DE1010171B - Ignition circuit for at least two discharge lamps or tubes in series with preheated electrodes - Google Patents

Description

GERMAN

The invention relates to an ignition circuit for at least two discharge tubes electrically in series with preheated electrodes.

Circuits are already known for igniting electrical discharge tubes with series-connected preheating electrodes; in which a circuit is connected to the power source in which an impedance,, an ignition relay · and: the two tube electrodes are in series and the series impedance carries a heating current winding for preheating the electrodes. A special ignition relay is provided parallel to the electrodes of each discharge tube. But since neither the discharge tubes nor the ignition relays are completely equal to one another in their "efektnsehen"values; ignites at this- known circuit first only- a ^tube? Then and- goes out, after which ignites the other tube, until eventually ignite both tubes at the same time and remain burning. Therefore, the tubes flicker for some time at each power up, burn them finally together stay.

To facilitate ignition, it is also known to separate the individual electrodes of the discharge tubes Preheat heating coils on the ballast impedance. When several discharge tubes are connected in series But then you need just as many independent heating windings as there are electrodes are what makes the ballast technically complicated and sensitive.

The invention avoids these disadvantages by conducting the following current: From a network pole through the Current limiting impedance and the one outer electrode of the tube series connection to the ignition relay, from the ignition relay through the other outer electrode to the second network pole, the inner electrodes of the Discharge tube series from discharge tube to discharge tube connected in parallel with one another and are fed by one or more mains windings lying on the ballast impedance. Man only requires a single start relay in any case. If more than two discharge tubes are connected in series, then with this circuit you need internal electrodes connected in parallel for each group only one special heating winding on the ballast impedance. The parallel connection of the inner electrodes has the further advantage of a uniform Current distribution to the parallel branches and an even electrode load. The consequence of which is an even distribution of the discharge current of the series-connected fluorescent tubes over the electrode surface and thus a uniform utilization of the electrodes with a result of a prolonged Life of the tubes. In addition, the polarity of the heating winding no longer plays a role, so that

Ignition circuit for at least

two electrically in series

Discharge lamps or tubes

with preheated electrodes

Applicant:
Lumalampan Aktienbolag, Stockholm

Representative: Dipl.-Ing. H. Kosel and Dipl.-Ing. J. Giliard,

Patent attorneys,
Bad Gandersheim, Braunschweiger Str. 22

Claimed priority:
Sweden 6 October 1952

Ake Björkman, Johanneshov,

and Selfrid öhlund, Hagersten (Sweden),

have been named as inventors

you omit the usual test connection on the ballast and thereby the ballast and its Assembly can be cheaper. Another great advantage of the invention is the simplicity of the circuit. A special preheating of the external electrodes and the additional expensive heating windings required for this on the ballast are omitted because the common ignition relay for a powerful induction surge and thus ensures rapid heating of the external electrodes.

Compared to the known circuits with a special ignition relay for each individual discharge tube Another advantage is that only a single ignition relay is used to ignite all of them in series switched discharge tubes is required, which also facilitates the operation of the circuit. The discharge tubes ignite simultaneously without flickering. Because the life of the discharge tubes is a function the number of times it is ignited, the discharge tubes have a longer service life. Used as an ignition relay z. B. selected a glow starter, the result is a circuit with 20 watt fluorescent lamps the advantage that only a single glow igniter in the 220 volt version without activating the electrodes Instead of, as before, two activated glow igniters 110 volts is required. The inactive one

\ y- ~ - '■' ■ "J 709 548/341

Bell fuse is easier to manufacture and more durable than the activated type. The invention can also Use in combination with other known types of ignition relays instead of glow starters.

The invention is explained in the drawing using an exemplary embodiment.

The circuit contains two fluorescent tubes 1 and 4 connected in series with preheating electrodes 2, 3 and 5, 6. Of these electrodes, one end electrode 2 of the tube series is directly connected to a pole 11 of the power source and the other end electrode 6 of the tube series is connected to one end connected to the impedance winding 8, the other end of which is connected to the other pole 12 of the power source. The electrodes 2 and 6 are also connected in series, in series with them an ignition relay 10, in the example a glow starter and a winding 9 known per se in the series connection of discharge tubes on the same core as the impedance winding 8, however is applied with reverse winding direction. This winding 9 and its relationship to the impedance winding gives the preheating circuit with electrodes 2 and! 6 an increased preheating current during the preheating period. However, this winding 9 is in and of itself unnecessary if the air gap of the impedance 8 is set accordingly.

The remaining electrodes 3 and 5 are fed jointly by a heating current winding 7 which is applied to the iron core of the impedance 8 or optionally consists of a part of the impedance winding. The electrodes 3, 5 are fed in parallel.

After the glow starter 10 is closed, the two outer electrodes 2, 6 heat up just as quickly as the two inner electrodes 3, 5 on the opposite side of the heating current winding. By connecting the electrodes 3, 5 in parallel, an emission cloud forms very quickly around each electrode 3, 5 with a transverse arc over the electrodes, which facilitates the ignition of the discharge tubes.

Claims (2)

PATENT CLAIMS: 1. Ignition circuit for at least two discharge lamps or tubes electrically connected in series with preheated electrodes, characterized by the following current conduction: from a mains pole (12) by the current limiting impedance (8) and the an outer electrode (6) of the tube series connection to the ignition relay (10), from the ignition relay the other outer electrode (2) to the second network pole (11), the inner electrodes (3,5) of the Tube series from tube to tube connected in parallel with one another and from one or several mains windings (7) lying on the ballast impedance are fed. 2. Ignition circuit according to claim 1, characterized by one on the iron core of the ballast impedance applied further, opposite winding (9), which with one of the outer electrodes the tube series and the ignition relay is connected in series. Considered publications:
Swiss Patent No. 265 338;
British Patent No. 525 133. 1 sheet of drawings © 709 548/341 6.57