JP2007157513A - Structure of sealed part of short arc type discharge lamp, and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the reliability and the manufacturing efficiency of the double-sealed structure of a short arc type discharge lamp. <P>SOLUTION: A mount part 19 is constituted by assembling an electrode (an anode 2 or a cathode 3), an electrode supporting rod 4, an internal glass tube 6, an internal metal ring 14, a lead rod 5, an external metal ring 15, a plurality of metal foils 8, an external glass tube 7, and a glass rod 18. The mount part 19 in inserted into an outside sealed tube 11 and an inside sealed tube 10, and welded. At that time, the internal glass tube 6 and the outside sealed tube 11 are welded so that the inside end 16 of the inside sealed tube 10 is not exposed to a discharging space S. Since the end to be welded becomes one part, the reliability is improved, the double-sealed tube can be sealed at one time, and a working time can be shortened. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sealing structure of a short arc discharge lamp, and more particularly to a structure in a sealing tube of a short arc discharge lamp used in the field of manufacturing semiconductors and liquid crystals.

  A short arc type discharge lamp having a single sealing structure has a structure as shown in FIG. In a short arc type discharge lamp used as a light source in the field of manufacturing semiconductors and liquid crystals, an electrode is supported by a sealing portion, and an arc tube is kept airtight. The structure of the sealing portion of the short arc type discharge lamp having a single sealing structure will be described with reference to FIG.

  Between the electrode support rod 4 that supports the anode 2 and the sealing tube 51, there is an internal glass tube 6 that holds the electrode support rod 4. The electrode support bar 4 is welded to the inner metal ring 14. The inner metal ring 14 is interposed between the inner glass tube 6 and the glass rod 18. On the circumferential surface of the inner metal ring 14, a plurality of metal foils 8 having a thickness of 1 mm or less are welded. A metal foil (not shown) is further wound on the circumferential surface. The plurality of metal foils 8 are disposed between the glass rod 18 and the sealing tube 51 so as to be separated from each other in the circumferential direction. The plurality of metal foils 8 are electrically connected to each other via an inner metal ring 14 welded to them.

  The plurality of metal foils 8 are welded to the outer metal ring 15. A metal foil (not shown) is further wound on the circumferential surface. The outer metal ring 15 is interposed between the outer glass tube 7 and the glass rod 18. A lead bar 5 is welded to the outer metal ring 15, and power is supplied from the lead bar 5. A series of metallic parts for supplying electric power from the lead bar 5 to the anode 2 inside the discharge lamp and parts composed of glass parts for holding them are collectively referred to as a mount part. A portion where the mount component is welded to the sealing tube is referred to as a sealing portion. Such a sealing portion is closely related to the strength and life of the discharge lamp.

  The metal foil 8 is sandwiched between the glass rod 18 and the sealing tube 51, and is heated and welded by a burner or the like, thereby sealing the inside of the discharge lamp and the outside. In FIG. 13, the length from the discharge space side end face of the inner glass tube 6 to the tip end face of the anode 2 is A3. When sealing, if the welding between the sealing tube 51 and the internal glass tube 6 is insufficient, a crack is generated from the welding end portion 56 and causes rupture. There is a need. Further, when the arc tube 1 is deformed by heat from a burner or the like when sealing, the performance as a discharge lamp is significantly lowered. Therefore, in order to prevent deformation of the arc tube 1 while performing sufficient welding at the time of sealing, the welding end portion 56 needs to be separated from the arc tube 1 to some extent. Therefore, the length A3 from the discharge space side end surface of the inner glass tube 6 to the tip end surface of the anode 2 needs a certain distance.

  On the other hand, in order to improve the production efficiency in the field of manufacturing semiconductors and liquid crystals, the power of short arc discharge lamps is increasing. When the discharge lamp increases in power, the anode 2 becomes larger and heavier. Since it has a cantilever structure in which the electrode is held by the internal glass tube 6 via the electrode support bar 4, a large force is applied from the electrode support bar 4 to the internal metal ring 14 and the like. For this reason, a new problem has arisen such that a great stress is applied to the metal foil 8 at the time of manufacturing the lamp and the sealing portion is damaged. As a countermeasure, it is effective to make the sealing portion have a double sealing structure. In the double sealing structure, since a great deal of stress is not applied to the metal foil 8 at the time of manufacturing the lamp, it is possible to solve the problem that the metal foil 8 is broken. In addition, even if the electrode becomes large and very heavy, the mounting parts can be accurately welded to the sealing tube, the mechanical strength of the sealing part is increased, and the risk of breakage during lamp manufacturing and transportation is reduced. . Below, the prior art of the double sealing structure of a short arc type discharge lamp is demonstrated.

  A conventional double arc structure short arc type discharge lamp proposed by the present applicant in Patent Document 1 will be described with reference to FIGS. FIG. 14 is a cross-sectional view of a sealed portion of a short arc type discharge lamp having a conventional double sealed structure. As shown in FIG. 14, there is an arc tube 1 that forms a discharge space, and a pair of electrodes (anode 2 and cathode 3) are disposed opposite to each other in the arc tube 1. A2 is the length from the discharge space side end face of the inner glass tube 6 to the tip end face of the anode 2.

  A discharge lamp as shown in FIG. 14 is usually shipped as a product with a base (base) fixed with an adhesive or the like so as to wrap around the outer metal ring of the sealing portion. The discharge lamp is attached to a lighting device via a base (base) and lights up. During lighting, the light emitted from the discharge lamp is reflected by an elliptical mirror to irradiate a desired place. Part of the light reflected from the elliptical mirror irradiates the base and heats the base. When the size of the electrode increases with the increase in power of the discharge lamp, the strength of the sealing portion is increased in order to hold the electrode. In order to increase the strength of the sealing portion, the outer diameter of the sealing portion is increased, and the inner diameter of the die into which the sealing portion is inserted is increased.

  FIG. 15 is an enlarged cross-sectional view of a sealing portion of a short arc type discharge lamp having a conventional double sealing structure. Outer sealing tubes 11 are connected to both ends of the arc tube 1 forming the discharge space. The inner sealing tube 50 is welded coaxially inside the outer sealing tube 11. The mounting component 19 of the short arc type discharge lamp includes an electrode support rod 4 connected to the electrode, an internal glass tube 6 holding the electrode support rod 4, and an internal metal ring 14 electrically connected to the electrode support rod 4. The metal foil 8 welded to the inner metal ring 14, the glass rod 18 on which the metal foil 8 is disposed on the outer peripheral surface, and the outer metal disposed on the outer side of the glass rod 18 and electrically connected to the metal foil 8 The ring 15 is composed of a lead bar 5 connected to the external metal ring 15 and fed from the outside, and an external glass tube 7 holding the lead bar 5. In this discharge lamp, a sealing body in which a metal foil 8 is welded by an inner sealing tube 50 having an inner diameter larger than the outer diameter of the mount component 19 is disposed in the outer sealing tube 11. It has a structure in which the tube 11 is welded.

  FIG. 16 is a partially enlarged sectional view of a sealing portion of a short arc type discharge lamp having a conventional double sealing structure. In FIG. 16, the outer welding end 55 is the end of the welding portion between the inner sealing tube 50 and the outer sealing tube 11 on the discharge space side. The inner welding end portion 54 is a terminal end on the discharge space side of the welding portion between the inner glass tube 6 and the inner sealing tube 50. B1 is the length in the axial direction in which the inner sealing tube 50 is exposed to the discharge space.

  The welded portion between the inner sealing tube 50 and the inner glass tube 6 needs to be sufficiently heated to be adapted. The reason is that if welding between the inner sealing tube 50 and the inner glass tube 6 is insufficient, a crack is generated from the inner welding end portion 54 and becomes a starting point of rupture when the lamp is turned on. Furthermore, the welded portion between the inner sealing tube 50 and the outer sealing tube 11 also needs to be sufficiently heated to become familiar. The reason is that if the welding between the inner sealing tube 50 and the outer sealing tube 11 is insufficient, a crack is generated from the outer welding end portion 55 and becomes a starting point of rupture when the lamp is turned on.

  The manufacturing method of this double sealing structure will be described with reference to FIGS. FIG. 17A is a view showing a state in which the mount component 19 is inserted into the inner sealing tube 60 before welding. The mounting component 19 is inserted into the inner sealing tube 60 before welding, and the inner sealing tube 60 before welding is heated to a negative pressure by a burner or the like, and the inner sealing tube 60 and mounting component before welding are mounted. 19 is welded. The inner sealing tube 60 before welding is heated to be reduced in diameter by a burner or the like, and is welded to at least the end of the inner glass tube 6 on the electrode side. The inner sealing tube welded to the inner glass tube 6 is cut at a desired position.

  FIG. 17B is a view showing a state in which the mount component 19 obtained by cutting the inner sealing tube 50 at a desired position is inserted into the outer sealing tube 21 before welding. In FIG. 17 (c), the mount component 19 obtained by cutting the inner sealing tube 50 at a desired position is inserted into the outer sealing tube 21 before welding, and the anode 2 is placed in the desired position in the discharge space S. Shows the state of arrangement. The inside of the outer sealing tube 21 (in the discharge space) before welding is in a negative pressure state and heated by a burner or the like to weld the outer sealing tube 21 and the inner sealing tube 50 before welding. Sealing is similarly performed on the cathode 3 facing in the discharge space.

  In order for the inner sealing tube 50 to be sufficiently welded to the outer sealing tube 21 before welding, there is an axial length B1 (FIG. 16) where the inner sealing tube 50 is exposed to the discharge space. Preferably it has a length in the range. Therefore, as shown in FIG. 16, the outer welding end 55 and the inner welding end 54 are separated from each other in the axial direction by a length B1. Further, for the same reason as in the single sealing structure, the outer welding end portion 55 is preferably disposed at a distance from the arc tube 1. Therefore, the length A2 (FIG. 14) from the discharge space side end face of the inner glass tube to the tip end face of the anode 2 in the conventional double sealing structure is the same as the length A3 (FIG. 13) in the case of the single sealing structure. In comparison, the length becomes longer by B1. That is, A2≈B1 + A3.

The sealing process in the discharge lamp manufacturing process includes an exhaust process and a welding process. The exhaust process is a process for bringing the inside of the sealed tube into a negative pressure state, and the welding process is a step of reducing the diameter of the sealed tube heated inside by a heat of a burner or the like by a heat such as a burner. Since the single tube sealing structure has one sealing tube, the sealing step is performed once. In contrast, as shown in FIG. 17, the sealing process of the conventional double sealing structure includes a sealing process of the inner sealing tube (FIG. 17 (a)) and a sealing process of the outer sealing tube (FIG. 17). In (b)), the sealing step is required twice.
Japanese Patent Application No. 2005-279313 Specification

  However, the conventional double sealing structure has the following problems. The inner glass tube is disposed at a position farther from the electrode than in the case of the single sealing structure. Even when an electrode having the same weight is held by an inner glass tube having the same shape via an electrode support rod, a greater stress is applied to the inner glass tube than in the case of a single sealed structure due to the lever principle. For this reason, the internal glass tube is easily broken, and the risk of such breakage becomes more conspicuous due to the increase in size of the electrode accompanying the increase in power of the discharge lamp.

  In the single sealing structure, there is one welding end portion (one circumferential portion) serving as a starting point of rupture when the lamp is turned on. On the other hand, the number of welding end portions, which are the starting points of rupture when the lamp is turned on, increased to two locations (two circumferential portions) at the inner welding end portion and the outer welding end portion. It is necessary to carefully weld the end of the weld in order to avoid increasing the number of causes of rupture and lowering the reliability, and it takes a lot of sealing work and inspection work, and the efficiency of the lamp manufacturing process Becomes worse.

  When the inner sealing tube welded to the inner glass tube is cut at an arbitrary position, minute cuts and cracks are generated on the cut surface of the cut inner sealing tube. If these minute cracks and cracks are left at the end of the inner sealing tube on the discharge space side, it becomes the starting point of rupture when the lamp is lit. In order to eliminate these minute cracks and cracks by heating sufficiently, a lot of sealing work time and inspection work time are required, and the efficiency of the lamp manufacturing process is deteriorated.

  In order to increase the strength of the sealing portion, it is necessary to increase the outer diameter of the sealing portion. When the outer diameter of the base increases, the area where the light reflected by the elliptical mirror hits the base when attached to the lighting device increases. As a result, the temperature of the base becomes abnormally high, causing lamp damage. As a countermeasure, if the lamp base has a structure with high cooling efficiency, the cost of the lamp increases. Further, if a mechanism for strengthening the cooling of the base is attached to the lighting device, the running cost increases. In order to increase the strength of the sealing part, it is necessary to increase the outer diameter of the sealing part, but in order to prevent overheating of the base, it is necessary to reduce the outer diameter of the sealing part. This conflicting condition cannot be met.

  Compared with the case of a single sealing structure, the number of sealing steps is increased and the production efficiency is low. In addition, many facilities are required to obtain the same number of production. When trying to seal the inner sealing tube and the outer sealing tube at a time, the inner sealing tube moves in the axial direction, so that it is impossible to seal at a time. For these reasons, the cost of the lamp is high.

  An object of the present invention is to solve the above-mentioned conventional problems and to improve the reliability and manufacturing efficiency of the double sealed structure of a short arc type discharge lamp.

  In order to solve the above problems, in the present invention, a glass arc tube, a glass outer seal tube connected to the arc tube, and an inner seal coaxially welded inside the outer seal tube. A stop tube, a pair of electrodes sealed in the arc tube, a metal electrode support rod supporting the electrode, an internal metal ring electrically connected to the electrode, and a lead rod for supplying power to the electrode An outer metal ring electrically connected to the lead bar, an inner metal ring and a plurality of metal foils electrically connected to the outer metal ring, an outer glass tube supporting the lead bar, and a lead bar Sealing part of a short arc type discharge lamp having a double sealing structure comprising a glass rod supporting an inner metal ring, an outer metal ring, an electrode supporting rod and a metal foil, and an inner glass tube supporting the electrode supporting rod. The end on the discharge space side of the inner sealing tube of the structure Are arranged in an intermediate portion of the glass tube, it has a configuration which is welded wrapped in an inner glass tube and the outer sealing tube.

  Further, the internal glass tube is a different-diameter internal glass tube having a large diameter portion and a small diameter portion, the intermediate portion is an inclined portion between the small diameter portion and the large diameter portion, and the taper angle R of the inclined portion is 0 ° <R ≦ 90 ° with respect to the central axis of the glass tube. The outer diameter of the outer glass tube, the outer metal ring, the glass rod, and the inner metal ring were all equal to the outer diameter of the small diameter portion of the inner glass tube. The inner sealing tube was an inner sealing tube in which a plurality of partial inner sealing tubes having different types of outer diameters and different outer diameters were integrated in series in the axial direction. Of the inner sealing tube, the outer diameter of the portion surrounding the outer metal ring was made smaller than the outer diameter of the portion surrounding the inner metal ring. A fixing ring was provided on the outer side in the axial direction of the outer glass tube so that the outer end of the inner sealing tube was in contact with the fixing ring.

  Further, a manufacturing method of a short arc type discharge lamp includes an electrode, a metal electrode support rod that supports the electrode, an internal metal ring that is electrically connected to the electrode, a lead rod that supplies power to the electrode, An outer metal ring electrically connected to the lead bar, an inner metal ring and a plurality of metal foils electrically connected to the outer metal ring, an outer glass tube supporting the lead bar, and a lead bar and inner metal Assembling a mount portion with a ring, an outer metal ring, an electrode support rod, and a glass rod supporting the metal foil, and an internal glass tube supporting the electrode support rod; and inserting the mount portion into the inner sealing tube; A step of inserting the inner sealing tube in which the mount portion is inserted into the outer sealing tube, and an inner sealing tube in which the mount portion is inserted in the outer sealing tube in a state where the inner sealing tube is inserted in the outer sealing tube. Simultaneously shrinks the stop tube And the method comprising a step of welding the mounting portion by.

  Due to the above-described configuration, even when an internal glass tube having the same shape as that of the conventional glass tube is used in a double arc structure short arc type discharge lamp, the stress applied to the internal glass tube from the electrode support rod supporting the electrode Can be made as small as in the case of the single sealing structure. In addition, the welding end portion that causes the rupture becomes one, the reliability is improved, and the inspection time of the welded state can be shortened. Even if the outer diameter of the sealing portion that requires strength is increased, the outer diameter of the base does not increase, and overheating of the base can be prevented. Moreover, since a double sealing tube can be sealed at a time, even a double sealing structure is a sealing process equivalent to a single sealing, and the working time can be shortened.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to FIGS.

  Embodiment 1 of the present invention is a sealing of a short arc type discharge lamp in which an end portion on the discharge space side of an inner sealing tube is disposed in an intermediate portion of an inner glass tube, and the inner glass tube and the outer sealing tube are welded. It is a partial structure.

  FIG. 1 is an overall cross-sectional view showing a sealing part structure of a short arc type discharge lamp in Example 1 of the present invention. In FIG. 1, an arc tube 1 is a quartz glass tube filled with mercury. The anode 2 is a positive electrode. The cathode 3 is a negative electrode. A1 is the length from the discharge space side end surface of the internal glass tube to the anode front end surface.

  FIG. 2 is a partial cross-sectional view showing a sealing portion structure of a short arc type discharge lamp. In FIG. 2, the electrode support rod 4 is a metal member that supports the anode. The lead bar 5 is a conductive member for supplying electric power. The inner sealing tube 10 is a cylindrical glass member for hermetic sealing. The inner end portion 16 is an end portion of the inner sealing tube 10 on the discharge space side. The outer end portion 17 is an end portion of the inner sealing tube 10 on the fixing ring side. The outer sealing tube 11 is a cylindrical portion that is an extension of the arc tube. The glass rod 18 is a glass member that structurally connects the lead rod and the electrode support rod 4. The internal glass tube 6 is a glass member that holds the electrode support rod 4. The external glass tube 7 is a glass member that holds the lead rod 5. The metal foil 8 is a metal member that is interposed between the glass rod 18 and the inner glass tube 6 and electrically connects the inner metal ring and the outer metal ring. The fixing ring 9 is a metal member that suppresses the movement of the inner sealing tube in the axial direction. The internal metal ring 14 is a metal member that electrically connects the electrode support rod 4 and the metal foil 8. The outer metal ring 15 is a metal member that electrically connects the lead bar and the metal foil. The discharge space S is a space in which mercury and a rare gas are enclosed and discharge occurs.

  FIG. 3 is a partially enlarged cross-sectional view showing a sealing portion structure of a short arc type discharge lamp. In FIG. 3, the weld end 24 is the end of the welded portion between the inner glass tube and the outer sealing tube on the discharge space side. L1 is the axial length at which the inner glass tube and the inner sealing tube are welded. L2 is the axial length of the inner glass tube. FIG. 4 is a cross-sectional view showing a state in which the mounting component having the sealing portion structure of the short arc type discharge lamp is inserted into the inner sealing tube. In FIG. 4, the fixing ring 9 is a ring-shaped component for suppressing the movement of the inner sealing tube in the axial direction. The inner sealing tube 20 before welding is an inner sealing tube before being welded with a reduced diameter due to heat of a burner or the like. The inner end portion 26 is an end portion on the discharge space side of the inner sealing tube before welding. The outer end 27 is the end opposite to the discharge space of the inner sealing tube before welding.

  FIG. 5 is a cross-sectional view showing a state in which a mount component having a sealing portion structure of a short arc type discharge lamp is inserted into an outer sealing tube and disposed at a desired position. In FIG. 5, an outer sealing tube 21 before welding is an outer sealing tube before being welded with a reduced diameter by heat from a burner or the like. D3 is the outer diameter of the inner sealing tube 20 before welding. D4 is the inner diameter of the outer sealing tube 21 before welding.

  The sealing part structure and manufacturing method of the short arc type discharge lamp in Example 1 of the present invention configured as described above will be described. First, the overall structure of the short arc type discharge lamp will be described with reference to FIGS. The short arc type discharge lamp has an arc tube 1 having a swelled central portion, and a pair of an anode 2 and a cathode 3 which are opposed to each other in the arc tube 1. Furthermore, it has a mount part 19 composed of a series of metallic parts for supplying electric power from the outside to the internal electrodes of the discharge lamp and glass parts for holding them. Specifically, the mount component 19 includes an anode 2, an electrode support rod 4, a lead rod 5, a glass rod 18, an internal glass tube 6, an external glass tube 7, a metal foil 8, an internal metal ring 14, and an external metal ring 15. Is done.

As shown in FIG. 1, the internal glass tube 6 is disposed at a position of a length A1 from the anode front end surface. Since the inner sealing tube 10 is not exposed to the discharge space S, as shown in FIG. 3, the inner end 16 that is the end of the welded portion between the inner sealing tube 10 and the inner glass tube 6 is connected to the anode. 2 can be arranged close to. That is, A1 (FIG. 1) can be made smaller by A1 (FIGS. 14 and 16) than A2 (FIG. 14), and can be substantially equal to A3 (FIG. 13). That is,
A1 ≒ A3 ≒ A2-B1
It becomes. The electrode support rod is a cantilever beam supported by the internal glass tube, and a large force is applied to the internal glass tube due to the principle of leverage, but the electrode is closer to the anode than the conventional double sealing structure. By holding the support rod, the stress applied to the internal glass tube can be reduced to the same extent as in the case of the single sealing structure, and the internal glass tube can be prevented from being damaged.

  As shown in FIG. 3, the inner sealing tube 10 is welded between the outer sealing tube 11 and the inner glass tube 6 over a range of length L1. The outer sealing tube 11 and the inner glass tube 6 are welded on the discharge space side from the inner end portion 16. The inner end 16 of the inner sealing tube 10 is not exposed to the discharge space S. Since the inner sealing tube 10 is not exposed to the discharge space S, the welded end portion is only one place (one circumference) in the double sealing structure, which is the same as in the single sealing structure. . As a result, the number of crack generation factors is reduced, the reliability is improved, and the inspection time for the welded state can be shortened.

  In order to increase the strength (pressure resistance) with respect to the pressure when the discharge lamp is turned on, it is necessary to weld the mount component 19 and the both sealed tubes sufficiently. Therefore, it is preferable that the mount component 19 around the inner metal ring 14 and the inner sealing tube 10 be sufficiently familiar and welded. The axial length L1 (FIG. 3) where the inner sealing tube 10 and the inner glass tube 6 are welded is preferably sufficiently long.

  Further, the welded end portion 24 between the inner glass tube 6 and the outer sealing tube 11 serves as a starting point of a crack that causes a rupture when the discharge lamp is lit, so that the inner glass tube 6 and the outer sealing tube 11 are sufficiently connected. It is necessary to blend and weld. Moreover, in order to make electrode holding more stable, it is preferable that the axial length (L2-L1) (FIG. 3) where the outer sealing tube 11 and the inner glass tube 6 are welded is sufficiently long. The inner end 16 is preferably sufficiently separated from the weld end 24. That is, 0 <L1 <L2.

  When the thickness of the metal foil 8 is ignored, the outer diameter of the inner glass tube 6 is preferably equal to the outer diameter of both metal rings. The reason is as follows. When the outer diameters match, a series of parts have one cylindrical side surface, so that the electrode support bar 4 and glass parts arranged in the sealing part can be easily assembled before sealing. . Further, an airtight state between the inside and the outside of the arc tube 1 can be obtained more reliably, and oxidation of both metal rings can be prevented.

  Next, the mount component will be described with reference to FIG. A mount component 19 produced in the same manner as the conventional one is inserted into the inner sealing tube 20. When the maximum outer diameter of the mount component is D1 and the inner diameter of the inner sealing tube is D2, the mounting component 19 can be inserted into the inner sealing tube 20 by D1 <D2. When the mount component 19 is inserted into the inner sealing tube 20, it is obvious that all the outer diameters of the components constituting the mount component 19 are preferably equal.

  By providing the fixing ring 9, it is possible to suppress the inner sealing tube 20 before welding from moving in the axial direction to the side opposite to the electrode. The fixing ring 9 is fixed to the lead bar 5. When the fixing ring 9 is a metal, axial movement is suppressed by a method such as welding to the lead bar 5. When the fixing ring 9 is made of glass, axial movement is suppressed by a method such as fixing to the lead bar 5 with a stopper. The position of the fixing ring 9 is determined so that the inner end portion 26 of the inner sealing tube 20 can be disposed at a desired position in a state where the fixing ring 9 and the outer end portion 27 of the inner sealing tube 20 are in contact with each other. Therefore, when sealing is performed, the fixing ring 9 and the outer end portion 27 of the inner sealing tube 20 are in contact with each other.

  Next, a mounting component arranging method will be described with reference to FIG. The mount component 19 holding the inner sealing tube 20 is inserted into the outer sealing tube 21 before welding, and the anode 2 is disposed at a desired position in the discharge space S. When the outer diameter of the inner sealing tube 20 is D3 and the inner diameter of the outer sealing tube 21 is D4, the mounting part 19 holding the inner sealing tube 20 is attached to the outer side before welding by D3 <D4. It can be inserted into the sealing tube 21. The inside of the outer sealing tube (inside the discharge space) is brought into a negative pressure state and heated by a burner or the like to reduce the diameter of the outer sealing tube 21 and the inner sealing tube 20, and the outer sealing tube 21 and the inner sealing tube 20 and mount part 19 are welded. As described above, since the double sealing structure can be sealed at a time, the sealing process is the same as that in the case of the single sealing while the double sealing structure is achieved, and the sealing work time can be shortened.

  Sealing is similarly performed on the cathode 3 facing in the discharge space. The discharge space with both electrodes sealed is evacuated to enclose mercury and a rare gas. Thereafter, an unnecessary sealing tube around the fixing ring 9 is cut with a diamond cutter or the like, thereby completing a short arc type discharge lamp as shown in FIG. When the short arc type discharge lamp shown in FIG. 1 is cut at the portion of the external glass tube near the fixing ring, the entire length of the lamp can be shortened, and a compact short arc type discharge lamp (not shown) can be obtained. it can. In this case, when the mounting component is held in the inner sealing tube, the fixing ring can be easily separated from the inner sealing tube by simply bringing the metal fixing ring into contact with the inner sealing tube.

  As described above, in Example 1 of the present invention, the sealing portion structure of the short arc type discharge lamp is arranged such that the end portion on the discharge space side of the inner sealing tube is disposed in the middle portion of the inner glass tube, and the inner glass Since the tube and the outer sealing tube are welded, the end portion on the discharge space side of the inner sealing tube is not exposed to the discharge space, and the reliability of the double sealing structure is increased and the manufacturing efficiency is also improved.

  In the second embodiment of the present invention, a mount component is configured using a different-diameter inner glass tube having a small-diameter portion and a large-diameter portion, and an inner sealing tube is provided between the small-diameter portion and the large-diameter portion of the different-diameter inner glass tube. Sealing of the short arc type discharge lamp in which the inner glass tube and the outer sealing tube are welded so that the discharge space side end of the inner sealing tube is not exposed to the discharge space. It is a partial structure.

  FIG. 6 is a cross-sectional view of a short arc type discharge lamp in Example 2 of the present invention. In FIG. 6, the different diameter inner glass tube 36 is an inner glass tube having two different outer diameters. FIG. 7 is a partially enlarged view of a sealing portion of a short arc type discharge lamp. In FIG. 7, the inner sealing tube 10 is a cylindrical glass member for hermetic sealing. The outer sealing tube 11 is a cylindrical portion that is an extension of the arc tube. The small diameter portion 37 is a portion where the diameter of the different diameter internal glass tube is small. The large diameter portion 38 is a portion where the diameter of the different diameter internal glass tube is large. The inclined portion 39 is a portion between the large diameter portion and the small diameter portion of the different diameter inner glass tube. The outer diameter of the small-diameter portion 37 of the different-diameter inner glass tube is C1, and the outer diameter of the large-diameter portion 38 is C2. The length of the small diameter portion 37 in the axial direction is L4, and the length of the internal glass tube in the axial direction is L3. The inclined portion 39 has an inclined surface having an angle R with respect to the central axis of the different-diameter inner glass tube. The other parts are the same as the mounting parts shown in FIG. 1 and FIG.

  FIG. 8 is a view showing a state in which the different-diameter mount component 29 using the different-diameter inner glass tube is sealed in the inner sealing tube 20 before welding. The inner sealing tube 20 before welding is an inner sealing tube before being welded with a reduced diameter due to heat of a burner or the like. The inner end portion 26 is an end portion on the discharge space side of the inner sealing tube 20 before welding. The outer end portion 27 is an end portion on the fixing ring side of the inner sealing tube 20 before welding.

  The sealing part structure and manufacturing method of the short arc type discharge lamp in Example 2 of the present invention configured as described above will be described with reference to FIGS. As shown in FIGS. 7 and 8, the outer diameter of the small diameter portion 37 is C1, the inner diameter of the inner sealing tube 20 is C3, and the outer diameter of the large diameter portion 38 is C2. By setting C1 <C3 <C2, the portion outside the large diameter portion 38 of the different diameter mount component 29 can be inserted into the inner sealing tube 20 before welding. The inner end portion 26 of the inner sealing tube 20 before welding is brought into contact with the inclined portion 39 of the different diameter inner glass tube and stopped. The inclined portion 39 functions as a stopper for locking one end of the inner sealing tube 20. The outer end 27 of the inner sealing tube 20 before welding is in contact with the fixing ring 9. Therefore, the inclined portion 39 and the outer end portion 27 can suppress the movement of the inner sealing tube 20 in the axial direction before welding.

  Using the different-diameter inner glass tube 36, the different-diameter mount component 29 is produced in the same manner as in the first embodiment. The different-diameter mount component 29 is inserted into the inner sealing tube 20 before welding, and the axial movement is stopped by the fixing ring 9. The different diameter mount component 29 to which the inner sealing tube 20 before welding is fixed is inserted into the outer sealing tube and sealed in the same manner as in the first embodiment. The inner glass tube and fixing ring can stop the inner sealing tube from moving in the axial direction, so that the inner sealing tube wraps the mount part at the desired position, and the double sealed tube structure Can be sealed in one step. Further, since the inner sealing tube is fixed, the operation is easy.

  The different-diameter mount component 29, the inner sealing tube 10, and the outer sealing tube 11 are heated and welded by a burner or the like, and sealed so as to maintain an airtight state between the inside and the outside of the arc tube. By setting the angle R of the inclined portion 39 to 90 ° or less, the different-diameter inner glass tube 36, the inner sealing tube 10, and the outer sealing tube 11 can be well blended and welded. As a result, breakage starting from the vicinity of the inclined portion is less likely to occur.

  The mounting parts around the inner metal ring and the inner sealing tube are also well adapted and welded. In addition, the inner glass tube of different diameter and the outer sealing tube are also sufficiently familiar and welded. The length L1 of the small diameter portion where the inner sealing tube and the inner glass tube are welded is made sufficiently long. The axial length in which the outer sealing tube and the inner glass tube of different diameter are welded is also made sufficiently long. The inclined portion 39 is sufficiently separated from the welding end portion 24. That is, 0 <L4 <L3.

  Between the outer sealing tube 11 connected to the arc tube 1 and the different diameter mount component 29, the inner sealing tube 10 is interposed up to the vicinity of the inclined portion 39 of the inner glass tube 36 having a different diameter. The inner sealing tube 10 is not exposed to the discharge space S. Therefore, as compared with a conventional double sealing structure, the number of crack generation factors is reduced, the reliability is improved, and the inspection time for the welded state can be shortened. Moreover, since the stress concerning a different diameter internal glass tube becomes small like a single sealing structure similarly to Example 1, damage to a different diameter internal glass tube can be prevented.

  As described above, in the second embodiment of the present invention, the structure of the sealing portion of the short arc type discharge lamp is configured by using a different-diameter inner glass tube having a small-diameter portion and a large-diameter portion, By aligning the discharge space side end of the inner sealing tube between the small diameter portion and the large diameter portion of the glass tube, the inner glass so that the end of the inner sealing tube on the discharge space side is not exposed to the discharge space. Since the tube and the outer sealing tube are welded, the reliability and manufacturing efficiency of the double sealing structure can be improved.

  In Example 3 of the present invention, two inner sealing tubes having different outer diameters are arranged in series in the axial direction, and the end of the inner inner sealing tube on the discharge space side is larger than the smaller diameter portion of the different-diameter inner glass tube. A short arc type discharge lamp in which a different-diameter inner glass tube and an outer sealing tube are welded so that the end on the discharge space side of the inner inner sealing tube is not exposed to the discharge space in accordance with the inclined portion between the diameter portions. The sealing part structure.

  FIG. 9 is an overall cross-sectional view showing a sealing part structure of a short arc type discharge lamp in Example 3 of the present invention. In FIG. 9, the arc tube 1 is a quartz glass tube in which mercury is enclosed. The anode 2 is a positive electrode. The cathode 3 is a negative electrode. The inner inner sealing tube 12 is an inner sealing tube having a larger outer diameter than the outer inner sealing tube. The outer inner sealing tube 13 is an inner sealing tube having a smaller outer diameter than the inner inner sealing tube.

  FIG. 10 is a partially enlarged cross-sectional view showing a sealing part structure of a short arc type discharge lamp. In FIG. 10, the outer sealing tube 11 is a cylindrical portion that is an extension of the arc tube. The inner inner sealing tube 12 is an inner sealing tube having a larger outer diameter than the outer inner sealing tube. The outer inner sealing tube 13 is an inner sealing tube having a smaller outer diameter than the inner inner sealing tube. The inner metal ring 14 is a metal member that electrically connects the electrode support bar and the metal foil. The inner end portion 16 is an end portion on the discharge space side of the inner inner sealing tube. The welding end portion 24 is a terminal end on the discharge space side of the welding portion between the inner glass tube and the outer sealing tube. The joining side end portion 28 is an end portion that contacts the outer inner sealing tube of the inner inner sealing tube. The different diameter inner glass tube 36 is an inner glass tube having two different outer diameters. The inclined portion 39 is a portion between the large diameter portion and the small diameter portion of the different diameter inner glass tube. The discharge space S is a space in which mercury and a rare gas are enclosed and discharge occurs. L5 is the length at which the glass rod or metal foil is welded to the inner inner sealing tube.

  FIG. 11 is a cross-sectional view showing a state in which a different-diameter mount component using a different-diameter inner glass tube having a sealing portion structure of a short arc type discharge lamp is inserted into the inner sealing tube. In FIG. 11, the fixing ring 9 is a metal member that suppresses the movement of the inner sealing tube in the axial direction. The inner inner sealing tube 22 is an inner inner sealing tube before welding, and is an inner sealing tube having the same inner diameter and a larger outer diameter as compared with the outer inner sealing tube. The outer inner sealing tube 23 is an outer inner sealing tube before welding, and is an inner sealing tube having the same inner diameter and a smaller outer diameter as compared with the inner inner sealing tube. The inner end portion 26 is an end portion on the discharge space side of the inner inner sealing tube before welding. The outer end 27 is an end opposite to the discharge space of the outer inner sealing tube before welding. The different diameter mount component 29 is a mount component using a different diameter internal glass tube. The different diameter inner glass tube 36 is an inner glass tube having two different outer diameters. The inclined portion 39 is a portion between the large diameter portion and the small diameter portion of the different diameter inner glass tube.

  The structure of the sealed portion of the short arc type discharge lamp according to the third embodiment of the present invention configured as described above will be described in detail with reference to FIGS. As shown in FIG. 9, by using two inner sealing pipes arranged in series in the axial direction and having different outer diameters, the outer diameter of the sealing portion around the inner metal ring that requires high strength is increased. it can. Even if the outer diameter is increased, the outer diameter of the sealing portion around the outer metal ring does not increase, so there is no need to increase the size of the base. Since the base does not overheat, the lead bar will not oxidize and the lamp will not be damaged.

  As shown in FIG. 10, between the outer sealing tube 11 connected to the arc tube 1 and the different-diameter mounting component 29, the inner inner sealing tube 12 is provided up to the vicinity of the inclined portion 39 of the different-diameter inner glass tube 36. Intervene. The inner inner sealing tube 12 is not exposed to the discharge space S. Therefore, similarly to the first and second embodiments, the stress applied to the different-diameter inner glass tube 36 is reduced as in the single sealing structure, and the different-diameter inner glass tube 36 can be prevented from being damaged. Further, as compared with the conventional double sealing structure, since the portion that causes cracks is reduced, the reliability is improved and the inspection time for the welded state can be shortened.

  The length of welding of the inner inner sealing tube 12 and the different-diameter inner glass tube 36 shown in FIG. 10 is made sufficiently long. The inclined portion 39 is sufficiently separated from the welding end portion 24. In addition, the mounting parts around the inner metal ring 14 and the inner inner sealing tube 12 are sufficiently blended and welded. The length L5 at which the glass rod or metal foil and the inner inner sealing tube 22 are welded is made sufficiently long.

  With reference to FIG. 11, a method of manufacturing a double sealing structure using two types of inner sealing tubes will be described. Similar to Example 2, a different-diameter mount component 29 using a different-diameter inner glass tube 36 is produced. Two inner sealing tubes (inner inner sealing tube 22 and outer inner sealing tube 23) having different outer diameters are arranged in series in the axial direction. In the two types of inner sealing tubes, the outer diameter of the inner inner sealing tube 22 is large, and the outer diameter of the outer inner sealing tube 23 is small. The different-diameter mount component 29 is inserted into both inner sealing tubes, and the axial movement is stopped by the fixing ring 9. At this time, the inner end portion 26 of the inner inner sealing tube 22 is in contact with the inclined portion 39 of the different-diameter inner glass tube 36. The outer end 27 of the outer inner sealing tube 23 is in contact with the fixing ring 9. Therefore, the axial movement of both inner sealing tubes can be suppressed. In order to allow the different-diameter mount component 29 to be easily inserted into both inner sealing tubes, the inner diameters of both inner sealing tubes are made the same. The different-diameter mount component 29 to which both inner sealing tubes are fixed is inserted into the outer sealing tube and sealed in the same manner as in the second embodiment.

  As shown in FIG. 11, the inner glass tube 36 and the fixing ring 9 can stop the movement of both inner sealing tubes in the axial direction, so the two inner sealing tubes are not integrated. However, it is possible to easily perform the operation of sealing the double sealed tube structure in one step in a state where both inner sealed tubes wrap the different-diameter mount components 29 at desired positions. Although an example using two types of inner sealing pipes having different outer diameters has been described, two or more types of inner sealing pipes having different outer diameters depending on the required strength can be used. A heavy sealing structure can also be obtained easily.

  As described above, in the third embodiment of the present invention, the sealing portion structure of the short arc type discharge lamp has two inner sealing tubes having different outer diameters arranged in series in the axial direction, The end on the discharge space side is aligned with the inclined portion between the small diameter portion and the large diameter portion of the different diameter inner glass tube so that the end on the discharge space side of the inner inner sealing tube is not exposed to the discharge space. Since the inner glass tube and the outer sealing tube are welded, the reliability and manufacturing efficiency of the double sealing structure can be improved.

  Example 4 of the present invention is such that the end on the discharge space side of the inner diameter sealed tube having the two different outer diameters is not exposed to the discharge space. Is a sealed portion structure of a short arc type discharge lamp in which a different-diameter inner glass tube and an outer sealing tube are welded in accordance with an inclined portion between a small-diameter portion and a large-diameter portion of the different-diameter inner glass tube.

  FIG. 12 shows a state in which a different-diameter mounting component using a different-diameter inner glass tube is inserted into a different-diameter inner sealing tube in the manufacturing process of the sealing portion structure of the short arc type discharge lamp in Example 4 of the present invention. It is sectional drawing shown. In FIG. 12, the fixing ring 9 is a metal member that suppresses the axial movement of the different-diameter inner sealing tube. The inner end portion 26 is an end portion on the discharge space side of the different diameter inner sealed tube before welding. The outer end portion 27 is an end portion on the opposite side to the discharge space of the inner diameter sealed tube before welding. The different diameter mount component 29 is a mount component using a different diameter internal glass tube. The different diameter inner glass tube 36 is an inner glass tube having two different outer diameters. The inclined portion 39 is a portion between the large diameter portion and the small diameter portion of the different diameter inner glass tube. The different-diameter inner sealing tube 46 is an inner sealing tube having two types of outer diameters. The small-diameter portion 47 is a portion having an equal inner diameter and a smaller outer diameter than the large-diameter portion. The large-diameter portion 48 is a portion having an equal inner diameter and a larger outer diameter compared to the small-diameter portion.

  The structure of the sealing part of the short arc type discharge lamp in Example 4 of the present invention configured as described above will be described in detail. First, a method for producing a different diameter inner sealing tube will be described. A glass tube having a uniform inner diameter and outer diameter is heated by a burner or the like, and is shrunk in the axial direction while keeping the inner diameter constant, thereby producing a portion having a larger outer diameter. Alternatively, a glass tube having a uniform inner diameter and outer diameter is heated by a burner or the like, and is baked and stretched in the axial direction while keeping the inner diameter constant, thereby producing a portion having a smaller outer diameter. Alternatively, a plurality of glass tubes having the same inner diameter and different outer diameters are manufactured by heat welding with a burner or the like.

  Next, a manufacturing method of the sealing portion structure will be described with reference to FIG. In the same manner as in Example 2, a different-diameter mount component 29 using a different-diameter inner glass tube 36 is produced. The different-diameter mount component 29 is inserted into the different-diameter inner sealing tube 46, and the axial movement is stopped by the fixing ring 9. The different-diameter mount component 29 to which the different-diameter inner sealing tube 46 is fixed is inserted into the outer sealing tube and sealed in the same manner as in the second embodiment. Similar to the third embodiment, the inner-diameter glass tube 36 and the fixing ring 9 can stop the inner-diameter sealing tube 46 from moving in the axial direction. With the different-diameter inner sealing tube 46 enclosing the different-diameter mount component 29 at a desired position, the double-sealed tube structure can be sealed in one step. Further, since the different diameter inner sealing tube 46 is fixed, the operation becomes easy. The completed double sealed tube structure is substantially the same as the double sealed tube structure of Example 3.

  A different-diameter inner sealing tube 46 is interposed between the outer sealing tube connected to the arc tube and the different-diameter mount component 29 up to the vicinity of the inclined portion 39 of the different-diameter inner glass tube 36. The different diameter inner sealing tube 46 is not exposed to the discharge space. Therefore, compared with the conventional double sealing structure, since the part which becomes a crack generation factor decreases, reliability improves and the inspection time of a welding state can also be shortened. Further, the stress applied to the different diameter inner glass tube 36 is reduced to the same extent as in the case of the single sealed structure, and the damage to the different diameter inner glass tube 36 can be prevented.

  As described in the third embodiment, the length in which the different-diameter inner sealing tube 46 and the different-diameter inner glass tube 36 are welded is made sufficiently long. The inclined portion 39 is sufficiently separated from the welding end portion. By using the different-diameter inner sealing tube 46, the outer diameter of the sealing portion around the inner metal ring that requires high strength can be increased, as in the third embodiment. Even if the outer diameter is increased, the outer diameter of the sealing portion around the outer metal ring does not increase, so there is no need to increase the size of the base. The base is not overheated and the lamp is not damaged by oxidation of the lead rod.

  As described above, in Example 4 of the present invention, the end portion on the discharge space side of the inner diameter sealed tube having two different outer diameters is exposed to the discharge space in the short arc type discharge lamp sealing structure. So that the end on the discharge space side of the different-diameter inner sealing tube is aligned with the inclined portion between the small-diameter portion and the large-diameter portion of the different-diameter inner glass tube, Since the welded configuration is adopted, the reliability and manufacturing efficiency of the double sealing structure can be increased.

  The short arc discharge lamp sealing portion structure of the present invention is optimal as a short arc discharge lamp sealing portion structure used in the field of manufacturing semiconductors and liquid crystals.

It is a whole sectional view showing the sealing part structure of the short arc type discharge lamp in Example 1 of the present invention. It is a fragmentary sectional view which shows the sealing part structure of the short arc type discharge lamp in Example 1 of this invention. It is a partially expanded sectional view which shows the sealing part structure of the short arc type discharge lamp in Example 1 of this invention. It is sectional drawing which shows the state which inserted the mounting components of the sealing part structure of the short arc type discharge lamp in Example 1 of this invention in the inner side sealing tube. It is sectional drawing which shows the state which inserted the mounting components of the sealing part structure of the short arc type discharge lamp in Example 1 of this invention in the outer side sealing tube, and has arrange | positioned in the desired position. It is whole sectional drawing which shows the sealing part structure of the short arc type discharge lamp in Example 2 of this invention. It is a partially expanded sectional view which shows the sealing part structure of the short arc type discharge lamp in Example 2 of this invention. It is sectional drawing which shows the state which inserted the different diameter mount components using the different diameter internal glass tube of the sealing part structure of the short arc type discharge lamp in Example 2 of this invention in the inner side sealing tube. It is whole sectional drawing which shows the sealing part structure of the short arc type discharge lamp in Example 3 of this invention. It is a partially expanded sectional view which shows the sealing part structure of the short arc type discharge lamp in Example 3 of this invention. It is sectional drawing which shows the state which inserted the different diameter mounting components using the different diameter internal glass tube of the sealing part structure of the short arc type discharge lamp in Example 3 of this invention in the inner side sealing tube. It is sectional drawing which shows the state which inserted the different diameter mounting components using the different diameter internal glass tube of the sealing part structure of the short arc type discharge lamp in Example 4 of this invention in the inner side sealing tube. It is sectional drawing which shows the structure of the short arc type discharge lamp which has the conventional single sealing structure. It is sectional drawing which shows the structure of the short arc type discharge lamp which has the conventional double sealing structure. It is an expanded sectional view of the sealing part of the short arc type discharge lamp which has the conventional double sealing structure. It is the elements on larger scale of the sealing part of the short arc type discharge lamp which has the conventional double sealing structure. It is a figure explaining the manufacturing process of the sealing part of the short arc type discharge lamp which has the conventional double sealing structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting tube 2 Anode 3 Cathode 4 Electrode support rod 5 Lead rod 6 Internal glass tube 7 External glass tube 8 Metal foil 9 Fixing ring
10 Inner sealing tube
11 Outer sealing tube
12 Internal inner sealing tube
13 Outside inner sealing tube
14 Internal metal ring
15 External metal ring
16 Internal end
17 External end
18 Glass rod
19 Mounting parts
20 Inner sealed tube before welding
21 Outer sealing tube before welding
22 Inside inner sealed tube before welding
23 Outside inner sealing tube before welding
24 Weld end
26 Internal end
27 External end
28 Joint end
29 Different diameter mounting parts
36 Different diameter inner glass tube
37 Different diameter inner glass tube small diameter part
38 Large diameter part of different diameter inner glass tube
39 Different diameter inner glass tube inclined part
46 Different diameter inner sealing tube
47 Different diameter inner sealed tube small diameter part
48 Different diameter inner sealed tube large diameter part
49 Inclined part of inner diameter sealed pipe
50 Inner sealing tube
51 Sealed tube
54 Inner weld end
55 Outer weld end
56 Weld end
60 Inner sealing tube before welding

Claims (9)

A glass arc tube, a glass outer sealing tube connected to the arc tube, an inner sealing tube coaxially welded inside the outer sealing tube, and sealed in the arc tube A pair of electrodes, a metal electrode support rod for supporting the electrode, an internal metal ring electrically connected to the electrode, a lead rod for supplying power to the electrode, and an electric power to the lead rod Externally connected metal ring, a plurality of metal foils electrically connected to the internal metal ring and the external metal ring, an external glass tube for supporting the lead bar, the lead bar and the internal part A short-arc type discharge lamp having a double sealed structure comprising a metal ring, an outer metal ring, a glass rod for supporting the electrode support rod and the metal foil, and an inner glass tube for supporting the electrode support rod. In the sealing part structure, An end portion on the discharge space side of the inner sealing tube is disposed at an intermediate portion of the inner glass tube, and is wrapped and welded to the inner glass tube and the outer sealing tube. Sealing structure of arc type discharge lamp. The internal glass tube is a different-diameter internal glass tube having a large diameter portion and a small diameter portion, and the intermediate portion is an inclined portion between the small diameter portion and the large diameter portion. 2. The sealing part structure of the short arc type discharge lamp according to 1. 3. The short arc type discharge lamp sealing portion structure according to claim 2, wherein a taper angle R of the inclined portion is 0 ° <R ≦ 90 ° with respect to a central axis of the inner glass tube. . 4. The outer diameter of the outer glass tube, the outer metal ring, the glass rod, and the inner metal ring are all equal to the outer diameter of the small diameter portion of the different-diameter inner glass tube. Sealing structure of short arc type discharge lamp. The said inner sealing tube has multiple types of outer diameter, The sealing part structure of the short arc type discharge lamp in any one of Claims 1-4 characterized by the above-mentioned. 6. The short arc type discharge according to claim 5, wherein the inner sealing tube is an inner sealing tube in which a plurality of partial inner sealing tubes having different outer diameters are integrated in series in the axial direction. Lamp sealing part structure. The short arc type discharge lamp according to claim 5 or 6, wherein an outer diameter of a portion surrounding the outer metal ring in the inner sealing tube is smaller than an outer diameter of a portion surrounding the inner metal ring. Sealing part structure. The short arc type according to any one of claims 1 to 7, wherein a fixing ring is provided on an outer side in the axial direction of the outer glass tube, and an outer end portion of the inner sealing tube is in contact with the fixing ring. Sealing part structure of discharge lamp. An electrode, a metal electrode support rod that supports the electrode, an internal metal ring that is electrically connected to the electrode, a lead rod that supplies power to the electrode, and an electrical connection to the lead rod An outer metal ring, a plurality of metal foils electrically connected to the inner metal ring and the outer metal ring, an outer glass tube supporting the lead bar, the lead bar, the inner metal ring, and the Assembling the mount portion with an external metal ring, a glass rod for supporting the electrode support rod and the metal foil, and an internal glass tube for supporting the electrode support rod, and inserting the mount portion into the inner sealing tube A step of inserting the inner sealing tube in which the mount portion is inserted into the outer sealing tube, and a state in which the inner sealing tube in which the mount portion is inserted is inserted into the outer sealing tube. Said Manufacturing method of the short arc type discharge lamp, characterized in that the side sealing tube and said inner sealing tube by diameter simultaneously and a step of welding the mounting portion.

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