DE1073624B - Ignition and operating equipment for electric discharge lamps with preheatable hot cathodes - Google Patents

Description

The invention relates to an ignition and operating device for electric discharge lamps with preheatable incandescent cathodes, in particular for fluorescent lamps. It is known with such. Discharge lamps in the preheating circuit of the hot cathodes have an ignition switch to be arranged, which is closed in the initial position, and in that of the power terminals, too the main circuit leading the lamp electrodes Parts for opening and keeping open the in the preheating circuit to be provided lying ignition switch.

According to the main patent 1029 476, such an ignition device is thermally retarded Acting organs to open a switch, which bridges the parts connected upstream in the main circuit, provided, wherein the upstream parts control an operating lever that mechanically Both the contact path of the ignition switch in the preheating circuit opens and the contact path of the bypass switch and that of the ignition switch after the lamp has ignited keeps open.

According to the invention, the bypass switch of the ignition device according to the patent 1029476 through such a heat-transferring bimetal strip controlled that the bypass switch about 2 seconds after switching on the Hot cathode preheating current is opened.

The ignition switch itself contributes to the measurement of the preheating time of the hot cathodes its parts lying in the main circuit of the discharge lamp are only insignificant.

Four exemplary embodiments of the invention are shown schematically in the drawings.

Fig. 1 shows the circuit arrangement for · the Ignition devices according to Fig. 2, 3 and 4;

Fig. 5 shows the circuit arrangement for the magnetic ignition device according to Fig. 6.

According to Fig. 1, the ignition devices have an ignition switch S _{1 which} , in the initial position, closes the preheating circuit of the glow cathodes. The actuation of the ignition switch ^ ₁ is caused by a freely stretched hot wire H, which lies in the main circuit, which in turn is bridged by the bypass switch ^. The bypass switch vS " ₂ , the resistance of which is lower than that of the hot wire (e.g. 0.1 versus 5 ohms), is immediately traversed by the preheating current of the hot cathodes after switching on, which is via the choke D, the filament of the lamp L and the closed contacts of the ignition switch S ₁ flows the bypass switch S ₂ is formed by a thermally delaying acting member, such as a bimetallic strip, after some delay, ie, after completion of preheating, opened;.. -es then flows preheating of the overall free by the

Ignition and operating equipment

for electric discharge lamps

with preheatable hot cathodes

Addendum to patent 1,029,476

Applicant:
Gottlieb Widmann & Sons

Limited partnership,
Schwenningen / Neckar, Holzstr. 55/61

Helmut Jedlicka, Sdxwenningen / Neckar,
has been named as the inventor

tensioned hot wire H ₁ which in turn causes the ignition switch S _{1 to open quickly.} The lamp ignites, the operating current, which is smaller than the preheating current, flows from the network via the choke D through the lamp L via the hot wire H back into the network. The hot wire through which current flows, in addition to keeping the ignition switch 6 ^ ₁ open, with the same actuators, also keeps the bypass switch S ₂ open.

In the embodiment shown in Fig. 2, for example, a freely tensioned hot wire 5 controls the switch lever 6 rotatably mounted at 7. A tension spring 13 pulls the switch lever in the direction of arrow 16 until the hot wire is tensioned , so that the switching lever 6 is moved under the action of the spring 13 in the direction 16 and thereby moves the spring 8 with the contacts in the direction of the arrow 15 by hitting the insulating piece 14; the main contacts 9/10 separate, and the contacts 11/12 remain separate. The contact 11 sits on a bimetal strip 17 which is moved in the direction of the arrow when heated. The connections 2 and 3 are contacts of the ignition switch S ₁ in Fig. 1, the connections 1 and 4 those of the hot wire if ¹ in Fig. 1, that of the bypass switch ;; ^ ₂ - here the bimetal contact 11/12 - is bridged.

The mode of operation is as follows: After switching on, the preheating current flows from a mains pole via connection 1, bimetallic strip 17, contact 11/12, connection 4, then via a lamp filament, connection

- "" circuit 2, ignition switch contacts 9/10, spring 8, connection

710/256

End 3, second lamp filament, choke to the second mains pole. The bimetal strip bends after the desired time (z. B. 2 seconds at 220 V, 20 ⁰ C ambient temperature) and lifts the contact 11 from the contact 12 a little, after which the current immediately flows over the hot wire 5, expands it and thereby executes the aforementioned shift lever movement in the direction of arrow 16 when the contacts 9, 10 are opened. At the same moment the lamp lights. The lamp current now continues to flow via the hot wire 5, the contacts 9, 10 and 11, 12 remain open.

If the ignition fails for any reason and no lamp current flows, the switch lever works back to the starting position and closes the contacts 9, 10 of the ignition switch; the process repeats themselves. The bimetallic strip returns to its original position after ignition; he will not heated up during lamp operation.

In the case of the device according to Fig. 3, the principle of operation is the same. The hot wire 5 at the connections 1 and 4 is bridged by the switching lever 6 and the pair of contacts 11, 12 of the bimetallic strip. That When current flows through the bimetal bends in the direction of the arrow 17j, the contact 11 lifts off from 12; the Current now flows through the hot wire 5, which expands, so that under the action of the spring 13 of the Shift lever 6 moved in the direction of arrow 16 while moving the contact spring 8 in the direction -15 and the Contacts 9, 10 of the ignition switch disconnect.

The embodiment according to Fig. 4 works in the same way. Only the contact spring 8 is missing here. The shift lever movement in direction 16 directly separates the contact 12 sitting on the shift lever of the ignition switch from the second contact 11.

In the magnetic embodiment according to FIGS. 5 and 6, instead of the freely tensioned hot wire, a magnetic coil Sp is provided which, when current flows through, spreads the iron springs of connections 2 and 3 in a manner known per se; that is, they move in the direction of the small arrows and thus separate the contact path of the ignition switch S ₁ . The bypass _{switch 5 2} consists of a bimetallic strip which is connected to the terminal 1, so that the bypass switch S _{2 is} briefly separated after switching on and preheating the lamp filaments and only then conducts the current through the coil Sp , which in turn drives the ignition switch S. ₁ opens and holds open. At the same time, the contacts of the bypass switch S ₂ also remain separated, despite the fact that the bimetallic strip returns to its starting position.

Claims (6)

PATENT CLAIMS: 1. Ignition and operating device for electric discharge lamps with preheatable glow cathodes, in which an ignition switch located in the preheating circuit of the glow cathodes is closed in the initial position and in the main circuit leading from the mains terminals to the lamp electrodes parts are provided for opening and keeping open the ignition switch located in the preheating circuit of the glow cathodes are, and with the simultaneous use of thermally retarding agents. Organs for opening a switch that bridges the upstream parts in the main circuit, the upstream parts controlling an actuating lever that mechanically opens both the contact path of the ignition switch situated in the preheating circuit and the contact path of the bypass switch and that of the ignition switch open after ignition holds, according to main patent 1 029 476, characterized in that the bypass switch (S ₂ ) is controlled by such a heat-inert bimetal strip that the bypass switch is opened about 2 seconds after the hot cathode preheating current has been switched on. 2. Ignition device according to claim 1, characterized in that a rotatable lever arm (6), which is not designed to carry current, acts via an insulating intermediate layer (14) on the contact lamella (8) of the ignition switch (S ₁ ) lying in the preheating circuit and the contact lamella (8) insulates the one contact (12) which, together with the contact (11) arranged on the bimetal strip (17), forms the bypass switch (S ₂ ) . 3. Ignition device according to claim 1, characterized in that a rotatable lever arm (6) which is designed to carry current itself carries the contact (12) at its end which, together with the contact (11) arranged on the bimetal strip (17), the bridging switch (^ ₂ ) forms, and the rotatable lever arm (6) acts via an insulating intermediate layer (14) on the contact lamella (8) of the ignition switch (.S _{1) lying in the preheating current.} 4. Ignition device according to claim 1, characterized in that a rotatable lever arm (6) which is designed to carry current itself carries the contact (12) at its end which, together with the contact (11) arranged on the bimetal strip (17), the bridging switch (S ₂ ) forms, and the rotatable lever arm (6) arranged in an isolated manner carries one contact (10) of the ignition switch (S ₁ ) lying in the preheating current. 5. Ignition device according to claim 1, wherein in the leading from the mains terminals to the lamp electrodes. Main circuit a magnet coil of an electromagnetic switch is provided and the magnet coil controls the ignition switch contacts located in the glow cathode preheating circuit, characterized in that the iron springs (2, 3) of the ignition switch (^ ₁ ) are arranged in the magnet coil (Sp ) in the direction of the coil longitudinal axis, so that When the coil is energized, the iron springs (2, 3) magnetizing and spreading the same force occurs, through which the ignition switch (S ₁ ) is opened, and that an iron spring isolates the one contact of the bridging switch (S ₂ ) which has a bimetallic strip. 6. Ignition device according to claim 5, characterized in that the bimetal strip of the bypass switch (S ₂ ) is also passed through the inside of the coil of the magnetic coil (Sp) . Considered publications:
German Patent No. 897 591;
Austrian Patent Specification No. 172 856,173183 ; Swiss Patent No. 288 018; .
British, Patents Nos. 661,791, 738,573. 1 sheet of drawings ® 909 710/256 1.60