DE3116510A1 - DC voltage starting for gas-discharge tubes - Google Patents

Abstract

The invention relates to a starter circuit for gas-discharge tubes, preferably fluorescent lamps, which makes possible an operating function without the known incandescent electrodes and without any starter (glow-light thermal switch). The starting voltage for gas-discharge tubes is produced, according to the invention, by a stable-current bridge rectifier and by an additional current-limiting voltage cascade which converts the operating AC voltage of, for example, 220 volts, until the start of the gas discharge (ignition) by a multiple into a DC voltage which is reduced once again to the operating value of the fluorescent lamp once starting has been completed. In comparison with the generally known starting method, the starting circuit offers the following significant advantages: 1) No starting delay caused by the heating-up time of the incandescent electrodes and the starter, as well as the possibility of starting repetition (flashing). 2) The light intensity of the fluorescent lamp can be regulated by a series resistor or by a semiconductor, to enable so-called effect lighting systems using fluorescent lamps. 3) The fluorescent lamps according to the invention do not need any incandescent electrodes and these can be replaced cost-effectively by so-called flat electrodes. 4) The starting circuit and the ballast inductor which is required can be integrated in the ballast unit. 5) Series circuits comprising a plurality of fluorescent lamps are possible using only one ballast unit. <IMAGE>

Description

The invention relates to a rapid ignition of gas discharge tubes, . B.

Fluorescent lamps or W lamps with adjustable intensity. Fluorescent lamps and W lamps are so far, according to FIG. 1 via the emission of glow electrodes and ignited a glow-light thermal switch with a series shell of a choke. Technical Details of this circuit technology have been state of the art for decades and therefore do not need any further explanation. Disadvantages of this circuit are Delayed gas discharge after switching on, due to the heating-up time of the glow electrodes possibly repetition of the ignition process (flashing), wear of the glow light thermal switch and wear of the glow electrodes, which ultimately corresponds to the defect in the lamp. With the wear of the glow electrodes, the gas filling is usually before the total defect the fluorescent lamp is contaminated by the emission of the glow electrodes; this shows also optically through single blackening in the area of the two outside Glow electrodes. The frequency of start-ups (switch-ons) is impaired therefore the service life of a conventional fluorescent lamp is quite considerable! It is known that electronic ballasts exist to reduce these disadvantages, which with a relatively large technical effort the fluorescent lamp via a generator operate with a high frequency voltage.

This inevitably gives rise to the problem of radio interference radiation and their elimination. Fluorescent lamps operated in this way also require G1 electrodes for preheating and appropriate electronics for the stagnation process.

The object of the invention is to overcome the aforementioned disadvantages Eliminate life span of fluorescent tubes significantly affect in the on the use of glow electrodes or their intended function: on and on the application a glow light thermal switch is dispensed with.

The solution to this problem is achieved in that the Leuchtstofflarlpe is operated with direct voltage, in which rectifiers and capacitors, according to circuit examples Fig. 2 to Fig. 4 for the ignition he fluorescent lamp a higher DC voltage than the mains voltage is generated. Depending on the dimensions the different fluorescent lamps, e.g. length of the gas line, gas filling and electrical data are different ignition voltages and different operating currents given.

These operating values are also known to those of the mains voltage series-connected choke coil adapted, which after ignition of the fluorescent lamp also acts as a current limiter.

The only exception is miniature fluorescent lamps, e.g. in accordance with Circuit application Fig. 2, with the current limitation through after ignition the alternating current resistance of the two capacitors (7.1) and (7.2) is effected.

Exemplary embodiments of the invention are shown in the drawings: FIG. 1 Conventional circuit for comparing a fluorescent lamp (4) with glow electrodes (1.1 and 1.2), the inductor (3) in series with the power line and the Ignition required glow light Tnermo switch (2).

Figure 2 circuit for a miniature fluorescent lamp with direct voltage ignition, without choke coil. Power is supplied via connections (P) and (O). To the common connection point of the capacitors (7.1 and 7.2) leads to the mains connection (o) and is the basis for two different polarity starting from connection (P) Rectifier sections (6.3 and 6.2). The total voltages of the capacitors (7.1. and 7.2) lie on the electrodes (5.1 and 5.2) of the fluorescent lamp (4.1). To Once the ignition has taken place, this voltage collapses and direct current flows through the Fluorescent lamp whose current is limited by the capacitive resistances of the capacitors (7.1 and 7.2) is effected.

Figure 3 circuit for smaller fluorescent lamps with direct voltage ignition and throttle operation. The supply voltage is applied to the connections (P) and (0), the connection line (P) having a choke coil (3.1) in series and then leading to the common connection point of the diodes (6.3 and 6.5). The opposite pole (O) is at the common connection point of the diodes (6.4 and 6.6). All four diodes (6.3 to 6.6) form a bridge rectifier with the special feature that the diodes (6.4. And 6.6) each have a capacitor (7.3) or (7.4) connected in parallel, through which a direct voltage increase of max.

Volts is reached, i.e. at an operating AC voltage of 220 Volts a DC voltage of approx. 622 volts is created. The output of the bridge circuit leads to the electrodes (5.3) and (5.4) of the fluorescent lamp (4.2). After achieved Ignition voltage breaks due to the load on the gas discharge the instep gsaufstaufung at the capacitors (7.3) and (7.4) together, direct current flows via the fluorescent lamp (4.2), whose current limitation is the same as with a conventional one Circuit, e.g. according to Fig. 1, through the inductive resistance of the choke coil (3.1) is determined. The capacitor (7.4) can also be connected in parallel to the diode (6.3) which means that the DC voltage is maintained before the lamp is ignited, however plus is superimposed with the AC mains voltage.

Figure 4 circuit for large fluorescent lamps with direct voltage ignition and throttle operation. The voltage is supplied via the connection points (P) and (0), the supply line (P), as in the example in FIG. 3, a choke coil (3.2) being connected in series. The bridge rectifier, consisting of the diodes (6.8, 6.9, 6.10 and 6.11) works with the capacitors (7.6 and 7.8) in the same way as in the example in Fig. 3 as a voltage doubler, that is, no-load results between the connection points of the diodes (6.8 and 6.9 ) and the connection points of the diodes (6.10 and 6.11) a DC voltage of Volt, half of which is stored by the capacitors (7.6) and (7.8). With the capacitor (7.5) and the diode (6.7) an additive DC voltage is added, in the example minus Volt increased. In opposite polarization, an additive, positive DC voltage is also increased with the capacitor (7.7) and the diode (6.12). The sum of all DC voltage lines generated in this way thus reaches the value Volt. This voltage is applied to the electrodes (5.5) and (5.6) of the fluorescent lamp (4.3) and causes the fluorescent lamp (4.3) to ignite there. After the ignition voltage has been reached, the gas discharge causes the voltage increase on the capacitors (7.5, 7.6, 7.7 and 7.8) to collapse, and direct current flows through the fluorescent lamp (4.3), which maintains the operating state, with the inductive resistance of the choke coil (3.2) limiting the current causes.

As can be seen from the previous description, need Gas discharge tubes e.g. W lamps and fluorescent tubes with circuit technology of the invention no glow electrodes. Because of this, you can Gas discharge tubes are manufactured in a new design, in which, unlike known fluorescent lamps, instead of the glow electrodes only flat electrodes are used, which are suitable Shaping improves the ignition characteristics.

The omission of the two glow electrodes simplifies the manufacturing process and reduces the manufacturing cost of gas discharge tubes.

Further advantages of the invention are the saving of the glow light switch (Starter), the ability to regulate the light intensity via a series resistor or by means of Semiconductor; electronic rapid ignition without wearing parts; Increase in the duration of the letdown many times over compared to conventional lighting systems, for example for street lighting is of particular importance because there, in addition to safety, the maintenance costs Exceed the nominal value of the wearing parts many times over,

Claims (9)

Subject: DC ignition for gas discharge tubes Patent claims DC ignition for gas discharge tubes, characterized in that the Applied operating AC voltage by consisting of rectifiers and capacitors DC voltage cascode generates a DC voltage which is greater than the effective AC operating voltage and the DC voltage generated in this way is the Electrodes of a gas discharge tube, e.g. fluorescent lamp, is fed to the To cause gas discharge (ignition), after ignition by the relative low-ohmic operating value of the lamp, the ignition voltage collapses and the fluorescent lamp is operated with direct current, the current of which is limited by an ohmic, capacitive, or inductive series resistance in the AC power supply is determined. 2) DC voltage ignition for gas discharge tubes according to claim 1, characterized in that the luminous intensity of a fluorescent lamp by egg NEN additional variable series resistance in the power supply at, weakened will. 3) DC voltage ignition for gas discharge tubes according to claim 1 and 2, characterized in that for controlling the light intensity instead of one Series resistor a controllable semiconductor is used with this achievable Light effect e.g. for advertising purposes or for Licntorgel with several colored fluorescent lamps is used. 4) Equal voltage detection for gas discharge tubes according to the previous ones Claims, characterized in that the circuit examples shown in Fig. 2 to Fig. 4 and especially their components for rush - conversion kit for existing fluorescent lights, in a housing (module) with connectors, terminals or connecting wires are. 5); light voltage ignition for gas discharge tubes according to an or several of the preceding claims, characterized in that specifically ür mass-produced fluorescent lights the components of the circuit at - ;; piele Fig. 3 or Fig. 4 together with the choke coil (ballast solenoid), in one assembly are integrated and two assigned connections for the mains voltage or for have the fluorescent lamp. 6) calibration voltage ignition for gas discharge tubes according to one or more The preceding claims, characterized in that in the case of U-shaped fluorescent lamps, the circuits shown in Fig. 2 to Fig. 3 Imd the associated components in the Lamp holder are integrated. 7) DC voltage ignition for gas discharge tubes according to an or several of the preceding claims, characterized in that specifically at Ultraviolet lamps e.g. for the production of ozone (CO3), the intensity of the lamp electronically controlled continuously or in stages by odor sensors and thereby automatically counteracts the build-up of odors. 8) - DC voltage ignition for gas discharge tubes according to an or several of the preceding claims, characterized in that instead of one Series choke an asynchronous shaded pole motor is used, which is in the operating state the gas discharge tube has an additional rlechanical function. 9) DC voltage ignition for gas discharge tubes according to the previous ones Claims, characterized in that several fluorescent lamps are connected in series and are operated by a common circuit.