisen die Elektrodenwendeln jeweils zumindest zwei mit einem Emittermaterial versehene Wendelschenkel auf, die mittels zu- mindest eines elektrisch isolierten Wendelhalters derart lagefixiert sind, dass die Wendelschenkel einen Winkel von weniger als 180° zueinander und dadurch eine größere Wendellänge und damit eine größere Emittermenge aufwei- sen. Das heißt, die Elektrodenwendeln können bei gleicher Wickelgeometrie mehr Emittermenge aufnehmen. Da die Lebensdauer mit der Zunahme des Emittergewichts skaliert, kann dadurch eine wesentliche Lebensdauerverbesserung der Niederdruckentladungslampe erreicht werden. Des Weiteren wird eine Schädigung der emitterfreien Wendelenden durch Sputtern beim Kaltstart verringert, da sich die Schädigung auf mehrere Wendelenden verteilt. Aufgrund des über den Wendelhalter gehaltenen weiteren Wendelschenkels kann die Lampe selbst dann, wenn ein Wendelschenkel vollstän- dig zerstört ist, weiter betrieben werden.According to one development of the invention, the electrode filaments each have at least two filament legs provided with an emitter material, which are connected by means of At least one electrically insulated coil holder are fixed in position such that the coil legs at an angle of less than 180 ° to each other and thereby have a larger coil length and thus a larger emitter quantity. That is, the electrode filaments can accommodate more Emittermenge with the same winding geometry. As the life scales with the increase in the emitter weight, a substantial improvement in the life of the low-pressure discharge lamp can be achieved. Furthermore, damage to the emitter-free coil ends is reduced by sputtering during a cold start, since the damage is distributed over several coil ends. Due to the further helix limb held over the helix holder, the lamp can continue to operate even when a helix limb is completely destroyed.
Kurze Beschreibung der ZeichnungenBrief description of the drawings
Nachstehend wird die Erfindung anhand bevorzugter Ausführungsbeispiele näher erläutert. Es zeigen:The invention will be explained in more detail below with reference to preferred embodiments. Show it:
Figur 1 eine schematische Schaltungsanordnung gemäß eines ersten erfindungsgemäßen Ausführungsbeispiels undFigure 1 shows a schematic circuit arrangement according to a first embodiment of the invention and
Figur 2 eine schematische Schaltungsanordnung gemäß eines zweiten erfindungsgemäßen Ausführungsbeispiels.Figure 2 is a schematic circuit arrangement according to a second embodiment of the invention.
Bevorzugte Ausführungen der ErfindungPreferred embodiments of the invention
Figur 1 zeigt eine schematische Schaltungsanordnung 1 zum Betrieb zumindest einer als Leuchtstofflampe 2 ausgebildeten Niederdruckentladungslampe. Diese besitzt ein etwa stab- bzw. röhrenförmiges Entladungsgefäß 4 aus Glas, das auf der Innenseite mit einer nicht dargestellten LeuchtstoffSchicht versehen ist. Das Entladungsgefäß 4 hat einen beidseitig abgedichteten Entladungsraum 6, in den zwei Elektrodenwendeln 8, 10 ragen, die zur elektrischen Kontaktierung jeweils mit Stromzuführungen 12, 14 verbunden sind und einen Teil eines Resonanzkreises 16 ausbilden. Zwischen den Elektrodenwendeln 8, 10 bildet sich während des Lampenbetriebs eine Gasentladung in dem Entladungsgefäß 4 aus. Die beiden Stromzuführungen 12, 14 der Elektrodenwendeln 8, 10 sind jeweils elektrisch leitend miteinander verbunden, so dass der zum Erzeugen der Zündspannung der Leuchtstofflampe 2 erforderliche Resonanzkreis 16 auch nach einem schematisch angedeuteten Bruch der Elektrodenwendeln 8, 10 nicht unterbrochen ist. Dadurch kann die Leuchtstofflampe 2 nach einem Wendelbruch weiter betrieben werden, so dass das Emittermaterial der Elektrodenwendeln 8, 10 im Wesentlichen vollständig aufgebraucht wird und eine Lebensdauerverlängerung der Lampe 2 um die Brenndauer der Restemittermenge ermöglicht ist. Die Stromzuführungen 12, 14 der Elektrodenwendeln 8, 10 sind jeweils über eine Verbindungsleitung 18, 20 verbunden, an der die Zündspannung UB anliegt.FIG. 1 shows a schematic circuit arrangement 1 for operating at least one low-pressure discharge lamp designed as a fluorescent lamp 2. This one has about rod or tubular discharge vessel 4 made of glass, which is provided on the inside with a phosphor layer, not shown. The discharge vessel 4 has a discharge chamber 6 sealed on both sides, in which two electrode filaments 8, 10 protrude, which are each connected to power supply lines 12, 14 for electrical contacting and form part of a resonance circuit 16. Between the electrode coils 8, 10, a gas discharge is formed in the discharge vessel 4 during lamp operation. The two power supply lines 12, 14 of the electrode coils 8, 10 are each electrically conductively connected to each other, so that the time required to generate the ignition voltage of the fluorescent lamp 2 resonant circuit 16 is not interrupted even after a schematically indicated fraction of the electrode coils 8, 10. As a result, the fluorescent lamp 2 can continue to be operated after a spiral break, so that the emitter material of the electrode coils 8, 10 is essentially completely used up and a service life extension of the lamp 2 by the burning time of the residual emitter quantity is made possible. The power supply lines 12, 14 of the electrode coils 8, 10 are each connected via a connecting line 18, 20, at which the ignition voltage U B is present.
Bei einem alternativen, nicht dargestellten Ausführungsbeispiel sind die Stromzuführungen 12, 14 der Elektrodenwendeln 8, 10 mittels eines Kondensators, einer Spule oder einer Serienschaltung aus Kondensator und Spule miteinander verbunden. Eine Spule bildet bei dieser Vari- ante einen Teil eines Übertragers zum Vorheizen der E- lektrodenwendeln aus. Die Stromzuführungen 12, 14 der Elektrodenwendeln 8, 10 sind innerhalb des Entladungsgefäßes 4 in einer nicht dargestellten Glasperle eingebettet, die mit einer Be- schichtung aus Titanhydrid und einem rheologischen Addi- tiv versehen ist. Am Lebensdauerende der Leuchtstofflampe 2, nachdem die Wendeln 8, 10 in der Regel gebrochen und das Emittermaterial vollständig aufgebraucht ist, geht die diese in einen Kaltkathodenbetrieb über, der einen Anstieg der Kathodenfallspannung und damit eine starke Erwärmung des Elektrodensystems zur Folge hat. Dieser Temperaturanstieg führt zu einem Zerfall des Titanhydrids, so dass Wasserstoff freigesetzt wird, der die Entladung im Entladungsgefäß 4 aufgrund der ansteigenden Brennspannung der Lampe 2 beendet. Um anschließend den Resonanzkreis 16 und damit weitere Zündversuche zu unterbrechen, ist in dem Resonanzkreis 16 eine thermische Sicherung 22 in Reihe zu einem Resonanzkondensator 24 angeordnet. Zündet die Leuchtstofflampe 2 nicht, weil diese keinen verwertbaren Emitter mehr aufweist und durch den Wasserstoff des Titanhydrids brennunfähig gemacht wurde, so steigt die Temperatur im Bereich der Thermosicherung 22 nach einer definierten Anzahl vergeblicher Zündversuche an, wobei diese bei einer bestimmten Temperatur thermisch zerstört wird. Die Thermosicherung 22 ist derart dimensioniert, dass die kritische Temperaturerhöhung nicht im normalen Betrieb der Lampe 2, beispielsweise beim Brennen im Downlight, erreicht wird. Eine derartige thermische Sicherung 22 kann beispielsweise als Sicherungswiderstand ausgebildet sein. Insbesondere bei hoch- ohmigen Elektrodenwendeln 8, 10 kann die Effizienz der Lampe 2 durch diese kostengünstige Cut-Off-Technik verbessert werden. Bei einem nicht dargestellten Ausführungsbeispiel weisen die Elektrodenwendeln 8, 10 jeweils zwei mit einem Emittermaterial versehene Wendelschenkel auf, die mittels eines elektrisch isolierten Wendelhalters derart in dem Entladungsgefäß 4 lagefixiert sind, dass die Wendelschenkel einen Winkel von etwa 80° zueinander und dadurch eine größere Wendellänge und damit eine größere Emittermenge aufweisen. Da die Lebensdauer mit der Zunahme des Emittergewichts skaliert, kann dadurch eine weitere Lebens- dauerverbesserung der Leuchtstofflampe 2 erreicht werden.In an alternative, not shown embodiment, the power supply lines 12, 14 of the electrode coils 8, 10 are connected to each other by means of a capacitor, a coil or a series circuit of capacitor and coil. In this variant, a coil forms part of a transformer for preheating the electrode coils. The power supply lines 12, 14 of the electrode coils 8, 10 are embedded within the discharge vessel 4 in a glass bead, not shown, which is provided with a coating of titanium hydride and a rheological additive. At the end of the life of the fluorescent lamp 2, after the coils 8, 10 are broken and the emitter material is completely used up, the latter changes into a cold cathode mode, which results in an increase in the cathode drop voltage and thus in a strong heating of the electrode system. This increase in temperature leads to a disintegration of the titanium hydride, so that hydrogen is released, which ends the discharge in the discharge vessel 4 due to the increasing burning voltage of the lamp 2. In order subsequently to interrupt the resonance circuit 16 and thus further ignition attempts, a thermal fuse 22 is arranged in series with a resonance capacitor 24 in the resonance circuit 16. If the fluorescent lamp 2 does not ignite because it no longer has a usable emitter and has been rendered incapable of burning by the hydrogen of the titanium hydride, the temperature in the region of the thermal fuse 22 increases after a defined number of futile ignition attempts, whereby it is thermally destroyed at a certain temperature. The thermal fuse 22 is dimensioned such that the critical temperature increase is not achieved during normal operation of the lamp 2, for example, when burning in the downlight. Such a thermal fuse 22 may be formed, for example, as a fuse resistor. In particular with high-resistance electrode filaments 8, 10, the efficiency of the lamp 2 can be improved by this cost-effective cut-off technique. In one embodiment, not shown, the electrode coils 8, 10 each have two provided with an emitter material filament legs, which are fixed in position in the discharge vessel 4 by means of an electrically insulated coil holder such that the filament legs at an angle of about 80 ° to each other and thereby a greater coil length and thus have a larger amount of emitters. As the service life scales with the increase in the emitter weight, a further improvement in the life of the fluorescent lamp 2 can be achieved.
Figur 2 zeigt eine erfindungsgemäße Schaltungsanordnung 1 gemäß eines weiteren Ausführungsbeispiels, das sich von dem vorbeschriebenen Ausführungsbeispiel im We- sentlichen dadurch unterscheidet, dass die in Figur 2 linke Elektrodenwendel 8 als Wendel mit höherer Lebensdauer und Ausfallsicherheit ausgebildet ist, deren Stromzuführungen 12, 14 nicht elektrisch miteinander verbunden sind. Aufgrund der Wendel 8 mit höherer Lebensdauer wird ein gemeinsamer Bereich von zwei Ausfallverteilungen der Wendeln 8, 10 verhindert, so dass eine größere Ausfallsicherheit erreicht wird. Die Stromzuführungen 12, 14 der rechten Elektrodenwendel 10 sind elektrisch leitend über die Verbindungsleitung 20 miteinander verbunden, so dass der zum Erzeugen der Zündspannung der Leuchtstofflampe 2 erforderliche Resonanzkreis 16 auch nach einem schematisch angedeuteten Bruch der Elektrodenwendel 10 nicht unterbrochen ist. Dadurch kann die Leuchtstofflampe 2 nach einem Wendelbruch der Wendel 10 weiter betrieben werden, so dass das Emittermaterial der Elektrodenwendeln 8, 10 im Wesentlichen vollständig aufgebraucht und eine Lebensdauerverlängerung der Lampe 2 erreicht wird. Die Einkopplung der Zündspannung UB erfolgt bei diesem Aus- führungsbeispiel vorzugsweise auf der dem Resonanzkreis 16 gegenüberliegenden Seite der Schaltungsanordnung 1.Figure 2 shows a circuit arrangement according to the invention 1 according to a further embodiment, which differs from the above-described embodiment essentially in that the left in Figure 2 electrode coil 8 is formed as a helix with longer life and reliability, the power supply lines 12, 14 is not electrically connected to each other. Due to the coil 8 with a longer service life, a common area of two failure distributions of the coils 8, 10 is prevented, so that greater reliability is achieved. The power supply lines 12, 14 of the right-hand electrode coil 10 are connected to one another in an electrically conductive manner via the connecting line 20, so that the resonant circuit 16 required for generating the ignition voltage of the fluorescent lamp 2 is not interrupted even after a schematically indicated rupture of the electrode coil 10. As a result, the fluorescent lamp 2 can continue to be operated after a helical break of the helix 10, so that the emitter material of the electrode helices 8, 10 is essentially completely used up and a service life extension of the lamp 2 is achieved. The coupling of the ignition voltage U B takes place at this output Guidance example preferably on the opposite side of the resonant circuit 16 of the circuit arrangement. 1
Die erfindungsgemäße Schaltungsanordnung 1 ist nicht auf den beschriebenen Resonanzkreis 16 beschränkt, vielmehr kann die Kontaktierung der Elektrodenwendeln 8, 10 mit der Zündspannung UB und deren Einkopplung auf unterschiedliche aus dem Stand der Technik bekannte Weise erfolgen .The circuit arrangement 1 according to the invention is not limited to the described resonant circuit 16, but the contacting of the electrode filaments 8, 10 with the ignition voltage U B and their coupling can be carried out in different manner known from the prior art.
Offenbart ist eine Schaltungsanordnung 1 zum Betrieb zumindest einer Niederdruckentladungslampe 2, insbesondere einer Leuchtstofflampe oder Kompaktleuchtstofflampe, mit zumindest zwei Elektrodenwendeln 8, 10, die jeweils mit Stromzuführungen 12, 14 verbunden sind und einen Teil eines Resonanzkreises 16 ausbilden. Erfindungemäß sind die Stromzuführungen 12, 14 zumindest einer der Elektrodenwendeln 8, 10 mittelbar oder unmittelbar elektrisch leitend miteinander verbunden oder verbindbar. Disclosed is a circuit arrangement 1 for operating at least one low-pressure discharge lamp 2, in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode coils 8, 10 which are each connected to power supply lines 12, 14 and form part of a resonant circuit 16. According to the invention, the power supply lines 12, 14 of at least one of the electrode coils 8, 10 are connected or connectable to one another directly or indirectly in an electrically conductive manner.

Claims

Ansprüche claims
1. Schaltungsanordnung zum Betrieb zumindest einer Niederdruckentladungslampe (2), insbesondere einer Leuchtstofflampe oder Kompaktleuchtstofflampe, mit zumin- dest zwei Elektrodenwendeln (8, 10), die jeweils mit Stromzuführungen (12, 14) verbunden sind und einen Teil eines Resonanzkreises (16) ausbilden, dadurch gekennzeichnet, dass die Stromzuführungen (12, 14) zumindest einer der Elektrodenwendeln (8, 10) elektrisch leitend mittelbar oder unmittelbar miteinander verbunden oder verbindbar sind.1. Circuit arrangement for operating at least one low-pressure discharge lamp (2), in particular a fluorescent lamp or compact fluorescent lamp, with at least two electrode coils (8, 10) which are each connected to power supply lines (12, 14) and form part of a resonant circuit (16) , characterized in that the power supply lines (12, 14) of at least one of the electrode coils (8, 10) electrically conductively directly or indirectly connected or connectable.
2. Schaltungsanordnung nach Anspruch 1, wobei die Stromzuführungen (12, 14) der zumindest einen Elektroden- wendel (8, 10) mittels einer Verbindungsleitung (18, 20) verbunden sind.2. Circuit arrangement according to claim 1, wherein the power supply lines (12, 14) of the at least one electrode coil (8, 10) by means of a connecting line (18, 20) are connected.
3. Schaltungsanordnung nach Anspruch 1, wobei die Stromzuführungen (12, 14) der zumindest einen Elektroden- wendel (8, 10) mittels mindestens einer Kapazität und/oder einer Induktivität verbunden sind.3. Circuit arrangement according to claim 1, wherein the power supply lines (12, 14) of the at least one electrode coil (8, 10) are connected by means of at least one capacitor and / or an inductance.
4. Schaltungsanordnung nach Anspruch 3, wobei die Induktivität einen Teil eines Übertragers zum Vorheizen der Elektrodenwendel (8, 10) bildet.4. Circuit arrangement according to claim 3, wherein the inductance forms part of a transformer for preheating the electrode coil (8, 10).
5. Schaltungsanordnung nach einem der vorhergehenden Ansprüche, wobei eine der Elektrodenwendeln (8) als Wendel mit höherer Lebensdauer ausgebildet ist. 5. Circuit arrangement according to one of the preceding claims, wherein one of the electrode coils (8) is designed as a helix with a longer service life.
6. Schaltungsanordnung nach einem der vorhergehenden Ansprüche, wobei in dem Resonanzkreis (16) zumindest eine thermische Sicherung (22) angeordnet ist, die bei Nicht- zünden der Niederdruckentladungslampe (2) den Resonanz- kreis (16) unterbricht.6. Circuit arrangement according to one of the preceding claims, wherein in the resonant circuit (16) at least one thermal fuse (22) is arranged, which interrupts the non-ignition of the low-pressure discharge lamp (2) the resonant circuit (16).
7. Schaltungsanordnung nach Anspruch 6, wobei die thermische Sicherung (22) zumindest einen Sicherungswiderstand aufweist.7. Circuit arrangement according to claim 6, wherein the thermal fuse (22) has at least one fuse resistor.
8. Schaltungsanordnung nach Anspruch 6 oder 7, wobei die thermische Sicherung (22) in Reihe zu einem Resonanzkondensator (24) in dem Resonanzkreis (16) angeordnet ist.8. Circuit arrangement according to claim 6 or 7, wherein the thermal fuse (22) is arranged in series with a resonance capacitor (24) in the resonant circuit (16).
9. Schaltungsanordnung nach einem der vorhergehenden Ansprüche, wobei die Stromzuführungen (12, 14) zumindest einer der Elektrodenwendeln (8, 10) in einer Glasperle eingebettet sind, die zumindest abschnittsweise mit einer Beschichtung versehen ist, die mindestens ein Metallhydrid, vorzugsweise Titanhydrid aufweist.9. Circuit arrangement according to one of the preceding claims, wherein the power supply lines (12, 14) at least one of the electrode coils (8, 10) are embedded in a glass bead, which is at least partially provided with a coating having at least one metal hydride, preferably titanium hydride.
10. Schaltungsanordnung nach einem der vorhergehenden Ansprüche, wobei die Elektrodenwendeln (8, 10) jeweils zumindest zwei mit einem Emittermaterial versehene Wendelschenkel aufweisen, die mittels mindestens eines e- lektrisch isolierten Wendelhalters derart lagefixiert sind, dass die Wendelschenkel einen Winkel von weniger als 180° zueinander aufweisen. 10. Circuit arrangement according to one of the preceding claims, wherein the electrode filaments (8, 10) each have at least two provided with an emitter material filament legs, which are fixed in position by means of at least one electrically insulated coil holder such that the filament legs an angle of less than 180 ° to each other.
PCT/EP2007/061228 2006-11-03 2007-10-19 Circuit arrangement for low-pressure discharge lamps WO2008052893A1 (en)

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WO2008052894A2 (en) * 2006-11-03 2008-05-08 Osram Gesellschaft mit beschränkter Haftung Low-pressure discharge lamp

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EP1416517A2 (en) * 2002-10-31 2004-05-06 Murata Manufacturing Co., Ltd. Fluorescent lamp lighting device
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Publication number Priority date Publication date Assignee Title
US4949013A (en) * 1988-02-22 1990-08-14 Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen M.B.H. High-frequency operating circuit for a fluorescent lamp
US20020011791A1 (en) * 2000-05-10 2002-01-31 Hiroki Nakagawa Fluorescent lamp lighting apparatus
US20040041524A1 (en) * 2001-05-23 2004-03-04 Maurizio Menna Fluorescent lamp circuit
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008052894A2 (en) * 2006-11-03 2008-05-08 Osram Gesellschaft mit beschränkter Haftung Low-pressure discharge lamp
WO2008052894A3 (en) * 2006-11-03 2008-12-11 Osram Gmbh Low-pressure discharge lamp

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