FR2811506A1 - DEVICE FOR PRIMING AND SUPPLYING A GAS DISCHARGE LAMP AND LIGHTING APPARATUS INCORPORATING THE SAME - Google Patents

Abstract

The invention concerns a device for starting and powering a gas discharge lamp, connected to an a-c power supply source and comprising connected ballast means and a rectifier circuit. The invention is characterised in that the rectifier circuit comprises two diode bridges (10, 11) whereof the inputs are connected in parallel to the terminals of the supply source and alternately supplying and each in single alternation the ballast means and the discharge lamp. The invention also concerns an illuminating gas discharge apparatus comprising said device.

Description

I The present invention relates to a device for

  starting and supplying a gas discharge lamp.

  It also relates to a lighting device comprising

these measures.

  The invention will find its application in the field of lighting and especially the use of gas discharge lamps. Gas lamps (fluorescent tube, luminescent, mercury vapor, sodium vapor, neon, xenon) with filaments (incandescence, halogen), magnetic (induction) and

  light emitting diodes are thus targeted by the invention.

  Notably, high and low mercury vapor lamps

  pressure or fluorescent tubes are affected by it.

  Currently, it is common to use gas discharge lamps powered from a current source

  alternative for example in 220 volts 50 hertz from the sector.

  To allow the ignition and supply of the gas discharge lamp from such a source, use is made of a

particular circuit.

  In this context, an electrical device is known from document EP-AO.301183 for igniting and supplying a discharge lamp, which device comprises two input terminals intended to be connected to a power source of power; the output terminals of a rectifier bridge are connected in the active state of the lamp to a converter with two input terminals, one of the terminals of which is connected to the other terminal at least via a series connection of a first semiconductor switching element and a charging circuit comprising at least one induction coil and the lamp has

  discharge as well as a connector.

  This type of assembly is not entirely satisfactory.

  First, it uses a selfic system to

  constitute the charge circuit of the discharge lamp.

  The use of inductive elements in the means participating in the ballasting of the discharge lamp has various drawbacks and particularly significant heating as well as electrical disturbances due to the generation of a non-negligible magnetic field. In addition, these inductive systems are often bulky and require the use of components in large numbers. As an example, we often currently use inductive transformer systems or active components such as operational amplifiers or transistors.

to perform the switching.

  The heating generated by inductive systems induces

  also an overconsumption of electrical energy.

  The present invention overcomes the drawbacks

current techniques.

  To do this, it proposes a particularly advantageous device for igniting and supplying a lamp with

gas discharge.

  One of the first objects of the invention is to propose an advantageous circuit for rectifying the signal from the source.

  AC power supply.

  To this end, the invention typically comprises two diode bridges so mounted

specific.

  This particular rectification stage avoids the use of inductors or other more complex systems for the

rectification of the AC signal.

  It allows, by using a limited number of components, to recreate an alternating signal close to the signal coming from the power source and this, while adjusting the amplitude of the signal to the values required for the

  efficient operation of the discharge lamp.

  Another object of the invention is to allow easy adjustment of the operating characteristics of the device and

  a lighting fixture that understands it.

  As such, the choice of the characteristics of simple components (such as the resistance of a piece of polymer or capacity value of a capacitor) makes it possible to adjust the

functioning of the whole.

  Furthermore, the removal of inductive elements and the use of low-level capacitor capacitance values contribute to the properties of the ballasting system constituted by an electrically conductive polymer to the stability of the supply current and the improvement of

circuit power factor.

  This results in a decrease in the power consumed.

  In practice, it has been found that by implementing the present invention, an optimized operation of the discharge lamps is obtained with imperceptible flickering and

  therefore much less fatigue for users.

  Another object of the invention is to allow its incorporation into a lighting device comprising a charged polymer constituting the essential element of the ballast and allowing the improvement of the electrical efficiency and

  increasing the power factor.

  In this regard, the document WO-A-9626628 shows an ignition aid and regulation device for fluorescent tube comprising a piece of charged polymer acting as ballast for the tube with priming aid functions and

  regulating the correct operation of said tube.

  The device presented here can be integrated within the framework of such an ignition assistance device and there will be a perfect complementarity between the device of the invention and

  the device according to this previous document.

  In particular, their combination makes it possible to produce a lighting fixture of limited size by the choice of a ballast of a particular type (a charged conductive polymer)

  and a specific rectifier circuit.

  It will also be noted that, according to the invention, the rectifier circuit with two diode bridges associated with the ballasting means allows them to work alternately, which further limits the losses by Joule effect and promotes the service life.

from the whole.

  Other goals and advantages will emerge during the

  description which follows which is however given only as

code.

  The present invention relates to a device for igniting and supplying a gas discharge lamp, connected to an AC power supply source and comprising ballasting means and a connected rectifier circuit characterized in that the rectifier circuit comprises two diode bridges, the inputs of which are connected in parallel to the terminals of the power source and supplying alternately and each in single-phase

  ballast means and the discharge lamp.

  This device may be presented according to the variants set out below: - two opposite outputs of the diode bridges are connected and the other two outputs are connected in series to the means of

  ballasting and discharge lamp.

  - the ballasting means consist of one or

  several pieces of electrically conductive polymer.

  - The part (s) of electrically conductive polymer is an extrinsic conductive polymer of thermoplastic or thermosetting or elastomeric electric current, charged with electrically conductive particles consisting of carbon black or metallic particles or polymers

intrinsic conductors.

  - the device comprises two capacitors, each placed at the input of a diode bridge and connected in parallel to the

  power supply neutral terminal.

  - one of the diode bridges is connected to the phase terminal of the power source via a capacitor. - the other diode bridge is connected to the phase terminal of the power source via an adjustment piece of conductive polymer. The invention also relates to a gas discharge lamp lighting apparatus, characterized in that it comprises

a device according to the invention.

  This lighting device can be presented in the following embodiment: - it comprises a device according to the invention - it comprises a lamp support provided at its ends with two connection modules for the discharge lamp - the device for priming and supply is integrated in the two modules except the piece of electrically conductive polymer which extends between the two

modules under the discharge lamp.

  The attached drawings are given as indicative and non-limiting examples. They represent a preferred embodiment according to the invention. They will allow

easily understand the invention.

  FIG. 1 illustrates an example of the formation of a diode bridge known as a Graetz circuit operating in a rectifier circuit. FIG. 2 is a particular embodiment of the

device according to the invention.

  Figure 3 is a curve of evolution of the voltage from the two diode bridges over time. The positive part

  and from one of the bridges, the negative part of the other bridge.

  Figure 4 shows an exploded view of an example of

  realization of a lighting device according to the invention.

  The diode bridge rectifier circuits are

  particularly widespread today.

  Figure 1 gives an example in a basic assembly called

from Graetz.

  s According to such a circuit 1, four diodes 2, 3, 4, 5 are present in the bridge in order to rectify an AC electrical signal. The signal obtained at the output terminals 8.9 is then

a continuous signal.

  It is a constant prejudice, according to the state of the art, that the diode bridges used for rectification are used individually. Thus, the rectification stages known at this

  day use only one diode bridge.

  On the contrary, as illustrated in FIG. 2, the device according to the invention has at least two diode bridges called respectively, for the ease of the present

  description, right diode bridge 10 and left diode bridge

  11, according to their arrangement in FIG. 2.

  The device presented here is connected to an AC power source whose terminal

  phase is marked 16 and the neutral terminal 17.

  As a preferred example, a power source constituted by the AC voltage sector 220 Volts at

  frequency 50 hertz may be suitable.

  As also appears in FIG. 2, the device according to the invention supplies a discharge lamp by connection to

its terminals 24.25.

  The two diode bridges 10, 11 which the rectifier circuit of the present device comprises, have an assembly as described below. Their inputs El, E2, E3, and E4 are connected in

  parallel to terminals 16, 17 of the power source.

  The output S2 of the right diode bridge 10 is connected to the

  symmetrical output S3 of the left diode bridge 11.

7 2811506

  The two remaining outputs Si and S4 are connected to the ends of the series circuit constituted by the means of

  ballast and discharge lamp 14.

  In a preferred embodiment, the ballasting means consist of one or more pieces of electrically conductive polymer as shown under the reference

in figure 2.

  We can use a charged conductive polymer material

  of the type as described in the aforementioned document W0.A.9626628.

  They may be extrinsic conductive polymers (made conductive by adding conductive fillers) or

  intrinsic conductive polymers.

  Preferably, the operation of the present device

  avoids any recourse to inductive components.

  In addition, low capacity capacitors

  will suffice for the proper functioning of the discharge lamp.

  On this subject, according to the example of FIG. 2, the inputs E2, E4 of the diode bridges 10, 11 are connected to the neutral terminal 17 of the power source by means of a capacitor respectively, 13, 12 A parallel mounting of the connection of the inputs E2, E4 to the neutral terminal 17 by

  through the capacitors 12, 13 is produced.

  Similarly, the inputs El, E3 of the diode bridges, 11 could be connected to the phase terminal 16 of the

  power source by parallel mounting.

  As shown, the input E3 of the left diode bridge 11 is connected to the phase terminal 16, via a

capacitor 19.

  On the other hand, to allow the adjustment of the light intensity of the discharge lamp (by adaptation of the resistance), the input El of the right diode bridge 10 is connected to the phase terminal 16 by means of a part. 18. Preferably, this adjustment part is made of a conductive polymer material which may, for example, be

  of the same kind as that used for ballast means.

  A safety element such as a fuse 26 can be positioned immediately after the phase terminal 16. This arrangement is such that the diode bridges operate from

  alternately and each one in alternation.

  As shown in FIG. 3, the result obtained is a double full-wave signal, a full half-wave coming from one of the diode bridges, the other half-wave from the

  operation of the other diode bridge.

  The reconstruction of two mono-alternations, one positive and the other negative, makes it possible to recreate, for the supply of the discharge lamp 14, a signal whose shape is close to the signal of the power source while having amplitude characteristics adapted to the proper functioning of

the lamp.

  In addition, the choice of the capacitance values of the capacitors 12, 13 and 19 will allow the operation of the lamp to be adjusted by regulating the power at the inputs

diode bridges 10, 11.

  Similarly, the choice of the adjustment piece 18 will allow the dimming of the light intensity obtained according to the resistance value. It is possible, depending on the desired operating characteristics, to modify the current intensity, the power

  consumed, the power factor and the illumination obtained.

  The invention also relates to a gas discharge lamp lighting apparatus, one embodiment of which is

shown in Figure 4.

  According to this illustration, the discharge lamp 14 is positioned on a support 20 at the ends of which two modules 21 are mounted with connection means for the connection of the gas discharge lamp 14 through its terminals

24.25.

  Preferably, the lamp ignition and supply device is integrated in the two modules 21 except for the piece of polymer 15 which extends along the support

according to the orientation of the lamp 14.

  The electrical connection of the two modules 21 can be ensured, in a current manner, by wires passing under the part

  of polymer 15 or by a printed circuit sheet.

  Finally, a cover 23 can cover the polymer part and the electrical wiring in order to ensure its protection and

  aesthetic nature of the support 20.

  Furthermore, a cover 22 can be attached above the lamp 14 and fixed on the support 20 to form a homogeneous and compact assembly to achieve

the lighting fixture.

REFERENCES

  1. Rectifier circuit with diode bridge 2. 3.4.5. Diodes 6.7. Power terminals 8.9. Output terminals 10. Right diode bridge 11. Left diode bridge 12.13. Capacitors 14. Gas discharge lamp 15. Polymer part 16. Phase terminal 17. Neutral terminal 18. Adjustment part 19. Capacitor 20. Support 21. Module 22. Hood 23. Cover 24.25. Lamp terminal 26. Fuse El.E2: Inputs of the right diode bridge E3.E4: Inputs of the left diode bridge Sl.S2: Output of the right diode bridge S3. S4: Left diode bridge output

Claims (9)

  1. Device for igniting and supplying a gas discharge lamp, connected to a power supply source of alternating current and comprising ballasting means and a connected rectifier circuit characterized in that the rectifier circuit comprises two diode bridges (10,11), the inputs of which are connected in parallel to the terminals of the power source and supplying alternately and each in mono-alternation the means of   ballasting and the discharge lamp (14).   2. Device according to claim 1 characterized in that two opposite outputs (S3, S4) diode bridges (10,11) are connected and that the other two outputs (S1.S4) are connected in series to the ballasting means and at the discharge lamp (14).   3. Device according to any one of claims 1   or 2 characterized in that the ballasting means consist of one or   several pieces of electrically conductive polymer (15).   4. Device according to claim 3 characterized in that the piece or pieces of electrically conductive polymer is an extrinsic conductive polymer of thermoplastic or thermosetting or elastomeric electric current, charged with electrically conductive particles consisting of carbon black or metallic particles or polymers intrinsic conductors.   5. Device according to any one of claims 1   4 characterized by the fact that it comprises two capacitors (12,13), each placed at the input (E2, E4) of a diode bridge (10,11) and connected at   parallel to the neutral terminal (17) of the power source. 12 2811506   6. Device according to any one of claims 1   in 5 characterized in that one of the diode bridges (11) is connected to the phase terminal (16) of the power source via a capacitor (19).   7. Device according to claim. 6 characterized in that the other diode bridge (10) is connected to the phase terminal (16) of the power source via a piece of   adjustment (18) in conductive polymer.   8. Gas discharge lamp lighting apparatus characterized in that it comprises a device according to any one of claims 1 to 7.   9. Lighting apparatus with gas discharge lamp characterized in that it comprises a device according to claim 3   in combination with any of the claims   4 to 7 - it comprises a lamp holder (20) provided at its ends with two connection modules (21) of the discharge lamp (14).   - that the priming and supply device is integrated in the two modules (21) except for the part (15) of electrically conductive polymer which extends between   the two modules (21) under the discharge lamp (14).