JP2011009090A - Discharge lamp device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge lamp device provided with an ultraviolet radiation auxiliary light source capable of starting at 2 kV or less in a double tube type discharge lamp incorporating a reflecting mirror.
In a discharge lamp apparatus comprising a discharge lamp having a light emitting tube made of a translucent ceramic container in an outer tube and having a pair of electrodes opposed to each other in the tube axis direction in the light emitting tube, and an ultraviolet radiation auxiliary light source. The ultraviolet radiation auxiliary light source is hermetically sealed and includes a metal foil member in a quartz glass container filled with a rare gas. The metal foil member has a longitudinal direction and a short direction, and a creeping length in the short direction is A discharge lamp device having a length of 90% or more of the inner diameter of the quartz glass container and having a U-shaped or V-shaped cross-section in a direction perpendicular to the tube axis of the metal foil member.
[Selection] Figure 2

Description

  The present invention relates to a discharge lamp device, and more particularly to a discharge lamp device including a double tube type discharge lamp with a reflecting mirror having an ultraviolet radiation auxiliary light source.

  Recently, metal halide lamps are generally used in a wide range of fields such as outdoor lighting and store lighting. The structure of metal halide lamps for lighting is a double discharge lamp structure, and the inner tube becomes hot, so quartz glass and ceramic materials are used. The arc tube, which is the inner tube, uses argon. And mercury, and prescribed metal halides are enclosed. Further, the outer tube is for protecting the inner tube at a high temperature, and is evacuated for the purpose of preventing oxidation of the metal structure in the outer tube and increasing the luminous efficiency of the inner tube. These lamps generally apply a high voltage between the electrodes in the arc tube at start-up to cause dielectric breakdown in the discharge medium in the discharge tube, and induce glow discharge and arc discharge by using the generated plasma electrons as seeds. There is a need to.

The voltage for causing dielectric breakdown increases in a lamp after being chilled or after being lit for a long time, so that the lighting performance is deteriorated. As a method for causing dielectric breakdown and improving lighting performance, there is a technique disclosed in Japanese Patent Laid-Open No. 2001-151006. This publication discloses a discharge lamp in which an arc tube and an ultraviolet radiation auxiliary light source (ultraviolet light source) are arranged in a double tube outer tube.
FIG. 5 shows an enlarged view of the ultraviolet light source (corresponding to the ultraviolet radiation auxiliary light source of the present invention). The ultraviolet ray source 20 includes a flat foil member 22 having a width of about 1.5 mm, a length of about 8 mm, and a thickness of about 30 μm disposed in an airtight container 21 made of quartz glass having a substantially cylindrical shape. The foil member is a lead wire. 23, and the outer conductive member 24 is spiraled around the outside of the hermetic container 21 approximately four times, and is wound only around the cavity 21a in the hermetic container 21, and the lead wire 23 and the outer conductive member 24 are connected to each other. The external lead wires 25a and 25b led out from the sealing portion (not shown) of the arc tube (not shown) are connected.

  However, according to the description of Japanese Patent Application Laid-Open No. 2001-151006, there is a case where the light is not turned on when the pulse voltage is lower than 2.3 kV. In general lighting applications, this type of discharge lamp is generally used by incorporating it in a reflector. In this case, since external light is blocked, the starting probability is higher than that of a lamp without a reflector. Therefore, a starting voltage of 2 kV or less is desired. For that purpose, if considering the starting voltage of the lamp unit, it is necessary to further lower it from 1.8 kV. In addition, on the other hand, the ultraviolet radiation auxiliary light source has to be accommodated in a narrow outer tube because of the demand for downsizing of the luminaire, and the size of the ultraviolet radiation auxiliary light source is limited.

JP 2001-151006 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a discharge lamp device in which an ultraviolet radiation auxiliary light source (ultraviolet light source) that can be started at 2 kV or lower in a double-tube discharge lamp with a built-in reflector is provided. .

  In order to solve the above-mentioned problem, the invention according to claim 1 is a discharge lamp comprising a light-emitting tube made of a translucent ceramic container in an outer tube, and having a pair of electrodes facing each other in the tube axis direction in the light-emitting tube. And an ultraviolet radiation auxiliary light source, the ultraviolet radiation auxiliary light source is hermetically sealed, a cylindrical quartz glass container sealed with a rare gas, and one side exposed in the container, and the other is exposed to the other. A metal foil member having an external lead connected to the side thereof, and a linear outer conductor wound around the outer surface of the quartz glass container. The external lead and the linear outer conductor are each of the pair of electrodes. The metal foil member has a longitudinal direction and a short direction, and a creeping length in the short direction has a length of 90% or more of an inner diameter of the quartz glass container, Located in the quartz glass container Perpendicular cross section to the tube axis of the metal foil member is one which the discharge lamp device, characterized in that has a U-shape or V-shape.

  According to a second aspect of the present invention, the quartz glass container includes a hollow portion and a seal portion, and the linear outer conductor forms a densely wound portion of a plurality of turns in each of the hollow portion and the seal portion. The discharge lamp device according to claim 1 is provided.

  According to the first aspect of the present invention, an ultraviolet radiation auxiliary light source (ultraviolet light source) that can be started at a starting voltage of 2 kV or less is disposed in the double tube type discharge lamp incorporated in the reflecting mirror. A discharge lamp device can be obtained.

  According to the second aspect of the present invention, since the linear outer conductor forms a densely wound portion having a plurality of turns in each of the hollow portion and the seal portion, between the metal foil member and the linear outer conductor. Since the electrostatic capacity of the battery further increases, the starting voltage can be further reduced.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram of the double tube | pipe discharge lamp apparatus with a reflecting mirror which is embodiment of this invention is shown. The whole block diagram of a double tube type discharge lamp is shown. An enlarged view of an ultraviolet radiation auxiliary light source is shown. The example of a shape of the metal foil part of an ultraviolet radiation auxiliary light source is shown. 1 shows an enlarged view of a prior art UV source. An explanatory view of an evaluation experiment is shown. The table of evaluation results is shown. The emission spectrum figure of the test light source for a measurement equivalent to an ultraviolet radiation auxiliary light source is shown.

FIG. 1 shows an overall configuration diagram of a double-tube discharge lamp device 1 with a reflector as an embodiment of the present invention, and FIG. 2 shows an overall configuration diagram of a single unit of a double-tube discharge lamp 5.
In FIG. 1, a double-tube discharge lamp 5 is fixed to a lamp base 3 on a neck 2 a of a reflecting mirror 2, and a base 4 is attached to the lamp base 3. The reflecting mirror 2 and the lamp base 3 are shown in cross section.

The discharge lamp 5 is an inner tube having a pair of electrodes 8a and 8b made of tungsten or the like opposed to the outer tube 6 made of quartz glass in the tube axis direction, for example, translucent ceramic such as polycrystalline alumina or YAG. An arc tube 7 made of a container is disposed, and an ultraviolet radiation auxiliary light source 9 is provided between the outer tube 6 and the arc tube 7.
The outer tube 6 is evacuated, and although not shown, a getter member that adsorbs an impure gas may be disposed in the outer tube 6.

  In FIG. 2, lamp leads 16 a and 16 b protruding from both ends of the arc tube 7 of the discharge lamp 5 are connected to power supply members 17 a and 17 b disposed in the outer tube 6, respectively. The power feeding members 17a and 17b are connected to the molybdenum metal foils 18a and 18b in the outer tube seal portion 6a, and the molybdenum metal foils 18a and 18b are connected to the external power feeding members 19a and 19b, respectively, to be fed.

  This will be described with reference to FIGS. The ultraviolet radiation auxiliary light source 9 is hermetically sealed, a quartz glass container 13 filled with a rare gas such as argon or xenon, and a metal foil having one side exposed in the container and an external lead 10 connected to the other side. A member 11 and a linear outer conductor 12 wound around the outer surface of the quartz glass container 13 are provided. The external lead 10 and the linear outer conductor 12 are provided with lamp leads 16 a and 16 b protruding from both ends of the arc tube 7. The power supply members 17a and 17b arranged in the outer tube 6 in parallel are connected.

  FIG. 3 shows an enlarged view of the ultraviolet radiation auxiliary light source 9. FIG. 3A is a front view, and FIG. 3B is a side view. The ultraviolet radiation auxiliary light source 9 includes a hollow portion 13a and a seal portion 13b. The metal foil member 11 has a longitudinal direction and a transverse direction, and the creeping length in the transverse direction is 90% or more of the inner diameter of the quartz glass container 13. The cross-sectional shape in the direction perpendicular to the tube axis of the metal foil member 11 is U-shaped.

  The creeping length in the short direction is 90% or more of the inner diameter of the quartz glass container 13. The reason why the length is 90% or more of the inner diameter is that the width (the length in the short direction) that can be inserted into a quartz glass container with high productivity in the case of a flat metal foil member that is a conventional technology is quartz. It is 90% of the inner diameter of the glass container. By making it U-shaped, it becomes possible to insert a metal foil member with a length of 90% or more, and when it is 90% or more, a conventional planar metal foil member This is because the lighting startability is superior to the above case. The quartz glass container 13 is filled with several kPa of rare gas argon. Outside the quartz glass container 13, the linear outer conductor 12 is densely wound with a plurality of turns on the cavity portion 13 a and the seal portion 13 b.

To illustrate specific materials and specific dimensions, the quartz glass container of the ultraviolet radiation auxiliary light source has a total length of 14 mm, an outer diameter of 3 mm, an inner diameter of 1.6 mm, and the metal foil member 11 is made of molybdenum and has a thickness of 20 μm. The creeping length in the short direction of the member is 1.5 mm, the length in the longitudinal direction is 9 mm, the linear outer conductor 12 is made of molybdenum, the wire diameter is 0.5 mm, and the outer periphery of the hollow portion 13 a Ten turns are wound around the outer periphery of the seal portion 13b for 20 turns.
The larger the number of turns, the better, but it depends on the size of the quartz glass container 13. However, by tightly winding the linear outer conductor 12 wound around the outer periphery of the cavity 13a and the outer periphery of the seal portion 13b, the linear outer conductor 12 is firmly adhered to the quartz glass container 13 by tightening. Compared with the case where the linear outer conductor 12 is loosely wound around the quartz glass container 13, the dielectric barrier discharge is more likely to occur due to the high frequency high voltage applied between the metal foil member 11 in the cavity. The bundling conductor 12a in FIG. 3 indicates that the linear outer conductor 12 is bound and tightened to one.

  The seal portion 13b may be a shrink seal instead of the pinch seal. In the case of the shrink seal, the cross-sectional shape in the direction perpendicular to the tube axis of the metal foil member can be kept U-shaped. The creeping length in the short direction of the metal foil member can be 100% or more of the inner diameter of the quartz glass container. This is because the metal foil member is not pressed flat at the seal portion, and thus a metal foil member having a creeping length in the short direction that is equal to or larger than the inner diameter of the cavity portion can be accommodated.

FIG. 4 shows a view in which only the metal foil member 11 and the external lead 10 are taken out. 4A shows a state in which the external lead 10 is connected to the U-shaped metal foil member 11, and FIG. 4B shows a form after the pinch seal. Since pinch sealing is performed, the cross-sectional shape perpendicular to the tube axis of the metal foil member 11 located in the quartz glass container 13 is U-shaped, and gradually becomes flat as it approaches the seal portion.
FIG. 4C shows a state in which the external lead 10 is connected to the V-shaped metal foil member 11, and FIG. 4D shows a form after the pinch seal.

FIG. 6 and FIG. 7 show a method and results of an experiment confirming the effect of the present invention.
In general lighting applications, this type of discharge lamp is generally used by incorporating it in a reflector. In this case, since external light is blocked, the starting probability is higher than that of a lamp without a reflector. Therefore, a starting voltage of 2 kV or less is desired. For that purpose, if considering the starting voltage of the lamp unit, it is necessary to further lower it from 1.8 kV.

  Reasons that lamp operating voltage may increase due to wear of the electrode of the lamp itself or blackening of the arc tube during the product life of the lamp or ballast, or problems such as high-pressure deterioration may occur due to deterioration of the electronic components of the ballast itself. Thus, it is difficult to turn on the light with the reflector. Therefore, in order to light at a low high voltage of 2 kV even in the form with a reflector, if the ultraviolet radiation auxiliary light source is discharged alone at 1.3 kV or less, even if it is incorporated into the reflector and used, it is sufficiently below 2 kV. The inventors considered that a starting voltage of 2 can be secured. Therefore, the following starting voltage measurement experiment was conducted.

<Experimental conditions>
As a test light source for measurement of an ultraviolet radiation auxiliary light source, a flat member having a foil member shape in the prior art, a U-shaped foil according to the present invention (Example 1), and a V-shaped foil (Example 2) Twenty test light sources for measuring the three types of foils each having three types of foil members were prepared. A part of the foil member was sealed so that the area exposed to the cavity of the quartz glass container was the same.

The foil width is 1.2 mm in the short direction in the flat foil in the conventional example. The length of the cavity in the longitudinal direction was 5.5 mm, and the area was 6.6 mm ² . In the U-shaped foil (Example 1) and the V-shaped foil (Example 2), the creeping length in the short direction is 1.5 mm in order to make the area located in the cavity the same as the conventional example. And 90% of the inner diameter of the cavity. The length of the cavity in the longitudinal direction was 4.4 mm, and the area was 6.6 mm ² . That is, the area of the foil member was made the same in the conventional example, Example 1, and Example 2. The creepage length is the total length of a length and b length if it is V-shaped in FIG. In the case of a U-shape, the length is along the U-shape. The linear outer conductor was wound 20 turns in the cavity and 10 turns in the seal part. A lead wire is welded to the outer end of the foil member and protrudes from the seal portion.

  The container of the measurement test light source is made of quartz glass, the foil member is made of molybdenum having a thickness of 20 μm, and the linear outer conductor is made of molybdenum having a diameter of 0.2 mm. The cavity is filled with 5 kPa of argon.

<Manufacturing method>
An external lead rod Φ0.5 length 13 mm is welded to a molybdenum metal foil (width 1.5 mm × length 9 mm × thickness 20 μm). The welding margin at this time is 1 mm to 2 mm.
Molybdenum metal foil welded to an external lead is made U-shaped (here, U-shape is, for example, curvature R = 0.8 to 1.5 mm) or V-shaped (for example, the bending angle is angle = 100 °). ) The shape of the foil is deformed by pressing with a jig that has been grooved. The U-shaped metal foil with external lead is inserted into a quartz glass container having an outer diameter of 3 mm and an inner diameter of 1.6 mm, and one side is sealed with a pinch seal or a shrink seal. At this time, the sealing is performed such that the metal foil protruding into the quartz glass container cavity is 4.4 mm.

  Next, exhaust and vacuum heat treatment are performed from the side opposite to the side sealed by the pinch seal or shrink seal, and then a rare gas such as argon is sealed. At this time, as a gas pressure, 2-10 kPa is sealed and sealed with a burner or the like. A linear outer conductor made of molybdenum and having a diameter of 0.2 mm is attached to an ultraviolet radiation auxiliary light source filled with argon.

  The linear outer conductor has a shape wound about 10 to 20 turns spirally around the outer periphery of the cavity of the ultraviolet radiation auxiliary light source. Close winding is desirable. Twist the spiral wound ends several times to prevent the linear outer conductor from loosening or coming off due to vibration or thermal expansion changes. Further, if the linear outer conductor is wound around the outer periphery of the sealing portion of the ultraviolet radiation auxiliary light source and is installed by being twisted in the same manner as the hollow portion, it is more firmly fixed.

<Lighting start test>
As shown in FIG. 6, the linear external conductor 26a of the measurement test light source 26 and the external lead 26b protruding from the seal portion are respectively connected to the ballast 27, the switch 28 is turned on, the high frequency 300 kHz, the high voltage high A high voltage of 1.3 kV was applied. To check the lighting, place a test light source for measurement in the dark, apply a 50W ballast made by USHIO LIGHTING, and adjust the length of the secondary wire so that the high voltage is 1.3kV. went. FIG. 8 shows an emission spectrum of the measurement test light source 26 equivalent to the ultraviolet radiation auxiliary light source. The lighting was confirmed by visually observing visible light on the long wavelength side of light emission in the region of about 300 nm to 420 nm with argon.

  The experimental results are shown in FIG. 7. As for the auxiliary light source of flat foil (flat foil), only 10 out of 20 lights up when a high voltage of 1.3 kV was applied. However, with the auxiliary light source of the U-shaped foil and the auxiliary light source of the V-shaped foil according to the present invention, all 20 auxiliary light sources were lit without any trouble. And when the auxiliary light source of the U-shaped foil which concerns on this invention was equipped in the discharge lamp with a reflecting mirror, and the starting voltage was measured, the starting in 2 kV or less was confirmed.

  From this experimental result, when the shape of the metal foil member constituting the auxiliary light source is compared with a foil of the same area, it is lower when the U-shaped or V-shaped foil is used than the flat-shaped foil. It turned out to be lit with voltage.

DESCRIPTION OF SYMBOLS 1 Double tube | pipe discharge lamp apparatus with a reflecting mirror 2 Reflecting mirror 2a Neck part 3 Lamp base 4 Base 5 Discharge lamp 6 Outer tube 7 Light emission tube 8a, 8b Electrode 9 Ultraviolet radiation auxiliary light source 10 External lead 11 Metal foil member 12 Linear External conductor 13 Quartz glass container 13a Cavity part 13b Seal parts 16a and 16b Lamp leads 17a and 17b Power supply materials 18a and 18b Molybdenum metal foils 19a and 19b External power supply member 20 Ultraviolet source 21 Airtight container 21a Cavity part 22 Flat foil member 23 Lead Wire 24 External conductive member 25a, 25b External lead wire 26 Test light source 26a External conductive member 26b External lead 27 Ballast 28 Switch

Claims (2)

In the outer tube, a discharge lamp device comprising a light emitting tube made of a translucent ceramic container, a discharge lamp having a pair of electrodes opposed to each other in the tube axis direction in the light emitting tube, and an ultraviolet radiation auxiliary light source,
The ultraviolet radiation auxiliary light source is hermetically sealed, a cylindrical quartz glass container sealed with a rare gas, a metal foil member having one side exposed in the container and an external lead connected to the other side, A linear outer conductor wound around the outer surface of the quartz glass container, and the external lead and the linear outer conductor are each electrically connected to each of the pair of electrodes,
The metal foil member has a longitudinal direction and a transverse direction, and a creeping length in the transverse direction is 90% or more of the inner diameter of the quartz glass container, and is located in the quartz glass container. A discharge lamp device characterized in that a cross-sectional shape of the metal foil member in a direction perpendicular to the tube axis is U-shaped or V-shaped. The quartz glass container includes a hollow portion and a seal portion, and the linear outer conductor forms a densely wound portion of a plurality of turns in each of the hollow portion and the seal portion. 2. The discharge lamp device according to 1.

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