JP2010080241A - Electrodeless discharge lamp device and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp device including a valve of loop shape and capable of stabilizing light output in a wide operating temperature range, and to provide a luminaire. <P>SOLUTION: The electrodeless discharge lamp device 100 includes the valve 1 of loop shape formed of glass with discharge gas and mercury vapor sealed inside; two ferrite cores 3 arranged in a form of covering two parts spaced along the pipe axis direction in the valve 1; lamp lighting induction coils 2 wound around the ferrite cores 3; and a lighting device 4 including a high frequency power supply 4a. Part of the valve 1 is formed with an amalgam storage part 1a storing mercury amalgam 5 for supplying mercury vapor, and an amalgam induction coil 21 for heating the mercury amalgam 5 is wound around a part of the ferrite core 3 and around an amalgam storage part 1c. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrodeless discharge lamp device and a lighting fixture provided with a loop-shaped bulb.

  Conventionally, as shown in FIG. 6, a loop-shaped bulb 1 made of a light-transmitting material and filled with a discharge gas made of a rare gas such as argon and mercury vapor, and in the bulb 1 in the tube axis direction. The two ferrite cores (not shown) are disposed so as to surround the two parts spaced apart from each other and are disposed inside each of the two lamp holders 32 ', and two wound around each ferrite core. Proposed is an electrodeless discharge lamp device comprising an induction coil (not shown) and a lighting device (not shown) connected to each induction coil and including a high-frequency power source (not shown) that supplies a high-frequency current to the induction coil. (See Patent Document 1). Here, an electrodeless discharge lamp is constituted by the bulb 1, each ferrite core, and each induction coil.

  In the electrodeless discharge lamp apparatus having the configuration shown in FIG. 6, when a high frequency current of several hundred kHz is supplied to the induction coil from a high frequency power source, an induction electric field generated inside the bulb 1 constituting the electrodeless discharge lamp by electromagnetic induction. Acts on the discharge gas enclosed in the bulb 1 to generate a discharge, and the mercury present in the bulb 1 is excited to generate ultraviolet rays. In the electrodeless discharge lamp, the fluorescent material applied to the inner surface of the bulb 1 is converted into visible light by the ultraviolet light generated inside the bulb 1 by the fluorescent material applied to the inner surface of the bulb 1. Is used as an electrodeless fluorescent lamp. On the other hand, when the bulb 1 is made of a material having a high ultraviolet transmittance and the phosphor is not coated on the inner surface of the bulb 1, it is used as an electrodeless ultraviolet lamp. These electrodeless fluorescent lamps and electrodeless ultraviolet lamps have a long life because there is no electrode (not shown) that causes a short life inside the bulb 1.

  Generally, in an electrodeless discharge lamp, in order to supply mercury vapor to a discharge space inside a bulb, mercury amalgam is often enclosed inside the bulb. The reason why mercury amalgam rather than pure mercury is often enclosed inside the bulb is that the mercury amalgam enclosed inside the bulb is relatively wide compared to when pure mercury is enclosed In the operating temperature range, the mercury vapor pressure inside the bulb can be stabilized and the temperature dependence of the light output can be reduced.

  In the electrodeless discharge lamp apparatus having the configuration shown in FIG. 6, mercury amalgam (not shown) for supplying mercury vapor is enclosed in the bulb 1, and the mercury vapor pressure inside the bulb 1 is stabilized. In order to maintain the pressure at which output can be obtained, it is necessary to always maintain the temperature of the mercury amalgam at a specified temperature (for example, 70 ° C.) higher than the normal temperature (25 ° C.). Here, in the electrodeless discharge lamp apparatus having the configuration shown in FIG. 6, when the ambient temperature (hereinafter referred to as the operating temperature) is a low temperature lower than the normal temperature, or when the lamp is lit with a lower supply power than the rated lighting. At the time of dimming and lighting, the temperature of the mercury amalgam became lower than the specified temperature, the mercury vapor pressure inside the bulb 1 was extremely lowered, and the luminous efficiency may be greatly lowered. Furthermore, in the electrodeless discharge lamp apparatus having the configuration shown in FIG. 6, when operated at a low temperature for a long period of time, mercury may not evaporate and only rare gas may be discharged. Therefore, it is necessary to arrange mercury amalgam in a place where the temperature is high.

Therefore, in the electrodeless discharge lamp apparatus shown in FIG. 6, mercury amalgam is arranged inside the amalgam storage part 1 c formed in the vicinity of the ferrite core 3 in the bulb 1, and the heat generated in the ferrite core 3 is made of aluminum or the like. The temperature of the mercury amalgam is maintained at the specified temperature or higher by transferring the mercury amalgam to the mercury amalgam through the heat transfer portion 3a formed of the metal.
JP 11-191398 A

  However, in the electrodeless discharge lamp apparatus configured as shown in FIG. 6, particularly when the operating temperature is low, the heat generated in the ferrite core is dissipated before reaching the mercury amalgam, and is sufficiently transmitted to the mercury amalgam. Therefore, the temperature of the mercury amalgam could not be maintained above the specified temperature, and the light output might not be stable.

  The present invention has been made in view of the above-mentioned reasons, and an object of the present invention is to provide an electrodeless discharge lamp device and a lighting fixture that have a loop-shaped bulb and can stabilize light output in a wide operating temperature range. It is to provide.

  In order to achieve the above object, a first aspect of the present invention provides a loop-shaped bulb formed of a light-transmitting material and filled with discharge gas and mercury vapor, and a part of the bulb formed of a magnetic material. A ferrite core arranged to cover the lamp, a lamp lighting induction coil wound around the ferrite core, and a high frequency power source that emits light by exciting a discharge gas by electromagnetic induction by passing a high frequency current through the lamp lighting induction coil And a part of the valve is formed with an amalgam storage part in which mercury amalgam for supplying mercury vapor is stored, and a high-frequency power source is connected with a decrease in mercury vapor pressure inside the valve. In order to maintain the power supplied to the lamp lighting induction coil when the high frequency current flowing through the lamp lighting induction coil decreases, the voltage across the lamp lighting induction coil is increased. It is one that is, the amalgam for induction coil for heating the mercury amalgam, characterized by comprising wound around amalgam housing portion together wound around a portion of the ferrite core.

  According to this invention, when the induction coil for amalgam is wound around the ferrite core and is wound around the amalgam storage part, it is generated in the induction coil for amalgam when a current flows through the induction coil for amalgam. Since heat is reliably and efficiently transferred to the mercury amalgam, it is possible to maintain the mercury vapor pressure inside the bulb by maintaining the mercury amalgam above a specified temperature higher than room temperature over a wide operating temperature range. Therefore, the light output can be stabilized in a wide operating temperature range.

  According to a second aspect of the present invention, the electrodeless discharge lamp device according to the first aspect of the present invention is provided.

  According to this invention, since the electrodeless discharge lamp device according to the invention of claim 1 is provided, a high light output can be obtained in a wide operating temperature range, so that a relatively stable luminous flux can be obtained even if the temperature environment changes greatly. Obtainable.

  According to the first aspect of the present invention, the heat generated in the induction coil for amalgam when current flows through the induction coil for amalgam is reliably and efficiently transmitted to the mercury amalgam, so that it can be applied over a wide operating temperature range. Since the mercury amalgam can be maintained at a specified temperature higher than normal temperature or higher to maintain the pressure of mercury vapor inside the bulb, the light output can be stabilized over a wide operating temperature range.

(Embodiment 1)
Hereinafter, the present embodiment will be described with reference to FIG.

  The electrodeless discharge lamp device 100 of the present embodiment is arranged so as to surround a loop-shaped bulb 1 in which discharge gas and mercury vapor are sealed, and two locations spaced apart in the tube axis direction in the bulb 1. A lighting device having two ferrite cores 3, two lamp lighting induction coils 2 wound around each ferrite core 3, and a high frequency power source 4 a that outputs a constant voltage and supplies a high frequency current to the lamp lighting induction coil 2. 4. Here, the bulb 1, the ferrite core 3 and the lamp lighting induction coil 2 constitute an electrodeless discharge lamp.

  The bulb 1 is made of glass which is a light transmissive material. The valve 1 is formed by joining both end portions of the first U-shaped tube 11 and both end portions of the second U-shaped tube 12 having a shorter length in the tube axis direction than the first U-shaped tube 11. It is formed. Thus, two C-shaped parts connecting two parallel straight portions 1a, one end portions of the two straight portions 1a (left end portions in FIG. 1) and the other end portions (right end portions in FIG. 1). A loop-shaped valve 1 composed of a curved portion 1d is formed.

  A phosphor (not shown) is applied to the inner surface of the bulb 1. Therefore, in the electrodeless discharge lamp included in the electrodeless discharge lamp device 100 of the present embodiment, when ultraviolet rays are generated by emitting mercury contained in the mercury vapor sealed in the bulb 1, the ultraviolet rays are phosphors. Therefore, it can be used as an electrodeless fluorescent lamp. The shape of plasma generated inside the bulb 1 when a high-frequency current is passed through the lamp lighting induction coil 2 is also a loop shape along the tube axis direction of the bulb 1 and extends throughout the bulb 1. Will occur. In the present embodiment, the phosphor is applied to the inner surface of the bulb 1. However, the bulb 1 is formed of a light-transmitting material having a high ultraviolet transmittance, and the phosphor is formed on the inner surface of the bulb 1. An ultraviolet lamp that is not coated may be used.

  In the second U-shaped tube 12, an amalgam storage portion 1 c is formed at a substantially central portion in the tube axis direction so as to protrude to the outside of the valve 1, and inside the amalgam storage portion 1 c, A granular mercury amalgam 5 for supplying mercury vapor to the internal discharge space is arranged. Here, the amalgam storage portion 1c is provided inside the elongated exhaust pipe in which the internal space where one end is welded to the portion corresponding to the second U-shaped tube 12 of the bulb 1 communicates with the discharge space inside the bulb 1. In addition, the other end portion of the exhaust pipe is sealed in a state where the mercury amalgam 5 is arranged. Here, the amalgam storage part 1c rolls the mercury amalgam 5 from the amalgam storage part 1c into the discharge space inside the bulb 1 by reducing the diameter of the one end compared to the diameter of the part where the mercury amalgam 5 is arranged. Can be prevented.

  In addition, in this embodiment, although the case where the granular mercury amalgam 5 was arrange | positioned in the amalgam accommodating part 1c was demonstrated, as shown in FIG. 2, the mercury amalgam 5 is a hole for mercury vapor transmission | permeation (not shown). You may arrange | position inside the amalgam accommodating part 1c in the state accommodated in the certain metal holder 5a.

  Ar gas is sealed in the bulb 1 as a discharge gas. The discharge gas sealed inside the bulb 1 may be krypton, for example.

  The ferrite core 3 is formed in a toroidal shape, and is disposed so as to surround two portions of the valve 1 that are joint portions of the first U-shaped tube 11 and the second U-shaped tube 12. Specifically, the ferrite core 3 is arranged in a form surrounding the left end portion in FIG. 1 in each of the two linear portions 1 a parallel to each other in the bulb 1. The ferrite core 3 is formed of a magnetic material, and a lamp lighting induction coil 2 is wound around a part thereof.

  The lighting device 4 includes a high frequency power source 4a, and the high frequency power source 4a and the lamp lighting induction coil 2 are electrically connected via a lead wire 34. The high frequency power source 4a is connected to the lamp lighting induction coil 2 with a high frequency. Energize current. When a high frequency current is applied to the lamp lighting induction coil 2, an induction electric field is generated inside the bulb 1 by electromagnetic induction, and the discharge gas and mercury vapor in the bulb 1 are excited to emit ultraviolet rays. Here, the high frequency power source 4a lights the lamp when the high frequency current (hereinafter referred to as the first coil current) flowing through the lamp lighting induction coil 2 decreases as the mercury vapor pressure inside the bulb 1 decreases. In order to maintain the electric power supplied to the induction coil, the voltage across the lamp lighting induction coil (hereinafter referred to as coil voltage) is increased.

  By the way, in the electrodeless discharge lamp apparatus 100 of this embodiment, as shown in FIG. 1, the induction coil 21 for amalgam for heating the mercury amalgam 5 is arrange | positioned among the two ferrite cores 3 in FIG. The ferrite core 3 is wound around the amalgam storage portion 1c. Therefore, since heat generated in the amalgam induction coil 21 is reliably and efficiently transmitted to the mercury amalgam 5 when a current flows through the amalgam induction coil 21, the mercury amalgam 5 is generated by the heat generated in the ferrite core 3. The mercury amalgam 5 can be surely heated as compared with the case of heating.

  In this embodiment, the induction coil 21 for amalgam for heating the mercury amalgam 5 is a relatively simple structure wound around a part of the ferrite core 3 and wound around the amalgam storage part 1c. The assembly workability can be improved.

  Next, operation | movement of the electrodeless discharge lamp apparatus 100 of this embodiment is demonstrated.

  When the operating temperature is normal temperature (25 ° C) or when the rated lighting is on, if the power consumed by the electrodeless discharge lamp (hereinafter referred to as lamp power consumption) ignores the coupling coefficient and the loss due to the ferrite core 3, the lamp lights up. This is approximately equal to the product of the high-frequency current flowing in the induction coil 2 and the voltage across the lamp lighting induction coil 2, that is, the power supplied to the lamp lighting induction coil 2. For example, in an electrodeless discharge lamp having a lamp power consumption of 150 W at rated lighting, the power consumed by the amalgam induction coil 21 is about several watts. Becomes dominant. On the other hand, when the operating temperature is a low temperature of room temperature or lower or when dimming lighting, the temperature of the mercury amalgam 5 is reduced to a temperature lower than a specified temperature higher than the normal temperature at which the mercury vapor pressure capable of obtaining a stable light output is maintained, The mercury vapor pressure inside the valve 1 rapidly decreases. When the mercury vapor pressure inside the bulb 1 is reduced, the discharge current (hereinafter referred to as lamp current) flowing inside the bulb 1 is reduced and the first coil current is also reduced. Here, as described above, the high-frequency power source 4a maintains the electric power supplied to the lamp lighting induction coil when the first coil current is reduced as the mercury vapor pressure inside the bulb 1 is reduced. Since the coil voltage is increased, the coil voltage increases when the first coil current decreases.

  Here, since the induction coil 21 for amalgam is wound around the ferrite core 3 similarly to the induction coil 2 for lighting, if the coil voltage increases, the voltage between both ends of the induction coil 21 for amalgam also increases. . Then, since the amount of increase in the electrical resistance value between both ends of the amalgam induction coil 21 when the operating temperature changes is sufficiently smaller than the electrical resistance value of the plasma generated inside the bulb 1, it can be ignored. The current flowing through the amalgam induction coil 21 (hereinafter referred to as the second coil current) increases by the amount of the coil voltage of the lamp lighting induction coil 2 being high. Therefore, since the second coil current increases when the operating temperature is a low temperature below room temperature or when dimming is turned on, the amount of heat generated by the amalgam induction coil 21 is increased and the amalgam induction coil 21 is wound. The amalgam storage portion 1c is further heated.

  Next, an example of this embodiment will be described.

  In the present embodiment, the bulb 1 is a first U-shape formed by bending a straight tubular body having an outer diameter of 38 mm formed of Pyrex (registered trademark) which is a translucent material. The tube 11 and the second U-shaped tube 12 are joined, and a loop shape having an outer diameter of a cross section of 38 mm and a length in the tube axis direction of 500 mm is used. Further, the mercury amalgam 5 is made of a Bi—In—Hg alloy having a mercury content of about 10 mg, and the amount of ultraviolet light emitted from the mercury present in the bulb 1 is maximized inside the bulb 1. Thus, Ar gas is sealed by about 133 Pa. The ferrite core 3 has an inner diameter of 42 mm, an outer diameter of 72 mm, and a width of 33 mm. The lighting device 4 of the present embodiment includes a high frequency power source 4a that generates a high frequency current having a frequency of about 135 kHz.

  In addition, the amalgam induction coil 21 of this embodiment is formed of a nichrome wire, wound around a part of the ferrite core 3 for 3 turns, and wound around the amalgam storage part 1c for 3 turns.

  Next, a lighting experiment for measuring the light output from the electrodeless discharge lamp while performing various changes in the electric power (lamp input) supplied to the lamp lighting induction coil 2 at room temperature was performed for this example and the comparative example. The results will be described. In FIG. 3, relative light output (relative light output) at various lamp inputs is shown with the light output when the lamp input is 110 W (at rated lighting) being 1. The electrodeless discharge lamp device of the comparative example is different from the present embodiment in that the amalgam induction coil 21 is not wound around the ferrite core 3 and the amalgam storage portion 1c. As shown in FIG. 3, in the comparative example, when the lamp input is smaller than that at the time of rated lighting, particularly when the lamp input is reduced to 80 W or less, the mercury vapor pressure in the bulb 1 rapidly decreases, and the relative light output On the other hand, in this embodiment, even if the lamp input is reduced to 80 W or less, the mercury vapor pressure in the bulb 1 is not greatly reduced, and the relative light output is not greatly reduced. Was confirmed.

  A discussion of the results shown in FIG. 3 is shown. In this embodiment, since the lamp current is large and the first coil current is large at the rated lighting time, the coil voltage can be kept low by the lighting device 4, so the second coil current is relatively small and the amalgam induction coil 21 is used. The calorific value of is also small. Here, when the lamp input is decreased, the temperature of the mercury amalgam 5 is decreased, the mercury vapor pressure inside the bulb 1 is decreased, the lamp current is decreased, and the first coil current is also decreased. On the other hand, the coil voltage increases as the lamp lighting coil current decreases as the lighting device 4 is controlled so that the power supplied from the lamp lighting induction coil 2 is constant as described above. As a result, the second coil current increases and the amount of heat generated by the amalgam induction coil 21 partially wound around the amalgam storage part 1c increases, so that the mercury disposed inside the amalgam storage part 1c. It is considered that the amalgam 5 is easily heated, and a rapid decrease in mercury vapor pressure inside the bulb 1 is suppressed, and a large decrease in relative light output is suppressed. That is, in the present embodiment, the above-described high-frequency power source 4a is used, and the current flowing through the amalgam induction coil 21 increases as the mercury vapor pressure inside the bulb 1 decreases, and the mercury amalgam 5 is more easily heated. As a result, even when the lamp input is low and the mercury vapor pressure inside the bulb 1 is low, such as during dimming, the mercury amalgam 5 can be maintained at a specified temperature higher than the normal temperature. Similarly, when the operating temperature is a low temperature lower than the normal temperature and the vapor pressure of mercury inside the bulb 1 is low, the mercury amalgam 5 can be maintained at a specified temperature higher than the normal temperature. That is, in this embodiment, the mercury vapor amalgam can be maintained at a specified temperature higher than normal temperature over a wide operating temperature range including low temperature lower than normal temperature, and the mercury vapor pressure inside the bulb can be maintained. The light output can be stabilized over a wide operating temperature range.

  Therefore, it is possible to maintain the mercury vapor pressure inside the bulb by maintaining the mercury amalgam above the specified temperature higher than the normal temperature over a wide operating temperature range including the low temperature below the normal temperature. The light output can be stabilized. Further, since the lamp current is increased and the second coil current is decreased, heating of the mercury amalgam 5 is suppressed, so that the mercury vapor pressure inside the bulb 1 can be suppressed from extremely increasing. Therefore, it is possible to suppress a decrease in light output due to the mercury vapor pressure inside the bulb 1 being too high, so that the light output can be stabilized over a wide operating temperature range.

  In the electrodeless discharge lamp device 100 of the present embodiment, the plasma may be generated inside the amalgam storage part 1c in which the mercury amalgam 5 in the bulb 1 is arranged. In this case, the amalgam induction coil 21 may be formed of Cu, Ag or the like having a low electrical resistance. Moreover, in order to heat the amalgam storage part 1c more efficiently, you may increase the number of turns of the induction coil 21 for amalgam wound around the amalgam storage part 1c suitably.

  In the present embodiment, the example in which the amalgam induction coil 21 is wound around one of the two ferrite cores 3 has been described. However, as shown in FIG. In this case, the number of turns of the amalgam induction coil 21 wound around the ferrite core 3 can be increased to increase the amount of heat generated in the amalgam storage portion 1c. Further, the mercury amalgam 5 can be heated more effectively as the number of turns of the amalgam induction coil 21 wound around the amalgam storage portion 1c is larger.

  Furthermore, the heat insulation effect inside the amalgam storage part 1c is improved by covering the amalgam storage part 1c around which the induction coil 21 for amalgam is wound with a heat insulating material (not shown) such as alumina fiber. Also good.

(Embodiment 2)
The lighting fixture 30 provided with the electrodeless discharge lamp apparatus 100 demonstrated in Embodiment 1 in FIG. 5 is shown. This lighting fixture is used as a tunnel lamp, for example.

  The lighting fixture 30 of the present embodiment includes a U-shaped fixture main body 31 having a rectangular main piece 31a in plan view and two side pieces 31b formed by bending both longitudinal ends of the main piece 31a. And two electrodeless discharge lamp devices 100 (see FIG. 1) housed inside the instrument main body 31. As shown in FIG. 5, the electrodeless discharge lamp device 100 is arranged such that the amalgam storage portion 1 c of the bulb 1 is located on both ends of the instrument main body 31. In each electrodeless discharge lamp apparatus 100, each of the two ferrite cores 3 (see FIG. 1) around which the lamp lighting induction coil 2 and the amalgam induction coil 21 are wound is disposed inside the first lamp holder 32. Has been. Here, the first lamp holder 32 is fixed to the main piece 31 a of the instrument body 31. Further, a part of the bulb 1 of the electrodeless discharge lamp device 100 opposite to the side on which the amalgam housing portion 1c is formed is supported by a second lamp holder 33 fixed to the main piece 31a. Thus, the electrodeless discharge lamp included in each electrodeless discharge lamp device 100 is fixed to the instrument body 31 by the two first lamp holders 32 and the second lamp holder 33. Further, in the instrument main body 31, one end of the two side pieces 31b that are continuous with both ends in the longitudinal direction of the main piece 31a is provided with a flange 31c extending in a direction away from each other in the longitudinal direction of the instrument main body 31. 31c is provided, and the translucent plate 35 made of glass or the like is fixed in contact with the two flange portions 31c and 31c.

  Since the lighting fixture of the present embodiment includes the electrodeless discharge lamp device 100 described in the first embodiment, a high light output can be obtained in a wide operating temperature range. Even if it changes, a relatively stable light beam can be obtained.

1 is a schematic plan view of an electrodeless discharge lamp device according to Embodiment 1. FIG. It is principal part explanatory drawing same as the above. It is a schematic plan view of the electrodeless discharge lamp apparatus same as the above. It is operation | movement explanatory drawing same as the above. The lighting fixture of Embodiment 2 is shown, (a) is a schematic bottom view, (b) is a schematic side view. It is a schematic plan view which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve | bulb 1c Amalgam storage part 2 Inductive coil 3 for lamp lighting Ferrite core 4 Lighting device 4a High frequency power supply 5 Mercury amalgam 21 Induction coil 30 for amalgam Lighting equipment 100 Electrodeless discharge lamp device

Claims (2)

  A loop-shaped bulb formed of a translucent material and enclosing discharge gas and mercury vapor therein, a ferrite core formed of a magnetic material and arranged to cover a part of the bulb, and wound around the ferrite core It is equipped with a rotating lamp lighting induction coil and a high frequency power source that excites the discharge gas by electromagnetic induction by passing a high frequency current through the lamp lighting induction coil and supplies mercury vapor to a part of the bulb When an amalgam storage part is formed in which mercury amalgam is stored inside, the high-frequency power supply decreases when the high-frequency current flowing through the induction coil for lamp lighting decreases as the mercury vapor pressure in the bulb decreases. In order to maintain the power supplied to the induction coil for lighting, it increases the voltage across the induction coil for lamp lighting, and heats the mercury amalgam. Amalgam for induction coil for the electrodeless discharge lamp device, characterized by comprising wound around amalgam housing portion together wound around a portion of the ferrite core.   A luminaire comprising the electrodeless discharge lamp device according to claim 1.

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