JP2007250285A - Discharge lamp lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize a lighting operation of a discharge lamp, in a discharge lamp lighting device equipped with a long secondary wiring. <P>SOLUTION: In the discharge lamp lighting device provided with an alternating-current power source V, a ballast 1 connected with the power source V and equipped with a coil ML and a resonant capacitor CO, a discharge lamp L lighting up or flashing with power supplied from the ballast 1, and secondary wirings 11 to 14 consisting of at least two wires electrically connecting the ballast 1 and the discharge lamp L, a capacitance of the resonant capacitor is to be 1,000 [pF] or more, an operating frequency of the ballast 1, 10 to 60 [kHz], and an inter-wiring capacitance in the secondary wirings 11 to 14, 2,000[pF] or less. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device including a fluorescent lamp or the like.

In many cases, a discharge lamp such as a fluorescent lamp and a ballast are integrated as a lighting device. Such a ballast is described in, for example, Patent Document 1 because it has advantages such as high efficiency and power saving, flickering of a discharge lamp, reduction of noise and weight of the ballast, and the like. Many neutral point type ground boost type inverters are used. Lighting devices equipped with such high-frequency ballasts are widely used in the market, and are often used in lighting devices such as showcases and show windows in stores. Such a lighting device is often installed so that the display space for the product is as large as possible so that the main body of the lighting device cannot be seen from the outside. For example, a product display shelf board is dug, a lamp, a socket, etc. are embedded, and a ballast is arranged in a ceiling inspection opening etc., an exhibition space can be expanded and it can illuminate with the minimum member.
Japanese Patent No. 2869397

  As described above, when the lamp and socket are arranged on the exhibition space side, and the ballast is arranged away from the lamp and socket at the ceiling inspection port or the like, the secondary wiring connecting the lamp and the ballast is 10 [m]. The length of the degree was necessary. However, many lighting devices equipped with high-frequency ballasts are often designed to operate normally when the secondary wiring is used at 3 [m] or less, and the secondary wiring length is 10 [m]. When used as such, operations such as temperature rise of the ballast, flickering of the discharge lamp, malfunction of the protection circuit, etc. have become unstable.

  Moreover, in order to show the secondary wiring clearly, a parallel cord or a flat cabtyre cord is generally used. However, the more bundled, the greater the inter-wiring capacitance of the secondary wiring. This also caused the unstable operation of the lighting device.

  The present invention has been made in view of the above circumstances, and provides a discharge lamp lighting device capable of realizing a stable operation even if the capacitance between wirings of the secondary wiring increases due to a long secondary wiring or the like. Objective.

  In order to solve the above problems, a discharge lamp lighting device of the present invention is lit by an AC power source, a ballast connected to the AC power source and having a resonance coil and a resonance capacitor, and power supplied from the ballast. Or a discharge lamp lighting device comprising: a flashing discharge lamp; and a secondary wiring composed of at least two wirings for electrically connecting the ballast and the discharge lamp. It is not less than [pF], the operation frequency of the ballast is 10 to 60 [kHz], and the inter-wiring capacitance in the secondary wiring is not more than 2000 [pF].

  The capacitance of the resonant capacitor is 1000 [pF] or more, but it is desirable that the capacitance is such that the inter-wiring capacitance in the secondary wiring can be ignored and the inductivity of the ballast switching mode can be maintained. Furthermore, the operating frequency of the ballast is 10 to 60 [kHz]. However, since the transmission / reception frequency of the remote controller used for electrical appliances is 33 to 40 [kHz], the operating frequency excluding this frequency band is used. It is desirable that

  In addition, the discharge lamp lighting device of the present invention can provide stable operation without being affected by the capacitance between wirings, particularly when the secondary wiring length is about 10 [m].

  Furthermore, the discharge lamp lighting device of the present invention includes an AC power supply, a ballast connected to the AC power supply and having a resonance coil and a resonance capacitor, and a discharge lamp that is turned on or blinks by electric power supplied from the ballast. The operating frequency of the ballast is 10 to 60 [kHz], the capacity of the resonant capacitor is 1000 [pF] or more, and the resonant capacitor is arranged in the vicinity of the discharge lamp. And a secondary wiring composed of at least two wirings for electrically connecting the discharge lamp, the resonant capacitor, and the resonant coil. The capacitance between the secondary wirings is 2000 [pF ] It is characterized by the following.

  Here, “the resonance capacitor is disposed in the vicinity of the discharge lamp” means, for example, that a resonance capacitor is disposed around a socket or the like constituting the discharge lamp.

  By setting the capacitance of the resonant capacitor used in the ballast to 1000 [pF] or more, the operating frequency of the ballast to 10 to 60 [kHz], and the interwiring capacitance in the secondary wiring to 2000 [pF] or less, for example, Even if the secondary wiring is about 10 [m], it is possible to prevent flickering, abnormal operation, etc. of the discharge lamp and to realize stable operation. Moreover, the temperature rise of the circuit components which comprise a ballast can be suppressed, switching noise can be reduced, and operation stability equivalent to a high frequency ballast can be realized.

  Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment>
1 to 5 are examples of circuit diagrams of the discharge lamp lighting device according to the first embodiment. FIG. 1 shows a discharge lamp lighting device comprising an AC power source V, an inverter circuit 90, and a standard ballast 1 having a resonance capacitor C0 and a coil ML, and performing constant current preheating of the filament of the discharge lamp L by the capacitor C0. FIG. 2 is a circuit diagram of a discharge lamp lighting device including a ballast 2 having a filament transformer FT for performing filament preheating of the discharge lamp L in addition to the resonant capacitor C0 and the coil ML. FIG. 3 is a circuit diagram of a discharge lamp lighting device including a ballast 3 having a transformer MT having both a resonance capacitor C0 and a transformer for lighting a discharge lamp and a winding for filament preheating. The capacitors CD, C1 and C2 in FIGS. 1 to 3 are for facilitating detection of abnormal operation of the discharge lamp and for preventing an excessive current from flowing through the low impedance filament winding due to an external short circuit or the like.

  The ballast 1 is connected to the discharge lamp L via the secondary wires 11 to 14, the ballast 2 is connected to the discharge lamp L via the secondary wires 21 to 24, and the ballast 3 is connected to the secondary wire 31. To the discharge lamp L via .about.34. That is, each ballast and the discharge lamp L are connected through four secondary wires. Each secondary wiring is constituted by a parallel line or a flat cabtyre cord, and is bundled two by two. When each secondary wiring length is 10 [m] or more, the total capacity between the bundled secondary wirings (for example, the wiring capacity between the secondary wiring 11 and the secondary wiring 12) is 2000 [pF] or less. By setting the resonant capacitor C0 to 1000 [pF] or more and the operating frequency of the ballasts 1, 2 and 3 to 10 to 60 [kHz], the length of the secondary wiring connecting each ballast and the discharge lamp Even when the discharge lamp is long, the lighting operation of the discharge lamp can be kept stable. The capacity of the resonance capacitor C0 is preferably a capacity that can ignore the inter-wiring capacity of the secondary wiring.

  1 to 3, the elements that determine the operating frequency of the ballasts 1, 2, and 3 are the resonant capacitor C0 and the coil ML or the transformer MT. When the capacity of the resonant capacitor C0 is increased, the high-frequency switching mode is capacitive. Therefore, it becomes extremely lossy switching and lacks practicality. Accordingly, it is preferable to increase the reactance of the coil ML and the transformer MT as the capacity of the resonance capacitor C0 increases, and maintain the high frequency switching mode in the inductive region.

  In order to reduce the size of the ballasts 1, 2 and 3 as much as possible, for example, the transformer MT has a volume about 2.6 times that used in a normal ballast, and the case for housing the ballast is Compared to those normally used, the length is the same, the width is 1.1 times, and the thickness is 1.5 times. In addition, in order to maintain inductivity without increasing the size of the ballast as much as possible, further stable operation is possible by installing an inductive reactance (not shown) in addition to the coil ML and the transformer MT.

  In recent years, there are many cases where an IC tag in which an IC that stores the price of the product or various information is embedded or an IC tag for theft prevention is attached to the product. For example, the discharge lamp lighting device has a configuration as shown in FIG. 1, and the secondary wirings 11 and 12 and the secondary wirings 13 and 14 bound by the parallel lines and the flat cabtyre cord are arranged to some extent apart. Then, electromagnetic waves are generated between the secondary wirings 11 and 12 and the secondary wirings 13 and 14. That is, if a product with an IC tag is placed in a region sandwiched between wirings, there is a possibility that the IC tag may malfunction due to the influence of electromagnetic waves. Therefore, in order to prevent the malfunction of the IC tag due to electromagnetic waves, it is desirable to arrange the parallel lines or the flat cabtyre cords so as not to affect the IC tag such as by arranging them in close proximity.

  FIGS. 4 and 5 show the discharge lamp lighting device shown in FIGS. 2 and 3 in which the manner of binding the secondary wires is changed. The secondary wirings 21 to 24 in FIG. 4 and the secondary wirings 31 to 34 in FIG. 5 are bundled together by a four-core cabtire cord or the like. In this case, the capacitance between the secondary wirings is about twice as large as the capacitance between the secondary wirings shown in FIGS. In FIG. 4, the length of the secondary wirings 21 to 24 is 10 [m], the terminals H1 and H1, the terminals L1 and L2 are short-circuited, and the capacitance between the shorted terminals H and L is It was 1540 [pF] when measured.

  An operating frequency of 83 [kHz], a secondary wiring length of 3 [m], a discharge lamp lighting device provided with a high-frequency ballast without binding of secondary wiring, and an operating frequency of 83 [kHz], secondary The brightness of a discharge lamp with a secondary wiring length of 3 [m] is compared with a discharge lamp lighting device equipped with a ballast using a 4-core cabtire cord in the wiring and a length of 10 [m]. On the other hand, the brightness of the discharge lamp with the secondary wiring length of 10 [m] decreased by 57%. On the other hand, the brightness of the discharge lamp of the discharge lamp lighting device provided with a ballast having an operating frequency of 26 [kHz], a 4-core cabtire cord in the secondary wiring, and a length of 10 [m], A high-frequency ballast was provided, and the brightness of the discharge lamp with a secondary wiring length of 3 [m] was only reduced by 1%. Further, during the operation of the ballast, the temperature of the circuit elements such as the switching element, the MOS transistor (not shown) and each transformer rose by 40% or more. The temperature rise of the circuit element could be suppressed to less than 20%. Furthermore, switching noise could be reduced by setting the operating frequency to 26 [kHz].

<Second Embodiment>
In the first embodiment, the discharge lamp lighting device having four secondary wires has been described. In the second embodiment, a discharge lamp lighting device including two secondary wires will be described. By using two secondary wirings, the inter-wiring capacity can be reduced as compared with the secondary wiring described in the first embodiment, but it is necessary to arrange the resonant capacitor C0 in the vicinity of the discharge lamp L. There is. For example, the resonant capacitor C0 is disposed around a socket or the like constituting the discharge lamp L.

  FIG. 6 is a circuit diagram of a discharge lamp lighting device including a ballast 4 having a resonance capacitor C0 and a transformer MT. In order to arrange the resonance capacitor C0 in the vicinity of the discharge lamp L, the resonance capacitor C0 and the transformer MT are arranged. The wiring to be connected is a long wiring as secondary wirings 41 and 42. 7 includes a resonance capacitor C0 and a coil ML, and further includes a filament transformer FT1 and FT2 for preheating the filament of the discharge lamp L and a ballast 5 in which the resonance capacitor C0 is disposed in the vicinity of the discharge lamp L. FIG. 3 is a circuit diagram of a discharge lamp lighting device. Similarly, FIG. 8 is a circuit diagram of a discharge lamp lighting device having a resonance capacitor C0 and a transformer MT, and further including a ballast 6 in which filament transformers F1 and F2 and a resonance capacitor C0 are arranged in the vicinity of the discharge lamp L. It is.

  FIG. 9 includes a resonant capacitor C0 and a transformer MT, and further includes a filament transformer FT for preheating the filament, and a current limiting capacitor FC that prevents the excessive current from flowing through the primary winding of the filament transformer FT. It is a circuit diagram of the discharge lamp lighting device provided with the ballast 7 connected in series with respect to. The filament transformer FT, the current limiting capacitor FC, and the resonant capacitor C0 and the transformer MT, which are disposed in the vicinity of the discharge lamp L, are connected by secondary wires 71 and 72.

  Capacitors CD, C1, and C2 in FIGS. 6 to 9 are for facilitating detection of abnormal operation of the discharge lamp, and for preventing an excessive current from flowing through a low impedance filament winding due to an external short circuit or the like.

  The discharge lamp lighting device in the second embodiment has the same effects as the discharge lamp lighting device in the first embodiment. Furthermore, in any discharge lamp lighting device, since the filament capacity of the 40 [W] to 50 [W] discharge lamp is about 3 [W], the ballasts 1 to 3 described in the first embodiment are used. The ballasts 4 to 7 can be downsized as compared with FIG. The ballast included in the discharge lamp lighting device described in the second embodiment is preferably used as a rapid start type ballast.

An example of the circuit diagram of the discharge lamp lighting device in the first embodiment An example of the circuit diagram of the discharge lamp lighting device in the first embodiment An example of the circuit diagram of the discharge lamp lighting device in the first embodiment An example of the circuit diagram of the discharge lamp lighting device in the first embodiment An example of the circuit diagram of the discharge lamp lighting device in the first embodiment An example of a circuit diagram of a discharge lamp lighting device according to the second embodiment An example of a circuit diagram of a discharge lamp lighting device according to the second embodiment An example of a circuit diagram of a discharge lamp lighting device according to the second embodiment An example of a circuit diagram of a discharge lamp lighting device according to the second embodiment

Explanation of symbols

L Discharge lamp V AC power supply C0 Resonance capacitor ML Coil MT Transformer FT, FT1, FT2 Filament transformer CD, C1, C2, FC Capacitors 1, 2, 3, 4, 5, 6, 7 Ballasts 11-14, 21-24 31-34, 41-44 Secondary wiring 51-54, 61-64, 71-74 Secondary wiring

Claims (2)

AC power supply,
A ballast connected to the AC power source and having a resonant coil and a resonant capacitor;
A discharge lamp that is lit or flashed by electric power supplied from the ballast;
Secondary wiring composed of at least two wirings for electrically connecting the ballast and the discharge lamp;
In a discharge lamp lighting device comprising:
The resonant capacitor has a capacity of 1000 [pF] or more,
The operating frequency of the ballast is 10 to 60 [kHz],
The discharge lamp lighting device characterized in that an inter-wiring capacitance in the secondary wiring is 2000 [pF] or less. AC power supply,
A ballast connected to the AC power source and having a resonant coil and a resonant capacitor;
A discharge lamp that is lit or flashed by electric power supplied from the ballast;
In a discharge lamp lighting device comprising:
The operating frequency of the ballast is 10 to 60 [kHz],
The resonant capacitor has a capacity of 1000 [pF] or more, and the resonant capacitor is disposed in the vicinity of the discharge lamp,
A secondary wiring comprising at least two wirings for electrically connecting the discharge lamp, the resonance capacitor and the resonance coil; and a capacitance between the wirings of the secondary wiring is 2000 pF or less. A discharge lamp lighting device characterized by.

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