JP2010050058A - Electrodeless discharge lamp and lighting fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp and a lighting apparatus, in which stable light output can be obtained even when the ambient temperature is low at the time of light control lighting. <P>SOLUTION: The electrodeless discharge lamp 10 and the lighting apparatus include: a bulb 11 which has a discharge gas consisting of a rare gas and an evaporable metal filled inside, and has a translucent cavity 12 of a bottomed cylindrical shape; an exhaust capillary 13 which is opened from the bottom part of the cavity 12 toward the top portion; amalgam 14 which contains the discharge gas and is housed in the exhaust capillary 13; a coupler 15 consisting of an induction coil 16 to generate induction field in the bulb 11, a ferrite core 17 wound with the induction coil 16, and a heat radiating member 18; and a lighting circuit 19 to generate a high-frequency current. The coupler 15 generates electric discharge in the bulb 11 by the high-frequency current input into the cavity 11 by the lighting circuit 19. The coupler 15 includes a heater 21 which works through a switch 20 that turns on and off according to a starting voltage and a re-ignition voltage in the vicinity of the amalgam 14. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrodeless discharge lamp and a lighting fixture that excites a discharge gas by an electromagnetic field formed by energizing a high-frequency current to an induction coil without having an electrode.

As an example of conventional electrodeless discharge lamps and lighting fixtures, amalgam (mercury) is provided in a bulb in which discharge gas is sealed, and a cylindrical ferrite core and induction coil are provided in a cavity formed in the bulb. There is an electrodeless discharge lamp provided with a coupler (see, for example, Patent Document 1).
In such an electrodeless discharge lamp, the temperature rise of the lamp is small and the ambient temperature characteristic shifts when the dimming lamp is lit compared to when it is fully lit, and when the ambient temperature is low, the mercury vapor pressure becomes too low and the desired pressure is reached. The light output may not be obtained.
Therefore, a heating element such as a heater is provided in the vicinity of the base of the electrodeless discharge lamp, and the mercury vapor pressure is controlled while detecting the temperature of the coldest part with the temperature detecting means.
Japanese Patent Laying-Open No. 2005-1000084 (FIG. 1, paragraph numbers 0029, 0030, 0031)

  However, in the electrodeless discharge lamp disclosed in Patent Document 1, it is necessary to separately provide temperature detecting means, and there is a problem that the structure becomes complicated.

  The present invention has been made to satisfy the above-described demands, and an object thereof is to provide an electrodeless discharge lamp and a lighting fixture capable of obtaining a stable light output even when the ambient temperature is low during dimming lighting. There is.

  An electrodeless discharge lamp of the present invention includes a bulb having a bottomed cylindrical cavity that is filled with a rare gas and a discharge gas composed of a metal that can be vaporized, and has a translucent bottom, and a top portion from the bottom of the cavity. Exhaust narrow tube opened toward the surface, amalgam containing the discharge gas and housed in the exhaust narrow tube, an induction coil generating an electromagnetic field in the bulb, a ferrite core around which the induction coil is wound, and a heat dissipation member In the electrodeless discharge lamp in which the coupler generates a discharge in the bulb by the high-frequency current supplied into the cavity by the lighting circuit, the coupler comprising: a lighting circuit that generates a high-frequency current; The coupler is provided with a heater that operates in the vicinity of the amalgam through a switch that is turned on and off in response to the starting voltage and the re-ignition voltage. And said that you are.

In the present invention, the re-ignition voltage at the time of dimming lighting, that is, the heater switch arranged in the vicinity of the amalgam is turned on according to the voltage level when the arc once disappeared is re-ignited. The amalgam is heated by the heater at the time of dimming lighting when the temperature of the electrodeless discharge lamp is lower than that at times.
Therefore, a stable light output can be obtained at the time of dimming lighting without providing a separate temperature detecting means unlike the conventional one.

  The electrodeless discharge lamp of the present invention is characterized in that the switch is a discharge lamp, and a long afterglow phosphor is applied to the discharge space side of the cavity.

In the present invention, since the switch for turning on and off the heater is a discharge lamp, a simple structure can be obtained without requiring an external circuit.
In the present invention, since the long afterglow phosphor is applied to the cavity, the discharge lamp is turned on at the re-ignition voltage at the time of starting or dimming and the long afterglow phosphor is accumulated. The afterglow brightness can be kept high and the dark place start assist function can be exhibited for a long time.

  The lighting fixture of the present invention uses the electrodeless discharge lamp of the present invention.

  In the present invention, by using the electrodeless discharge lamp of the present invention, it is possible to provide a lighting fixture capable of obtaining a stable light output during dimming lighting.

According to the electrodeless discharge lamp and the luminaire of the present invention, the coupler includes a heater that operates in the vicinity of the amalgam through a switch that is turned on and off in response to the starting voltage and the re-ignition voltage.
Thereby, there is an effect that a stable light output can be obtained even when the ambient temperature is low during dimming lighting.

  Hereinafter, an electrodeless discharge lamp and a lighting fixture according to embodiments of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the electrodeless discharge lamp 10 according to the first embodiment of the present invention is filled with a rare gas and a discharge gas made of a metal that can be vaporized and has a light-transmitting bottom. A valve 11 having a cylindrical cavity 12, an exhaust tube 13 opened from the bottom of the cavity 12 toward the top, an amalgam 14 containing discharge gas and housed in the exhaust tube 13, and an electromagnetic wave in the valve 11 An induction coil 16 that generates a field, a coupler 15 including a ferrite core 17 wound around the induction coil 16 and a heat radiating member 18, a lighting circuit 19 that generates a high-frequency current, and a starting voltage and re-energization in the vicinity of the amalgam 14 in the coupler 15. A heater 21 that operates through a discharge lamp 20 that is turned on and off according to the arc voltage, and a lamp unit 22 is configured by the bulb 11 and the cavity 12. These couplers 15 are assembled detachably. In addition, since a lighting fixture accommodates the electrodeless discharge lamp 10, it abbreviate | omits illustration.

  The bulb 11 is formed in a substantially spherical shape using a glass material having translucency.

  The cavity 12 is a cylindrical body that is formed by using a light-transmitting glass material or the like and has a closed upper end. For this reason, a hollow portion 23 that is a cylindrical space is provided on the side portion of the exhaust thin tube 13.

  The long afterglow phosphor 24 is applied to the cavity 12 on the phosphor film on the discharge space side. Examples of the long afterglow phosphor 24 include europium / dysprosium co-activated strontium aluminate phosphor (SrAl204: Eu, Dy, Sr4Al14025: Eu, Dy), europium / neodymium co-activated calcium aluminate phosphor ( CaAl204: Eu, Nd) and the like.

  An amalgam 14 is accommodated in the exhaust narrow tube 13 together with a rare gas discharge gas such as argon and mercury.

  The amalgam 14 encloses mercury in a metal container 25.

  Here, a support piece 27 connected to the holding body 26 is inserted into the upper open portion of the exhaust thin tube 13.

  In the coupler 15, the induction coil 16 is wound around the outer periphery of the ferrite core 17, and a resin heat radiating member 18 having heat dissipation is assembled to these. The outer diameter of the induction coil 16 and the outer diameter of the cylindrical portion 28 in the heat radiating member 18 are slightly smaller than the inner diameter of the hollow portion 23 of the cavity 12. Therefore, the cylindrical portion 28 of the induction coil 16, the ferrite core 17, and the heat radiating member 18 is fitted in the hollow portion 23 of the cavity 12.

  A protective film and a fluorescent film (not shown) are applied to the inner surface of the lamp portion 22 composed of the bulb 11 and the cavity 12. A base 29 is assembled to the base of the lamp part 22, and the lamp part 22 and the coupler 15 are coupled by the base 29.

  The heater 21 is disposed in the vicinity of the side portion of the amalgam 14 in the hollow portion 23 of the cavity 12.

  As shown in FIG. 3, the induction coil 16 is connected to a lighting circuit 19, and the discharge lamp 20 is connected in series to a secondary coil 30 and a heater 21 configured with one turn. The secondary coil 30 is fitted on the lower side of the induction coil 16 in the ferrite core 17 and receives electromagnetic energy from the induction coil 16.

  As shown in FIG. 4, the envelope of the voltage across the coil of the electrodeless discharge lamp 10 requires a high voltage (starting voltage) across the coil when starting, and once the discharge starts, the voltage across the coil is low. (Sustain voltage). Then, this high voltage (re-ignition voltage) is required every time when dimming lighting is repeatedly turned on and off in a short cycle with a predetermined duty ratio.

  The discharge lamp 20 receives the re-ignition voltage so as to start discharge (switch on) with the voltage generated in the secondary coil 30, and receives the discharge maintenance voltage when the electrodeless discharge lamp 10 is turned on. The voltage generated in the secondary coil 30 is set not to discharge.

  In such an electrodeless discharge lamp 10, a high-frequency electromagnetic field is generated in the induction coil 15 by passing a high-frequency current through the induction coil 15, and the discharge gas is excited and emitted by the high-frequency electromagnetic field to radiate ultraviolet rays. Ultraviolet rays are converted into visible light in the bulb 11 and lighted.

  At this time, a high voltage is applied to both ends of the coil during startup. When discharge starts, the voltage across the coil decreases.

Then, at the time of dimming lighting that repeatedly turns on and off in a short cycle, the discharge lamp 20 is turned on by receiving a re-ignition voltage, the heater 21 is driven, and the amalgam 14 is heated by driving the heater 21.
Therefore, the amalgam 14 is heated by the heater 21 at the time of light control lighting when the temperature of the electrodeless discharge lamp 10 is lowered.

According to the electrodeless discharge lamp 10 described above, the discharge lamp 20 disposed in the vicinity of the amalgam 14 is turned on to drive the heater 21 according to the re-ignition voltage at the time of dimming lighting.
As a result, since a high voltage is generated at both ends of the coil at the time of starting, the discharge lamp 20 is turned on, so that the electrodeless discharge lamp can be reliably started even in an environment where the surroundings are dark. The amalgam 14 is heated by the heater 21 at the time of dimming lighting in which the temperature of the discharge lamp 10 is lowered.
Therefore, a stable light output can be obtained at the time of dimming lighting without providing a separate temperature detecting means unlike the conventional one.

  Moreover, according to the electrodeless discharge lamp 10 of the present invention, since the switch for turning on and off the heater 21 is the discharge lamp 20, a simple structure can be obtained without requiring an external circuit.

  According to the electrodeless discharge lamp 10 of the present invention, the long afterglow phosphor 24 is applied to the cavity 12, so that the discharge lamp 20 is lit at the re-ignition voltage at the time of starting or dimming lighting. Thus, the long afterglow phosphor 24 can be stored to keep the afterglow brightness high, and the dark place start assist function can be exhibited for a long time.

  According to the lighting fixture of the present invention, by using the electrodeless discharge lamp 10 of the present invention, it is possible to provide a lighting fixture capable of obtaining a stable light output during dimming lighting.

(Example)
Next, the Example performed in order to confirm the effect of the electrodeless discharge lamp 10 of this invention and a lighting fixture is described.
(Measurement of ambient light temperature characteristics)
In the examples, the ambient temperature and the relative light quantity were measured to compare the ambient temperature characteristics of the light quantity when the electrodeless discharge lamp was turned on with the comparative example. The measurement results are shown in Table 1. In Table 1, the solid line described as being fully lit represents the measured values of the comparative example and the example, the broken line described as being dimmed is the measured value of the comparative example, and the solid line is the measured value of the example. Value.

  As is apparent from Table 1, it can be seen that good light characteristics can be obtained over a wide temperature range due to the characteristics of the amalgam 14 during full lighting. When this electrodeless discharge lamp is dimmed with duty control by turning on / off, the temperature of the electrodeless discharge lamp is lowered and the temperature of the amalgam 14 is lowered. In this cold state, the ambient temperature characteristic shifts to the high temperature side, so that the amount of light in the comparative example is significantly reduced. On the other hand, in the embodiment, the heater 21 is operated by the re-ignition voltage at the time of dimming lighting and the amalgam 14 is heated, so that the deviation of the ambient temperature characteristic is eliminated and the light quantity decrease at a low temperature is prevented. I know you can.

  In addition, the valve | bulb 11, the nozzle | cap | die 29, etc. which were used by each said embodiment are not limited to what was illustrated, and can be changed suitably.

The longitudinal cross-sectional view explaining the internal structure of the electrodeless discharge lamp of one Embodiment which concerns on this invention FIG. 1 is an enlarged cross-sectional view of the main part of the electrodeless discharge lamp of FIG. Circuit diagram of the electrodeless discharge lamp of FIG. Envelope diagram of the voltage across the coil of the electrodeless discharge lamp of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electrodeless discharge lamp 11 Bulb 12 Cavity 13 Exhaust capillary 14 Amalgam 15 Coupler 16 Inductive coil 17 Ferrite core 18 Heat radiation member 20 Discharge lamp (switch)
21 Heater 24 Long afterglow phosphor

Claims (3)

A bulb having a bottomed cylindrical cavity that is filled with a rare gas and a discharge gas made of a metal that can be vaporized and is translucent;
An exhaust thin tube opened from the bottom of the cavity toward the top;
Amalgam containing the discharge gas and housed in the exhaust tubule;
An induction coil that generates an electromagnetic field in the valve, a ferrite core around which the induction coil is wound, and a coupler that includes a heat radiating member;
A lighting circuit that generates a high-frequency current;
With
In the electrodeless discharge lamp in which the coupler generates a discharge in the bulb by the high-frequency current input into the cavity by the lighting circuit,
The coupler is provided with a heater that operates in the vicinity of the amalgam through a switch that is turned on and off according to a starting voltage and a re-ignition voltage.   2. The electrodeless discharge lamp according to claim 1, wherein the switch is a discharge lamp, and a long afterglow phosphor is applied to a discharge space side of the cavity.   A lighting fixture using the electrodeless discharge lamp according to claim 1.

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