JP2006236919A - High pressure metallic vapor discharge lamp and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure metallic vapor discharge lamp in which attenuation of an ultraviolet radiation amount reaching an electrode is small and which can be easily started and surely lit, in a small and low-rated-output high pressure discharge lamp using an ultraviolet radiation starter element as starting aids while arranging a hollow tube surrounding an arc tube; and to provide a luminaire using the discharge lamp. <P>SOLUTION: This high pressure metallic vapor discharge lamp L comprises: the arc tube 5 having a pair of electrodes 6A and 6B in an arc tube bulb 51 and a discharge medium enclosed therein; the hollow tube 8 arranged by surrounding the arc tube 4; power feed members 3a and 3b with the arc tube 5 and supporting members 4a and 4b for supporting both ends of the hollow tube 8 attached thereto and connected to introduction conductors 63, 63 of the arc tube 5; the ultraviolet radiation starter element 7 arranged by facing at least a part thereof to the inside of the hollow tube 8 and connected to the power feed members 3a and 3b; and an outer tube bulb 51 with the arc tube 5, the hollow tube 8, the ultraviolet radiation starter element 7, the supporting members 4a and 4b and the power feed members 3a and 3b housed therein. This luminaire 9 using the discharge lamp L is also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a high-pressure metal vapor in which an arc tube and a translucent hollow tube surrounding the arc tube are supported by a support member in an outer tube bulb, and an ultraviolet radiation starting element for starting is provided on the support member. The present invention relates to a discharge lamp and a lighting fixture using the discharge lamp.

  High-pressure metal vapor discharge lamps that provide high efficiency and high color rendering, such as metal halide lamps, have halides enclosed in the arc tube, resulting in insufficient initial electrons due to electron adsorption by the halogen and poor starting characteristics. There is.

Therefore, as a measure to increase the initial electrons, conventionally, radioactive materials such as promethium Pm ¹⁴⁷ and krypton Kr ⁸⁵ are enclosed in the arc tube to facilitate electron emission between the electrodes at the start. It was. However, encapsulating a radioactive substance inside the arc tube requires strict management for handling and storage of the radioactive substance in the production of the arc tube, and in recent years, a means for assisting starting to replace such a radioactive substance. Is desired.

  Therefore, as another means for assisting starting, Japanese Patent Application Laid-Open No. 1-134848, Japanese Patent Application Laid-Open No. 1-134849, and Japanese Patent Publication No. 7-7662 irradiate the arc tube such as a metal halide lamp with ultraviolet rays at the time of starting. There is disclosed a high-pressure metal vapor discharge lamp that includes a starting element that uses a high-pressure pulse and ultraviolet light from a glow starter (lighting tube).

  The former high-pressure metal vapor discharge lamp by ultraviolet irradiation has a high pulse voltage supplied from a ballast when the discharge lamp is turned on, and a pair of electrodes of an arc tube and an internal conductive member and an external conductive member that the ultraviolet radiation starting element has. Are applied to each other and discharged within the bulb of the ultraviolet radiation starting element to generate ultraviolet rays. By irradiating the ultraviolet rays toward the inside of the arc tube, electrons are emitted from the surface of the electrode, and the number of initial electrons increases, and the inside of the arc tube In this case, the electric discharge is likely to occur and the starting is performed.

  The latter glow starter (lighting tube) is filled with argon gas or mercury in a bulb to form an ultraviolet radiation starting element, and ultraviolet rays generated from argon gas or mercury by glow discharge of the glow starter are irradiated toward the electrodes. As a result, the number of initial electrons is increased, and the discharge lamp is started by generating a high-pressure pulse from the ballast when the bimetal is opened on the same principle as the glow starter of the fluorescent lamp.

  Moreover, this high-pressure metal vapor discharge lamp has a pressure in the arc tube at the time of lighting of about 100 kPa to 500 kPa, depending on the lamp power and size, as the name implies. When the internal pressure rises due to deterioration, scratches, or abnormal current caused by a malfunction of the lighting circuit device, the arc tube bulb may burst due to failure to withstand the pressure.

  If this arc tube bulb is ruptured, fragments such as bulbs that form the arc tube may scatter and collide with the outer bulb, and the outer bulb may also be damaged and scatter these fragments outside the instrument. was there.

  Therefore, as a countermeasure, a protective cover member made of translucent tempered glass or a wire mesh is provided at the opening of the lighting fixture, and when the discharge lamp ruptures, the protective cover member receives fragments and the like. Protective measures have been taken to prevent falling or scattering outside the device.

  However, providing a protective cover member at the opening of this instrument may cause unwanted light reflection, light absorption, light shielding, etc., or the cover member may become dirty and reduce visible light transmittance over time, This is a factor that lowers the luminous efficiency of the fixture, and cleaning this dirt has been very troublesome in the case of a lighting fixture at a high place.

  Moreover, as a countermeasure on the discharge lamp side, an anti-reflection coating is formed on the outer surface of the outer bulb with a material such as a translucent resin so that the fragments do not scatter and fall. The highest fluororesin material is about 260 ° C., and its application was limited depending on the type and output of the discharge lamp.

  Therefore, as another countermeasure, for example, as described in JP-A-5-121047, JP-A-6-295708, JP-A-11-288696, etc., an arc tube is surrounded by an arc tube bulb. A heat-resistant translucent hollow tube made of the same material as above is interposed, and even if the arc tube bulb breaks and scatters, it collides with this hollow tube and weakens the scattered energy, so that fragments etc. It is known and used in many cases to prevent direct flight and to mitigate the impact and prevent damage to the outer tube valve.

The inventors of the present invention, in this type of high-pressure metal vapor discharge lamp, surround the arc tube in order to prevent scattering of fragments when the arc tube bulb bursts in the outer bulb and to improve the luminous characteristics of the arc tube. An invention in which a hollow tube to be heated and a starting circuit constituent member in which the ultraviolet radiation starting element for assisting starting is arranged at a predetermined position in a virtual extension line of the hollow tube outside the hollow tube are provided. I applied. (Patent Document 1)
JP 2003-1000025 A

  As described in the above-mentioned technical document 1, a lamp provided with a starting tube constituent member having a hollow tube surrounding the arc tube and an ultraviolet radiation starting element in the arc tube bulb has a simple configuration and high economic efficiency. Has the advantage of becoming.

  However, if the distance between the electrode provided in the arc tube and the ultraviolet radiation starting element is long, the amount of ultraviolet radiation reaching the electrode may be attenuated and initial electrons may not be sufficiently obtained. In a low-power high-pressure metal vapor discharge lamp that wants to reduce the size of the outer bulb, the characteristics of the ultraviolet radiation starting element deteriorate due to the volume relationship in the outer bulb and the heating when sealing the outer bulb and the stem. In some cases, the location of the ultraviolet radiation starting element is problematic.

  The present invention has been made in view of the above circumstances. In a high-pressure discharge lamp with a small, low-rated output, which is provided with a heat-resistant and light-transmitting hollow tube surrounding the arc tube and uses an ultraviolet radiation starting element as a starting aid, It is an object of the present invention to provide a high-pressure metal vapor discharge lamp that can easily start the lamp with a small attenuation of the amount of ultraviolet radiation that reaches the lamp, and a lighting fixture using the discharge lamp.

  The high-pressure metal vapor discharge lamp according to claim 1 of the present invention includes a light-emitting tube in which a pair of electrodes are sealed in a heat-resistant and light-transmitting light-emitting tube bulb via an introduction conductor and a discharge medium is sealed. Cylindrical hollow tube made of a heat-resistant translucent member disposed so as to surround the periphery of the arc tube, a support member that supports both ends of the arc tube and the hollow tube, and introduction of the arc tube A power supply member connected to a conductor, an ultraviolet radiation starting element supported by the support member or the power supply member and disposed so as to at least partially face the hollow tube, the arc tube, the hollow tube, and the ultraviolet radiation And an outer tube valve that accommodates a starting element, a support member, and a power supply member.

  In the present invention, the ultraviolet radiation starting element, in which at least a part of the ultraviolet radiation starting element such as an enhancer generating ultraviolet light is disposed in the hollow tube, is brought close to the electrode in the arc tube. The upper and lower electrodes of the arc tube and the ultraviolet radiation starting element connected in parallel to the electrodes are energized at the same time, and the ultraviolet radiation starting element disposed close to the electrode as a starter is charged with argon gas or mercury by an internal glow discharge. The amount of ultraviolet rays generated from the electrode increases, the initial electron count increases, and the pulse voltage from the ballast of the lighting circuit device connected to the discharge lamp is applied to the electrode, making it easy to start the discharge lamp Can be done.

  Also, not only the ultraviolet rays going from the ultraviolet radiation starting element toward the inside of the arc tube, but also a part of the ultraviolet rays going toward the hollow tube is reflected by the wall surface of the hollow tube and radiated toward the far electrode to increase the initial electrons. The startability can be increased.

  In addition, since the ultraviolet radiation starting element is located in the hollow tube, when sealing the downsized outer tube valve and the stem, the thermal effect transferred from the inner surface of the outer tube valve to the ultraviolet radiation starting device is affected. Can be reduced.

  The high-pressure metal vapor discharge lamp according to claim 2 of the present invention has a total length of the discharge lamp of 150 mm or less and a length U from the end face of the hollow tube to the tip of the ultraviolet radiation starting element facing inward. And the length D from the end face of the hollow tube on the side where the ultraviolet radiation starting element is disposed to the tip of the electrode adjacent to the inside of the arc tube, 0 <U / D ≦ 1.

  The present invention is applied particularly to a small-sized and low-power high-pressure metal vapor discharge lamp, and has the same effect as that of the first aspect.

  The high-pressure metal vapor discharge lamp according to claim 3 of the present invention is characterized in that the ultraviolet radiation starting element is an enhancer or a glow starter.

  The ultraviolet radiation starting element includes an enhancer, a glow starter (lighting tube), and the like, and can emit ultraviolet rays having a wavelength of at least 200 nm to 460 nm to emit initial electrons from the electrode surface in the arc tube.

  The high-pressure metal vapor discharge lamp according to claim 4 of the present invention is characterized in that the hollow tube has a length covering at least the inner end portion of the arc tube bulb.

  The longer the hollow tube is, the more it can be prevented from scattering glass pieces or the like when the arc tube bulb is ruptured. However, it is sufficient that at least the inner end portion of the arc tube is covered. In addition, the inner end portion that forms the coldest portion of the valve is kept warm, thereby providing a predetermined action. The inner end portion of the arc tube refers to a space region in the bulb excluding the sealing portion (sealing portion) at the bulb end portion.

  According to a fifth aspect of the present invention, there is provided a lighting fixture comprising a fixture main body, the high-pressure metal vapor discharge lamp according to any one of the first to fourth aspects disposed within the fixture main body, and the high-pressure metal vapor. And a lighting circuit device connected to the discharge lamp.

  Since the high-pressure metal vapor discharge lamp with improved starting characteristics according to any one of claims 1 to 4 is incorporated, the lamp can be turned on in a short time, and even if the arc tube bulb is broken, the member fragments can be removed. A highly safe lighting apparatus that is not scattered can be provided.

  According to the first aspect of the present invention, since the ultraviolet radiation starting element such as an enhancer is disposed in the vicinity of the arc tube of the heat-resistant translucent hollow tube, the amount of ultraviolet irradiation to the electrodes can be increased, and the gap between the electrodes can be increased. Discharge is promoted and can be started easily in a very short time (about 20 to 70% shorter than the conventional one).

  In addition, since the arc tube and the ultraviolet radiation starting element are surrounded by the hollow tube, the function of keeping the arc tube warm and preventing the scattering of the member when the arc tube is broken and the ultraviolet radiation starting element is connected to the outer tube valve and the stem. Therefore, it is possible to provide a metal vapor high-pressure discharge lamp in which thermal deterioration during sealing is reduced, and start-up characteristics, light emission characteristics, and safety are improved.

  According to the second aspect of the present invention, it is possible to provide a discharge lamp having the same effect as that of the first aspect, particularly when applied to a small metal vapor high pressure discharge lamp having a low rated output.

  According to the invention of claim 3, by using an enhancer or a glow starter capable of emitting a small and effective ultraviolet radiation as the ultraviolet radiation starting element, it is possible to reduce the size of the discharge lamp and improve the starting characteristics.

  According to the invention of claim 4, since the arc tube and the ultraviolet radiation starting element are surrounded by the hollow tube, the emission characteristics and safety similar to those of the above-mentioned claim 1 can be improved. The probability that the ultraviolet rays reflected from the wall surface irradiate the electrode can be increased.

  According to the invention of claim 5, since the high-pressure discharge lamp having the effects described in claims 1 to 4 is incorporated, the starting characteristics and the light emission characteristics are improved, and a highly safe lighting apparatus is provided. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a front view showing an outline of a metal halide lamp as a high-pressure metal vapor discharge lamp according to the present invention, FIG. 2 is an end view showing an outline of a cut surface along the line aa in FIG. 1, and FIG. FIG. 4 is an enlarged front view showing an ultraviolet radiation starting element arranged in the outer tube bulb in FIG. 1. FIG. 4 is an enlarged sectional front view showing the arc tube portion arranged in the outer tube bulb in FIG.

  The metal halide lamp L shown in FIG. 1 has a long power supply member 3a on one of a pair of inner conductors 2a and 2b led out from a stem 2 sealed at one end of an outer tube bulb 1, and a short power supply on the other. The member 3b is connected, and the arc tube 5, the ultraviolet radiation starting element 7 and the luminous tube 5 and the ultraviolet radiation starting element 7 are surrounded by support members 4a and 4b provided above and below the middle portion of the long power supply member 3a. The end portion of the heat-resistant translucent hollow tube 8 is supported.

  More specifically, the outer tube bulb 1 has a straight tube shape (T shape) made of translucent hard glass such as borosilicate glass, and is closed in a substantially hemispherical shape on the lower side in the figure. And a neck portion 12 on the upper side, a seal portion (not shown) with the stem 2 is formed on the neck portion 12 side, and an E-shaped base 10 is attached to cover the seal portion. Yes.

  As shown in an enlarged view in FIG. 3, the arc tube 5 is made of an alumina transparent material in which small-diameter cylindrical portions 53a and 53b connected to both ends of a substantially spherical bulging portion 52 by continuous curved surfaces. An arc tube bulb 51 that forms a discharge vessel made of a photoceramic is provided, and a wire made of niobium or the like that penetrates through the distal ends of the small diameter cylindrical portions 53a and 53b of the arc tube bulb 51 and is connected to the electrodes 6A and 6B. The lead-in conductors 63 and 63 have a vertically symmetrical structure in which the heat-resistant sealing agents 64 and 64 are hermetically sealed.

  The introduction conductors 63 and 63 include an outer conductor portion 66 led out of the arc tube bulb 51, and a coil-shaped portion in which a molybdenum wire is wound at a portion where the outer conductor portion 66 is extended into the small diameter cylindrical portions 53a and 53b. 65. The electrodes 6A and 6B are butt welded to each other through a coil-shaped portion 65, and an electrode shaft 62 made of a tungsten wire with the tip side facing the bulging portion 52 side, and a tungsten thin wire at the tip of the electrode shaft 62. The coiled electrode 61 is wound.

  The coil-shaped portion 65 is formed when the gap between the electrode shaft 62 penetrating the small-diameter cylindrical portions 53a and 53b and the inner wall surfaces of the small-diameter cylindrical portions 53a and 53b is large. The coil may be wound so that the gap is as small as 0.1 mm or less, and the outer surface of the coil may be in contact with the inner surfaces of the small-diameter cylindrical portions 53a and 53b. Further, the coiled electrode 61 at the tip of the electrode shaft 62 is not essential, and the tip of the electrode shaft 62 may perform an electrode function.

  Also, in the bulb 51 of the arc tube 5, a starting and buffer gas containing, for example, argon Ar as a discharge medium, and metal halides such as sodium iodide, thallium iodide, indium iodide and thulium iodide as the luminescent metal. And mercury are enclosed.

  The heat-resistant translucent hollow tube 8 has a cylindrical shape made of quartz glass with upper and lower ends opened, surrounds the arc tube 5 with a predetermined interval, and at least the inner end portion of the arc tube bulb 51. It is arranged with the length which covers.

  The power supply members 3a and 3b that are connected to the inner conductors 2a and 2b of the stem 2 and extend into the outer tube valve 1 have a linear or plate shape made of molybdenum, stainless steel, or the like, and one long power supply member 3a. Is connected to an outer conductor portion 66 led out from the arc tube 5, and support members 4a and 4b are attached above and below the middle portion. The other power supply member 3 b is connected to the outer conductor portion 66 led out from the arc tube 5. Further, a getter 40 or the like can be attached to the power supply members 3a and 3b.

  The support members 4a and 4b are formed by punching a thin plate made of stainless steel, iron-nickel alloy or the like into a spider shape or a disc shape, for example, a plurality of legs around an annular land 42 provided with a through hole 41 in the center. , 45,..., 46 (some of them are not shown here, but there are one leg part 43 and three leg parts 44 and 45 at substantially equal angles. .., 45,..., 46,... Are bent or held upward, downward, laterally, etc. The ultraviolet radiation starting element 7 and the heat-resistant translucent hollow tube 8 can be supported.

  That is, the support members 4a and 4b have the leg portions 43 fixed on the upper and lower sides of the middle portion of the long power supply member 3a so as to be orthogonal to the axis of the outer tube bulb 1 and are small-diameter cylindrical shapes at both ends of the arc tube 5. The portions 53a and 53b are loosely passed through the through holes 41 in the center of the support members 4a and 4b.

  Further, the flat surfaces of the plurality of leg portions 44 provided on the support members 4a and 4b are in contact with the end surfaces of the hollow tube 8, and the hollow tube 8 is supported with the upper and lower end surfaces sandwiched therebetween. In addition, the tip ends of the plurality of leg portions 44,... Are inclined and bent in a direction away from the hollow tube 8, and elastically contact the inner wall surface of the outer tube valve 1. The plurality of leg portions 45 are bent in the direction inside the hollow tube 8 and elastically contact the inner wall surface of the hollow tube 8.

  In addition, the leg portion 46 provided on the support member 4a located on the top portion 11 side of the outer tube bulb 1 is bent to extend along the arc tube 5 axis, and is connected and fixed to the introduction conductor 63 extending from the small-diameter cylindrical portion 53a. In addition, the three leg portions 46 (not shown) provided on the support member 4b located on the neck portion 12 side are small-diameter cylindrical portions that are loosely passed through the through holes 41. 53b is pressed from the outside so as to be positioned on the central axis.

  The ultraviolet radiation starting element is an enhancer 7, and as shown in an enlarged view in FIG. 4, a sealing made of molybdenum wire or the like in a sealing portion 72 formed at the end of an ultraviolet permeable airtight valve 71 made of quartz glass. A lead wire 73 also serving as a wire is hermetically sealed, and an electrode 74 constituting a foil-like or linear internal conductive member made of molybdenum or the like is connected in the ultraviolet radiation portion 75 of the hermetic bulb 71, and is connected to the outside of the bulb 71. The derived lead wire 73 is connected to the other power supply member 3b. The airtight valve 71 is filled with a rare gas such as argon.

  The enhancer 7 is formed of a thin metal plate on the outer peripheral portion of the hermetic bulb 71, with the ultraviolet radiation portion 75 on the electrode 74 side of the hermetic bulb 71 facing the inside of the hollow tube 8 and substantially along the arc tube 5 axis. The external conductive member 76 also serving as a belt-like holding member is wound and held, and its end is connected and fixed to the power supply member 3a. The external conductive member 76 may be formed by winding a conductive wire in a spiral shape a plurality of times.

  The arc tube 5, the enhancer 7 and the hollow tube 8 in the outer tube bulb 1 are supported and fixed or electrically connected to the power supply members 3a and 3b and the support members 4a and 4b with the above-described configuration. .., 45,..., 46,... Are approximately on the central axis of the lamp (outer tube bulb) shaft by elastic contact with the inner wall surface of the tube bulb 1, the wall surface of the hollow tube 8, and the outer peripheral surface of the small-diameter cylindrical portion 53b. Even if a slight vibration or impact is applied, the arc tube 5 and the like can be prevented from being damaged.

  A convex portion such as a hemispherical shape or a bent shape may be formed in a portion that elastically contacts other parts such as each leg portion 44,..., 45,. Further, the power supply members 3a and 3b, the support members 4a and 4b, and the conductive members can be connected and fixed to each other by means such as welding, brazing, and caulking, and the inner conductors 2a and 2b and the power supply member 3a. , 3b, conductive members, etc. are not specially provided, and the number of members may be reduced by combining them by changing the length and arrangement direction.

  A high-pressure metal vapor discharge lamp L shown in FIG. 1 is a vertical, horizontal state or inclined state as a metal halide lamp L having a double tube structure in which an arc tube 5 is accommodated in a straight tube (T-shaped) outer tube bulb 1. Lights on.

  10 parts of the base of the metal halide lamp L are attached to the socket, and energized from a power source through a lighting circuit device (not shown) having a ballast and the like.

  As the lighting circuit device, a rectangular wave lighting circuit device or a magnetic excitation type ballast lighting circuit device such as a choke coil type or a transformer type can be used for lighting. For example, a high-pressure discharge lamp can be lit with a rectangular wave with a lighting frequency of 100 Hz to 1 kHz and a secondary open circuit voltage from a ballast of 150 to 400V.

  The discharge lamp L connected to the lighting circuit device is electrically connected to a terminal portion (not shown) of the base 10 at the time of starting, and is connected to the inner conductor 2a (2b) -feed member 3a / support member 4a (3b)- The electrodes 6A and 6B and the inner conductor 2a (2b) in the arc tube 5 through the outer conductor 66 (66) -introducing conductor 63 (63) and the inner conductor 2a (2b) -the feeding member 3a (3b) -the outer conductive member 76 (lead wire 73) ), A high voltage pulse voltage is applied to the electrode (internal conductive member) 74 of the enhancer 7.

  By applying this voltage, a discharge is generated between the electrode 74 and the external conductive member 76 constituting the internal conductive member of the enhancer 7 having a lower impedance than that between the electrodes 6A and 6B in the arc tube 5. As a result of this discharge, ultraviolet rays are generated in the enhancer 7 and are transmitted through the ultraviolet radiation portion 75 of the hermetic bulb 71 so that the ultraviolet rays are radiated to the outside and irradiate the electrodes 6A and 6B in the arc tube 5.

  In the present invention, since the enhancer 7 is disposed in the vicinity of the arc tube 5, the amount of ultraviolet radiation directed toward the electrodes 6A and 6B can be increased, and at this time, the axial direction of the arc tube 5 and the hollow tube 8 can be increased. The ultraviolet rays reflected in the direction and reflected by the wall surface of the hollow tube 8 reach the other electrode 2B, and the amount of ultraviolet rays irradiated to both the electrodes 6A and 6B can be increased as compared with the prior art.

  Then, the discharge between the electrodes 6A and 6B is promoted, and the arc tube 5 is easily started within an extremely short time of about 2 to 4 seconds (about 20 to 70% shorter than the conventional one). Stable lighting can be sustained.

  That is, when the electrodes 6A and 6B existing in the discharge space of the arc tube 5 are irradiated with ultraviolet rays having energy higher than the work function of the electrode constituent metal, electrons are emitted from the surfaces of the electrodes 6A and 6B. The number increases to easily cause discharge.

  If the discharge shifts between the electrodes 6A and 6B, the impedance between the electrodes 6A and 6B decreases, and the impedance between the internal conductive member 74 and the external conductive member 76 that form the electrode of the enhancer 7 is greater. It becomes high and the discharge in the enhancer 7 stops.

  As described above, the high-pressure metal vapor discharge lamp L of the present invention is provided with the ultraviolet radiation starting element composed of the enhancer 7 in the vicinity of the electrodes 6A and 6B of the arc tube 5 in the hollow tube 8 at the time of starting. As a result of the increase in the initial number of electrons in the arc tube 5, it is possible to provide a discharge lamp L with improved start-up characteristics that facilitates the generation of discharge and is reliable, and shortens the time required to start the lamp L.

  Further, in this discharge lamp, the outer bulb 1 and the stem 2 are sealed, but the ultraviolet radiation starting element 7 is disposed in the hollow tube 8, so that the ultraviolet ray by a heating burner or the like at the time of sealing is provided. As a result of the temperature rise of the radiation starting element 7 being reduced, it is possible to prevent such a situation that the ultraviolet radiation starting element 7 is thermally deteriorated and does not emit predetermined ultraviolet radiation.

  In addition, even if the arc tube bulb 51 is broken and the fragments of the members are scattered, the hollow tube 6 is provided around the arc tube 5 to prevent this or reduce the impact. The stress on the outer tube valve 1 can be reduced, and the outer tube valve 1 can be prevented from being damaged, thereby greatly contributing to safety.

  Further, since the lamp L is shielded from the heat radiation of the arc tube 5 by the hollow tube 8 disposed close to the arc tube 5 and surrounding the periphery, the arc tube bulb 51 can be further heated. That is, this temperature rise also raises the temperature of the entire arc tube bulb 51 and the base portions of the inner end electrodes 6A and 6B forming the coldest portion, so that the luminescent metal enclosed in the bulb 51 evaporates. Thus, it is possible to provide a high-pressure metal vapor discharge lamp L having a higher vapor pressure and improved characteristics such as luminous efficiency and color rendering.

  The lamp of the first embodiment is a metal halide lamp having a rated power of 100 W having almost the same configuration as shown in FIG. 1. The T-shaped outer bulb 1 has a wall thickness of about 1 to 3 mm, an outer diameter of about 40 mm, and a sealing portion. The length from the top portion 11 to the top portion 11 is about 115 mm, and the total length including the base 10 is about 140 mm.

  In the arc tube 5 sealed in the outer tube bulb 1, the outer diameter of the bulging portion 52 of the bulb 51 made of alumina having substantially the same structure as shown in FIG. .5mm, the outer diameter of each small-diameter cylindrical portion 53a, 53b is about 2.6mm, the length is about 14.8mm, the total length is about 46.0mm, the inner (space) volume is about 0.6cc, The distance between the tips of the electrodes 2A and 2B is about 7 mm, the inside is filled with about 4.0 mg of Na-Tl-In-Tm halide, about 11.0 mg of mercury, and about 26.7 kPa of argon Ar as a discharge medium. is there.

  The hollow tube 8 surrounding the arc tube 5 has a cylindrical shape made of quartz glass having an outer diameter of about 24 mm, a wall thickness of about 1.0 mm, and a total length of about 34 mm.

  Further, the enhancer 7 constituting the ultraviolet radiation starting element has substantially the same configuration as shown in FIG. 4 and has an outer diameter of about 4 mm, an inner diameter of about 2 mm, an overall length of about 20 mm, and an ultraviolet radiation section 75 having a length of about 10 mm. A lead wire 73 also serving as a sealing wire made of molybdenum wire having an outer diameter of about 0.75 mm is hermetically sealed in a sealing portion 72 at the end of an ultraviolet ray-permeable airtight valve 71 made of cylindrical quartz glass. .

  In addition, an electrode 74 constituting a foil-like internal conductive member made of molybdenum having a width of about 1.5 mm, a thickness of about 30 μm, and a length of about 8 mm is connected in the hermetic valve 71. A lead wire 73 is led out of the valve 71. In addition, a rare gas such as argon is sealed in the hermetic valve 71 at a pressure of about 1300 Pa. In addition, an outer conductive member 76 that also serves as a holding member for a strip-like thin plate made of stainless steel having a thickness of about 0.3 mm is wound around the outer periphery of the airtight valve 71 and connected and fixed to the power supply member 3a.

  As the power supply members 3a and 3b, stainless steel wires having an outer diameter of about 2.0 mm are used. In addition, the pair of support members 4a and 4b that support the arc tube 5, the hollow tube 8 and the enhancer 7 in the outer tube bulb 1 are thin plates having substantially the same outer shape and made of stainless steel or the like with a thickness of about 0.3 mm. It is spider shaped with an outer diameter of about 30 mm punched out by a press and a gap (space) formed between the leg parts, and the ultraviolet radiation part 75 side of the enhancer 7 is located in the hollow tube 8 from this gap. A mounting discharge lamp L was constructed as follows.

  In the discharge lamp L having such a configuration, since the enhancer 7 is disposed in the vicinity of the electrodes 6A and 6B of the arc tube 5, the number of initial electrons in the arc tube 5 is increased at the time of start-up. As a result, the time required for starting the lamp L was shortened.

  In addition, according to the experiments by the present inventors, in a high pressure discharge lamp having a rated power of 20 to 150 W having the same configuration as described above and a total length of the lamp including the base of about 100 to 150 mm, which can be reduced in power consumption, By placing an ultraviolet radiation starting element such as an enhancer close to the electrode of the arc tube, the starting characteristics could be improved.

  Further, in the lamp having the same rating and the same rated power as the discharge lamp of Example 1, the height from the end face of the hollow tube 8 to the top of the enhancer 7 on the ultraviolet radiation portion 75 side, and the inside of the arc tube 5 It was found that preferable starting characteristics can be obtained by regulating the relationship with the height of the electrode 6A up to the tip.

  That is, the height U from the end surface of the hollow tube 8 to the top of the enhancer 7 (ultraviolet radiation part 75 side) and the height from the end surface of the hollow tube 8 to the tip of the electrode 6A adjacent to the enhancer 7 in the arc tube 5 The start-up time was shortened by setting the ratio U / D with respect to the length D in the range of 0 to 1 not including 0.

  FIG. 5 is a graph when this ratio is changed. The horizontal axis indicates the height U from the end face of the hollow tube 8 to the top of the enhancer 7 and the height D from the tip of the adjacent electrode 6A in the arc tube 5. The ratio U / D is compared, and the vertical axis compares the time (seconds) required to start the lamp (from power-on to arc arc generation). When this ratio U / D is smaller than 0, The absence of the enhancer 7 in the hollow tube 8 is not preferable because the amount of ultraviolet irradiation to the electrode 6A is small and a long time is required for starting.

  When the ratio U / D exceeds 1, the start time does not change, and the enhancer 7 shields the emitted light from the arc tube 5 or the enhancer 7 gets too close to the arc tube 5 to increase the temperature. This is not preferable because there is a problem such as causing damage such as leakage in the sealing portion.

  FIG. 6 is a longitudinal sectional view showing an outline of an embodiment of a lighting fixture 9 for store lighting equipped with the high-pressure metal vapor discharge lamp L according to the present invention.

  The lighting fixture (downlight) 9 shown in FIG. 6 has a socket 93 attached to a base 92 provided in the upper part of a housing 91 and has a conical shape made of a metal plate and reflects it on the inner surface. The reflecting shade 94 having a surface is fixed, and the base 10 of the discharge lamp L is mounted on the socket 93, whereby the lamp L is held and electrically connected.

  In this luminaire 9, for example, a casing 91 is attached to a ceiling surface of a department store or the like with the opening side of the reflective shade 94 facing downward, and a power circuit is turned on to turn on a lighting circuit device (not shown), The discharge lamp L is energized through the socket 93.

  Then, when the lamp L in a vertical state with the base 10 side upward (has up) in the reflecting shade 94 is turned on, visible light from the lamp L is reflected by the reflecting surface or directly transmitted through the opening. Then, it is possible to obtain a predetermined illuminance by irradiating a product, a venue, a passage or the like below which is an object to be irradiated.

  Therefore, since the lighting fixture 9 according to the embodiment of the present invention using the high-pressure metal vapor discharge lamp L uses the discharge lamp L with improved starting characteristics, the lamp L can be moved in a shorter time than the conventional fixture. The lighting fixture 9 can be provided with a desired illumination and safety can be improved, so that it is possible to omit the provision of a protective cover member for preventing scattering made of tempered glass or a wire mesh in the opening of the fixture. Can be provided.

  In this embodiment, the casing 91, the base 92, the socket 93, the reflective shade 94, and the like constitute the instrument body. However, if not necessary, some members are omitted or a front cover is included. The instrument body can be configured. Further, the lighting circuit device of the lamp L, the power switch, and the like may be provided in a place different from the instrument body, or may be housed in the housing 91 or the like.

  The present invention is not limited to the above embodiment. For example, as a material for forming the arc tube bulb as a discharge vessel, ceramics made of aluminum oxide (alumina) or the like is used, but yttrium-aluminum- that can satisfy luminescent characteristics, heat resistance, corrosion resistance, electrical insulation, and the like. Even if translucent ceramics such as garnet oxide, yttrium oxide, aluminum nitride, ruby or sapphire are used, or depending on the type of discharge lamp, silicon oxide such as quartz glass, borosilicate glass or aluminosilicate glass may be used. Heat-resistant translucent high silica glass as a main component may be used.

  The arc tube bulb is composed of a single shape such as a cylindrical shape, an oval shape, a spherical shape, or a composite shape. The form of the sealing part formed at the end of the arc tube bulb can be filled with an adhesive in the case of ceramics, shrink-fitted with a disk or cap, or sealed with an adhesive, and in the case of glass An introduction conductor such as a metal foil or a metal wire can be sealed in the valve end portion by crushing sealing or shrink (baking drawing) sealing.

  In addition, the electrodes provided in the arc tube are at least a pair, and the presence or absence of an auxiliary electrode is not questioned. Further, as the discharge medium sealed in the arc tube bulb, mercury, luminescent metal, halogen, rare gas, or the like can be appropriately selected and used according to the lamp type, application, characteristics, and the like.

  The hollow tube can be made of a heat-resistant and light-transmitting material similar to the arc tube bulb, and has a cylindrical shape. The thickness of the hollow tube is in the range of about 1.0 to 3.0 mm, and the hollow tube may be a double tube.

  As a means for increasing the strength of the hollow tube, it is possible to cope by winding a linear or mesh reinforcing body made of inorganic fibers such as heat-resistant ceramics around the outer periphery of the hollow tube. Also, a phosphor film, a light diffusion film, a coating film such as a blocking film that reflects or absorbs ultraviolet rays, or an uneven surface for light diffusion may be formed on the surface of the hollow tube.

  The support member fixed to the power supply member and supporting both ends of the arc tube and the hollow tube surrounding the arc tube is molded into a spider shape or a disc shape with a metal thin plate such as stainless steel or a ceramic plate. It is sufficient that the arc tube or the hollow tube is fixed and locked by the cut and raised portions or the concavo-convex portion, and it has a gap (space portion) rather than completely covering the end surface of the hollow tube in the direction of the arc tube axis. It can emit light and can also be used to install and support ultraviolet radiation starting elements.

  In addition, the support member made of a metal member is used as a power supply member to the electrode in the arc tube or the conductive member of the ultraviolet radiation starting element and is electrically connected to the conductive member of the arc tube bulb or the ultraviolet radiation starting element even when an electric potential is applied. Alternatively, a configuration in which no isolated potential is applied may be used.

  Further, the arc tube may be supported by fixing the bulb end or the externally introduced conductor led out from the end directly to the support member or the power supply member. This can be done by attaching or caulking.

  Further, the starting element that constitutes the ultraviolet radiation source is composed of an enhancer, a glow starter (lighting tube), etc., and a hard glass such as quartz glass or borosilicate glass that transmits at least a part of the wavelength of 200 nm to 460 nm, ultraviolet light An ultraviolet ray permeable bulb such as permeable soft glass or ceramic is used, and a discharge medium such as argon gas or argon gas and mercury and an internal conductive member are sealed in the bulb, and ultraviolet rays are emitted during glow discharge. To be released.

  As the internal conductive member of the enhancer, a metal such as molybdenum or tungsten having electrical conductivity and heat resistance, or tantalum having a getter function for absorbing an impurity gas inside can be used. In addition, the shape and form of the conductive member is rod-shaped, foil-shaped, coil-shaped, etc., and even if it is connected to the introduction line penetrating the sealing portion or does not have the introduction line, it is dielectrically connected to the outside of the container It may be done.

  The external conductive member is a wire or thin plate (foil) made of a metal such as iron-nickel alloy, iron-nickel-chromium alloy, nickel, copper or niobium, and the outer peripheral surface of the bulb of the ultraviolet radiation starting element. It is installed so as to be wound around and is capacitively coupled to the internal conductive member.

  The arrangement of the ultraviolet radiation starting element is provided close to and parallel to the arc tube in the above embodiment, but may be provided inclined or substantially orthogonal to the arc tube. Further, the arrangement of the ultraviolet radiation starting element is provided in the vicinity of the support member 4b on the neck portion 12 side in FIG. 1, but may be provided in the vicinity of the support member 4a on the top portion 11 side or both the upper and lower support members 4a, You may provide in the multiple places of the vicinity of 4b.

  In short, it is only necessary that the ultraviolet radiation portion is in close proximity to the electrode in the arc tube. For example, in the case of an enhancer, the bulb sealing portion is farther from the electrode in the arc tube, and in the case of a glow starter, the emitter material is often attached. It is preferable to dispose the top side away.

  The outer tube bulb is made of hard glass such as quartz glass, borosilicate glass or aluminosilicate glass, or soft glass such as soda lime glass, and the shape thereof is A type, A type, AP type, B type, BT type, etc. What was formed in ED form etc. can be used.

  The inside of the outer tube valve is an inert gas or nitrogen gas atmosphere or a vacuum atmosphere. In other words, inert gas or nitrogen gas is sealed in the outer tube bulb at a low pressure or in a vacuum atmosphere to prevent oxidation of the arc tube components, support members, and stem components that become hot during lighting, and to prevent the lamp from The restart time can be shortened, and it is possible to prevent rupture when the outer tube valve is damaged.

  The high-pressure metal vapor discharge lamp to which the present invention can be applied has, for example, a multi-tube structure such as a double tube in which an arc tube is sealed in an outer bulb in a metal halide lamp, a short arc metal halide lamp, a high-pressure mercury lamp, or the like. . Moreover, the lighting posture of the discharge lamp may be an inclined posture as well as horizontal and vertical.

  Furthermore, the lighting fixture to which the present invention can be applied may have members such as a reflecting mirror, a translucent cover and a lens, and the lighting circuit device may be installed inside or outside the fixture. May be.

  Furthermore, the luminaire is a broad concept including any fixture that uses the light emission of a high-pressure discharge lamp for any purpose. For example, it is preferable to apply to lighting for department stores, stores, theaters, halls, underground malls, plazas, offices and factories as well as headlights for mobile objects, light sources for optical fibers, image projection, photochemistry, fingerprint discrimination, etc. Starting characteristics and emission characteristics can be obtained.

It is a schematic front view which shows embodiment of the metal vapor | steam high-pressure discharge lamp (metal halide lamp) of this invention. It is sectional drawing which shows the outline of the cut surface along the arrow aa line in FIG. It is an expanded sectional front view which shows the arc tube part arrange | positioned in the outer tube | bulb bulb | bulb in FIG. It is an enlarged front view which shows the ultraviolet radiation start element (enhancer) arrange | positioned in the outer tube | pipe valve | bulb in FIG. The horizontal axis is the ratio U / D between the height U from the end face of the hollow tube to the top of the enhancer and the height D to the adjacent electrode in the arc tube, and the vertical axis is the time (seconds) required to start the lamp. It is the graph which contrasted. It is a front view which shows the outline of the lighting fixture equipped with the metal vapor | steam high pressure discharge lamp (metal halide lamp) shown to embodiment of this invention.

Explanation of symbols

L: Metal vapor high pressure discharge lamp (metal halide lamp)
1: Outer tube bulb 3a, 3b: Power feeding member 4a, 4b: Support member 5: Arc tube 51: Arc tube bulb (discharge vessel)
6A, 6B: Electrode 63: Introducing conductor 7: Ultraviolet radiation starting element (enhancer)
8: Heat-resistant translucent hollow tube 9: Lighting equipment

Claims (5)

An arc tube in which a pair of electrodes are sealed in a heat-resistant translucent arc tube bulb via an introduction conductor and a discharge medium is sealed;
A cylindrical hollow tube made of a heat-resistant translucent member disposed so as to surround the arc tube;
A support member for supporting both ends of the arc tube and the hollow tube;
A power supply member connected to the introduction conductor of the arc tube;
An ultraviolet radiation starting element supported by the support member or the power supply member and disposed so as to at least partially face the hollow tube;
An outer bulb containing the arc tube, hollow tube, ultraviolet radiation starting element, support member and power supply member;
A high-pressure metal vapor discharge lamp comprising:   The total length of the discharge lamp is 150 mm or less and the length U from the end surface of the hollow tube to the tip of the ultraviolet radiation starting element facing inward, and from the end surface of the hollow tube on the side where the ultraviolet radiation starting element is disposed 2. The high-pressure metal vapor discharge lamp according to claim 1, wherein the relationship with the length D to the tip of the electrode in the arc tube is 0 <U / D ≦ 1.   3. The high-pressure metal vapor discharge lamp according to claim 1, wherein the ultraviolet radiation starting element is an enhancer or a glow starter.   The high-pressure metal vapor discharge lamp according to any one of claims 1 to 3, wherein the hollow tube has a length that covers at least the inner end portion of the arc tube bulb. An instrument body;
A high-pressure metal vapor discharge lamp according to any one of claims 1 to 4 disposed in the appliance body;
A lighting circuit device connected to the high pressure metal vapor discharge lamp;
The lighting fixture characterized by comprising.

Images