EP0249485B1 - Zündschaltung für eine Leuchtstofflampe - Google Patents

Zündschaltung für eine Leuchtstofflampe Download PDF

Info

Publication number
EP0249485B1
EP0249485B1 EP19870305208 EP87305208A EP0249485B1 EP 0249485 B1 EP0249485 B1 EP 0249485B1 EP 19870305208 EP19870305208 EP 19870305208 EP 87305208 A EP87305208 A EP 87305208A EP 0249485 B1 EP0249485 B1 EP 0249485B1
Authority
EP
European Patent Office
Prior art keywords
lamp
voltage
circuit
switch
circuit according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19870305208
Other languages
English (en)
French (fr)
Other versions
EP0249485A1 (de
Inventor
Michael John Maytum
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.)
Texas Instruments Ltd
Texas Instruments Inc
Original Assignee
Texas Instruments Ltd
Texas Instruments Inc
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 Texas Instruments Ltd, Texas Instruments Inc filed Critical Texas Instruments Ltd
Publication of EP0249485A1 publication Critical patent/EP0249485A1/de
Application granted granted Critical
Publication of EP0249485B1 publication Critical patent/EP0249485B1/de
Expired legal-status Critical Current

Links

Images

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
    • H05B41/02—Details
    • H05B41/04—Starting switches
    • H05B41/042—Starting switches using semiconductor devices
    • H05B41/044—Starting switches using semiconductor devices for lamp provided with pre-heating electrodes
    • H05B41/046—Starting switches using semiconductor devices for lamp provided with pre-heating electrodes using controlled semiconductor devices

Definitions

  • This invention relates to a starter circuit for a fluorescent tube lamp and a lamp fitting incorporating the circuit.
  • Fluorescent tubes are lamps which produce light by means of an electrical discharge in a gas which excites a phosphor coating on the tube.
  • the impedance of the tube When in operation, the impedance of the tube is negative and therefore requires an added series impedance so that the operation is stable.
  • the series impedance is chosen to be inductive so as to reduce power losses and to produce the pulses for striking the tube.
  • the "running" voltage is between 20 and 60 per cent of the nominal AC supply voltage, the remainder of that voltage being dropped across the added series impedance.
  • the purpose of a starting circuit is to strike the discharge in the tube and the voltage required to achieve this is higher than the running voltage and depends on the age of the tube, its operational environment and the length of time for which striking voltage is applied. Tubes have heated cathodes which provide a source of ions and electrons for the discharge and reduce the magnitude of the voltage required to strike the tube. It is possible to strike a tube when the cathodes are cold but the striking voltage/time requirement is usually beyond the capability of conventional starting circuits; and, in any case, the cold striking of a tube with high voltage pulses tends to shorten its life.
  • a well-known circuit for achieving this includes a glow tube switch which is used to complete a series circuit including the ballast series impedance and the two cathode heaters, the switch itself being connected between the two cathode heaters.
  • this strip When sufficiently hot, this strip closes some switch contacts which short-circuit the glow tube and cause the cathode heaters to be heated by the supply current. After a certain period of time the bimetallic strip cools allowing the switch to open again which interrupts the heater current and causes the ballast impedance, which is usually an inductor, to produce an e.m.f. in addition to the supply voltage which is usually sufficient to strike the tube. If the tube does not strike, the glow tube will repeat its attempt to strike it as described above. After the tube has struck insufficient voltage is applied to the glow tube for the discharge to be set up in it and the starter remains quiescent.
  • the main problems with the glow tube switch as described above are that the actual time of opening of the switch is random relative to the supply voltage so that the actual e.m.f. applied to the tube in an attempt to strike it is frequently insufficient so that the striking of the tube is delayed and it is preceded by an unpleasant series of flashes at intervals of about 1 second. Furthermore, the performances of the glow tube starters are very variable which can result in unreliable operation in some instances. In addition, the life expectancy of the glow tube switch is unpredictable. Moreover, the continued attempts to strike a faulty tube by such a switch can be very annoying.
  • a starter circuit for an AC energised fluorescent tube lamp having cathodes with heaters and an inductive ballast impedance connected in series with the lamp across an AC supply, and in which in use the starter circuit is connected between the cathodes of the lamp itself, wherein the starter circuit includes a switch and a control circuit for the switch which is responsive to the presence of voltage across the tube to cause the switch to execute a cycle of connecting together the cathodes of the tube through a low resistance path and then breaking the connection between them several times in each half cycle of the AC supply, whereby the starter circuit when in use causes the ballast impedance to apply a corresponding succession of voltage pulses to the lamp.
  • the circuit may include a full wave rectifier producing a DC supply for the other parts of the circuit from the alternating voltage across the lamp.
  • the switch may include a thyristor constructed to require a high holding current to maintain conduction or otherwise being capable of being turned off by a signal applied to its gate and preferably also has a zener diode connected so as to limit the voltage of the pulses produced by the ballast impedance when the circuit is in use.
  • the control circuit may be responsive to the current through the low resistance path to cause the switch to break the connection whenever the current reaches a particular value.
  • the control circuit may include an oscillator producing a rectangular wave for controlling the switch and having a frequency and a mark to space ratio matched to the charge and discharge characteristics of an inductive ballast impedance with which the starter circuit is intended to be used.
  • the control circuit may include a circuit for delaying the start of the switching cycles for a period of time after switching on the supply to the lamp, and therefore to the starter circuit, to permit the cathodes of the lamp to be preheated before the pulses are applied to the lamp.
  • the control circuit may be responsive to a characteristic of the voltage across the lamp to detect when it strikes and then terminate the switching cycles for at least the remainder of the particular half cycle of the supply.
  • a timing circuit may be provided to terminate the switching cycles if the lamp does not strike within a predetermined time of being switched on.
  • FIGURE 1 is a block diagram of the complete energisation circuit for a fluorescent tube lamp incorporating a starter circuit according to the present invention
  • FIGURES 2A to 2D represent waveforms occurring in parts of the circuits shown in Figure 1 which will be used to explain the operation of the circuit
  • FIGURE 3 is a detailed circuit diagram of a starter circuit according to the invention.
  • the present invention relates to a starter circuit for a fluorescent tube lamp and to a lamp incorporating such a circuit.
  • the operation of the circuit could be described without reference to the other components used in the energisation circuit for the lamp, the point of the various functions of the starter circuit would only become apparent from a consideration of their effects in the overall energisation circuit with a lamp and therefore for convenience the entire energisation circuit and its manner of operation will be described.
  • an agruating mains electricity supply is connected to terminals 1 and 2, the supply typically having a voltage of 240 volts.
  • the terminal 1 is connected via an on/off switch 3 and a ballast inductance 4 to a cathode 5 of a fluorescent tube lamp 6.
  • the lamp 6 has a second cathode 7 which is connected directly to the terminal 2.
  • the cathodes 5 and 7 incorporate heaters and these take the form of electrical resistances through which current is caused to flow from the supply terminals 1 and 2 to the starter circuit 8 connected between the ends of the cathodes 5 and 7 remote from the terminals 1 and 2.
  • a capacitor 9 is connected at nodes A and B in parallel with the starter circuit 8 for the purpose of suppressing radio frequency interference due to the action of the starter circuit in conjunction with the inductance 4.
  • the starter circuit 8 includes a full wave bridge rectifier 10 producing a DC supply across conductors 11 and 12.
  • the conductors 11 and 12 are joined by a zener diode 13 and a controllable switch 14.
  • a control circuit 15 also receives the DC supply and produces on a conductor 16 control signals for the switch 14.
  • the switch 14 is shown as a mechanical switch, it would in practice either be a thyristor able to be turned off by a signal applied to its gate or a device known as a fluoractor as described in European Patent Application No. 0118309. In the case where switch 14 is a fluoractor, the zener diode 13 is incorporated into it.
  • the control circuit 15 may include means connected in series with the switch 14 for responding to the current through it.
  • control circuit 15 is arranged to open and close the switch 14 at about 300 to 400 times per second so that in each half cycle of the AC supply, assumed to be of 50 Hz, there are three to four pulses applied to the lamp 6 when the switch 14 is open-circuited and the energy stored in the inductance 4 is discharged to produce the pulses.
  • the zener diode 13 operates to limit the voltage of the pulses produced by the inductance 4 and in doing so extends their duration, it having been found that a pulse of slightly lower voltage but of longer duration is more effective to cause a fluorescent tube lamp to strike.
  • the circuit has the advantage that on switching on the lamp produces a progressively increasing amount of light without apparent flashing until the lamp strikes. If a preheating time is provided, for example by being built into the control circuit 15, then the progressive brightening of the lamp will follow after, say, half a second delay normally provided for the preheating of the cathodes.
  • Figure 2A represents the AC supply and Figure 2B is the supply after full wave rectification by the rectifier 10.
  • Figure 2C represents the current pulses in the inductance 4 in each half cycle of the mains supply, the half cycles being marked by the lines 17.
  • Figure 2D represents the voltage across the lamp 6. As shown in Figures 2C and 2D, in the first half cycle the switch 14 is opened three times and three pulses of voltage V determined by the zener diode 13 are applied to the lamp 6. It is assumed that the lamp does not strike during this half cycle, but the gas in the lamp will be heated and the lamp caused to produce a small amount of light output which will not, however, appear as flashing because the frequency of the pulsing is too high.
  • the lamp is assumed to strike on the second pulse which therefore appears shortened in Figure 2D, so that the voltage across the tube falls to V1 as determined by the conduction of the lamp.
  • the lamp produces a greater amount of light because it is struck for about half the time.
  • the lamp is assumed to strike on the first pulse and produces even more light by having been struck for about three-quarters of the half cycle.
  • control circuit 15 is arranged not only to detect the striking of the lamp and to terminate the pulses in the rest of the half cycle in which the striking occurred but also to discontinue the application of pulses to the switch 14 after detecting the striking of the lamp on the first pulse in preceding half cycles or after a predetermined period of time.
  • the striking of the lamp can be detected in several ways, for example by measuring the duration of the voltage pulse across the lamp and noting when it is greatly reduced as a result of the striking of the lamp, measuring the voltage across the lamp and noting the rapid reduction in that voltage as a result of the lamp striking, or monitoring the current through the zener diode 13 and noting when it is interrupted.
  • the ends of half cycles of the AC supply could be detected by a zero voltage condition between the conductors 11 and 12.
  • the generation of the pulses used to open-circuit the switch 14 may be achieved by monitoring the current through the switch which will be dependent on the current through the inductance 4 and when the current through the switch reaches a predetermined value corresponding to a required energy charge in the inductance 4, the switch 14 is open-circuited. This will result in the pulses applied to the lamp 6 being of substantially the same energy which can therefore be adjusted to provide optimum starting conditions for the lamp without causing damage to its cathodes. If preheating of the cathode is not employed, it is desirable to restrict the energy of the starting pulses so as to warm up the gas in the lamp without disrupting the material from the cathodes.
  • FIG 3 shows in detail the circuit diagram of the starter circuit 8 of Figure 1.
  • the nodes A and B of the circuit of Figure 1 are marked in Figure 3 connected to the rectifier bridge 10 which produces a DC voltage across conductors 11 and 12.
  • the switch 14 and the zener diode 13 are combined in a fluoractor 20 connected from the conductor 11 through a series of four diodes D5, D6, D7 and D8 to the conductor 12.
  • the junction of the fluoractor 20 and the diode 5 is connected through a diode D9 to a conductor 21 on which a steady voltage is maintained relative to the conductor 12 smoothed by a capacitor C1.
  • the voltage on the conductor 11 is not smoothed and retains the form shown in Figure 2B.
  • a comparator IC1A compares the voltage across a resistor R1 shunting the diode D8 with the steady voltage established at the junction of resistors R3 and R4 connected in series between conductor 21 and conductor 12, and the output of the comparator IC1A is applied to the set input of a D-type flip-flop IC2 which causes the Q-output of IC2 to go high when the voltage across the resistor R1 due to the current flowing through fluoractor 20 and down the diode chain reaches a predetermined value. This causes the transistor TR1 to become conducting which switches off the fluoractor causing a pulse to be applied to the lamp.
  • a comparator IC1C which compares a proportion of the voltage between conductors 11 and 12 determined by resistors R15 and R16 in series with a voltage at the junction of resistors R12 and R13 of the series chain R12, R13 and R14 connected from conductor 21 and conductor 12.
  • the output of the comparator IC1C clocks the flip-flop IC2 which, as its D-input is low for reasons to be explained, causes its Q-output of IC2 to become low again switching off TR1 and allowing the fluoractor 20 to turn on again for another cycle as just described.
  • the voltage pulse across it will be shortened and there will be a rapid decrease in the voltage of the pulse.
  • This rapid decrease is detected by the transistor TR2 in conjunction with the differentiating circuit formed by capacitor C3 and resistor R11. This causes the collector of the transistor TR2 to go low which in turn via the comparator IC1B causes the D-input of the flip-flop IC2 to go high.
  • This rapid decrease occurs before the pulse decays below 400 volts as mentioned above so that under these circumstances the D-input is high before the flip-flop IC2 is clocked by comparator IC1C.
  • the Q-output of the flip-flop IC2 remains high and the transistor TR1 is kept conducting so that the fluoractor 20 is maintained in the nonconducting condition and the lamp can continue its conduction, at least until the next half cycle. If the lamp does not strike the D-input of IC2 will remain low as mentioned above.
  • a comparator IC1D detects when the voltage on the conductor 11 falls below 30 volts positive with respect to conductor 12 and through the NAND-gate IC3 resets the flip-flop IC2, so that its Q-output becomes low again and the transistor TR1 is turned off so that the fluoractor 20 can be triggered into conduction at the beginning of the next half cycle.
  • the NAND-gate IC3 serves to eliminate simultaneous application of a low condition to both the R and S inputs of the flip-flop IC2 because of the control of the NAND-gate IC3 by the Q-output of the flip-flop.
  • the circuit turns off the fluoractor 20 repeatedly in each half cycle until the lamp strikes when the fluoractor 20 is held in the off condition up to the end of the half cycle.
  • a timing circuit formed by resistor R19 and capacitor C5 produces a rising voltage which is applied to a comparator IC4A the output of which is connected through diode D11 to the set input of the flip-flop IC2 to prevent it being reset again until the mains supply is turned off and then on again.
  • a preheating delay can be provided in the circuit by connecting a capacitor C2 in parallel with resistor R3 which thereby causes the voltage applied to the non-inverting input of the comparator IC1A to start substantially at the potential of the conductor 21 and to fall gradually to the normal operating value as the capacitor C2 is charged up by current through resistor R4. This means that the output of the comparator IC1A is prevented from going low in response to the voltage developed across the resistor R1 for a short period of time. This permits the cathodes of the lamp to heat up before fluoractor 20 is turned off for the first time and pulses start to be applied to the lamp.
  • circuit of Figure 3 includes certain of the alternatives mentioned above in the description of the control circuit 15.
  • the circuit of Figure 3 could be modified in a number of ways. For example, a capacitor could be connected across the resistor R4 instead of resistor R3 with the result that the width of the pulses applied to the lamp would start at a low value and increase gradually to the normal value because the comparator IC1A would be caused to trigger the flip-flop IC2 at lower levels of current through the fluoractor 20 than normal.
  • This latter feature could be combined with a preheating delay by the use of an additional comparator to block the start of the gradually increasing pulses until after the preheating delay, which would be useful for any lamps which are susceptible to "end blackening" when pulsed before the cathodes are sufficiently heated.
  • a fixed frequency oscillator could be provided having a frequency and mark to space ratio so chosen with reference to the inductance 4 to provide the most appropriate pulse energies for different lamps.
  • Small fluorescent lamps require higher values of inductance, and if the triggering of the pulses is based on the current through the inductance as described above, then the smaller tubes would receive larger energy pulses which they do not require. With the time of the charging current applied to the inductance being fixed, the higher values of inductance will have a smaller current through them because of the lower rate of increase of current and thus smaller tubes would receive more appropriately sized striking pulses.
  • the analogue timing circuits used in Figure 3 could be replaced by a pulse generator and counters which would permit much of the circuit to be realised by a custom-built gate array which would avoid the need to design an integrated circuit specifically for it.

Landscapes

  • Circuit Arrangements For Discharge Lamps (AREA)

Claims (17)

  1. Zündschaltung für eine wechselstromgespeiste Leuchtstofflampe, die mit Heizelementen versehene Katoden und eine induktive Ballastimpedanz in Serie zu der Lampe an der Wechselstromversorgung aufweist, wobei im Betrieb die Zündschaltung zwischen den Katoden der Lampe liegt und wobei die Zündschaltung einen Schalter und eine Steuerschaltung für den Schalter enthält, der abhängig von der Anwesenheit einer Spannung an der Lampe den Schalter veranlaßt, einen Zyklus auszuführen, bei dem die Katoden der Lampe über einen niederohmigen Weg verbunden werden und daraufhin die Verbindung zwischen ihnen mehrmals in einem halben Zyklus der Wechselstromversorgung unterbrochen wird, wodurch die Zündschaltung im Betrieb die Ballastimpedanz veranlaßt, eine entsprechende Folge von Spannungsimpulsen an die Lampe anzulegen.
  2. Schaltung nach Anspruch 1, mit einem Mittel, das abhängig vom Auftreten einer charakteristischen Änderung der Spannung an der Lampe, die das Ansprechen der Lampe anzeigt, die Betriebszyklen des Schalters für zumindest den Rest des betroffenen Halbzyklus der Wechselstromversorgung beendet, in dem die charakteristische Änderung der Spannung an der Lampe auftritt.
  3. Schaltung nach Anspruch 2, bei welcher die Steuerschaltung ein Mittel enthält, das abhängig davon, daß die Spannung an der Lampe einen voreingestellten Wert nicht übersteigt, der anzeigt, daß die Lampe angesprochen hat, den Schalter daran hindert, die Verbindung parallel zur Lampe zu schließen.
  4. Schaltung nach Anspruch 2 oder 3, bei welcher die charakteristische Änderung der Spannung an der Lampe ein schneller Spannungsabfall ist, der eintritt, bevor die Spannung unter einen Schwellenwert absinkt.
  5. Schaltung nach Anspruch 2 oder 3, bei welcher die charakteristische Änderung der Spannung an der Lampe eine Reduzierung der Dauer der Spannungsimpulse an der Lampe ist.
  6. Schaltung nach Anspruch 5, mit einer Zenerdiode, die parallel zu dem Schalter zur Begrenzung der Spannung der Impulse liegt, die von der Ballastimpedanz erzeugt werden, wobei die charakteristische Änderung der Spannung an der Lampe durch ein Mittel festgestellt wird, das auf den Strom durch die Zenerdiode anspricht.
  7. Schaltung nach einem der Ansprüche 1 bis 5, mit einem Gleichrichter, durch den der Schalter und die Steuerschaltung mit den Katoden der Lampe verbunden sind, so daß die Wechselspannung an der Lampe in gleichgerichteter Form an den Schalter und die Steuerschaltung angelegt wird.
  8. Schaltung nach Anspruch 7, bei welcher der Gleichrichter ein Vollweggleichrichter ist.
  9. Schaltung nach Anspruch 7 oder 8, bei welcher der Schalter ein Thyristor ist, der so aufgebaut ist, daß er zur Aufrechterhaltung seines Leitungszustandes einen hohen Haltestrom erfordert oder auf andere Weise die Fähigkeit hat, durch ein an seinen Steueranschluß angelegtes Signal abgeschaltet zu werden, wobei die Steuerschaltung so angeschlossen ist, daß sie einen dem Steueranschluß des Thyristors zugeführten Strom ein- und ausschaltet.
  10. Schaltung nach Anspruch 9 mit einer Zenerdiode, die parallel zum gesteuerten Stromweg des Thyristors geschaltet ist, damit die Spannung der von der Ballastimpedanz erzeugten Impulse begrenzt wird, wenn der Thyristor gesperrt ist.
  11. Schaltung nach Anspruch 10, bei welcher die Zenerdiode in den Thyristor eingebaut ist.
  12. Schaltung nach einem der vorhergehenden Ansprüche, bei welcher die Steuerschaltung ein Mittel enthält, das abhängig von dem ihr über die Ballastimpedanz zugeführten Strom das Öffnen des Schalters anstrebt, wenn der Strom einen bestimmten Wert erreicht.
  13. Schaltung nach einem der Ansprüche 1 bis 11, bei welcher die Steuerschaltung einen Oszillator enthält, der zur Steuerung der Leitfähigkeit des Schalters eine Rechteckwelle erzeugt, deren Frequenz und Tastverhältnis an die Lade- und Entladecharakteristiken einer induktiven Ballastimpedanz angepaßt sind, mit der die Zündschaltung benutzt werden soll.
  14. Schaltung nach einem der vorhergehenden Ansprüche, bei welcher die Steuerschaltung ein Mittel zum Verzögern des Beginns der Schaltzyklen für eine Zeitperiode nach dem Einschalten der Wechselstromversorgung enthält, wodurch sich die Katoden der Lampe vorheizen können, bevor Spannungsimpulse an die Lampe angelegt werden.
  15. Schaltung nach einem der vorhergehenden Ansprüche, bei welcher die Steuerschaltung eine Zeitgeberschaltung enthält, die abhängig von der Zeitperiode, für deren Dauer die Wechselstromversorgung eingeschaltet worden ist, die Schaltzyklen nach einer vorbestimmten Zeitperiode beendet.
  16. Schaltung nach einem der vorhergehenden Ansprüche mit einem Aufbau unter Anwendung der elektrischen Analogschaltungstechnik.
  17. Schaltung nach einem der Ansprüche 1 bis 15 mit einem Aufbau unter Verwendung der digitalen Schaltungstechnik.
EP19870305208 1986-06-13 1987-06-12 Zündschaltung für eine Leuchtstofflampe Expired EP0249485B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB868614470A GB8614470D0 (en) 1986-06-13 1986-06-13 Starter circuit
GB8614470 1986-06-13

Publications (2)

Publication Number Publication Date
EP0249485A1 EP0249485A1 (de) 1987-12-16
EP0249485B1 true EP0249485B1 (de) 1991-06-12

Family

ID=10599434

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19870305208 Expired EP0249485B1 (de) 1986-06-13 1987-06-12 Zündschaltung für eine Leuchtstofflampe

Country Status (3)

Country Link
EP (1) EP0249485B1 (de)
DE (1) DE3770700D1 (de)
GB (1) GB8614470D0 (de)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2194400B (en) * 1986-08-04 1991-04-17 Transtar Ltd Starter and discharge lamp including it
GB8703284D0 (en) * 1987-02-12 1987-03-18 Martin D J Electronic starter for fluorescent lamps
GB8806384D0 (en) * 1988-03-17 1988-04-13 Emi Plc Thorn Starter circuits for discharge lamps
GB2234868A (en) * 1989-07-20 1991-02-13 David John Martin Simplified electronic starter for fluorescent lamps
CH681263A5 (de) * 1990-08-16 1993-02-15 Knobel Lichttech
DE4216716C1 (de) * 1992-05-20 1993-10-14 Siemens Ag Schaltungsanordnung zum Starten einer vorheizbaren Entladungslampe
FR2708811B1 (fr) * 1993-08-06 1995-10-20 Sgs Thomson Microelectronics Thyristor à amplification de gachette à courant de maintien accru.
DE29624405U1 (de) * 1996-10-17 2003-03-20 BISCHL Feinmechanik/Electronic GmbH, 82418 Seehausen Gleichstrom-Gasentladungslampenstarter und Gleichstrom-Vorschaltgerät für eine Gasentladungslampe
EP1051060A1 (de) * 1999-05-07 2000-11-08 Yousef Husni Barikhan Elektronische Schaltung zum Zünden von Leuchtstofflampen und Ähnlichen,mit verbesserten Eigenschaften

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1602456A (en) * 1977-04-18 1981-11-11 Thorn Emi Ltd Starting of discharge lamps
GB8305878D0 (en) * 1983-03-03 1983-04-07 Texas Instruments Ltd Starter circuit

Also Published As

Publication number Publication date
GB8614470D0 (en) 1986-07-16
DE3770700D1 (de) 1991-07-18
EP0249485A1 (de) 1987-12-16

Similar Documents

Publication Publication Date Title
KR950013272B1 (ko) 방전 램프 점등, 고온 재점등 및 작동회로
EP0405715B1 (de) Lampenzündschaltung
US4629944A (en) Starter circuit for a fluorescent tube lamp
CA2388213C (en) Ballast with efficient filament preheating and lamp fault protection
EP0331840B1 (de) Schaltung für eine Hochleistungslampe mit starker Entladung
EP0333359B1 (de) Anlaufschaltungen für Entladungslampen
EP0249485B1 (de) Zündschaltung für eine Leuchtstofflampe
US4673844A (en) Starter circuit for a fluorescent tube lamp
KR830002716B1 (ko) 조명 장치
JP2003532266A (ja) 点弧回路
EP1016332B1 (de) Schaltung zur synchronisierung der zündung von entladungslampen mit elektronischem vorschaltgerät
US5572093A (en) Regulation of hot restrike pulse intensity and repetition
US6153983A (en) Full wave electronic starter
JP2001155878A (ja) 低コストの精密電子式始動器
NZ315657A (en) Process and circuit for striking a high-pressure gas discharge lamp
US4247803A (en) Trigger pulse generator for gas discharge lamps
CN114615774B (zh) 一种漏电保护电路及调光驱动电路
JPS6057676B2 (ja) マイクロ波放電光源用電源装置
GB2194400A (en) Starter & discharge lamp including it
CN101878676A (zh) 用于点燃气体放电灯的方法和点火器
GB2185867A (en) Circuit for starting hot restarting, and operating an HID lamp
JP5579753B2 (ja) ガス放電ランプのための電磁安定器
JPS631569B2 (de)
JPS5838559Y2 (ja) 放電管制御回路
GB2083720A (en) Lamp ignition device

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: A1

Designated state(s): DE FR GB IT

17P Request for examination filed

Effective date: 19880613

17Q First examination report despatched

Effective date: 19900621

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

ITF It: translation for a ep patent filed
AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REF Corresponds to:

Ref document number: 3770700

Country of ref document: DE

Date of ref document: 19910718

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20020610

Year of fee payment: 16

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20020612

Year of fee payment: 16

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20020619

Year of fee payment: 16

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20030612

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040101

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20030612

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040227

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050612