JP2007265902A - Electrodeless discharge lamp and luminaire using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp device which surely starts lighting when collectively lighting a plurality of arc tubes and reduces a loss in a lighting circuit. <P>SOLUTION: Induction coils 102 and 103 are arranged in a plurality of arc tubes 111 and 112 respectively, and the coils arranged over the arc tubes 111 and 112 are connected to each other in series when viewed from power source side. Thus, the startability at the time of multi-lamp lighting is improved and the loss in the lighting circuit is reduced. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrodeless discharge lamp apparatus of a type in which a discharge is generated and maintained by an induction electric field using a high frequency without mounting an electrode inside the discharge vessel. Moreover, it is related with the lighting fixture by which an electrodeless discharge lamp apparatus is mounted.

  In response to the recent social background of energy saving and resource saving, it is desired to develop a lamp having a longer life and higher efficiency. As a lamp that meets such demands, it is characterized by the fact that no electrode is used inside the discharge vessel space, especially for facilities requiring high maintenance-free requirements, outdoor lighting, or special applications such as UV (ultraviolet) use. Electrodeless discharge lamp devices are being put into practical use.

  At present, in fluorescent lamps and high-intensity high-pressure discharge lamps that are widely used as light sources for general illumination, deterioration of electrodes and filaments with the passage of lighting time is the largest factor that limits the life. An electrodeless discharge lamp having no electrode inside the discharge vessel space can be expected to have a long life because there is no deterioration factor as described above. Moreover, in order to make this electrodeless discharge lamp popular for general illumination, it is realized in the form of a thin and long linear light source, similar to the straight tube type fluorescent lamp that is most popular as the current illumination light source. It is hoped that. This is because the existing straight tube luminaires are most frequently used, with uniform light emission (luminance) in the tube axis direction, fixture efficiency (light extraction efficiency from the luminaire), and light distribution control. It is because it is excellent in.

  A conventional electrodeless discharge lamp for realizing a long and narrow light source includes a plurality of induction coils wound around a discharge vessel, and an induction electromagnetic field generated by supplying a high-frequency current to the coils. Some of these ionizable gases are ionized and discharged to maintain a stable plasma (see, for example, Patent Document 1).

  FIG. 10 shows a conventional electrodeless discharge lamp device described in Patent Document 1. In FIG.

  In FIG. 10, the discharge vessels 1101 to 1104 are hermetically sealed with a light-transmitting material. Usually, glass materials such as soda lime glass, borosilicate glass, and quartz glass are selectively used depending on the use of the light source. Yes. A rare gas such as mercury and krypton (not shown) is sealed inside the discharge vessel to realize an arc tube. For general lighting applications, in order to convert ultraviolet rays radiated by discharge into visible light, phosphors are applied to the inner walls of the discharge vessels 1101 to 1104 to realize an arc tube.

  The induction coils 1105 to 1108 are wound around the discharge vessels 1101 to 1104, respectively, and are installed in a line in the elongated outer tube 1109 with the longitudinal direction as an axis. The induction coils 1105 to 1108 are connected via a matching circuit for impedance matching with the load side so that power is supplied from the high-frequency power source to the induction coil (both not shown).

  The high frequency power source is configured by an inverter circuit that converts electric power supplied from a commercial power source into a high frequency of several tens of kHz to several tens of MHz, and supplies the induction coils 1105 to 1108 with high frequency power.

  The electrodeless discharge lamp apparatus configured as described above has been devised mainly for special applications such as UV germicidal lamps. For that purpose, one or a plurality of electrodeless discharge lamp apparatuses are used in order to irradiate ultraviolet rays uniformly and widely. Each discharge vessel is arranged in a straight line inside a straight tubular outer tube. Usually, in this type of field, a straight tube-shaped sterilization lamp provided with an electrode in a discharge tube is often used, which imitates the general form.

  In the electrodeless discharge lamp apparatus as shown in FIG. 10, induction coils 1105 to 1108 generate a high-frequency electromagnetic field by a current supplied from a high-frequency power source (not shown) at the start of discharge, and the induction coil is generated in the discharge vessel 1101. In the vicinity of the winding where the electromagnetic field generated from 1105 to 1108 is the strongest, a discharge seed is generated (a weak discharge with a low plasma density called E discharge: hereinafter referred to as E discharge).

  Further, the induction high frequency electromagnetic field induced in the discharge vessel 1101 accelerates the ionization of the enclosed rare gas and mercury atoms, thereby forming a discharge ring plasma concentric with the induction coils 1105 to 1108, and the induction coil 1105. Energy can be efficiently transferred from ~ 1108 to plasma (discharge with high plasma density called H discharge: hereinafter referred to as H discharge).

  In this way, mode jump is performed from the weak E discharge having a low plasma density to the H discharge having a plasma density of about one digit higher. In the plasma, mercury atoms are excited to resonance levels by electrons, and ultraviolet rays are mainly emitted when the excited mercury atoms are deexcited to the ground state. Among the ultraviolet rays, a resonance line mainly having a wavelength of 253.7 nm is irradiated as it is when UV light such as a sterilizing lamp is used, and in a general illumination application, a phosphor layer (applied to the inner walls of the discharge vessels 1101 to 1104 ( (Not shown) is converted into visible light.

  In the region of E discharge, since the plasma density is generally low, the amount of ultraviolet radiation required for light emission is relatively low and is not used as a discharge form of a lamp. Furthermore, since the voltage applied to the induction coil is high and the current value flowing through the coil is also high, the loss in the coil portion is large. Therefore, the heat-resistant life characteristic of the coil is reduced due to heat generation in the coil, and the reliability against dielectric breakdown between the coil windings is reduced. Furthermore, since it is necessary to supply a larger current and voltage to the induction coil, the electrical stress applied to the matching circuit section is increased. As a result, the life and reliability of the lighting circuit are significantly reduced. Therefore, the area actually used as a lamp is the above-described H discharge.

  The H discharge is a system in which the plasma ring formed in the discharge vessel is regarded as a secondary side coil and can be regarded as a transformer that performs mutual induction with the primary side induction coil. In general, the H discharge requires a low voltage applied to the induction coil, and the current value flowing through the coil is low, so that the reliability of the coil and the circuit element is high. For this reason, all the products that are commercialized as electrodeless discharge lamp devices with a high output of several tens of W to several hundred W use this H discharge.

  The form of the light source using this H discharge can be roughly classified into the following three types A to C.

  (A). This is a system in which an induction coil is wound around the outer surface of a substantially spherical or cylindrical discharge vessel, which is an arrangement of the discharge vessel and the induction coil of FIG. 10 described above.

  (B). This is a form in which an inner recess is provided in a substantially spherical or cylindrical discharge vessel, a coil is wound around a cylindrical (or columnar) magnetic core in the inner recess, and an induction coil is inserted.

  (C). An induction coil (Tokumaku-shaped) made by winding a coil around a magnetic core shaped like a katakana “ro” -shaped or circular tube fluorescent lamp and covering a part of the discharge vessel It is arranged.

  In the electrodeless discharge lamp apparatus having the configuration shown in FIG. 10, induction coils each wound around a plurality of discharge vessels are connected in parallel. As a result, the voltage applied to each induction coil is equalized with respect to the output voltage from the circuit side, and there is an effect that the light emission of the discharge by the induction electric field is made uniform during steady lighting. However, at the time of starting lighting, it is rarely that all the arc tubes start lighting at the same time due to variations in manufacturing characteristics such as the discharge vessel, the enclosure, and the induction coil.

  At the time of starting the lamp, current passes through the weak plasma in the discharge space when E discharge occurs. That is, since the current path is increased, the current flowing through the induction coil is substantially reduced. Therefore, the induced electromotive voltage generated at both ends of the induction coil is reduced accordingly. If the induction coil is connected in parallel, the induction coil wound around the arc tube that has started E discharge earlier will be dragged to the other arc tube (the arc tube that has not even started E discharge). The electromotive voltage of the wound induction coil is also reduced. That is, the voltage applied to start discharge is reduced, which is disadvantageous for starting.

  Furthermore, in the H discharge, the induced electromotive voltage applied to both ends of the induction coil is greatly reduced due to the coupling (mutual inductance) with the generated plasma (usually 1/3 to 1/5 of the E discharge). Therefore, other arc tubes (the arc tubes that have not started discharge) cannot obtain the voltage required for discharge from each induction coil, and the lighting startability (especially, transition from E discharge to H discharge) Or the lighting start (transition to H discharge) cannot be performed. Therefore, extreme stress is given to the induction coil and the circuit element (reduction in reliability and life).

  This phenomenon is particularly remarkable for the C-type Tokumaku electrodeless discharge lamp as a result of the experimental comparison and examination of the present inventors in the three-type electrodeless discharge lamps A to C described above. It turned out that it was difficult to light up uniformly. The reason is that since the toroidal core is used, the magnetic flux excited by the induction coil becomes almost a closed magnetic circuit (there may be a small gap in part of the core), and in the loop of the closed magnetic circuit, This is because the entire loop-shaped discharge current formed by the plasma pushed into the closed-loop discharge vessel passes in a completely interlinked manner, so that the energy coupling with the plasma becomes very good. it is conceivable that. Therefore, in the Tokumaku method, the influence of mutual inductance with plasma due to H discharge is larger than that in the A and B methods, and the degree of decrease in electromotive voltage induced in the induction coil after lighting is increased. Since the A and B systems are open magnetic paths, the coupling performance is significantly lower than that of the Tokumaku type, which is considered to be because the degree of influence is small.

  As a result of an experiment in which a single arc tube is lit with an input power of 30 to 100 W for comparison of the three systems, the present inventors have found that in terms of the coupling coefficient of the transformer, = 0.8 to 1.0, and in the other two systems, | k | = about 0.5 to 0.7 (the coefficient depends on the arrangement of the induction coil, the shape of the discharge vessel, and the difference in the electric power supplied to the arc tube. It was found that it changed slightly). In other words, in the Tokumaku method, the energy transfer efficiency to the arc tube is extremely high and it is easy to obtain efficiency, but on the contrary, it is easily affected by the mutual inductance due to the inductance component formed by the plasma, before and after the transition to H discharge. The impedance characteristics of the load (induction coil and arc tube) are greatly changed.

  For this reason, in the conventional electrodeless discharge lamp apparatus having the configuration shown in FIG. 10, a plurality of discharge containers are used particularly in an electrodeless discharge lamp apparatus having high energy coupling, such as the Tokumaku system having a loop-shaped discharge container. In order to turn on the lamp, the arc tube that has not started discharge is detected, and a new start-up induction coil is separately installed in the induction coil disposed in the detected arc tube to discharge the discharge. Special feedback control and mechanism, such as starting, is indispensable, which increases the size and cost of the device.

  On the other hand, regarding the shape of the plasma formed in the arc tube, in the above two methods, a ring-shaped plasma concentric with the induction coil is formed inside the induction coil or inside the discharge vessel disposed outside. A current loop is formed. Therefore, in these two systems, only a part of the arc tube parallel to the induction coil (a little wider than the width of the induction coil because plasma diffuses) corresponds to the width of the coil in which the induction coil is disposed. Does not emit light.

  In these two methods, in order to make the elongated discharge tube emit light over the entire length, an induction coil is wound over the entire length, or a plurality of arc tubes around which the induction coil is wound are arranged in a daisy chain. There is no choice but to do. Therefore, in the case where the induction coils 1105 to 1108 are wound around the outer surfaces of the discharge vessels 1101 to 1104 as shown in FIG. 10, the light emitted from the arc tube is blocked by the induction coils 1105 to 1108, and the light extraction efficiency is reduced. Will fall. Furthermore, since a magnetic core such as ferrite cannot be used structurally, in order to generate a discharge, a larger current must be passed through the induction coil or the number of turns of the coil must be increased excessively. Cannot be induced, and an induced electric field cannot be induced in the tube.

  In addition, as shown in FIG. 10, since the induction coils 1105 to 1108 are connected in parallel, the output current from the lighting circuit is shunted and reduced, so it is necessary to increase the current flowing through the original lighting circuit. is there. For this reason, the loss in the lighting circuit is further increased, and the efficiency of the discharge lamp device (system) is significantly reduced. Therefore, it is not suitable as a facility for which efficiency is required or a light source for indoor and outdoor illumination.

On the other hand, in the Tokumaku method, since a magnetic flux passing through the toroidal core and a loop-shaped discharge tube are linked, a loop-shaped discharge current flows along the discharge vessel. That is, the loop-shaped discharge vessel has the shape of a ring-shaped plasma as it is, and the entire discharge tube can emit light regardless of the width of the induction coil. For that reason, the Tokumaku electrodeless discharge lamp is most advantageous, but the discharge path (current loop) becomes extremely long compared to the other two methods, and the impedance of the discharge plasma (plasma resistance component, Further, since the inductance component becomes high, it is difficult to maintain the discharge. As the length of the line light source is increased, it becomes more difficult to maintain the discharge. Furthermore, in order to maintain discharge, a large current must be supplied to the induction coil, increasing the loss in the induction coil and reducing the efficiency. For this purpose, it is considered to be more realistic and advantageous to divide into arc tube lengths that are easy to maintain discharge and to arrange a plurality of arc tubes to realize a linear light source. As described above, turning on multiple lamps is accompanied by difficulties related to discharge startability.
JP 2001-167739 A (see FIG. 11)

  As described above, in the conventional configuration, since the induction coils 1105 to 1108 wound around the plurality of discharge vessels are connected in parallel, the manufacturing characteristics of the discharge vessel, the enclosure, the induction coil, etc. at the start of lighting. Due to the variation, there is a problem that all the arc tubes do not light at the same time or some arc tubes cannot be lighted.

  Further, in order to achieve stable lighting, the current flowing through the induction coils connected in parallel has to be increased, which causes a problem that the loss in the lighting circuit increases and efficiency decreases.

  In view of the above-mentioned problems, the present invention provides an electrodeless discharge lamp device in which a plurality of light-emitting tubes in a loop are easily lit by a single lighting circuit, and the starting performance and the efficiency in the lighting circuit are improved. With the goal.

  In order to solve the above-described conventional problems, an electrodeless discharge lamp device according to the present invention is made of a light-transmitting material, and includes a plurality of inclusions made of at least metal vapor and a rare gas. A discharge vessel, at least one induction coil disposed in each discharge vessel so as to induce an induction high frequency electromagnetic field in a discharge space inside the discharge vessel and discharge the inclusion, and a high frequency in the induction coil An electrodeless discharge lamp lighting device comprising: a high-frequency power source for supplying power; and a matching unit including a resonance circuit that performs impedance matching between the induction coil and the high-frequency power source, the induction coil The induction coils arranged in different discharge vessels are connected in series as viewed from the high-frequency power source side.

  ADVANTAGE OF THE INVENTION According to this invention, the lighting startability at the time of lighting a some discharge tube (light-emitting tube) with one lighting circuit can be ensured, and a non-lighting state can be prevented.

  Further, the efficiency can be improved by reducing the current flowing through the lighting circuit.

  In a preferred embodiment, the matching unit is configured by at least one capacitor or a combination of a capacitor and an inductor.

  In a preferred embodiment, there is provided an electrodeless discharge lamp lighting device in which a plurality of induction coils are arranged in one discharge vessel, and the plurality of induction coils arranged in the one discharge vessel Are connected in series as viewed from the power source side.

  In a preferred embodiment, the plurality of discharge vessels are disposed adjacent to each other, and one induction coil is disposed between the plurality of discharge vessels, and the plurality of discharge vessels are controlled to be lit by the one induction coil. The

  In a preferred embodiment, a plurality of induction coils are provided in each of the plurality of discharge vessels, and the plurality of induction coils provided in each discharge vessel are parallel to each other when viewed from the high frequency power supply side. The induction coils between the discharge vessels are connected in series.

  In a preferred embodiment, a switching unit that switches a constant of a capacitor of the matching unit in accordance with a lighting start state of the plurality of discharge containers, and a lighting detection unit that detects a lighting start state of the discharge container. The switching unit can switch the capacitor constant of the matching unit step by step based on the detection result of the lighting detection unit.

  In a preferred embodiment, the matching unit is configured to include at least one inductor, and a switching unit that switches a constant of the inductor of the matching unit in accordance with a lighting start state of the plurality of discharge vessels. A lighting detection unit that detects a lighting start state of the discharge vessel, and the switching unit can switch the inductor constant of the matching unit in a stepwise manner.

  In a preferred embodiment, a frequency control unit that changes a driving frequency of the high-frequency power source in accordance with a lighting start state of the plurality of discharge containers, and a lighting detection unit that detects a lighting start state of the discharge container. The frequency control unit can control to increase the driving frequency stepwise or continuously based on a detection result of the lighting detection unit.

  In a preferred embodiment, the lighting detection unit determines a lighting start state of the discharge container, a current flowing through a coil which is an electrical characteristic of an induction coil disposed in each discharge container, a voltage applied to both ends of the coil, or The detection can be made based on the elapsed time after the power is turned on, or the heat generation or light due to the lighting of the discharge vessel.

  With such a configuration, a plurality of arc tubes can be easily lit by a single lighting circuit, and the starting performance and efficiency in the lighting circuit can be improved by means that are easy and inexpensive to manufacture. it can.

(Embodiment 1)
FIG. 1 is a circuit diagram showing an electrodeless discharge lamp apparatus according to the first embodiment of the present invention, and FIGS. 2A to 2D are induction coils with respect to the transition of the lighting state of the arc tube in the embodiment of FIG. FIG. 6 is an equivalent circuit diagram of the arc tube portion and the arc tube portion.

  In FIG. 1, arc tubes 111 and 112 are formed of an airtight annular discharge vessel formed of a light transmissive material such as soda lime glass, borosilicate glass, or quartz. Further, the arc tube 111 and 112 have a tube outer diameter of 15 from the viewpoint of the light distribution design of the luminaire, similarly to the existing straight tube fluorescent lamp and the compact fluorescent lamp formed by folding the straight tube. Of these, T8 tube (25 mm tube) and T10 tube (32 mm tube), which are the most popular in high frequency lighting straight tube fluorescent lamps, are useful because the optical system of existing instruments can be used as they are. . Moreover, it is practical that the tube length (the total length of one discharge tube) is 150 mm to 600 mm. By arranging a plurality of tubes, a 20 W straight tube fluorescent lamp is about 600 mm and a 40 W straight tube fluorescent light. It is easy to form an instrument optical system corresponding to about 1200 mm of the lamp. In addition, the power consumption of the lamp is about the same as that of an existing facility or a straight fluorescent lamp or a compact fluorescent lamp used for outdoor illumination, and is practically 20 to 110 W. The arc tubes 111 and 112 are filled with mercury and one or more kinds of rare gases such as argon, krypton, and xenon, and the discharge vessel wall surface is coated with a phosphor (not shown). ).

  The induction coils 102 and 103 are formed of litz wire, and are wound around the toroidal ferrite cores 104 and 105 with several to several tens of turns. In addition, it is possible to design the arc tube so that the Q value (Q = ωL / Rω: angular frequency, L: inductance, R: equivalent resistance) of the combined inductor of all induction coils is 100 to 250, It is desirable from the viewpoint of lighting stability.

  The ferrite cores 104 and 105 are sandwiched so as to cover a part of the annular arc tubes 111 and 112 (Tokumaku method). At this time, the ferrite core is saturated with the magnetic flux excited by the induction coil when starting the arc tube, so that the required magnetic flux cannot be obtained and the starting performance is not impaired. In order to absorb variation in electrical characteristics due to the above, a magnetic gap may be provided by sandwiching a spacer such as a resin member in a part of the toroidal core.

  Each of the induction coil lead wires 113 and 114 has one end connected to one end of the induction coil 102 or 103 and the other end connected to the matching circuit 107. In addition, both ends of the induction coil lead wire 115 are connected to the induction coils 102 and 103. That is, induction coils 102 and 103 are connected in series by induction coil lead wires 113-115.

  The matching circuit 107 is a circuit that performs impedance matching between the induction coil and a high-frequency power source 106 (not shown) configured by a commercial power source and an inverter circuit. Usually, the matching circuit is configured by a combination of capacitors or a combination of a capacitor and an inductor in order to use a resonance phenomenon with the inductor of the induction coil. In FIG. 1, the L-shaped configuration using the two simplest capacitors is used, but the present invention is not limited to this, and a constant may be designed to resonate with the inductor of the induction coil and the target drive frequency (lighting frequency).

  The high frequency power source 106 generates a high frequency current, and induces an induced high frequency electromagnetic field in the arc tubes 111 and 112 by the high frequency current supplied from the high frequency power source 106 to generate a discharge. In consideration of switching loss in the circuit and the core material used, the high frequency power source 106 preferably has a driving frequency of 40 kHz to 3 MHz and outputs a rectangular wave or a sine wave. Since the induction coils 102 and 103 are applied with a peak-to-peak voltage of 1.5 to 2.5 kV when the arc tube is turned on, a wire with an insulating coating is used, and the induction coils 102 and 103 are used. Are connected in series with each other when viewed from the power source side.

  As described above, the Tokumak electrodeless discharge lamp is composed of a Tokumaku system with high light extraction efficiency, and the shape of the lamp distribution of two lamps that simulates a straight tube fluorescent lamp. Because it becomes. In addition, a plurality of arc tubes are arranged, as compared with the case where a long linear light source is realized with one arc tube, as described above, a short arc tube divided into a plurality is used. This is because the discharge plasma impedance can be reduced, and the discharge maintenance performance and efficiency can be improved. A linear light source can be realized by arranging a plurality of Tokumak type electrodeless arc tubes in the longitudinal direction, and a thin surface light source can be realized by arranging them in a matrix. Hereinafter, this operation principle will be described.

  2A to 2D are a partial equivalent circuit diagram of the induction coil portion and arc tube of FIG. 1 and a schematic diagram of the arc tube. FIG. 2A shows the state before the start-up lighting, FIG. 2B shows the state of E discharge immediately after the ignition is ignited in one arc tube, and FIG. 2C shows the state in which one arc tube has shifted to H discharge. FIG. 2D shows a state in which both arc tubes have shifted to H discharge. FIG. 2A to FIG. 2D illustrate how the arc tube is turned on.

  The operation of the electrodeless discharge lamp configured as described above will be described below.

  In the electrodeless discharge lamp, a high frequency power source converted from a commercial power source by an inverter is used to generate a large voltage and current by utilizing a resonance phenomenon between the capacitor of the matching circuit 202 shown in FIG. 2A and the induction coils 203 and 204. 203 and 204. After the power is turned on, discharge arcs are generated by the induction high-frequency electromagnetic field in order from the plurality of arc tubes 205 and 206 that are most easily started (the arc tube 205 in the example in the figure). FIG. 2B shows an equivalent circuit model of capacitively coupled plasma (E discharge) formed in the arc tube 205 by the generation of a seed flame.

In the E discharge, as shown in FIG. 2B, C _pl of the plasma capacitance component 207 and R _{pl of the} resistance component 208 are connected in parallel to the induction coil 203, and a path through which a new current flows is created ( Strictly speaking, there is also a capacitance component due to the discharge vessel being a dielectric). For this reason, the current flowing through L _{1 of the} induction coil 203 is divided into two, the induction coil side and the plasma side, and the induced voltage applied to both ends of the induction coil L ₁ is lowered accordingly. That is, the impedance is lowered.

In addition, in the other arc tube 206 in which no seed fire is generated, there is no current path other than L _{2 of the} induction coil 204, and the induction coil L ₁ and the induction coil L ₂ are connected in series. , the induced voltage across the induction coil L ₂ is not reduced. If if parallel connection, when compared with the drops induced voltage of the induction coil L ₂ is dragged by the reduction of the induced voltage of the induction coil L1, alone it an arc tube 206 which discharge start is delayed for turning on the starting Since a sufficient voltage (electric field) can be applied to this, it can be easily analogized that it works advantageously.

  Further, in FIG. 2C, the equivalent of a mode jump from the E discharge to the inductively coupled plasma (H discharge) having a very high plasma density and a high luminous efficiency in the arc tube 205 that started the discharge earlier. A circuit model is shown.

  Although there are various theories regarding the mechanism and requirements for shifting from E discharge to H discharge, the actual situation is not clear. Generally, the plasma filled in the arc tube forms a donut-shaped loop, and the plasma plays a role of the secondary coil of the transformer only when a loop-shaped current flows through the plasma. And is thought to lead to inductive coupling.

In the case of FIG. 2C, the secondary side of the transformer is composed of L _p1 which is an inductance component 309 of plasma and a resistance component R _p1, and the induction coil 203 is the primary side and the plasma inductor L _p1 is the loop coil of one turn. The arc tube is H-discharged by magnetic coupling (coupling). The plasma inductor L _p1 is a combination of the shape of the plasma and the inertia of the movement of electrons in the plasma. Usually, the arc tube lighting frequency is several MHz or less, compared with the plasma frequency (several tens of GHz). Since the movement of electrons can sufficiently follow the lighting frequency, it is negligible. For this reason, it may be considered that it is almost due to the shape of the plasma.

Also, C _p2 and R _p1 in FIG. 2C are equivalent circuit models representing a capacitance component 307 and a resistance component 308, respectively, of capacitively coupled plasma (E discharge) generated in the arc tube 206 in which the discharge of the discharge was generated late. is there. FIG. 2D shows a state when this mode jumps and shifts to H discharge which is inductively coupled plasma. L _p2 and R _p2 are an inductance component 311 and a resistance component 312 of the plasma, respectively. .

As is generally well known, when H discharge occurs, the voltage applied to both ends of the induction coil is significantly about 1/3 to 1/5 before the start of discharge and the state of E discharge. descend. This is due to the effect of mutual inductance between a primary coil (corresponding to an induction coil) and a secondary coil (corresponding to a discharge current loop formed by plasma and regarded as a one-turn coil) described later. It is. Due to this mutual inductance, the inductance component of the induction coil apparently decreases, so that the voltage induced at both ends of L ₁ of the induction coil 203 shown in FIG. 2C is greatly reduced.

In the present embodiment, since L ₁ of induction coil 203 and L _{2 of} induction coil 204 are connected in series, the charge (partial pressure) of the voltages of L ₁ and L ₂ is L in accordance with Ohm's law. ₁ voltage is than allowed to increase the voltage of the only L ₂ amount corresponding to the reduction. As a result, in the arc tube 206 whose discharge start is delayed, it is possible to obtain a sufficient voltage and induction electric field sufficient to cause a discharge mode jump from the discharge start (ignition) to E discharge and H discharge. Lighting start is easy and reliable.

In addition, when L ₁ and L ₂ are connected in parallel, the voltage of the induction coil L ₂ is lowered by being dragged by the voltage drop of the induction coil L ₁ on the arc tube side that has shifted to H discharge _first . In the arc tube with a delayed start of discharge, a voltage and an induced electric field sufficient for mode jump from L ₂ to E discharge and H discharge cannot be obtained. Needless to say.

  Next, the influence of mutual inductance between the induction coil and plasma when this H discharge is reached will be described.

FIG. 3A shows a general coupling circuit of the transformer, and FIG. 3B shows an equivalent circuit thereof. 3A and FIG. 3B, L ₁ is a primary coil 401, the electrodeless discharge lamp device correspond to the induction coil. L ₂ is a secondary coil 402, which corresponds to the plasma inductance component (one turn coil) formed in the arc tube by inductively coupled discharge in the electrodeless discharge lamp apparatus, and mainly the shape of the plasma (plasma density is also Including). M is a mutual inductance (M includes a sign) acting between the primary side coil 401 and the secondary side coil 402, and by applying a voltage of V _{1 to} the primary side, The state of inducing the voltage of V ₂ is shown. As apparent from FIGS. 3A and 3B, the voltage V ₁ of the primary coil 401 is affected by the current I ₂ flowing through the secondary coil 402. The voltage V ₂ of the secondary coil is affected by the current I ₁ of the primary coil.

  The relationship between the voltage and current of such a coupling circuit is expressed by the following Equation 1 when expressed using complex voltage and complex current, respectively.

V ₁ = jωL ₁ * I ₁ + jωM * I ₂
V ₂ = jωL ₂ * I ₂ + jωM * I ₁
(V ₁ , V ₂ , I ₁ , and I ₂ are all complex voltage and current, j is an imaginary number, and ω is an angular frequency.) [Equation 1]

  At this time, a code is included in M (in the case of electrodeless discharge, the voltage decreases when the H discharge is reached, so here M <0). Further, M is expressed as in Equation 2 below, and the coupling coefficient k takes a value of −1 ≦ k ≦ 1, and the closer to | k |, the higher the coupling.

M = k√ (L ₁ * L ₂ ) (Equation 2)

Thus, the primary-side voltage V ₁ decreases in proportion to the magnitude of the mutual inductance M, and the magnitude of M is proportional to the square root of L ₂ (corresponding to an inductance component of plasma in an electrodeless discharge lamp). Since it is proportional to the coupling coefficient k, the electrodeless discharge lamp with a high coupling rate, that is, the above-described Tokumak method or the highly efficient electrodeless discharge lamp with a high plasma density is induced by shifting to H discharge. That is, the degree of voltage drop of the coil increases. Further, the LC resonance frequency by the capacitor of the matching circuit and the inductor of the induction coil is described as the following Equation 3.

F = 1 / (2π√ (L * C)) [Equation 3]
(F is the resonance frequency, F = ω / 2π)

  In Equation 3, L is a combined inductance of a plurality of induction coils, and C is a combined capacitance of all capacitors included in the matching circuit.

  After this transition to H discharge, the inductance component of the plasma, which depends on the shape of the plasma and the input power (again, the inductance is overwhelmingly large due to the large current loop in the Tokumaku method), is added from L to L ′. The resonance frequency changes from F to F ′. In other words, the transition of the resonance frequency increases as the plasma inductance component increases. Conversely, the greater the combined inductance of the induction coil, the smaller the fluctuation due to the plasma inductance component is, compared to the inductance of the induction coil, so the transition of the resonance frequency is reduced. In other words, since the combined inductance of the induction coils is larger in the series connection of the induction coils, the deviation from the resonance frequency before and after the transition to the H discharge is smaller.

  From the above, the characteristics obtained by connecting the induction coils arranged in different looped arc tubes in series as in the electrodeless discharge lamp device of the present invention are described below.

  First of all, it is possible to perform the lighting start well and reliably. In other words, when multiple lamps are lit, the induction coil disposed in the arc tube whose lighting start has been delayed due to the decrease in the induced voltage of the induction coil disposed in the arc tube that has started discharging earlier. The induced voltage increases. This is because an induction electric field sufficient to shift to H discharge can be obtained.

  Second, it is possible to achieve both lighting startability and efficiency. That is, since a plurality of induction coils are connected in series, the combined inductance is larger than that in parallel connection (the combined inductance is smaller in parallel connection). For this reason, the influence of fluctuation of the inductance component of the plasma generated by mode jumping to the H discharge plasma is relatively reduced. As a result, the difference between the resonance frequency before the start of discharge and the resonance frequency after the transition to H discharge is small, and the degree of decrease in the power factor (impedance matching) is small compared to the case of parallel connection. If the deviation of the resonance frequency is large before and after the start of lighting, the drive frequency of the inverter must be designed at a compromise between the resonance point before start and the resonance point during steady lighting (after transition to H discharge). Needless to say, it is difficult to achieve both startability and efficiency.

  Third, by connecting the induction coils in series, the total amount of current that flows in the lighting circuit (total amount of current) is significantly smaller than that in parallel connection, reducing the power consumption of the circuit elements in the high-frequency power supply section. It can be kept small. For this reason, the loss in the lighting circuit can be reduced, and at the same time, the electromagnetic noise (particularly the radiation magnetic field) radiated from the lighting circuit can be reduced.

  Among the forms of electrodeless discharge lamps, discharge lamps having a relatively high electromagnetic induction coupling ratio between the primary side induction coil and the secondary side plasma coil and being easy to obtain efficiency (for example, closed loop light emission) The superiority of the above two features becomes more pronounced as the tube-shaped electrodeless discharge lamp (Tumaku type electrodeless discharge lamp) and the discharge lamp with higher input power (high plasma density) for high output.

  Thereby, before and after the transition of the H discharge, it is possible to light a plurality of Tokumaku type electrodeless discharge lamps having a large impedance fluctuation of the load (the arc tube and the excitation coil). In addition, it is possible to turn on a plurality of Tokumaku type electrodeless discharge lamps that are efficient and have convenience that can be applied to both line light sources and surface light sources depending on how light sources are arranged, and lighting design is easy.

  In the present embodiment, an example in which two arc tubes are arranged is shown, but the same effect can be obtained when there are three or more arc tubes.

  In addition, although the arc tube has been shown with a katakana “b” shape, it is not limited to this, but the shape of the discharge plasma, such as the alphabet “O” type (annular) or “H” type. The discharge vessel may be formed in a loop shape.

  The configuration of the matching circuit 107 is the simplest L-type example in which two capacitors are connected in series and parallel in the present embodiment. However, the configuration is not limited to this configuration. A type circuit configuration may be used. Furthermore, a composite combination of a capacitor and an inductor may be used. Further, although the matching circuit 107 of the present embodiment has a single resonance system configuration, a resonance system (matching circuit) may be provided for each induction coil arranged in each arc tube.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to FIG.

  In FIG. 4, an electrodeless discharge apparatus includes a high-frequency power source 501, a matching circuit 502 for resonating with an induction coil, two arc tubes 503 and 504, and induction coils 505 to 505 arranged in the respective arc tubes. 508.

  The arc tube 503 is provided with induction coils 505 and 507, and the arc tube 504 is provided with induction coils 506 and 508. All the induction coils 505 to 508 are connected in series, and one end of each of the induction coils 505 and 506 is connected to the matching circuit 502. When arranging a plurality of induction coils on the same arc tube, it is necessary to pay attention to the installation direction of the coils for the connection between the induction coils, and the direction of the induction electric field generated in the arc tube by the induction coil is They must be aligned in the same direction along the loop in the tube shape (matching phase). This is because if the direction of the induced electric field is not the same circumferential direction along the loop in the tube shape, the generated induced electric fields cancel each other, a discharge current loop is not formed, and it is not possible to shift to H discharge.

  In order to shift to the H discharge of steady lighting, the arc tubes 503 and 504 must be filled with plasma by E discharge to form a loop current path in the tube. When the density of the plasma formed in this loop shape increases and a discharge current flows along this loop, the current path flows only in a part of the arc tube adjacent to the induction coil formed by E discharge, The current path that makes a loop around the arc tube shifts to the main body, that is, this is the transition operation to H discharge.

  As a result of an experimental study on the mechanism of the transition of the discharge mode (E discharge to H discharge) and image analysis by high-speed camera photography of the discharge light emitting part (plasma) in the transient state at the start of lighting, the following conclusions have been obtained. I came to find. That is, since the E discharge is a discharge of only a part of the arc tube adjacent to the induction coil, this is further diffused in the tube by increasing the density of the plasma, and since the plasma is a conductor, it is generated in the plasma. It is experimentally demonstrated that the process of moving charged particles in plasma in an in-tube loop shape (that is, forming a discharge current loop) by an induction electric field generated by an induction coil without delay is easy to shift to H discharge. I found it. For this reason, in order to shift from the E discharge to the H discharge, a part of the induced electric field in the arc tube is not partially extremely strong, but forms a moderately strong induced electric field that is wide throughout the tube. It has become clear that it plays a major role in the transition of H discharge.

  The strength of the induced electric field decreases as the distance from the induction coil increases in inverse proportion to the square of the distance according to Bio-Savart's law. Therefore, how to increase the induction electric field at the position farthest from the induction coil in the tube is an important requirement for good startability (mode jump to H discharge). The distance from the induction coil to the portion inside the arc tube that is farthest from the induction coil, that is, the end 108 of the arc tube on the side facing the induction coil in the example of the induction coil arrangement in FIG. In the example of arrangement of the induction coil in FIG. 4, when compared with the vicinity of the arc tube center 509 having the same distance from both opposing induction coils, the case of FIG. 4 is about half (1/2) that of FIG. It becomes the distance. FIG. 4 shows a configuration in which one induction coil is divided into two induction coils. For example, when the induction coil is equally divided, the induced voltage generated at both ends of the induction coil is halved, and the induced electric field inside the arc tube in the vicinity of the induction coil is also halved (because there is a little distance from the coil). Slightly smaller than 1/2). Since the distance is proportional to the inverse square of the distance, the position 509 farthest from the induction coil inside the arc tube has a distance ½ that of the position 108. It becomes. That is, as a result, when the performance factor of the induction coil and the distance factor are multiplied, the induced electric field at the position 509 is twice the induced electric field at the position 108. Further, since the electromagnetic phenomenon is superposed, when the number of induction coils is two as shown in FIG. 4, the induction electric field strength is four times the total. That is, since the induction electric field in the farthest part from the induction coil, which has become a bottleneck for shifting to H discharge, can be effectively increased, lighting startability (mode jump from E discharge to H discharge) Can be significantly improved. Therefore, the startability is further improved by dividing a plurality of induction coils and arranging them on the path of the H discharge current loop. In the configuration shown in FIG. 4, two induction coils are arranged opposite to each other on one arc tube, but the same effect can be obtained even if divided into three or more. The same effect can be obtained even when the arrangement intervals are uneven.

(Embodiment 3)
A third embodiment of the present invention will be described with reference to FIG.

  Fig.5 (a) is a side view of an electrodeless discharge lamp apparatus, FIG.5 (b) is a top view. In the configuration of FIG. 5, among a plurality of induction coils arranged on the same arc tube, one induction coil 607 is arranged adjacent to each other by two arc tubes 603 and 604 adjacent (integrated). It has become the composition that is. That is, as shown in FIG. 5, an induction coil 607 is wound between two arc tubes 603 and 604 held by one ferrite core 609. In the arc tube 603, a ferrite core 608 around which a dielectric coil 605 is wound is disposed at a position facing the ferrite core 609. In the arc tube 604, a ferrite core 610 around which a dielectric coil 606 is wound is disposed at a position facing the ferrite core 609. The dielectric coils 605, 607, and 606 are connected in series, and both ends are connected to the matching circuit 602.

  By connecting the induction coils 605, 606, and 607 in series as shown in FIG. 5, the direction of the induction electric field generated in the arc tube by the induction coil is aligned in the same direction along the loop of the arc tubes 603 and 604. The phase can be adjusted.

  In the electrodeless discharge lamp device having such a configuration, the principle of lighting is the same as that of the second embodiment (see FIG. 4), but the number of parts can be reduced compared to the configuration of FIG. can do. In addition, the apparatus can be made compact.

  In the present embodiment, the two arc tubes 603 and 604 are described as an example, but may be three or more. In that case, the same effect as described above can be obtained by holding a plurality of arc tubes connected in a daisy chain with a ferrite core having a configuration capable of holding two arc tubes such as the ferrite core 609.

(Embodiment 4)
A fourth embodiment of the present invention will be described with reference to FIG.

  In FIG. 6, the high frequency power source 701 is connected to the induction coils 705 to 708 via the matching circuit 702. The induction coil 705 and the induction coil 707 disposed in the arc tube 703 are connected in parallel, and the directions of the induction electric fields generated by the induction coils 705 and 707 are matched. In addition, the induction coil 706 and the induction coil 708 disposed in the arc tube 704 are connected in parallel. Connections between the induction coils arranged across the two arc tubes 703 and 704 are connected in series as viewed from the high-frequency power source 701 side.

  With the configuration shown in FIG. 6, when the induced voltage applied to both ends of the induction coil disposed in the arc tube previously shifted to the H discharge decreases, the other arc tube (the light emission whose start of discharge is delayed). Since the voltage induced in the induction coil disposed in the tube is a series connection as viewed from the power supply side, the voltage rises due to the partial pressure relationship. In other words, it has the original characteristic of facilitating from the start of discharge to transition to H discharge.

  The reason why a plurality of induction coils are arranged on the same arc tube is to increase the strength of the induction electric field and to distribute the initial plasma during E discharge, for the same reason as described in the second embodiment of the present invention. It is to spread.

  In addition, by connecting the induction coils arranged on the same arc tube in parallel, the voltage of the induction coil 705 and the induction coil 707 or the voltage of the induction coil 706 and the induction coil 708, the inside of the arc tube generated by the induction coil Since the induced electric field is symmetrical, the influence on the plasma during discharge becomes equal on both sides. As a result, the emission luminance on the same arc tube can be uniformed and the efficiency can be increased.

  As described above, according to the present embodiment, the change in the resonance frequency before the start of lighting of the arc tube and after the transition to the H discharge is small as compared with the case where the induction coil is connected in parallel when viewed from the power source side. As described above, it is completed. However, in this case as well, the power efficiency of the load side input of the resonance system (including the matching circuit) decreases due to the difference between the drive frequency of the inverter and the resonance frequency, and the circuit efficiency slightly decreases due to the increase in current and voltage. Is inevitable. An embodiment of the present invention that improves the deviation between the inverter drive frequency and the resonance frequency before and after lighting and suppresses the decrease in efficiency will be described below with reference to FIGS. 7A to 8B.

  FIG. 7A shows an example of the matching circuit unit according to the embodiment of the present invention. The input terminal 801 to the matching circuit unit is connected to the output terminal 806 to the induction coil and arc tube side through the matching circuit 802. The matching circuit 802 is basically composed of a capacitor 803 and a capacitor 804, and a variable capacitor 805 is connected in parallel to the capacitor 804.

  In FIG. 7A, when the discharge mode of the arc tube shifts to H discharge, the combined inductance on the load side of the induction coil and the inductance component of the plasma decreases due to the inductance component of the discharge plasma. Therefore, as shown in the mathematical formula 3, the resonance frequency shifts higher as the inductance component becomes smaller. In order to make this resonance frequency and the drive frequency of the inverter coincide before and after the H discharge, the decrease in the inductance component is compensated by increasing the capacitor component in the matching circuit section, and the resonance frequency in the resonance circuit is increased. Can be constant. That is, the variable capacitor 805 included in the matching circuit unit 802 is for performing this correction, and the resonance frequency can be matched with the drive frequency of the inverter by the variable capacitor 805 before and after transition to H discharge. The capacitance (constant) of the capacitor to be switched stepwise may be designed in advance according to the change in inductance component due to the plasma of the arc tube to be lit.

A more specific configuration of the variable capacitor 805 is shown in FIG. 7B. As shown in FIG. 7B, the variable capacitor 805 in FIG. 7A can be realized in place of the variable capacitor unit 807 in FIG. 7B. The variable capacitor unit 807 connects capacitors C ₁ and C ₂ having different capacities in parallel, the capacitor C ₁ is ON / OFF controlled by the switch SW1, and the capacitor C ₂ is ON / OFF controlled by the switch SW2.

  When each arc tube is turned on in sequence, the inductance component formed by the discharge plasma is determined by the arc tube shape (plasma shape) and input power (rated power consumption). If it is decided, it will be decided by itself. Therefore, each time the arc tube shifts to H discharge, the lighting state is detected, the switches SW1 and SW2 included in the variable capacitor 807 are sequentially switched, the capacitance of the variable capacitor 807 is determined, and the matching circuit unit 802 Adjust the resonance frequency to the drive frequency of the inverter.

  When the arc tube is switched to H discharge, the voltage and current of the induction coil disposed in the arc tube are greatly reduced. This may be detected, or the arc tube is switched to H discharge. Then, the light output increases extremely, and this may be detected by a light detection element such as a photodiode. Further, it may be configured by a timer element for detecting the amount of heat (temperature) of the arc tube or the induction coil or switching the circuit when a certain time elapses in advance.

  The switching element for switching includes a relay circuit that switches using the detected signal as a trigger, a switching thermistor represented by PTC (resistance increases as temperature rises) and NTC (resistance decreases as temperature rises). You may comprise by an element.

  Further, as shown in FIG. 7A, as the simplest example, a variable capacitor is connected in parallel to one capacitor 804 of an L-type matching circuit in which capacitors are connected in series and parallel. Alternatively, the capacitor component of the matching circuit portion may be made variable by being connected in series or in parallel to the capacitor 804. However, in the case of inserting in series and in the case of inserting in parallel, the switching state of the switch before and after the transition to the H discharge is reversed, and in either case, switching must be performed so as to increase the capacitor component in the matching circuit section. Don't be.

Next, FIG. 8A shows a configuration in which the role of the variable capacitor 805 in FIG. 7A is substituted with a variable inductor 903. This arrangement, the load side of the inductance component that changes before and after H discharge transition of the arc tube is intended to supplement a variable inductor 903, including the matching circuit is serially connected to the capacitor C _2. As a result, the drive frequency of the inverter can be matched with the resonance frequency of the resonance circuit constituted by the matching circuit, the induction coil, and the arc tube (plasma).

FIG. 8B is a more specific example of the variable inductor 903 of FIG. 8A, and the configuration of the lighting state detection means for switching and the configuration of the selector switch is the same as the configuration of FIG. 7B. The variable inductor 905 includes switches SW3 to SW6 and inductors l ₁ and l ₂ having different inductances. Based on the detection result of the lighting state detection means, SW3 to SW6 are switched, the inductance in the variable inductor 905 is determined, and the resonance frequency of the matching circuit unit is switched. Specifically, a _first state in which the switches SW3 and SW6 are turned on to make the inductor l ₁ conductive, and a second state in which the switches SW4 and SW5 are turned on to make the inductor l ₂ conductive. have.

  Further, the above configuration is a method of adjusting the resonance frequency on the load side including the matching circuit, the induction coil, and the arc tube, but not limited to such a configuration, by means for detecting the lighting state of the arc tube, A function of feeding back to the resonance circuit that determines the drive frequency of the inverter circuit (high frequency power supply) may be provided, and the drive frequency of the inverter circuit may be made to follow the change in the resonance frequency on the load side. In that case, it is preferable to provide a frequency control unit that controls the drive frequency to increase stepwise or continuously.

  As a result, the resonance frequency of the resonance system composed of the matching circuit, induction coil, and plasma inductance component and the inverter drive frequency can be adjusted in time before and after the start of lighting. Lighting can be started easily without lowering the oscillation voltage, oscillation current, and power factor in the circuit, and the power factor in the resonance circuit will not be lowered even after transition to the H discharge of steady lighting. Therefore, the efficiency of the lighting circuit can be increased.

  In the embodiment of the present invention, the case of two arc tubes as multi-lamp lighting is shown. However, the present invention is not limited to this, and the same effect can be obtained even if the number and position of induction coils are different. Obtainable.

  Further, in the present embodiment, the induction coil is wound around the toroidal core. However, the present invention is not limited to this, and as shown in FIGS. 9A to 9F, an induction equipped with a toroidal core is mounted. A configuration in which a part of the coil 1002 is arranged along the wall surface of the loop-shaped arc tube 1001 may be used. FIG. 9A shows an example in which the induction coil 1002 is arranged at the end of the arc tube 1001 far from the matching circuit. FIG. 9B is an example in which induction coils 1003 and 1004 are arranged at opposite ends of the arc tube 1001, and the induction coils 1003 and 1004 are connected in series. FIG. 9C is an example in which induction coils 1003 and 1004 are connected in parallel with the same arrangement as in FIG. 9B. FIG. 9D shows an example in which the induction coil 1010 is wound in a loop shape along the arc tube 1001 and the end thereof is fixed by a magnet 1007. FIG. 9E shows an example in which the induction coil 1010 is fixed by magnets 1007 and 1008 at both ends of the arc tube 1001. FIG. 9F shows an example in which the coil is wound in a loop shape along the arc tube 1001, and the induction coil 1010 is not fixed by a magnetic core.

  The specification of the discharge vessel is not limited to the above embodiment, and may be a single gas or a mixed gas of not only a mixed gas of argon and krypton but also other rare gases (neon, argon, krypton, xenon, etc.). Further, other metal vapor may be used instead of mercury, and the same effect can be obtained even when only a rare gas is used.

  Since the electrodeless discharge lamp of the present invention can improve the discharge startability of the lamp by means that are easy to manufacture and low-cost, it is useful for general facilities, indoor / outdoor lighting, and the like.

A circuit diagram showing an outline of an electrodeless discharge lamp device in Embodiment 1. Schematic diagram of equivalent circuit of induction coil portion and arc tube in embodiment 1 (before starting lighting) Schematic diagram of equivalent circuit of induction coil portion and arc tube in embodiment 1 (state of E discharge immediately after ignition of first arc tube in one arc tube) Schematic diagram of an equivalent circuit of the induction coil portion and arc tube in the first embodiment (a state where one arc tube has shifted to H discharge) Schematic diagram of equivalent circuit of induction coil portion and arc tube in embodiment 1 (both arc tubes are in H-discharge state) Schematic diagram showing the configuration of an inductive coupling circuit Equivalent circuit showing configuration of inductive coupling circuit The circuit diagram which shows the outline of the electrodeless discharge lamp apparatus in Embodiment 2 (A) Side view of arc tube of electrodeless discharge lamp apparatus according to embodiment 3 (b) Plan view of electrodeless discharge lamp apparatus according to embodiment 3 The circuit diagram which shows the outline of the electrodeless discharge lamp apparatus in Embodiment 3 The circuit diagram which shows the structure of the matching circuit which has the function which switches the capacitor constant in embodiment The circuit diagram which shows the structure of the matching circuit which has the function which switches the capacitor constant in embodiment The circuit diagram which shows the structure of the matching circuit which has a function which switches the inductor constant in embodiment The circuit diagram which shows the structure of the matching circuit which has a function which switches the inductor constant in embodiment Schematic diagram showing an example in which a part of the induction coil disposed on the closed loop arc tube is wound along the wall surface of the arc tube Schematic diagram showing an example of connecting two induction coils in series Schematic diagram showing an example of connecting two induction coils in each arc tube in parallel Schematic diagram showing an example of winding an induction coil along the wall of the arc tube Schematic diagram showing an example with two magnetic cores Schematic diagram showing an example of using no magnetic core (air core) Schematic diagram showing the outline of a conventional electrode discharge discharge lamp device

Explanation of symbols

102, 103 Inductive coil 104, 105 Ferrite core 106 High frequency power supply 107 Matching circuit section 111, 112 Discharge vessel (arc tube)
501 High-frequency power supply 502 Matching circuit section 503, 504 Arc tube 505, 506, 507, 508 Induction coil

Claims (10)

A plurality of discharge vessels, which are made of a light-transmitting material and in which an enclosure made of at least a metal vapor and a rare gas is enclosed;
An induction coil disposed in each discharge vessel so as to induce an induction high-frequency electromagnetic field in a discharge space inside the discharge vessel and discharge the inclusion;
A high frequency power source for supplying high frequency power to the induction coil;
A matching unit including a resonance circuit that performs impedance matching between the induction coil and the high-frequency power source, and an electrodeless discharge lamp lighting device comprising:
The induction coil is an electrodeless discharge lamp device in which induction coils arranged in different discharge vessels are connected in series as viewed from the high frequency power supply side.   The electrodeless discharge lamp device according to claim 1, wherein the matching unit includes at least one capacitor or a combination of a capacitor and an inductor. An electrodeless discharge lamp lighting device in which a plurality of induction coils are arranged in one discharge vessel,
The electrodeless discharge lamp device according to claim 1, wherein a plurality of induction coils arranged in the one discharge vessel are connected in series as viewed from the power source side. The plurality of discharge vessels are disposed adjacent to each other;
One induction coil is arranged between the plurality of discharge vessels,
The electrodeless discharge lamp device according to claim 1, wherein lighting of the plurality of discharge vessels is controlled by the one induction coil. A plurality of induction coils are respectively disposed in the plurality of discharge vessels,
In each discharge vessel, a plurality of arranged induction coils are connected in parallel with each other when viewed from the high-frequency power source side,
The electrodeless discharge lamp device according to claim 1, wherein the induction coils between the discharge vessels are connected in series. In accordance with the lighting start-up state of the plurality of discharge containers, a switching unit that switches the constant of the capacitor of the matching unit,
A lighting detection unit for detecting a lighting start state of the discharge vessel,
The electrodeless discharge lamp device according to any one of claims 1 to 5, wherein the switching unit switches a constant of the capacitor of the matching unit in a stepwise manner based on a detection result of the lighting detection unit. The matching portion includes at least one inductor.
In accordance with the lighting start state of the plurality of discharge containers, a switching unit that switches the constant of the inductor of the matching unit,
A lighting detection unit for detecting a lighting start state of the discharge vessel,
The electrodeless discharge lamp device according to claim 1, wherein the switching unit switches the constant of the inductor of the matching unit in a stepwise manner. In accordance with the lighting start state of the plurality of discharge containers, a frequency control unit that changes the driving frequency of the high-frequency power source,
A lighting detection unit for detecting a lighting start state of the discharge vessel,
The electrodeless discharge lamp device according to any one of claims 1 to 5, wherein the frequency control unit controls the drive frequency to increase stepwise or continuously based on a detection result of the lighting detection unit. The lighting detection unit is a lighting start state of the discharge vessel,
Based on the current flowing through the coil, which is the electrical characteristic of the induction coil disposed in each discharge vessel, the voltage applied to both ends of the coil, the elapsed time after turning on the power, or the heat generation and light due to lighting of the discharge vessel The electrodeless discharge lamp device according to any one of claims 6 to 8, which is detected. A lighting fixture using the electrical assembly according to any one of claims 1 to 9.

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