DE1589218A1 - Dimmer switch for fluorescent lamps - Google Patents

Description

PATENT LAWYERS

DIPL.-ING. CURT WALLACH

OiPL-ING. GÜNTHER KOCH

DR. TiNO HAIBACH

3 MUNICH 2, 21. 3βρ, 1967 UNSERZElCHENi 1 1 021

LüTRON EIiEOTROiTIOS GOMPAITY, IUC Emmaus, Pennsylvania, T.St.v.A.

Dimmer switch for fluorescent lamps

. The invention relates to a new dimming circuit for fluorescent lamps and especially one novel dimming circuit, in which controlled regulating means of the rectifier type between the power source and the irrimary winding Driss coil are connected.

Circuits for dimming fluorescent lamps are already in place known. Usually such include dimming suitable control means, e.g. adjustable resistors or autotransformers, by means of which the input voltage for the primary winding of the choke coil can be varied the application of such dimming circuits arise serious restrictions because when the tension that is on the inductor is applied is decreased by a small amount a voltage is obtained that is no longer sufficient to enable the fluorescent lamp to generate a light ignite. Therefore stands up to the point in time in which a fluorescent lamp No more light supplies, just a relatively small one

209808/0378

15; 892Ί-8

■ - 2 ■ - "■■ ■; ... '■"

Dim area available. In general the cheapest lies. Dimming% that can be achieved by using the Primary winding of the choke coil has a variable input voltage supplies, on the order of 211 to 5iT, so that this System.in-proves to be inexpedient ""

To dim fluorescent lights? is also already from Controllable ignition devices such as current gates as well as controlled rectifiers have been used «In all cases. however-the control devices between the secondary winding connected to the choke coil and the lamp to be controlled · True can be achieved with the help of such an arrangement useful operating results and a large masking area, but require Such arrangements die.Use special dimming coils and extensive auxiliary facilities ".

However, an even greater disadvantage of these arrangements is that it is ₉ erforderlieh in these known circuits, to connect to the three wire lines Abblendregelvorrichtung ^ This will be discussed in the following näjger. If a dimming device is to be used in connection with an already existing system with two wire lines, it is therefore necessary to lay additional wire lines to the light fittings with the fluorescent lamps *

The invention assumes that it is desirable to have the described regulation with the help of controlled rectifiers to work, which are always connected between the primary winding of the choke coil and the fluorescent lamp, so that

209808/0378 bath

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one obtains a large control range, and furthermore the invention goes: assume that it is desirable to have a dimming device between the primary winding of the choke coil and the voltage source to be provided, which is designed so that it does not it is necessary to provide additional wire lines for a system with two wire lines. According to the invention thus a dimming device of the type that works with controlled rectifiers, connected between the primary winding of the inductor and the voltage source.

. The invention thus provides an arrangement that insofar is advantageous as it is simpler to install and use in existing systems with two lead wires lets'.} the invention also enables an improvement the fade-out ratios, which are controlled when using Rectifiers are available, because of the fluorescent lamp a high voltage pulse is applied even when the applied voltage is low as a device of the type with regulated rectifiers only allows the current to pass intermittently.

A main object of the invention is thus to provide a to create novel dimming device for fluorescent lamps, which makes it possible in a simple and cheap way, a fluorescent lamp quickly down to a very low light intensity to be dimmed.

; Another object of the invention is to provide ^ a new type of dimming device for fluorescent lamps that works with a large dimming ratio

^ - 2Ö9808 / Q37S

easily in existing systems with only two wire lines can be installed.

The invention also provides an apparatus of the type with regulated rectifiers, e.g. an adjustable rectifier or an ötromfcor or the like intermittently conductive device located between the primary winding of the choke coil of a fluorescent lamp and an alternating current network can be connected, and where the choke coil does not need to be trained in any special way.

Further details and advantages of the invention emerge from the following description of several exemplary embodiments on the basis of the drawings.

Pig. Figure 1 shows a typical one constructed in a known manner Dimming arrangement for a fluorescent lamp in which three wire lines must be provided.

Mg »2 shows a construction according to the invention of a dimming circuit for a fluorescent lamp, in which the dimming device has only two connections and provides a large glare-off area »■" .-- ..

Fig. 3 shows the circuit of FIG. 2 in connection with a bypass circuit for the dimming control circuit and an extension cable that could lead to additional primary circuits or other reactors.

FIG. 4 illustrates the waveforms of the voltage of the primary winding of the choke coil and the voltage of the secondary winding of the choke coil in the circuit of FIG. J ₀

2 Ö 9 S Q 8/0 3 7 8

Yy'ig. i> shows the waveform of the lamp current under the controlling action of a gated switch intermittent! 'reads.

.Fig. 6 shows a special ignition lead used in Arrangement according to S'igo 2 or 3 Could be used to make the controlled rectifier to ignite, this ignition cable from a point between the two terminals of the dimming device is supplied with energy. "

. Mg. 7 shows a further embodiment of an ignition control circuit, which could be used in connection with the arrangements according to ü'ig «and 3, with the controlled rectifier are replaced by an Iriac device that has the both terminals of the dimming device is fed »

■■ According to Pig. 1, where an arrangement of known type is shown is, is a power supply network with two lines 10 and 11 provided for a dimming device 12 which is connected to the line 11 in lieihe.

The dimming coil shown in FIG. 1 acts it is a choke coil of known type with a primary winding 13 connected between lines 10 and 11 is, and a winding 14, which is connected to the lines 10, 11 and the fluorescent lamps, which are shown here schematically by a lamp represented in series.

The fluorescent lamp 15 is of known construction and comprises cathodes 16 and 17. The cathode 16 is of a Äbachhitt Ha of winding H is fed while the cathode

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- 6 from a section 13a of the winding 13 is fed.

The dimming circuit 12 can comprise an on and off switch 18 and two controlled rectifiers 19 and 20, the sacks are connected to one another on their backs. The gate circuit formed by the controlled rectifiers 19 and 20 21, 22 is connected to a suitable ignition control circuit 23, which determines the point within each period, at which the rectifiers 19 and 20 are ignited.

The fluorescent lamp 15 is ignited as the windings 13 and 14 form a step-up autotransformer, because of the The lamp 15 also remains with the voltage formed upward ignited after the voltage has been reduced by the regulated rectifier 19 and 20.

With such an arrangement it is possible to achieve fade-out ratios on the order of 20: 1 This known circuit has the serious disadvantage that the dimming device 12 has three terminals 24, 25 and 26 has such a dimming device in an already If the existing system is to be installed with only two line wires, it is therefore necessary to equip the system with an additional To sedge lead wire.

In addition, other screening arrangements have already been proposed and used in which no controlled rectifier elements were used, but in which an autotransformer or the like was provided} In these arrangements, the voltage applied directly to lines 10 and 11

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and thus also applied to the primary winding 13 of the choke coil is lowered by the voltage supplied to the lamp 15 and thus also to regulate the light intensity.

As already mentioned, these arrangements only provide a relative control range before the lamp goes out.

Pig. 2 illustrates the basic idea of the invention, which is based on the knowledge that the one shown in FIG can use known arrangement with controlled rectifiers in known circuits for varying the input voltage, to vary the voltage applied to the primary winding of the choke coil, 'In this novel combination of two well-known Arrangements are obtained, however, a device in which an exceptionally large masking area is achieved, and the can also be used directly with the currently existing systems with only two wire lines.

From j? Ig. 2, where circuit elements shown in Mg corresponding circuit elements are each designated by the same reference numerals, it can be seen that the only one The difference is that the dimming device 12 before Primary winding 13 of the inductor is switched into line 10 is. This apparently only minor modification of the However, switching leads to a very useful dimming device, which is used directly in systems with only two lead wires can be used and provides a fading ratio that see so far at the controllable devices for systems can not be achieved with two lines.

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Pig. 5 shows a further modification of the novel Arrangement according to Fig * 2, in which a radio interference suppression capacitor 30 and a damping resistor 31 are provided in the form of a series circuit, which are connected in parallel with the dimming circuit 12 Furthermore, FIG. 3 shows that a further line 32 is provided for additional inductor primary windings can, wherein the only existing dimming device 12 is used to dim a plurality of individual fluorescent lamps.

Yfenn the controlled rectifier with the primary winding the choke coil are connected in series, causes the sharp Switching characteristics of the regulated rectifier or equivalent devices that on the lamp 15 a voltage spike appears to ignite the lamp * This inductive voltage peak appears at all ignition angles of the controlled Rectifiers 19 and 20, yes, she wins her special Significance with small ignition angles * where the peak voltage onae the additional conductivity peak is low.

This is best seen in Figure 4, where the waveform 40 represents the voltage applied to the primary winding 13, while the waveform 41 with the additional voltage peaks the voltage appearing on the secondary winding 14 represents. Regarding the setting of the ignition can be assumed that the light intensity is as low as possible is set, of which it has been shown to be uniformly of the order of ■ 1 $ of the full light intensity of the Lamp 15 corresponds.

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If necessary, the rectifiers 19 and 20 can be replaced by gate-controlled switches which are connected in series with the choke coil. With these gate-controlled Switches are devices that are activated by a suitable Signal can be switched on and off according to the Control element of a controlled rectifier is fed. A gated switch, such as a switch of the type IIX-120AÖ from Texas Instruments can use one of the The appropriate signal supplied to the gate is switched on and off while a controlled rectifier of the usual type with the gate is switched on and by interruption of the anode current, is switched off. Such a device can also be compared to the unilateral controlled rectifier be bilateral.

* There is a fundamental property of fluorescent lighting in the fact that their light output corresponds to that flowing through them Arc current is directly proportional. If e.g. the gate-controlled Switch would be caused to switch the current on and off in the manner shown in FIG Current decreased, and as a result the average light output would be decreased. The dimming is achieved by varying the mean current flowing through the lamps will. Again there are inductive voltage peaks on the leading edge of the conductivity section introduced so that the The lamp is ignited even at low voltage levels »In addition, the light output in lumens decreases with fluorescent lamps Watts directly proportional to frequency too. Since switching the power on and off several times during a period

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has the same effect as increasing the frequency see an economic use of the light output per watt, i.e. the same amount of electricity produces a greater amount of light.

It should be noted that at this point a sufficient Operating voltage for the heating elements 16 and 17 of the lamp must be available, although this is the point at which the root mean square value of the voltage is a minimum. For example the windings 13a and 14a on the heating elements, at this point the lowest regulated voltage will bring a voltage of 1 to 2 V into effect, with the arc current is on the order of 0.05 to 2 milliamperes.

It should also be noted that the regulated rectifiers or equivalent regulated devices provide a holding current which is smaller than the weakest current, which is absorbed by the choke coil and the lampi

To ensure a long service life for the fluorescent lamps, the voltage applied to the heating elements must not increase too much, nor must it be too low will? preferably it should be at the time of ignition of the arc are in the order of 2.5 volts. According to the invention, however, that applied to the heating elements varies Voltage when the dimming device-the applied voltage regulates »so that one trained in any known way, a constant voltage supplying means must be provided for the heating elements in order to prevent excessive voltages

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be applied to the heating elements. For example, saturable choke coils formed in a known manner can be used with the heating elements in parallel, these reactors saturate after they have reached a certain number of Yolt seconds has been supplied. Alternatively, it is in the in Fig. 3 indicated with dashed lines «/ otherwise possible, Auxiliary voltage sources 16a and 16a which supply constant voltages 1? A to be connected to the filaments .16 and 17.

As already mentioned, a capacitor 30 is provided to effect radio interference suppression of the device. Such a capacitor can in a typical case have a capacitance of the order of 0.05 microfarads. However, since this capacitor can resonate with the inductance of the choke coil, so that vibrations are created through which the anti-glare effect is disturbed or frustrated, the vibrations are preferably suppressed by that switched to the capacitor 30 has a small resistance 31 in series \ of The resistance value of this resistor could be in the order of magnitude of 100 ohms. Of course, other vibration damping means could also be used.

Referring to Fig. 6, the details of the ignition circuit 23 are 2 and 3 shown in the dimming device 12 is included and over the two clamps of the dimming device is fed. In Fig. 6, circuit elements shown in Figs. 2 and 3 are corresponding circuit elements each denoted by the same reference numerals. According to 6 is the line 10 into which the on and off switch 18

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is switched on, as corresponds to FIG. 2, with the radio interference filter provided, which comprises the capacitor 30 and the resistor 31

Fig. 6 also shows a special ignition circuit for the controlled rectifiers 19 and 20, which are a series circuit which consists of two capacitors 50 and 51 » a variable resistor 52 and a fixed resistor 53 composed} this series connection is connected in parallel with the controlled rectifiers 19 and 20. The capacitors 50 and 51 are bridged by a diode 54 and 55, respectively. A fixed parallel resistor is connected to the variable resistor 52 56 and an adjustable resistor 57 connected · Common sliding contacts 5öa, which with the help of a suitable Button are used to set the resistance value of the variable resistor, the adjustable resistor 57 being a trim setting of the resistor 52 allows. The junction between capacitor 50 And the resistor 52 is in trigger order with one end 58 connected to the resistor 59 and the gate electrode of the controlled rectifier 20 is connected in series. The node between the resistor is accordingly 52 and your capacitor 51 connected to the trigger assembly 60, which is connected in series with the resistor 61 and the gate of the controlled rectifier 19. the The entire arrangement shown in FIG. 6 is connected in series with a choke coil 62.

BATH 209808/0378

When the arrangement according to FIG. 6 is operated, the capacitor is used 50 and; the variable resistor 52 as a phase control circuit, by means of which the ignition point of the controlled rectifier 20 is adjusted by causing a pulse is fed to the gate of the controlled rectifier 20 as soon as the voltage at the node between the Node between the capacitor and the variable Y / resistor 52 reaches a predetermined value. The controlled one Rectifier 19 is controlled in a corresponding manner via a phase control comprising capacitor 51 and trigger arrangement 60 circuit triggered.

It should be particularly noted that the ignition circuit according to Pig. 6 arranged between the two within the masking device Terminals is because of the various circuit elements the mains voltage is supplied up to the point in time at which the relevant rectifiers are ignited after the relevant circuit elements have been ignited, the control circuit requires during the remaining part of the Half cycle no voltage. As soon as the half-period for §en relevant control rectifier has ended, the voltage reappears during the next half cycle at the for Phase control serving circuit elements to prepare the device for the next ignition process.

Useful results are obtained when the elements of the circuit according to I ¹ Xg. 6 have the electrical ratings listed below.

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Capacitor 30 Capacitor 50 Capacitor 51 Resistor 31 Resistor 52 'Resistor 53 s / Resistor 56 Resistor 57 Resistor 59 Resistor 60 Diode 54
Diode 55
Trigger diode 58 trigger diode 60

0.05 microns, 200 yoIt 0.1 microfarads, 200 volts 0.1 microfarads, 200 volts 150 ohms

700 kilohms

2.2 kilohms

220 kilohms

2 megohms

150 ohms

150 ohms

Type IN485

Type ΙΪΤ485

Type (G.E.) ST 2X 5 Type (G.E.) ST 2X 5

Controlled rectifier 19 type (G.E.) C22B Controlled rectifier 20 type (G.E.) C22B inductor 62 25 microhenry, 5 amps

Pig. 7 shows a circuit similar to that of Pig. 6, with a triac device 70 instead of the back rectifiers 19 and 20 connected to one another at the back after Pig. 7 is used. In Pig, 7 are in Pig. 2, 3 and 6 Circuit elements corresponding to the circuit elements shown are each denoted by the same reference numerals} the circuit after Pig. 7 is connected in series with the on and off switch 18, and it is again a series connection connected in parallel with it provided, which comprises a capacitor 30 and a resistor 31.

209808/0373

Referring to Fig. 7, the triac device 70 is with the choke coil 62 connected in series according to FIG. 6, and a symmetrical one Ignition circuit for the triac device 70 comprises a trigger diode 71 »which via a resistor 72 with the Phase locked circuit is connected, which has a capacitor 73, resistors 74 and 75 and two potentiometers 76 and 77 scope. The circuit according to i'ig · 7 operates in the manner that an adjustment of the main setting resistor 76 a phase shift causes the voltage appearing at the junction between the Yiaerstand 76 and the capacitor 73, so that the trigger diode 71 allows an ignition pulse to pass through each half cycle, depending on the extent of the phase control which is desired when the triac device 70 is ignited is to achieve the desired glare effect.

In the case of FIG. 7, expedient circuit elements with the electrical ones listed below are used iVerten uses »

Capacitor 73 0.05 liicroiarad, 200 volts

Resistance 72 150 0hm

Resistance 74 1 kiloohm

resistance 75 iOO kiloolim

Potentiometer 76 115 Liloohm Trimmer potentiometer 77 1 megohm

Tri _{6 er} diode 71 type (& .E.) ST 2X 5

iriac device 70 type. (. &. £;.) 2J 257/285

Choke coil 62 25 /.likronenry, 5 amps

ORIGINAL BATHROOM 209808/0378

.. It should be noted that one of the above-described Execution examples the most diverse changes and modifications can provide without departing from the scope of the invention.

Claims ;

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Claims (10)

PA Ϊ E H TAU S PE U GHE 1 «) lamp dimming position, marked by a fluorescent lamp (15), a choke coil (13, 14), a light dimming device, from which a first and a second line (10, 11) extend as the only electrical connections, as well as a? / echselstromnetz with a first and a second terminal, the first terminal being the first line of the light dimming device, the choke coil and the wide AC voltage terminal form a first! series circuit, where- " in the case of the light dimming device between the first AC voltage terminal and the reactor is connected, the second line being connected to the reactor, wherein the fluorescent lamp bypasses the choke coil, whereby the Liehtabblendvorriehtung an adjustable conductive device includes j by means of which the length of the tent span is regulated, during which a current during every half cycle of the alternating voltage source can flow through these means, whereby the fluorescent lamp is provided with cathode threads (16, 17), and wherein the choke coil comprises a secondary heating coil (13a, Ha) extending therefrom and connected to the cathode filaments connected is, 2. light dimming circuit according to claim 1, characterized in that g e that the controllable conductive means are controlled rectifiers (19, 20) » 209Ö08 / Q378 3. Lichtabblendscnaltung, geke η η ζ calibrated by a fluorescent lamp, a choke coil, a light dimming device * from which a first and a second line extend as single electrical connections, as well as an alternating current network with a first and a second terminal »whereby the first Terminal, the first line of the light dimming device, the choke coil and "the second AC terminal form a first line circuit, the light dimming device being between the first AC terminal and the choke coil, the second line being connected to the choke coil, the fluorescent lamp bridging the choke coil, where the light dimming device comprises a first and a second controlled rectifier connected back to back and connected in parallel to each other, the fluorescent lamp comprising cathode filaments, the choke coil comprising a secondary heating coil extending from the choke coil extends and is connected to the cathode filaments, and wherein the LichtblendvorrichtuBg has two terminals _a which are formed by the first and the second line * 4 "Liehtabblendschaltung to Hegeln" _s which is applied via a first and a second AC power line to the choke coil of a fluorescent lamp of the voltage ge - ■ characterized by a controllable switching element which are operated li & nn $ to AE® to iron adjustable point during each Hallperiod® r & ®r the first and the second alternating current line, the alternating voltage discharged essentially instantaneously to become _{conductive s} whereby the controllable switching " ■ ..., ...- .., tfteeo.0 / 6378 BAD ORK3INM- processing element has first and second terminals, the first terminal being connected to one end of the first AC line, the second terminal being connected to a first portion of the inductor, with one end of the second electrical current line being connected to a second portion of the inductor wherein a fluorescent lamp is connected to the choke coil of the fluorescent lamp, the fluorescent lamp comprising cathode filaments, and the choke coil comprising a secondary heating coil extending therefrom and connected to the cathode filaments _e 5 ο light dimming position to control the voltage that is applied to the choke coil of a fluorescent lamp from a first and a second alternating current line, g. eke η η ζ eic h η et by a controllable circuit element which can be actuated to become conductive at an adjustable point during each half cycle of the alternating voltage applied to the first and second alternating current lines, the controllable circuit element being a first and a second terminal, the first terminal being connected to one end of the first AC line, the second terminal being connected to a first portion of the choke coil, one of the side of the choke coil being connected to a second portion of the choke coil, the controllable Circuit element comprises a triac device, a fluorescent lamp being connected to the choke coil, the fluorescent lamp comprising cathode filaments, and a secondary heating winding connected to the Xathdideni filaments extending from the choke coil. - -, 209808/03 7 8 BAD original 6. Lichtahblendaltung to regulate the one first and second AC line from voltage applied to the choke coil of a fluorescent lamp, characterized by a controllable circuit element, which can be actuated to at an adjustable point during the half cycle of the to the first and the "second." AC voltage applied to alternating current line to become conductive essentially instantaneously, the controllable A circuit element comprises first and second terminals, the first terminal being connected to one end of the first AC line, the second terminal being connected to one end first part of the choke coil is connected, one end of the second AC line with a second part of the choke coil is connected, the choke coil comprising a primary winding and a secondary winding, the first and the second part of the choke coil each by an end section the primary winding is formed, the primary winding, the secondary winding and a fluorescent lamp being closed Form a circuit with the fluorescent lamp Comprises cathode filaments, and wherein the choke coil has a secondary extending therefrom and connected to the cathode filaments Heating coil includes 7. Iiichtabblendaltung to control the from a first and a second AC line out to the reactor a fluorescent lamp applied voltage, g e k e η η draw t by a controllable circuit element connected in series with the choke coil of the fluorescent lamp is and can be actuated to at an adjustable point 209808/0378 each Halbperib.de'-which to the first and the second alternating current- - AC voltage applied to the line essentially instantaneously be made conductive or non-conductive. . 8. ■. . Light dimming circuit for regulating the from a first and a second Weohselstromleitung out to the reactor voltage applied to a fluorescent lamp, g e k e η η ζ e i ch net by a controllable circuit element that connected in series with the choke coil of the fluorescent lamp is and can be actuated to at an adjustable point each half cycle of the to the first and second AC power lines applied alternating voltage essentially. instantly to be made conductive or not conductive, whereby the controllable element comprises a gate-controlled switch, and wherein the gated switch has a holding current, which is lower than the weakest current produced by a fluorescent lamp connected to the choke coil must be conducted to keep the lamp in the conductive state ssu keep. 9. Light dimming circuit for regulating the voltage applied to the choke coil of a fluorescent lamp from a first and a second AC line, g © ke η η ζ ei ch η et by a controllable Söhalteelement that can be operated to at an adjustable point of each half cycle AC voltage applied to the first and second AC power lines to be rendered substantially instantaneously conductive, the controllable circuit element comprising a first and a second terminal _f , the. first terminal connected to one end of the first AC power line . 200808/0378 wherein the second terminal is connected to a first part of the choke coil connected, a fluorescent lamp to the choke coil is connected, the fluorescent lamp comprising cathode filaments, the choke coil extending from one to the other. her off extending secondary heating coil connected to the cathode filaments, one end of the second AC line is connected to a second part of the choke coil, and wherein the controllable circuit element with a holding current works, which is weaker than the current, which in every regulated operating state through the fluorescent lamp and the Choke coil flows. 10.. Light blocking circuit according to Claim 1, characterized by the controllable conductive means directly bridging high-frequency filter means which comprise a capacitor and a damping resistor connected in series " - 11 Liohtabblenaschaltung sum control of the voltage applied from a first and a second alternating current line to © ine fluorescent lamp, characterized by a controllable Schalimjsgöelemsnt that is connected in series with the fluorescent lamp and can be operated to set each half-period of the aa the first and the second feehaelatromlsituag applied alternating voltage is made conductive baw _e not made conductive au wex-den. aoaaea / om Blank page