EP0330118A2 - Drive circuitry for a low-pressure discharge lamp - Google Patents

Drive circuitry for a low-pressure discharge lamp Download PDF

Info

Publication number
EP0330118A2
EP0330118A2 EP89102899A EP89102899A EP0330118A2 EP 0330118 A2 EP0330118 A2 EP 0330118A2 EP 89102899 A EP89102899 A EP 89102899A EP 89102899 A EP89102899 A EP 89102899A EP 0330118 A2 EP0330118 A2 EP 0330118A2
Authority
EP
European Patent Office
Prior art keywords
circuit
electrode
push
pressure discharge
discharge lamp
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Withdrawn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
EP89102899A
Other languages
German (de)
French (fr)
Other versions
EP0330118A3 (en
Inventor
Anton Zuchtriegel
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 EP0330118A2 publication Critical patent/EP0330118A2/en
Publication of EP0330118A3 publication Critical patent/EP0330118A3/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14Circuit arrangements
    • H05B41/26Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
    • H05B41/28Circuit 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
    • H05B41/295Circuit 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
    • H05B41/298Arrangements for protecting lamps or circuits against abnormal operating conditions
    • H05B41/2981Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the circuit against abnormal operating conditions
    • H05B41/2985Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the circuit against abnormal operating conditions against abnormal lamp operating conditions
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S315/00Electric lamp and discharge devices: systems
    • Y10S315/05Starting and operating circuit for fluorescent lamp

Definitions

  • the invention relates to a circuit arrangement for high-frequency operation of a low-pressure discharge lamp in accordance with the preamble of claim 1.
  • the object of the invention is to achieve a further simplification of the circuit arrangement with regard to the reclosure after the low-pressure discharge lamp has been replaced.
  • the new connection of the electrode does not direct the direct current from the power supply unit directly to the push-pull generator, but first flows through an electrode coil of the lamp, which can be arranged either between the positive or the negative poles of the circuit.
  • the circuit is therefore interrupted if there is no lamp in the socket or if there is a filament break in the designated filament.
  • the push-pull oscillator is thus de-energized and the shutdown circuit is not active, i.e. no power loss is consumed in the holding circuit. If an intact lamp is then plugged in, the corresponding filament of the lamp closes the circuit.
  • the required DC operating voltage can build up on the push-pull generator because the shutdown circuit is deactivated. The low-pressure discharge lamp is thus started again automatically.
  • attaching the electrode between the mains rectifier and push-pull generator offers the possibility of achieving increased preheating of the filament by means of the direct current flow.
  • a diode is connected in parallel with the electrode filament arranged between the mains rectifier and the push-pull generator. As a result, the preheating current on this coil is reduced to half the value.
  • the block diagram in FIG. 1 shows the basic structure of a circuit arrangement according to the invention for a low-pressure discharge lamp LP.
  • the circuit arrangement includes a high-frequency filter 1, a mains rectifier 2 and a push-pull frequency generator 3 with a series resonance circuit and a shutdown device.
  • the lamp LP has two electrodes E1 and E2, the two connections of the electrode E1 being connected to the push-pull generator 3.
  • the electrode E2 is connected with its one connection to the positive pole of the mains rectifier 2 and with its other connection to the input of the push-pull frequency generator 3.
  • a harmonic filter 4 is featured see that is connected between the positive pole of the rectifier 2 and the corresponding connection of the electrode E2.
  • FIG. 2 shows the exact circuit diagram of a circuit arrangement with a reclosing device according to the invention for operating a low-pressure discharge lamp.
  • a block of a current-compensated filter choke FD and a filter capacitor C1 are connected in parallel to the input of the line rectifier GL in each supply line.
  • the line rectifier GL follows this high-frequency filter and, in parallel, the push-pull frequency generator.
  • the self-regulating push-pull frequency generator consists of the two transistors T1, T2 with the same polarity and the reverse current diodes D3, D4, the series resistors R5 to R8, the control transformer and the starting generator with the resistors R4, R9, the starting capacitor C3, the diode D1 and the diac DC.
  • the control transformer works on the feedback principle and consists of the primary winding RK1.1 and the two secondary windings RK1.2 and RK1.3.
  • the lamp LP is connected by a connection of the electrode E1 to the center tap M1 between the two transistors T1, T2 and by a connection of the other electrode E2 to the positive pole of the mains rectifier GL.
  • a series resonance circuit comprising resonance inductance L1, coupling capacitor C7 and resonance capacitor C8 is provided, the resonance inductance L1 and the coupling capacitor C7 between the primary winding RK1.1 of the control transformer and the corresponding connection of the electrode E1 and the resonance capacitor C8 between the connections on the heating circuit side Electrodes E1 and E2 are switched.
  • a smoothing capacitor C2 In addition to the switching paths of the transistors T1, T2 there is a smoothing capacitor C2.
  • the circuit arrangement also has an active harmonic filter.
  • the filter consists of two diodes D5, D6 connected in series and in the forward DC direction to the positive pole of the power rectifier GL, the center tap M2 between the two diodes D5, D6 being connected via a capacitor C4 to the center tap M1 between the two transistors T1, T2.
  • the harmonic filter also contains two further diodes D7, D8 connected in series and in the forward DC direction, the center tap M3 between these two diodes D7, D8 via a capacitor C5 also with the center tap M1 between the two transistors T1, T2 and a capacitor C6 to the tap M4 between the resonance inductor L1 and the coupling capacitor C7.
  • the capacitor C6 also serves as a resonance capacitor if the heating current through the PTC thermistor KL has been reduced after the electrodes have been preheated.
  • the capacitors of the harmonic filter continuously pump energy into the smoothing capacitor C2, so that a sinusoidal mains current consumption is guaranteed. More detailed information on the mode of operation of the harmonic filter can be found in DE-OS 36 23 749.
  • the circuit arrangement therefore additionally has a switch-off device with trigger control.
  • This consists of a series connection of a diode D2, a resistor R2 and a thyristor TH, which connects the base of the transistor T1 to the negative pole of the mains rectifier GL.
  • the center tap M5 is connected between the resistor R2 and the thyristor TH via a resistor R1 to the positive pole of the smoothing capacitor C2.
  • the trigger control consists of the two Zener diodes DZ1, DZ2, which connect the gate of the thyristor TH to the positive pole of the smoothing capacitor C2, and of the resistor R3, which connects the gate of the thyristor TH to its cathode.
  • the two Zener diodes DZ1 and DZ2 become conductive with the same total breakdown voltage and thus trigger the turn-off thyristor TH.
  • the control energy is thus withdrawn from the base of the transistor T1 by dissipation to the negative pole of the mains rectifier GL; the transistor is blocked and the resonance circuit of inductance L1, capacitor C7 and capacitor C8 is de-energized.
  • the thyristor TH is kept in the conductive state, so that any renewed use of vibrations is prevented.
  • the diode D2 blocks the AC voltage from the anode circuit of the thyristor TH.
  • the electrode E2 is arranged between the diode D6 and D8 of the harmonic filter and the positive input of the transistor T1 of the push-pull generator.
  • the two current connections of the electrode E2 are also bridged by a diode D9 in the direct current blocking direction.
  • the electrodes are preheated by the construction of the circuit arrangement. However, this preheating is uneven, since the electrode E2 is inserted between the power supply and generator part, and this electrode is preheated due to the direct current flow. With the help of the diode, the preheating current of the preheating circuit on this coil is reduced to half the value, so that both electrodes are subjected to approximately the same load.

Abstract

In the circuit arrangement for high-frequency operation of a low-]pressure discharge lamp (LP), having a mains rectifier (2) and a push-pull frequency generator (3) with a series-resonant circuit and a switch-off device, the electrode (E2) connected to the positive or negative terminal of the mains rectifier (2) is connected between the mains rectifier (2) and the push-pull frequency generator (3). As a result of this connection of the electrode (E2), when the low-pressure discharge lamp (LP) is replaced, the circuit is interrupted and the switch-off circuit is inhibited. On insertion of a new lamp, the circuit is closed again so that the low-pressure discharge lamp (LP) can be started automatically again by means of the push-pull frequency generator (3). <IMAGE>

Description

Die Erfindung betrifft eine Schaltungsanordnung zum hochfrequenten Betrieb einer Niederdruckentladungs­lampe entsprechend dem Oberbegriff des Anspruchs 1.The invention relates to a circuit arrangement for high-frequency operation of a low-pressure discharge lamp in accordance with the preamble of claim 1.

In der deutschen Patentanmeldung P 37 00 421.2 ist eine solche Schaltungsanordnung mit Abschaltvorrich­tung zum Betrieb einer Niederdruckentladungslampe vorgeschlagen. Bei Auftritt eines Lampenfehlers wird der Gegentaktfrequenzgenerator durch den Thyristor der Abschaltvorrichtung außer Funktion gesetzt. Damit der Gegentaktfrequenzgenerator nach dem Einsatz einer neuen Entladungslampe wieder anlaufen kann, muß die Schaltungsanordnung zuerst ausgeschaltet und nach ca. 5 sec. wieder eingeschaltet werden.In the German patent application P 37 00 421.2, such a circuit arrangement with a switch-off device for operating a low-pressure discharge lamp is proposed. If a lamp error occurs, the push-pull frequency generator is deactivated by the thyristor of the shutdown device. So that the push-pull frequency generator can start up again after the use of a new discharge lamp, the circuit arrangement must first be switched off and then switched on again after about 5 seconds.

Andererseits ist aus der DE-OS 36 08 615 eine Schal­tungsanordnung bekannt, die zusätzlich zu der Ab­schaltvorrichtung eine Wiedereinschaltvorrichtung aus einem Kondensator und einem Widerstand aufweist. Bei Einsatz einer neuen intakten Niederdruckentladungs­lampe wird die positiv aufgeladene Fläche des Konden­sators mit dem Minuspol verbunden. Dadurch wird eine Umladung des Kondensators in Gang gesetzt, die dem Thyristor der Abschaltvorrichtung den Haltestrom entzieht und ihn in den Sperrzustand versetzt, so daß der Gegentaktgenerator ohne Abschalten der Schaltungs­anordnung wieder anlaufen kann.On the other hand, from DE-OS 36 08 615 a circuit arrangement is known which, in addition to the switch-off device, has a restart device consisting of a capacitor and a resistor. When a new intact low-pressure discharge lamp is used, the positively charged surface of the capacitor is connected to the negative pole. This initiates a charge reversal of the capacitor, which withdraws the holding current from the thyristor of the switch-off device and puts it into the blocking state, so that the push-pull generator can start up again without switching off the circuit arrangement.

Aufgabe der Erfindung ist es, eine weitere Verein­fachung der Schaltungsanordnung in bezug auf die Wiedereinschaltung nach Auswechseln der Niederdruck­entladungslampe zu erreichen.The object of the invention is to achieve a further simplification of the circuit arrangement with regard to the reclosure after the low-pressure discharge lamp has been replaced.

Diese Aufgabe wird durch die kennzeichnenden Merkmale des 1. Anspruchs gelöst. Eine weitere vorteilhafte Ausgestaltung der Schaltungsanordnung ist dem Unter­anspruch zu entnehmen.This object is achieved by the characterizing features of the first claim. A further advantageous embodiment of the circuit arrangement can be found in the subclaim.

Durch die neue Verschaltung der Elektrode wird der Gleichstrom vom Netzteil nicht direkt an den Gegen­taktgenerator geleitet, sondern durchfließt zuerst eine Elektrodenwendel der Lampe, die entweder zwischen den positiven oder den negativen Polen der Schaltung angeordnet sein kann. Der Stromkreis wird daher unter­brochen, wenn sich keine Lampe in der Fassung befindet oder ein Wendelbruch bei der bezeichneten Wendel vor­liegt. Damit ist der Gegentaktschwinger spannungslos und der Abschaltkreis nicht aktiv, d.h. es wird keine Verlustleistung im Haltestromkreis verbraucht. Wird anschließend eine intakte Lampe eingesteckt, so schließt die entsprechende Wendel der Lampe den Strom­kreis. Am Gegentaktgenerator kann sich die erforder­liche Betriebsgleichspannung aufbauen, da der Ab­schaltkreis außer Funktion gesetzt ist. Die Nieder­druckentladungslampe wird somit selbsttätig wieder gestartet.The new connection of the electrode does not direct the direct current from the power supply unit directly to the push-pull generator, but first flows through an electrode coil of the lamp, which can be arranged either between the positive or the negative poles of the circuit. The circuit is therefore interrupted if there is no lamp in the socket or if there is a filament break in the designated filament. The push-pull oscillator is thus de-energized and the shutdown circuit is not active, i.e. no power loss is consumed in the holding circuit. If an intact lamp is then plugged in, the corresponding filament of the lamp closes the circuit. The required DC operating voltage can build up on the push-pull generator because the shutdown circuit is deactivated. The low-pressure discharge lamp is thus started again automatically.

Als weiteren Vorteil bietet die Anbringung der Elek­trode zwischen Netzgleichrichter und Gegentaktgene­rator die Möglichkeit, durch den Gleichstromdurchfluß eine verstärkte Vorheizung der Wendel zu erreichen. Um auch bei Schaltungsanordnungen mit höherer Aus­ gangsleistung zum Betrieb von Niederdruckentladungs­lampen mit Leistungsaufnahmen größer 30 W eine gleich­mäßige Belastung der beiden Elektrodenwendeln durch den Vorheizstrom zu erzielen, ist parallel zu der zwischen dem Netzgleichrichter und dem Gegentakt­generator angeordneten Elektrodenwendel eine Diode in Gleichstromsperrichtung geschaltet. Dadurch wird der Vorheizstrom an dieser Wendel auf den halben Wert herabgesetzt.As a further advantage, attaching the electrode between the mains rectifier and push-pull generator offers the possibility of achieving increased preheating of the filament by means of the direct current flow. To even with circuit arrangements with higher off to achieve a uniform loading of the two electrode filaments by the preheating current, a diode is connected in parallel with the electrode filament arranged between the mains rectifier and the push-pull generator. As a result, the preheating current on this coil is reduced to half the value.

Die Erfindung ist durch die nachfolgenden Figuren näher veranschaulicht.

  • Figur 1 zeigt das Blockschaltbild einer erfindungs­gemäßen Schaltungsanordnung für eine Nieder­druckentladungslampe
  • Figur 2 zeigt das vollständige Schaltbild einer er­findungsgemäßen Schaltungsanordnung zum Betrieb einer Niederdruckentladungslampe
The invention is illustrated in more detail by the following figures.
  • FIG. 1 shows the block diagram of a circuit arrangement according to the invention for a low-pressure discharge lamp
  • FIG. 2 shows the complete circuit diagram of a circuit arrangement according to the invention for operating a low-pressure discharge lamp

Das Blockschaltbild in Figur 1 gibt den Prinzipaufbau einer erfindungsgemäßen Schaltungsanordnung für eine Niederdruckentladungslampe LP wieder. Die Schaltungs­anordnung beinhaltet ein Hochfrequenzfilter 1, einen Netzgleichrichter 2 und einen Gegentaktfrequenzgene­rator 3 mit Serienresonanzkreis und Abschaltvorrich­tung. Die Lampe LP weist zwei Elektroden E1 und E2 auf, wobei die beiden Anschlüsse der Elektrode E1 mit dem Gegentaktgenerator 3 verbunden sind. Die Elektrode E2 ist mit ihrem einen Anschluß mit dem Pluspol des Netzgleichrichters 2 und mit ihrem anderen Anschluß mit dem Eingang des Gegentaktfrequenzgenerators 3 verbunden. Außerdem ist ein Oberwellenfilter 4 vorge­ sehen, das zwischen den Pluspol des Netzgleichrich­ters 2 und den entsprechenden Anschluß der Elektrode E2 geschaltet ist.The block diagram in FIG. 1 shows the basic structure of a circuit arrangement according to the invention for a low-pressure discharge lamp LP. The circuit arrangement includes a high-frequency filter 1, a mains rectifier 2 and a push-pull frequency generator 3 with a series resonance circuit and a shutdown device. The lamp LP has two electrodes E1 and E2, the two connections of the electrode E1 being connected to the push-pull generator 3. The electrode E2 is connected with its one connection to the positive pole of the mains rectifier 2 and with its other connection to the input of the push-pull frequency generator 3. In addition, a harmonic filter 4 is featured see that is connected between the positive pole of the rectifier 2 and the corresponding connection of the electrode E2.

Figur 2 zeigt das genaue Schaltbild einer Schaltungs­anordnung mit erfindungsgemäßer Wiedereinschaltvor­richtung zum Betrieb einer Niederdruckentladungslampe. Direkt an den Netzeingang ist in jede Zuleitung ein Block einer stromkompensierten Filterdrossel FD sowie parallel zum Eingang des Netzgleichrichters GL ein Filterkondensator C1 geschaltet. Diesem Hochfrequenz­filter folgt der Netzgleichrichter GL sowie parallel dazu der Gegentaktfrequenzgenerator. Der selbststeu­ernde Gegentaktfrequenzgenerator besteht aus den beiden gleichsinnig gepolten Transistoren T1, T2 mit den Rückstromdioden D3, D4, den Vorschaltwiderständen R5 bis R8, dem Steuerübertrager und dem Anlaufgene­rator mit den Widerständen R4, R9, dem Startkonden­sator C3, der Diode D1 sowie dem Diac DC. Der Steuer­übertrager arbeitet nach dem Rückkopplungsprinzip und setzt sich aus der Primärwicklung RK1.1 sowie den beiden Sekundärwicklungen RK1.2 und RK1.3 zusammen. Die Lampe LP ist mit einem Anschluß der Elektrode E1 mit dem Mittenabgriff M1 zwischen den beiden Transi­storen T1, T2 und mit einem Anschluß der anderen Elektrode E2 mit dem Pluspol des Netzgleichrichters GL verbunden. Außerdem ist ein Serienresonanzkreis aus Resonanzinduktivität L1, Koppelkondensator C7 und Resonanzkondensator C8 vorgesehen, wobei die Resonanz­induktivität L1 und der Koppelkondensator C7 zwischen die Primärwicklung RK1.1 des Steuerübertragers und den entsprechenden Anschluß der Elektrode E1 und der Resonanzkondensator C8 zwischen die auf der Heizkreis­seite liegenden Anschlüsse der Elektroden E1 und E2 geschaltet sind. Parallel zu den Schaltstrecken der Transistoren T1, T2 liegt außerdem ein Glättungs­kondensator C2.FIG. 2 shows the exact circuit diagram of a circuit arrangement with a reclosing device according to the invention for operating a low-pressure discharge lamp. A block of a current-compensated filter choke FD and a filter capacitor C1 are connected in parallel to the input of the line rectifier GL in each supply line. The line rectifier GL follows this high-frequency filter and, in parallel, the push-pull frequency generator. The self-regulating push-pull frequency generator consists of the two transistors T1, T2 with the same polarity and the reverse current diodes D3, D4, the series resistors R5 to R8, the control transformer and the starting generator with the resistors R4, R9, the starting capacitor C3, the diode D1 and the diac DC. The control transformer works on the feedback principle and consists of the primary winding RK1.1 and the two secondary windings RK1.2 and RK1.3. The lamp LP is connected by a connection of the electrode E1 to the center tap M1 between the two transistors T1, T2 and by a connection of the other electrode E2 to the positive pole of the mains rectifier GL. In addition, a series resonance circuit comprising resonance inductance L1, coupling capacitor C7 and resonance capacitor C8 is provided, the resonance inductance L1 and the coupling capacitor C7 between the primary winding RK1.1 of the control transformer and the corresponding connection of the electrode E1 and the resonance capacitor C8 between the connections on the heating circuit side Electrodes E1 and E2 are switched. In addition to the switching paths of the transistors T1, T2 there is a smoothing capacitor C2.

Die Funktionsweise einer solchen Schaltungsanordnung mit Gegentaktfrequenzgenerator und Serienresonanz­kreis zum Zünden und Betrieb einer Niederdruckentla­dungslampe kann dem Buch "Elektronikschaltungen" von W. Hirschmann (Siemens AG), 1982, Seite 148, entnommen werden und soll hier nicht näher ausgeführt werden. Der zusätzlich zum Resonanzkondensator C8 in Reihe geschaltete Kaltleiter KL reduziert den Heizstrom (auf ca. ein Zehntel), wenn eine ausreichende Vorheizung der Elektroden erfolgt ist.The mode of operation of such a circuit arrangement with push-pull frequency generator and series resonance circuit for igniting and operating a low-pressure discharge lamp can be found in the book "Electronics Circuits" by W. Hirschmann (Siemens AG), 1982, page 148, and is not to be described in more detail here. The PTC thermistor KL connected in series with the resonance capacitor C8 reduces the heating current (to about a tenth) if the electrodes have been preheated sufficiently.

Die Schaltungsanordnung weist weiterhin ein aktives Oberwellenfilter auf. Das Filter besteht aus zwei in Reihe und in Gleichstromvorwärtsrichtung am Pluspol des Netzgleichrichters GL angeschlossenen Dioden D5, D6, wobei der Mittenabgriff M2 zwischen den beiden Dioden D5, D6 über einen Kondensator C4 mit dem Mittenabgriff M1 zwischen den beiden Transistoren T1, T2 verbunden ist. Das Oberwellenfilter beinhaltet außerdem parallel zu den ersten beiden Dioden D5, D6 zwei weitere in Reihe und in Gleichstromvorwärtsrich­tung geschaltete Dioden D7, D8, wobei der Mittenab­griff M3 zwischen diesen beiden Dioden D7, D8 über einen Kondensator C5 ebenfalls mit dem Mittenabgriff M1 zwischen den beiden Transistoren T1, T2 und über einen Kondensator C6 mit dem Abgriff M4 zwischen der Resonanzinduktivität L1 und dem Koppelkondensator C7 verbunden ist. Der Kondensator C6 dient außerdem als Resonanzkondensator, wenn der Heizstrom durch den Kaltleiter KL nach erfolgtem Vorheizen der Elektroden reduziert wurde.The circuit arrangement also has an active harmonic filter. The filter consists of two diodes D5, D6 connected in series and in the forward DC direction to the positive pole of the power rectifier GL, the center tap M2 between the two diodes D5, D6 being connected via a capacitor C4 to the center tap M1 between the two transistors T1, T2. In addition to the first two diodes D5, D6, the harmonic filter also contains two further diodes D7, D8 connected in series and in the forward DC direction, the center tap M3 between these two diodes D7, D8 via a capacitor C5 also with the center tap M1 between the two transistors T1, T2 and a capacitor C6 to the tap M4 between the resonance inductor L1 and the coupling capacitor C7. The capacitor C6 also serves as a resonance capacitor if the heating current through the PTC thermistor KL has been reduced after the electrodes have been preheated.

Die Kondensatoren des Oberwellenfilters pumpen laufend Energie in den Glättungskondensator C2, so daß eine sinusförmige Netzstromaufnahme gewährleistet ist. Genauere Angaben über die Funktionsweise des Ober­wellenfilters sind der DE-OS 36 23 749 zu entnehmen.The capacitors of the harmonic filter continuously pump energy into the smoothing capacitor C2, so that a sinusoidal mains current consumption is guaranteed. More detailed information on the mode of operation of the harmonic filter can be found in DE-OS 36 23 749.

Durch das dauernde Rückpumpen von Energie kann es bei Ausfall der Niederdruckentladungslampe (Luftzieher etc.) zu einer Überladung und damit einer Zerstörung des Glättungskondensators C2 kommen. Die Schaltungs­anordnung weist daher zusätzlich eine Abschaltvorrich­tung mit Triggersteuerung auf. Diese besteht aus einer Reihenschaltung einer Diode D2, eines Widerstandes R2 und eines Thyristors TH, die die Basis des Transistors T1 mit dem Minuspol des Netzgleichrichters GL ver­bindet. Außerdem ist der Mittenabgriff M5 zwischen dem Widerstand R2 und dem Thyristor TH über einen Wider­stand R1 mit dem Pluspol des Glättungskondensators C2 verbunden. Die Triggersteuerung besteht aus den beiden Zenerdioden DZ1, DZ2, die das Gate des Thyristors TH mit dem Pluspol des Glättungskondensators C2 ver­binden, sowie aus dem Widerstand R3, der das Gate des Thyristors TH mit dessen Kathode verbindet.Due to the constant pumping back of energy, the low-pressure discharge lamp (air extractor, etc.) may overcharge and thus destroy the smoothing capacitor C2. The circuit arrangement therefore additionally has a switch-off device with trigger control. This consists of a series connection of a diode D2, a resistor R2 and a thyristor TH, which connects the base of the transistor T1 to the negative pole of the mains rectifier GL. In addition, the center tap M5 is connected between the resistor R2 and the thyristor TH via a resistor R1 to the positive pole of the smoothing capacitor C2. The trigger control consists of the two Zener diodes DZ1, DZ2, which connect the gate of the thyristor TH to the positive pole of the smoothing capacitor C2, and of the resistor R3, which connects the gate of the thyristor TH to its cathode.

Im Fall, daß die Spannung am Glättungskondensator C2 einen gewissen Höchstwert überschreitet, werden die beiden Zenerdioden DZ1 und DZ2 mit derselben Gesamt­durchbruchspannung leitend und triggern so den Abschaltthyristor TH. Damit wird der Basis des Tran­sistors T1 die Steuerenergie durch Ableitung zum negativen Pol des Netzgleichrichters GL entzogen; der Transistor wird gesperrt und der Resonanzkreis aus Induktivität L1, Kondensator C7 und Kondensator C8 entregt. Durch die Verbindung des Thyristors TH über den Widerstand R1 mit dem Pluspol des Netzgleichrich­ters GL wird der Thyristor TH im leitenden Zustand ge­halten, so daß jeder erneute Schwingungseinsatz unter­bunden ist. Die Diode D2 sperrt die Wechselspannung vom Anodenkreis des Thyristors TH.In the event that the voltage across the smoothing capacitor C2 exceeds a certain maximum value, the two Zener diodes DZ1 and DZ2 become conductive with the same total breakdown voltage and thus trigger the turn-off thyristor TH. The control energy is thus withdrawn from the base of the transistor T1 by dissipation to the negative pole of the mains rectifier GL; the transistor is blocked and the resonance circuit of inductance L1, capacitor C7 and capacitor C8 is de-energized. By connecting the thyristor TH over the resistor R1 with the positive pole of the mains rectifier GL, the thyristor TH is kept in the conductive state, so that any renewed use of vibrations is prevented. The diode D2 blocks the AC voltage from the anode circuit of the thyristor TH.

Die Elektrode E2 ist zwischen der Diode D6 bzw. D8 des Oberwellenfilters und dem positiven Eingang des Tran­sistors T1 des Gegentaktgenerators angeordnet. Durch diese erfindungsgemäße Eingliederung der Elektrode E2 zwischen Netzgleichrichter und Gegentaktfrequenz­generator wird beim Auswechseln der Lampe die Ver­bindung zwischen dem Netzgleichrichter und dem Gegen­taktfrequenzgenerator unterbrochen. Damit wird sowohl der Gegentaktfrequenzgenerator abgeschaltet als auch der Thyristor TH in den Sperrzustand übergeführt. Der Abschaltkreis ist somit bei fehlender Lampe nicht aktiv, wodurch keine Verlustleistung im Haltestrom­kreis verbraucht wird. Nach Einsatz einer neuen Lampe LP kann der Generator sofort wieder anlaufen, da die Thyristor-Abschaltvorrichtung durch die Herausnahme der defekten Lampe außer Funktion gesetzt wurde.The electrode E2 is arranged between the diode D6 and D8 of the harmonic filter and the positive input of the transistor T1 of the push-pull generator. By integrating the electrode E2 between the mains rectifier and push-pull frequency generator according to the invention, the connection between the mains rectifier and the push-pull frequency generator is interrupted when the lamp is replaced. Thus, the push-pull frequency generator is switched off and the thyristor TH is brought into the blocking state. The switch-off circuit is therefore not active when the lamp is missing, so that no power loss is consumed in the holding circuit. After using a new lamp LP, the generator can start up again immediately because the thyristor shutdown device has been deactivated by removing the defective lamp.

Die beiden Stromanschlüsse der Elektrode E2 sind außerdem noch durch eine Diode D9 in Gleichstromsper­richtung überbrückt. Durch den Aufbau der Schaltungs­anordnung werden die Elektroden vorgeheizt. Diese Vorheizung ist jedoch ungleichmäßig, da durch die Eingliederung der Elektrode E2 zwischen Netz- und Generatorteil diese Elektrode aufgrund des Gleich­stromdurchflusses eine zusätzliche Vorheizung erfährt. Mit Hilfe der Diode wird der Vorheizstrom des Vorheiz­kreises an dieser Wendel auf den halben Wert herab­gesetzt, so daß beide Elektroden etwa gleich stark belastet werden.The two current connections of the electrode E2 are also bridged by a diode D9 in the direct current blocking direction. The electrodes are preheated by the construction of the circuit arrangement. However, this preheating is uneven, since the electrode E2 is inserted between the power supply and generator part, and this electrode is preheated due to the direct current flow. With the help of the diode, the preheating current of the preheating circuit on this coil is reduced to half the value, so that both electrodes are subjected to approximately the same load.

In der nachfolgenden Liste sind die verwendeten Schal­tungselemente für eine Schaltungsanordnung mit Ab­schalt- und Wiedereinschaltvorrichtung zum Betrieb einer 36 W-Niederdruckentladungslampe wiedergegeben: FD : 2 x 60 mH C1 : 0,22 µF GL : B 250 C800 GP C2 : 10 µF/450 V R1 : 68 kΩ/2W R2 : 120Ω/1 W DZ1, DZ2 : ZGP 10-250 R3 : 1 kΩ/0,3 W TH : TAG XO 103 MA R4, R9 : 470 kΩ/0,6 W C3 : 100 nF/100 V DC : N 413 M D1, D2, D9 : 1 N 4007 GP R5, R6 : 8,2Ω T1, T2 : BUT 54 R7, R8 : 0,56Ω RK, 1.1, RK 1.2, RK 1.3 : RK 13 x 7 x 5 n 1.1 = 7 Windungen n 1.2 = n 1.3 = 1 Windung D3 bis D8 : RGP 10 J C4 : 4,7 nF C5, C6 : 10 nF C7 : 150 nF C8 : 15 nF L1 : EF 25, 1 mH KL : PTC 875 The following list shows the circuit elements used for a circuit arrangement with a switch-off and switch-on device for operating a 36 W low-pressure discharge lamp: FD : 2 x 60 mH C1 : 0.22 µF GL : B 250 C800 GP C2 : 10 µF / 450 V R1 : 68 kΩ / 2W R2 : 120Ω / 1 W DZ1, DZ2 : ZGP 10-250 R3 : 1 kΩ / 0.3 W TH : DAY XO 103 MA R4, R9 : 470 kΩ / 0.6 W C3 : 100 nF / 100 V DC : N 413 M D1, D2, D9 : 1 N 4007 GP R5, R6 : 8.2Ω T1, T2 : BUT 54 R7, R8 : 0.56Ω RK, 1.1, RK 1.2, RK 1.3 : RK 13 x 7 x 5 n 1.1 = 7 turns n 1.2 = n 1.3 = 1 turn D3 to D8 : RGP 10 y C4 : 4.7 nF C5, C6 : 10 nF C7 : 150 nF C8 : 15 nF L1 : EF 25, 1 mH KL : PTC 875

Claims (2)

1. Schaltungsanordnung zum hochfrequenten Betrieb einer Niederdruckentladungslampe (LP), wobei die Schaltung folgende Merkmale aufweist:
- einen Netzgleichrichter (2, GL)
- einen mit dem Gleichstromausgang des Netzgleich­richters (2, GL) verbundenen selbsterregten Gegen­taktfrequenzgenerator (3) mit zwei alternierend schaltenden Transistoren (T1, T2), wobei ein Mittenabgriff (M1) zwischen den beiden Transistoren (T1, T2) vorgesehen ist, einer Ansteuerschaltung und einem Serienresonanzkreis, bestehend aus Resonanz­induktivität (L1), Kopplungskondensator (C7) und Resonanzkapazität (C8, C6) in Kombination mit
- einer Abschaltvorrichtung, bestehend aus einer Reihenschaltung einer Diode (D2) eines Widerstands (R2) und eines Thyristors (TH) mit Triggerschaltung, die die Basis des mit dem Pluspol des Netzgleich­richters (2, GL) verbundenen Transistors (T1) mit dem Minuspol des Netzgleichrichters (2, GL) verbindet sowie einem Widerstand (R1), der den Pluspol des Netzgleichrichters (2, GL) mit einem Abgriff (M5) zwischen der Diode (D2) und dem Thyristor (TH) verbindet
- Anschlußleitungen für die Niederdruckentladungs­ lampe (LP), wobei eine Leitung die erste Elektrode (E1) der Lampe (LP) über die Resonanzinduktivität (L1) mit dem Mittenabgriff (M1) zwischen den beiden Transistoren (T1, T2) und eine weitere Leitung die zweite Elektrode (E2) der Lampe (LP) mit dem Plus- oder Minuspol des Netzgleichrichters (2, GL) verbindet
- einen Glättungskondensator (C2) parallel zu den Schaltstrecken der beiden Transistoren (T1, T2) des Gegentaktfrequenzgenerators (3)
dadurch gekennzeichnet, daß die zweite Elektrode (E2) die elektrische Verbindung zwischen dem Netzgleich­richter (2, GL) und dem Gegentaktfrequenzgenerator (3) der Schaltungsanordnung bildet.
1. Circuit arrangement for high-frequency operation of a low-pressure discharge lamp (LP), the circuit having the following features:
- a line rectifier (2, GL)
- A self-excited push-pull frequency generator (3) connected to the direct current output of the mains rectifier (2, GL) with two alternating switching transistors (T1, T2), a center tap (M1) being provided between the two transistors (T1, T2), a control circuit and a series resonance circuit consisting of resonance inductance (L1), coupling capacitor (C7) and resonance capacitance (C8, C6) in combination with
- A shutdown device, consisting of a series connection of a diode (D2), a resistor (R2) and a thyristor (TH) with a trigger circuit, which connects the base of the transistor (T1) connected to the positive pole of the mains rectifier (2, GL) with the negative pole of the Mains rectifier (2, GL) connects and a resistor (R1), which connects the positive pole of the mains rectifier (2, GL) with a tap (M5) between the diode (D2) and the thyristor (TH)
- Connection lines for the low pressure discharge lamp (LP), one line connecting the first electrode (E1) of the lamp (LP) via the resonance inductance (L1) with the center tap (M1) between the two transistors (T1, T2) and a further line connecting the second electrode (E2) the lamp (LP) connects to the positive or negative pole of the mains rectifier (2, GL)
- A smoothing capacitor (C2) parallel to the switching paths of the two transistors (T1, T2) of the push-pull frequency generator (3)
characterized in that the second electrode (E2) forms the electrical connection between the mains rectifier (2, GL) and the push-pull frequency generator (3) of the circuit arrangement.
2. Schaltungsanordnung nach Anspruch 1, dadurch ge­kennzeichnet, daß die beiden Anschlüsse der zweiten Elektrode (E2) durch eine in Gleichstromsperrichtung geschaltete Diode (D9) überbrückt sind.2. Circuit arrangement according to claim 1, characterized in that the two connections of the second electrode (E2) are bridged by a diode (D9) connected in the DC blocking direction.
EP19890102899 1988-02-22 1989-02-20 Drive circuitry for a low-pressure discharge lamp Withdrawn EP0330118A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3805510A DE3805510A1 (en) 1988-02-22 1988-02-22 CIRCUIT ARRANGEMENT FOR OPERATING A LOW-PRESSURE DISCHARGE LAMP
DE3805510 1988-02-22

Publications (2)

Publication Number Publication Date
EP0330118A2 true EP0330118A2 (en) 1989-08-30
EP0330118A3 EP0330118A3 (en) 1991-02-27

Family

ID=6347917

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19890102899 Withdrawn EP0330118A3 (en) 1988-02-22 1989-02-20 Drive circuitry for a low-pressure discharge lamp

Country Status (4)

Country Link
US (1) US4949013A (en)
EP (1) EP0330118A3 (en)
DE (1) DE3805510A1 (en)
FI (1) FI885273A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2700434A1 (en) * 1993-01-12 1994-07-13 De Mere Henri Edouard Courier Fluorescent lamp ballast embodying transistor-based frequency-changer
FR2738444A1 (en) * 1995-09-06 1997-03-07 Lor Hak Self-oscillating electronic ballast with single transformer for fluorescent lamps
EP0707437A3 (en) * 1994-10-12 1997-12-03 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit for operating one or more low pressure discharge lamps
WO1999034649A1 (en) * 1997-12-23 1999-07-08 Tridonic Bauelemente Gmbh Method for detecting a lamp change and electronic lamp ballast for operating gas-discharge lamps using such a method for detecting a lamp change
EP1356713A2 (en) * 2001-02-02 2003-10-29 Mass Technology (H.K.) Ltd. A modified electronic ballast for a fluorescent lamp

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5051661A (en) * 1989-01-09 1991-09-24 Lee Sang Woo Protective circuit for fluorescent lamp stabilizer
IL93265A0 (en) * 1990-02-04 1990-11-29 Gaash Lighting Ind Electronic ballast for gas discharge lamp
DE4010435A1 (en) * 1990-03-31 1991-10-02 Trilux Lenze Gmbh & Co Kg Mains connection device for fluorescent lamp - has inverse regulator for prodn. of constant operating voltage, and electronic switch in series branch to load in series with diode
DE4121009C2 (en) * 1991-06-21 1994-01-13 Prolux Maschinenbau Gmbh Circuit arrangement for operating a discharge lamp
DE4120649A1 (en) * 1991-06-22 1992-12-24 Vossloh Schwabe Gmbh OVERVOLTAGE PROTECTED BALLAST
DE4140557A1 (en) * 1991-12-09 1993-06-17 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh CIRCUIT ARRANGEMENT FOR OPERATING ONE OR MORE LOW-PRESSURE DISCHARGE LAMPS
US5424613A (en) * 1993-12-22 1995-06-13 At&T Corp. Method of operating a gas-discharge lamp and protecting same from overload
US5424611A (en) * 1993-12-22 1995-06-13 At&T Corp. Method for pre-heating a gas-discharge lamp
DE4410492A1 (en) * 1994-03-25 1995-09-28 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Circuit arrangement for operating low-pressure discharge lamps
TW296894U (en) * 1995-11-21 1997-01-21 Philips Electronics Nv Circuit arrangement
GB9622768D0 (en) * 1996-11-01 1997-01-08 Lab Craft Limited Fluorescent lamp failure warning device
US6034485A (en) * 1997-11-05 2000-03-07 Parra; Jorge M. Low-voltage non-thermionic ballast-free energy-efficient light-producing gas discharge system and method
US5998941A (en) * 1997-08-21 1999-12-07 Parra; Jorge M. Low-voltage high-efficiency fluorescent signage, particularly exit sign
US6300722B1 (en) 1997-11-05 2001-10-09 Jorge M. Parra Non-thermionic ballast-free energy-efficient light-producing gas discharge system and method
DE19821351A1 (en) * 1998-05-13 1999-11-18 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Circuit arrangement for operating electric lamps
US6465971B1 (en) 1999-06-02 2002-10-15 Jorge M. Parra Plastic “trofer” and fluorescent lighting system
US6411041B1 (en) 1999-06-02 2002-06-25 Jorge M. Parra Non-thermionic fluorescent lamps and lighting systems
DE10046443A1 (en) * 2000-09-18 2002-03-28 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Electronic circuit for the detection of the change in gas discharge lamps
TW319487U (en) 2000-09-27 1997-11-01 Patent Treuhand Ges Fuer Elek Sche Gluhlampen Mbh Co Ltd Operating device for electrical lamps
US6731075B2 (en) * 2001-11-02 2004-05-04 Ampr Llc Method and apparatus for lighting a discharge lamp
US6936973B2 (en) * 2002-05-31 2005-08-30 Jorge M. Parra, Sr. Self-oscillating constant-current gas discharge device lamp driver and method
US6750619B2 (en) 2002-10-04 2004-06-15 Bruce Industries, Inc. Electronic ballast with filament detection
US6819063B2 (en) * 2002-12-13 2004-11-16 Bruce Industries, Inc. Sensing voltage for fluorescent lamp protection
DE102004001617A1 (en) * 2004-01-09 2005-08-11 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating light sources
DE102004001618A1 (en) * 2004-01-09 2005-08-11 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating light sources
DE102004045514A1 (en) * 2004-09-20 2006-03-30 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating at least one light source
DE102006052024A1 (en) * 2006-11-03 2008-05-08 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for low-pressure discharge lamps
CN103491694B (en) * 2013-08-27 2016-03-09 钟海停 Module special for fluorescent lamp energy conservation

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1982000561A1 (en) * 1980-08-05 1982-02-18 Kerscher M Installation for starting a discharge lamp with heated electrodes
EP0056889A1 (en) * 1981-01-26 1982-08-04 Top-Ping Hwang Simplified power source for fluorescent lamps
EP0198632A2 (en) * 1985-04-04 1986-10-22 Chwee Tor Lee Electronic ballast for fluorescent lamps
EP0239793A1 (en) * 1986-03-14 1987-10-07 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating low-pressure discharge lamps
EP0276460A1 (en) * 1987-01-08 1988-08-03 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating a low-pressure discharge lamp

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1982000561A1 (en) * 1980-08-05 1982-02-18 Kerscher M Installation for starting a discharge lamp with heated electrodes
EP0056889A1 (en) * 1981-01-26 1982-08-04 Top-Ping Hwang Simplified power source for fluorescent lamps
EP0198632A2 (en) * 1985-04-04 1986-10-22 Chwee Tor Lee Electronic ballast for fluorescent lamps
EP0239793A1 (en) * 1986-03-14 1987-10-07 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating low-pressure discharge lamps
EP0276460A1 (en) * 1987-01-08 1988-08-03 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit arrangement for operating a low-pressure discharge lamp

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2700434A1 (en) * 1993-01-12 1994-07-13 De Mere Henri Edouard Courier Fluorescent lamp ballast embodying transistor-based frequency-changer
EP0707437A3 (en) * 1994-10-12 1997-12-03 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH Circuit for operating one or more low pressure discharge lamps
FR2738444A1 (en) * 1995-09-06 1997-03-07 Lor Hak Self-oscillating electronic ballast with single transformer for fluorescent lamps
WO1999034649A1 (en) * 1997-12-23 1999-07-08 Tridonic Bauelemente Gmbh Method for detecting a lamp change and electronic lamp ballast for operating gas-discharge lamps using such a method for detecting a lamp change
EP1356713A2 (en) * 2001-02-02 2003-10-29 Mass Technology (H.K.) Ltd. A modified electronic ballast for a fluorescent lamp

Also Published As

Publication number Publication date
FI885273A0 (en) 1988-11-15
DE3805510A1 (en) 1989-08-31
US4949013A (en) 1990-08-14
EP0330118A3 (en) 1991-02-27
FI885273A (en) 1989-08-23

Similar Documents

Publication Publication Date Title
EP0330118A2 (en) Drive circuitry for a low-pressure discharge lamp
EP0239793B1 (en) Circuit arrangement for operating low-pressure discharge lamps
EP0253224B1 (en) Circuit arrangement for operating low-pressure discharge lamps
EP0679046A1 (en) Circuit for operating low-pressure discharge lamps
DE10259585A1 (en) Electronic adapter system with emergency lighting properties has inverter adapter circuit with tuning frequency stage for feeding oscillatory current to supply lamp without pre-heating
EP0356818B1 (en) Circuitry for driving a load
EP0372303B1 (en) Circuit arrangement for operating a low-pressure discharge lamp
CH657003A5 (en) CONTROL UNIT FOR OPERATING AT LEAST ONE LOW PRESSURE DISCHARGE LAMP.
DE4140557A1 (en) CIRCUIT ARRANGEMENT FOR OPERATING ONE OR MORE LOW-PRESSURE DISCHARGE LAMPS
EP0062276B1 (en) Ballast circuit for the operation of low-pressure discharge lamps
EP0699016A2 (en) Circuit for operating low pressure discharge lamps
EP0439240B1 (en) Electronic ballast
EP0753987B1 (en) Circuit and method of operation for electric lamps
EP0917412B1 (en) Self-oscillating circuit with simplified startup circuit
EP0541909B1 (en) Discharge lamp driving circuit
EP0691800A2 (en) Circuit for operating low pressure discharge lamps
EP0276460B1 (en) Circuit arrangement for operating a low-pressure discharge lamp
EP1028606B1 (en) Circuit for operating at least one low-pressure discharge lamp
EP0871347B1 (en) Ballast with automatic restart
EP0050131B1 (en) Ballast for a discharge lamp
EP0697803A2 (en) Circuit for operating discharge lamps
EP0949851B1 (en) Ballast for low-pressure discharge lamp
EP0648068A1 (en) Circuit for operating electrical lamps
DE3835121C2 (en) Circuit arrangement for operating a low-pressure discharge lamp
DE3112281A1 (en) Ballast for connection of a discharge lamp

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): CH DE FR GB IT LI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

17P Request for examination filed

Effective date: 19901220

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): CH DE FR GB IT LI

17Q First examination report despatched

Effective date: 19930422

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 19930907