JP4986164B2 - Discharge lamp - Google Patents

Description

  The present invention relates to a discharge lamp used for a light source of an exposure apparatus such as a liquid crystal, a semiconductor, or a printed board. In particular, the present invention relates to a discharge lamp having a foil seal structure in which a sealing portion is sealed with a conductive foil made of molybdenum.

  As a discharge lamp used for a light source of an exposure apparatus, for example, there is one described in Patent Document 1. The structure of such a conventionally known discharge lamp will be described with reference to FIGS. 24 and 25. FIG.

  FIG. 24 is a cross-sectional view of the discharge lamp 1 along the longitudinal direction of the discharge vessel 2. FIG. 25 is an enlarged cross-sectional view of one discharge tube 1 in FIG. 24 on the side of one sealing tube 22 (the sealing tube 22 on the upper side in FIG. 24).

  A discharge lamp 1 shown in FIG. 24 includes a discharge vessel 2, a foil seal structure that seals the discharge vessel 2, a pair of electrodes 31 and 32 that are arranged to face each other inside the sealed discharge vessel 2, And a power supply structure for supplying power to the pair of electrodes 31 and 32.

The discharge vessel 2 of the discharge lamp 1 includes a substantially spherical arc tube 21 and a cylindrical sealing tube 22 connected to both ends thereof. Further, the discharge vessel 2 is made of, for example, quartz glass.
Inside the discharge vessel 2, an anode 31 and a cathode 32 made of, for example, tungsten are opposed to each other as a pair of electrodes 31 and 32, and mercury is enclosed as a luminescent material.

A power supply structure for supplying power to the pair of electrodes 31 and 32 when the lamp is lit is provided with the electrodes 31 and 32 at one end thereof, and a rod-shaped internal lead 33 extending along the central axis of the sealing tube 22 and the rod-shaped internal lead 33. A disk-shaped internal lead side conductor 34 provided on the outer periphery of the other end side of the internal lead 33 and a conductive foil that is joined to the outer surface of the internal lead side conductor 34 and extends along the longitudinal direction of the sealing tube 22 35, a disk-shaped external lead-side conductor 37 joined to the conductive foil 35, and a rod-shaped external lead 38 disposed on the central axis of the external lead-side conductor 37 and electrically connected thereto. Become.
In the power supply structure, the internal lead 33 and the external lead 38 are formed of tungsten, for example, and the internal lead side conductor 34, the external lead side conductor 37, and the conductive foil 35 are formed of molybdenum, for example. Thus, when power is supplied from a power source (not shown) connected to the external lead 38, the power supply structure is energized and power can be supplied to the electrodes 31 and 32.

  On the outer surface of the internal lead 33, a cylindrical internal lead holding cylinder 4 made of, for example, quartz glass is provided between the electrodes 31, 32 and the internal lead side conductor 34. In the internal lead holding cylinder 4, the outer peripheral surface of the internal lead 33 is brought into contact with the inner peripheral surface thereof, and the inner peripheral surface of the sealing tube 22 of the discharge vessel 2 is brought into contact with the outer surface thereof.

  A cylindrical external lead holding cylinder 6 made of, for example, quartz glass is provided on the outer surface of the external lead 38. The outer lead holding cylinder 6 is in contact with the outer surface of the external lead 38 on its inner surface, and the inner surface of the sealing tube 22 of the discharge vessel 2 is in contact with its outer surface.

  In the central axis direction of the sealing tube 22 of the discharge vessel 2, a cylindrical sealing insulator 5 made of, for example, quartz glass is disposed between the inner lead conductor 34 and the outer lead conductor 37. . The cylindrical sealing insulator 5 is provided with a lead recess 51 on each of a surface facing the internal lead conductor 34 and a surface facing the external lead conductor 37. In the lead recess 51, the other end of the internal lead 33 inserted through the central axis of the internal lead conductor 34 and one end of the external lead 38 inserted through the central axis of the external lead conductor 37 are arranged. . A conductive foil 35 is disposed on the outer peripheral surface of the sealing insulator 5.

The foil seal structure of the discharge lamp 1 is configured by partially heating and welding the sealing insulator 5 and the sealing tube 22 via the conductive foil 35.
The foil seal structure of the discharge lamp 1 formed in this way is the anode (reference numeral 31 in FIG. 24, not shown in FIG. 25) side (the lower side in FIG. 25) of the sealing insulator 5 shown in FIG. Thus, although the sealing tube 22 and the sealing insulator 5 are welded, a conductive foil side gap 92 is formed on the external lead 38 side (upper side of the drawing in FIG. 25) of the sealing insulator 5. The The conductive foil side gap 92 is formed at the time of cooling after forming the foil seal structure due to the difference in thermal expansion coefficient between the metal member constituting the conductive foil 35 and the glass member constituting the discharge tube 22. .

Japanese Utility Model Publication No. 06-060960

  The discharge lamp 1 having such a foil seal structure has a problem that the surface of the conductive foil 35 facing the external lead-side conductor 37 is oxidized and damaged when the lamp is continuously lit.

This is due to the internal configuration of the sealing tube 22 of the discharge lamp 1.
As shown in FIG. 25, the outer peripheral surface of the external lead 38 and the external lead holding cylinder are caused by the difference in thermal expansion coefficient between the metal member forming the external lead 38 and the glass member forming the external lead holding cylinder 6. An external lead-side gap 91 is formed between the inner peripheral surface 6 and the inner peripheral surface 6.
Further, as shown in FIG. 26, which is an enlarged view of a portion surrounded by a dotted circle in FIG. 25, the thermal expansion of each member is between the external lead holding cylinder 6 and the external lead side conductor 37. Due to the difference in the coefficient, a gap that communicates the outer lead side gap 91 and the conductive foil side gap 92 is formed.
As a result, the atmosphere A flows in from the end of the sealing tube 22 of the discharge vessel 2, and the conductive foil side gap 92 becomes the atmosphere A when the lamp is lit.

  In addition, when the lamp is turned on, power is supplied from the external lead 38, so that current concentration occurs around the joint 36 where the external lead-side conductor 37 and the conductive foil 35 are welded, and the conductive foil 35 is around the joint 36. The resistance heat at is increased. Further, the surface of the conductive foil 35 facing the external lead-side conductor 37 is heated by radiant heat from the external lead-side conductor 37 heated by the power supply.

  Thus, when the lamp is lit in the atmosphere A, the surface of the conductive foil 35 facing the external lead-side conductor 37 is heated, and the metal member constituting the conductive foil 35 is oxidized and damaged.

  Accordingly, an object of the present application is to provide a discharge lamp in which the surface of the conductive foil facing the external lead side conductor is prevented from being oxidized.

  A discharge lamp according to a first invention comprises a discharge vessel comprising an arc tube having a light emitting space therein and a sealing tube connected to both ends thereof, and a sealing insulator provided inside the sealing tube, An electrode disposed opposite to the arc tube inside the discharge vessel, and a conductive foil electrically connected to the electrode and provided between the sealing tube and the sealing insulator And a conductor that is electrically connected to the conductive foil via a joint and is provided outside the sealing insulator, and an external lead that is electrically connected to the conductor. The discharge lamp is characterized in that an oxidation protective film is provided on at least a surface of the conductive foil facing the conductor.

  A discharge lamp according to a second invention is characterized in that in the discharge lamp according to the first invention, the oxidation protective film is a rubidium-molybdenum double oxide.

  A discharge lamp according to a third aspect of the invention is the discharge lamp according to the first aspect of the invention, wherein the discharge lamp is outside the conductor, and is an external lead holding tube between the external lead and the sealing tube. A discharge lamp provided with a body, wherein an external lead side gap is provided between the external lead and the external lead holding cylinder along a longitudinal direction of the external lead, and the external lead side gap and the joint portion are provided. It is characterized in that a route that communicates with each other is provided.

  A discharge lamp according to a fourth invention is the discharge lamp according to the third invention, wherein a path forming member constituting a concave portion or / and a convex portion is provided between the conductor and the external lead holding cylinder. Thus, the route is configured.

  A discharge lamp according to a fifth invention is the discharge lamp according to the fourth invention, wherein the path forming member is provided with an opening continuous from the inner surface of the external lead holding cylinder to the outer surface of the conductor. Features.

  A discharge lamp according to a sixth invention is the discharge lamp according to the fourth invention, wherein the path forming member is provided with a striking portion that continues from the inner surface of the external lead holding cylinder to the outer surface of the conductor. It is characterized by.

  A discharge lamp according to a seventh aspect is characterized in that, in the discharge lamp according to the fourth aspect, the path forming member is constituted by a network structure composed of a plurality of linear members.

  A discharge lamp according to an eighth invention is characterized in that, in the discharge lamp according to the third invention, the path is formed by providing a concave portion or / and a convex portion in the conductor.

  A discharge lamp according to a ninth aspect of the invention is the discharge lamp according to the third aspect of the invention, wherein the outer surface of the conductor is held between the conductor and the outer lead holding cylinder. The conductive foil is provided in a continuous manner.

  A discharge lamp according to a tenth invention is the discharge lamp according to the third invention or the fourth invention, wherein a sealing insulator-side gap is provided between the conductor and the sealing insulator, and the external The conductor is provided with a through hole or / and a groove in the external lead so as to communicate the lead side gap and the sealing insulator side gap, and the sealing insulator side gap and the through hole or / and the The groove portion constitutes the path.

  A discharge lamp according to an eleventh invention is characterized in that, in the discharge lamp according to the third invention, a low melting point glass is provided between the external lead and the external lead holding cylinder.

  In the discharge lamp according to the first aspect of the present invention, the surface of the conductive foil facing the conductor is not exposed to oxygen in the atmosphere due to the above characteristics. Even if heated, the surface of the conductive foil facing the conductor can be prevented from being oxidized.

When the oxidation protective film and the sealing tube are in close contact with each other, when the member constituting the sealing tube is quartz glass, depending on the member constituting the oxidation protective film, for example, metal atoms or metal ions of the member are applied to the quartz glass. It may diffuse and inhibit the adhesion between the conductive foil provided with the oxidation protective film and the sealing tube.
The discharge lamp according to the second aspect of the present invention has a conductive foil provided with an oxidation protective film because of the above characteristics, since the atomic radius and ion radius of rubidium are large, and the diffusion of rubidium into quartz glass is small. It is possible to prevent the adhesion between the sealing tube and the sealing tube from being hindered.

As a means for providing the oxidation protection film, for example, a method of producing an oxidation protection film by applying an oxidation protection film forming solution made of, for example, an aqueous solution of rubidium nitrate to a conductive foil made of molybdenum and heating it. When this means is used, a step of applying the oxidation protective film forming solution to at least the surface of the conductive foil facing the conductor is necessary.
In the discharge lamp according to the first aspect of the present invention, when the external lead holding cylinder is provided outside the conductor, the oxidation protective film forming solution is between the inner surface of the external lead holding cylinder and the inner surface of the external lead. It is conceivable that it is applied to the surface of the conductive foil that faces the conductor through the gap between the conductor and the external lead holding cylinder.
However, in the discharge lamp in which the external lead holding cylinder is provided outside the conductor, the oxide protective film forming solution may not be applied to the surface of the conductive foil facing the conductor for the following reasons. .
When the discharge lamp forms a foil seal structure, the heated conductive foil is expanded toward the outside of the discharge lamp. Along with this, the conductor joined to the conductive foil is also moved toward the external lead holding cylinder, and the conductor and the external lead holding cylinder may be brought into close contact with each other. The foil seal structure is cooled after being formed, but the sealed portion of the conductive foil is fixed between the sealed sealing tube and the sealing insulator, so that the expanded conductive foil Most of them may hardly shrink, and the conductor and the external lead holding cylinder may remain in close contact with each other. While the conductor and the external lead holding cylinder are in close contact, the oxidation protective film forming solution may not flow. At this time, since the viscosity of the gas is lower than the viscosity of the liquid, the air flows between the closely attached conductor and the external lead holding cylinder, and the surface of the conductive foil facing the conductor is oxidized.・ The problem of damage could not be solved.
Therefore, in the discharge lamp according to the third invention, due to the above characteristics, the oxidation protection film forming solution is applied to at least the surface of the conductive foil facing the conductor via the path, and the surface of the conductive foil facing the conductor is formed. Oxidation can be prevented.

  In the discharge lamp according to the fourth aspect of the present invention, a path is formed along the concave part or / and the convex part due to the above characteristics, and the oxidation protective film forming solution is provided on at least the surface of the conductive foil facing the conductor through this path. The surface of the conductive foil facing the conductor can be prevented from being oxidized.

  In the discharge lamp according to the fifth aspect of the present invention, a path is formed along the opening of the path forming member due to the above characteristics, and an oxidation protective film forming solution is formed on at least the surface of the conductive foil facing the conductor through this path. The surface of the conductive foil facing the conductor can be prevented from being oxidized.

  According to the sixth aspect of the invention, the discharge lamp according to the sixth aspect has a path formed along the striking portion of the path forming member, and an oxidation protective film forming solution is formed on at least a surface of the conductive foil facing the conductor through the path. Can be applied to prevent the surface of the conductive foil facing the conductor from being oxidized.

According to the discharge lamp of the seventh invention, a path having a network structure is formed according to the above characteristics, and an oxidation protection film forming solution is applied to at least a surface of the conductive foil facing the conductor through the path, Oxidation of the surface facing the conductor can be prevented.
Furthermore, the discharge lamp according to the seventh invention can also solve the following problems.
When the lamp is turned on, the external lead-side conductor is expanded by heating, and may press the external lead holding cylinder. Since the external lead holding cylinder is fixed to the sealing tube, the pressure from the external lead-side conductor may become a stress on the external lead holding cylinder and may be damaged. Therefore, in the discharge lamp according to the fifth aspect of the present invention, a path forming member having a network structure is provided between the external lead side conductor and the external lead holding cylinder, so that the pressure from the external lead side conductor can be reduced. A path forming member having a network structure receives and expands when a stress is applied to a linear member constituting the network structure, and the amount of expansion is moved to a gap of the network structure.
In other words, the discharge lamp according to the fifth aspect of the present invention allows the external lead-side conductor to be pressed by the path forming member having a network structure while applying almost no stress to the external lead holding cylinder due to the above-described characteristics. By doing so, it is possible to prevent the external lead holding cylinder from being damaged.

  In the discharge lamp according to the eighth aspect of the present invention, a path is formed along the concave portion or / and the convex portion due to the above characteristics, and the oxidation protective film forming solution is provided on at least the surface of the conductive foil facing the conductor through the path. The surface of the conductive foil facing the conductor can be prevented from being oxidized.

  According to the discharge lamp of the ninth invention, a path is formed along the conductive foil positioned between the external lead-side conductor and the external lead holding cylinder, and at least the conductive foil passes through this path due to the above characteristics. The surface of the conductive foil that faces the conductor is coated with the oxidation protective film forming solution, so that the face of the conductive foil that faces the conductor can be prevented from being oxidized.

As described above, when the discharge lamp forms the foil seal structure, the heated conductive foil is expanded toward the outside of the discharge lamp, so that the external lead-side conductor and the external lead holding cylinder. Is closely attached. On the other hand, a sealing insulator-side gap is formed between the external lead-side conductor and the sealing insulator.
In view of the above, the discharge lamp according to the tenth invention has at least a conductor in the conductive foil through the through hole provided in the conductor and / or the groove provided in the external lead and the sealing insulator-side gap. The surface of the conductive foil is coated with the oxidation protective film forming solution, and the surface of the conductive foil facing the conductor can be prevented from being oxidized.

In the discharge lamps according to the first to ninth inventions, at least the surface of the conductive foil that faces the conductor is provided with an oxidation protective film due to the above-described characteristics, but this is opposed to the sealing tube in the conductive foil that is the back side thereof. In some cases, the surface side to be sealed is in close contact with the opposing sealing tube and the oxidation protection film is not provided. The conductive foil may be heated by the discharge heat from the arc tube being transferred to the conductive foil, in addition to the resistance heat by power feeding and the heating by the radiant heat from the external lead side conductor.
Therefore, the discharge lamp according to the eleventh aspect of the present invention suppresses the inflow of air into the gap outside the conductive foil and the oxidation of the portion of the conductive foil where the oxidation protection film is not generated, due to the above characteristics. Can do.

  A first embodiment of a discharge lamp 1 according to the present invention will be described with reference to FIGS.

FIG. 1 is a cross-sectional view along the longitudinal direction of the discharge lamp 1. FIG. 2 is an enlarged cross-sectional view of one discharge tube 1 in FIG. 1 on the side of one sealing tube 22 (the sealing tube 22 on the upper side in FIG. 1). FIG. 3 is an explanatory diagram of a surface 351 of the conductive foil 35 that faces the external lead-side conductor 37. FIG. 3A is an enlarged view of a portion surrounded by a dotted circle in the discharge lamp 1 of FIG. FIG. 3B is a perspective view of the discharge lamp 1 of FIG. 2, in which the sealing tube 22 and the external lead holding cylinder 6 are removed from the discharge lamp 1 of FIG.
1 to 3, the same components as those illustrated in FIGS. 24 to 26 are denoted by the same reference numerals.

  A discharge lamp 1 shown in FIG. 1 includes a discharge vessel 2, a foil seal structure that seals the discharge vessel 2, and a pair of electrodes 31 and 32 that are opposed to each other inside the sealed discharge vessel 2. A power supply structure for supplying power to the pair of electrodes 31 and 32, and a conductive foil 35 constituting the power supply structure is provided with an oxidation protective film (not shown in FIG. 1, reference numeral 71 in FIG. 3). And

The discharge vessel 2 of the discharge lamp 1 includes a substantially spherical arc tube 21 and a cylindrical sealing tube 22 connected to both ends thereof. As the member constituting the discharge vessel 2, a member having optical transparency is used, and in particular, when the discharge lamp 1 is used for an exposure apparatus, a member having ultraviolet transparency is used.
Further, as shown in the description of the foil seal structure described later, the sealing tube 22 constituting the discharge vessel 2 is preferably a glass member that can be heated and welded to the sealing insulator 5.
For these reasons, for example, quartz glass is used for the discharge vessel 2 as a glass member having ultraviolet transparency.

Inside the discharge vessel 2, a pair of electrodes 31, 32 are arranged opposite to each other on the arc tube 21 side, and a luminescent material is enclosed.
As a member constituting the pair of electrodes 31 and 32, since it is heated to a high temperature by discharge between the electrodes 31 and 32 when the lamp is turned on, a heat-resistant refractory metal or an alloy made of a refractory metal is used, An example of the refractory metal is tungsten.
As the light emitting material, the radiation is for example mercury is used with ultraviolet rays lamp turning, the added amount include range, for example 22 mg / cm ³ of 1~70mg / cm ^3. Further, for example, xenon gas is used as the start assisting gas for improving startability at the start of lamp lighting, and the amount of the sealed gas is within a range of 0.05 to 0.5 MPa, for example, 0.1 MPa.

  The power supply structure for supplying power to the pair of electrodes 31 and 32 when the lamp is lit is provided with the electrodes 31 and 32 at one end thereof and a rod-shaped internal lead 33 extending along the central axis of the sealing tube 22 and the rod-shaped internal lead 33. A disc-shaped inner lead side conductor 34 provided on the outer periphery of the other end side of the inner lead 33, and one end thereof is joined to the outer surface of the inner lead side conductor 34 and along the longitudinal direction of the sealing tube 22. A conductive foil 35 that extends, a disk-shaped external lead-side conductor 37 joined to the other end of the conductive foil 35, one end of the outer-lead-side conductor 37 is disposed on the central axis, and the other end is sealed. It consists of a rod-like external lead 38 protruding outward from the stop tube 22 (above the paper surface of the sealing tube 22 in FIG. 1).

  As a member of the power feeding structure (internal lead 33, internal lead side conductor 34, conductive foil 35, external lead side conductor 37 and external lead 38), it is natural that it has electrical conductivity, but when the lamp is lit. In consideration of the heat transfer of the discharge heat between the electrodes 31 and 32, it is necessary to have heat resistance. Therefore, a refractory metal or an alloy made of a refractory metal is used. Examples of the refractory metal include molybdenum, tungsten, tantalum, ruthenium and rhenium.

As the conductive foil 35 constituting the power feeding structure, a foil seal structure to be described later is formed via the conductive foil 35. Therefore, among the above-described high melting point metals, molybdenum that is particularly easy to process so as to reduce the thickness is suitable. Used for.
If the numerical example of this electrically conductive foil 35 is given, thickness will be 0.02-0.06 mm, for example, and width will be 6-15 mm, for example.

As shown in FIG. 3A, the joining of the external lead side conductor 37 and the conductive foil 35 is realized by providing a joint portion 36 by welding the outer peripheral surface of the external lead side conductor 37 and the conductive foil 35. it can. As a specific means of this welding, for example, fusion welding such as arc welding or pressure welding such as spot welding is used.
A plurality of (four in FIG. 3B) conductive foils 35 are provided on the outer peripheral surface of the external lead-side conductor 37 so as to correspond to the output of the discharge lamp 1. Each conductive foil 35 is provided with a joint portion 36 between the external lead-side conductor 37. The plurality of conductive foils 35 are arranged in parallel to each other along the longitudinal direction of the sealing tube 22 and are joined to the outer peripheral surface of the internal lead side conductor 34 by welding.

  In the direction of the central axis of the sealing tube 22 of the discharge vessel 2, a cylindrical sealing insulator 5 is disposed between the internal lead side conductor 34 and the external lead side conductor 37 (see FIG. 1). . On the outer peripheral surface of the sealing insulator 5, a plurality of conductive foils 35 that electrically connect the internal lead side conductor 34 and the external lead side conductor 37 are arranged apart from each other.

The foil seal structure of the discharge lamp 1 is configured by heating and welding a part of the sealing insulator 5 and the sealing tube 22 via the conductive foil 35 in order to hermetically seal the discharge vessel 2. The
As a member constituting the sealing insulator 5, a member that is easily welded to the sealing tube 22 is used, and in particular, the same member as the member of the sealing tube 22 is preferable. For example, when the sealing tube 22 is made of quartz glass, if the sealing insulator 5 is made of quartz glass, the sealing tube 22 and the sealing insulator 5 are heated by heating the sealing tube 22. It is suitably welded.

The sealing insulator 5 constituting the foil seal structure has a central axis of the sealing insulator 5 on each of a surface facing the internal lead side conductor 34 and a surface facing the external lead side conductor 37. A lead recess 51 is provided at the position.
In the sealing insulator 5, the other end of the internal lead 33 is inserted into the lead recess 51 provided on the surface facing the internal lead side conductor 34 and provided on the surface facing the external lead side conductor 37. One end of the external lead 38 is inserted into the lead recess 51 formed.

  The internal lead 33 having the other end inserted into the lead recess 51 of the sealing insulator 5 is provided with electrodes 31 and 32 at one end, and the electrodes 31 and 32 are internal in consideration of heat resistance during discharge. It becomes larger than the outer diameter of the lead 33. Therefore, the internal lead 33 provided with the electrodes 31 and 32 at one end is loaded with the weight of the electrodes 31 and 32, and the sealing insulator 5 inserted through the other end of the internal lead 33 is also connected to the electrodes 31 and 32. A weight of 32 is loaded. When the output of the discharge lamp 1 is, for example, 6.5 kW or more, the electrodes 31 and 32 are larger than the internal lead 33, so that the cylindrical internal lead holding cylinder 4 is disposed in the circumferential direction of the internal lead 33. It is preferable to provide support between the outer surface of the lead and the inner surface of the sealing tube 22 and assist the internal lead 33 provided with the electrodes 31 and 32 at one end. The internal lead holding cylinder 4 is provided between the electrodes 31 and 32 and the internal lead side conductor 34 in the longitudinal direction of the internal lead 33 so as to contact the internal lead side conductor 34.

  In addition, a conductive foil side gap (not shown in FIG. 1, reference numeral 91 in FIG. 3A), which will be described later, is formed in the outer peripheral direction of the external lead side conductor 37 electrically connected to the external lead 38. For this reason, the weight of the external lead 38 is mainly applied to the lead recess 51 provided in the sealing insulator 5. Since the sealing insulator 5 may be damaged by the load depending on the weight of the external lead 38, the cylindrical external lead holding cylinder 6 is sealed from the outer surface of the external lead 38 in the circumferential direction of the external lead 38. It is preferable to provide between the inner surface of the stop tube 22 and assist the support of the external lead 38. In addition, the external lead holding cylinder 6 is formed in the longitudinal direction of the external lead 38, outside the external lead side conductor 37 (the surface on the side facing the sealing insulator 5 with respect to the external lead side conductor 37). It is provided so that it may be located in the surface opposite side).

  As the members of the internal lead holding cylinder 4 and the external lead holding cylinder 6, a member that is easily welded to the sealing tube 22 is used, and the same member as the member of the sealing tube 22 is particularly preferable. For example, when the sealing tube 22 is made of quartz glass, if the internal lead holding cylinder 4 and the external lead holding cylinder 6 are made of quartz glass, the sealing tube 22 is heated, so that the sealing tube 22 is heated. The inner lead holding cylinder 4 and the sealing tube 22 and the outer lead holding cylinder 6 are welded together.

  The external lead holding cylinder 6 heated and welded to the sealing tube 22 is not welded to the external lead 38 having a different thermal expansion coefficient. For this reason, the space between the inner surface of the external lead holding cylinder 6 and the outer surface of the external lead 38 extends along the longitudinal direction of the external lead 38 (not shown in FIG. 1, notation in FIG. 2). 91).

  Further, between the outer surface of the other end of the conductive foil 35 on the side of the external lead 38 (the upper end of the conductive foil 35 in FIG. 2) and the sealing tube 22, the coefficient of thermal expansion of the members constituting them is provided. A conductive foil side gap 92 is formed due to the difference (see FIG. 2 and FIG. 3A for details).

  The other end of the conductive foil 35 surrounded by the conductive foil side gap 92 (the end on the upper side of the conductive foil 35 in FIG. 2) is joined to the external lead side conductor 37 (not shown in FIG. 2). As shown in FIG. 3A, the joint peripheral side gap 94 is interposed between the conductive foil 35 and the external lead-side conductor 37. Is formed. An oxidation protection film 71 is provided except for a portion of the surface 351 of the conductive foil facing the external lead-side conductor 37 through the bonding portion peripheral side gap 94 where the bonding portion 36 is bonded.

  The range of the surface of the conductive foil 35 facing the external lead-side conductor 37 (reference numeral 351 in FIG. 3A, not shown in FIG. 3B) is as shown in FIG. This is a range consisting of L1 facing in the central axis direction of the disk-shaped external lead-side conductor 37 and L2 facing in the circumferential direction of the disk-shaped external lead-side conductor 37 (front side of FIG. 3B). The two conductive foils 35 located on the side can be seen on the opposite side to the side facing the external lead side conductor 37).

  As shown in FIG. 3A, the oxidation protection film 71 is provided on at least a surface 351 of the conductive foil 35 facing the external lead-side conductor 6, but by a method for generating the oxidation protection film 71 described later, The conductive foil 35 is also provided at a portion surrounded by the conductive foil side gap 92. In particular, the portion of the conductive foil 35 surrounded by the conductive foil side gap 92, which is in close contact between the sealing tube 22 and the sealing insulator 5 (in the conductive foil 35 of FIG. 2). The lower side of the drawing is the heat transfer by the discharge heat between the electrodes 31 and 32 when the lamp is turned on (here, the heat transfer by the discharge heat is “electron current” and “discharge radiation” from the discharge between the electrodes 31 and 32). And heat transfer due to the heat transfer by the electrode and the electrodes 31 and 32 and the gas in the arc tube 21 due to the discharge, which are referred to as “contact heat transfer and gas convection heat transfer from the electrodes 31 and 32”. Therefore, it is preferable that an oxidation protective film 71 is provided also in this portion for the purpose of preventing oxidation due to heating.

The member of the oxidation protection film 71 is composed of a refractory metal constituting the conductive foil 35 or an alloy composed of a refractory metal and a double oxide composed of an alkali metal. For example, when the member constituting the conductive foil 35 is molybdenum and the alkali metal is, for example, cesium, a cesium-molybdenum double oxide is provided.
When the member constituting the conductive foil 35 is molybdenum, rubidium / molybdenum double oxide, which is a compound that is stable even at high temperatures, is preferable as the oxidation protective film 71.

A plurality of conductive foils 35 on which the oxidation protection film 71 is provided are provided on the outer surface of the external lead-side conductor 37. The surface of each conductive foil 35 facing the external lead-side conductor 37 (in FIG. 3A). Reference numerals 351 and (not shown in FIG. 3B) are provided with oxidation protective films 71, respectively.
As for the number of conductive foils 35, for example, in the case of a lamp having an output of 6.5 KW or more, four or more conductive foils 35 are necessary. The resistance heat of the member increases, and the radiant heat from the external lead-side conductor 37 also increases. Therefore, in the discharge lamp 1 including four or more conductive foils 35, at least the surface of the conductive foil 35 facing the external lead-side conductor 37 (reference numeral 351 in FIG. 3A, FIG. 3B). By providing the oxidation protection film 71 on the not shown), the oxidation preventing effect of the conductive foil 35 is remarkably obtained.

An example of the method for generating the oxidation protection film 71 is shown below.
Since the external lead holding cylinder 6 and the external lead side conductor 37 are not welded between the external lead holding cylinder 6 and the external lead side conductor 37 due to the difference in thermal expansion coefficient between the members, As shown in FIG. 3A, voids are formed. This gap communicates the external lead side gap 91 and the conductive foil side gap 92.
For this reason, for example, a rubidium nitrate solution is dropped from the outside of the external lead-side gap 91 located at the end of the discharge lamp 1 (the entrance of the external lead-side gap 91 above the paper surface of FIG. 2) as the oxidation protective film 71 formation solution. Then, the conductive foil side gap 92 is filled with the oxidation protective film 71 forming solution through the gap between the external lead holding cylinder 6 and the external lead side conductor 37. As a filling method, the conductive foil side gap 92 is reduced in pressure from the end of the sealing tube 22 of the discharge lamp 1 hermetically sealed, and the solution for forming the oxidation protective film 71 is pressed with an inert gas such as nitrogen. To fill. At this time, there is a joint peripheral side gap 94 between the conductive foil 35 and the external lead side conductor 37, and the joint peripheral side gap 94 and the conductive foil side gap 92 communicate with each other. The solution for forming the oxidation protection film 71 is also applied to the surface of the conductive foil 35 facing the external lead-side conductor 37 (not shown in FIG. 2, reference numeral 351 in FIG. 3A).
Next, the discharge lamp 1 is baked at, for example, 600 ° C. or higher while the conductive foil side gap 92 is filled with the oxidation protective film 71 forming solution.
Thereby, a high melting point metal such as molybdenum constituting the conductive foil 35 reacts with an alkali metal salt solution such as a rubidium nitric acid solution constituting the oxidation protective film 71 forming solution, and the conductive foil in the conductive foil 35 is reacted. A double oxide composed of a refractory metal such as a rubidium / molybdenum double oxide and an alkali metal is generated in a portion surrounded by the side gap 92. For example, a rubidium-molybdenum complex oxide is also generated on the surface of the conductive foil 35 coated with the oxidation protective film 71 forming solution, which faces the external lead-side conductor 37.

  3A shows a case where the conductive foil 35 is made of molybdenum and the external lead-side conductor 37 is made of tungsten other than molybdenum, for example, tungsten, so that only the outer surface of the conductive foil 35 is shown. An oxidation protection film 71 is formed. When the member of the external lead-side conductor 37 is the same molybdenum as the member of the conductive foil 35, the oxide protective film 71 formation solution in the external lead-side conductor 37 passes when filling the conductive foil-side gap 92. Since the oxidation protection film 71 formation solution is applied to the part that has been formed, the oxidation protection film 71 is generated.

In the discharge lamp 1 according to the first embodiment described above, a power source (not shown) is connected to the pair of external leads 38, and the lamp starts to be lit when power is supplied from the power source (not shown). When the lamp is lit, the joint peripheral side gap 94 communicates with the external lead side gap 91 and is therefore in the atmosphere. In this air atmosphere, the conductive foil 35 is heated by resistance heat around the joint portion 36 by power feeding and radiant heat from the external lead-side conductor 37.
The discharge lamp 1 according to the first embodiment is opposed to the external lead-side conductor 37 in the conductive foil 35 by providing an oxidation protection film 71 on the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37. The surface 351 to be exposed is not directly exposed to atmospheric oxygen. Thus, in the discharge lamp 1 according to the first embodiment, even if the surface 351 facing the external lead side conductor 37 in the conductive foil 35 is heated, the surface facing the external lead side conductor 37 in the conductive foil 35. Oxidation of 351 can be prevented.

  Further, when the lamp is lit, the conductive foil side gap 92 communicates with the external lead side gap 91 so that it is in the atmosphere. In this air atmosphere, the portion of the conductive foil 35 surrounded by the conductive foil side gap 92 is heated by the transfer of heat between the electrodes 31 and 32. In particular, since it is close to the electrodes 31 and 32, among the portions surrounded by the conductive foil side gap 92 in the conductive foil 35, the sealed portion side in close contact between the sealing tube 22 and the sealing insulator 5. (The lower side of the sheet of the conductive foil 35 in FIG. 2) is likely to receive heat transfer from the discharge heat. In the discharge lamp 1 according to the first embodiment, the oxidation protection film 71 is provided in a portion surrounded by the conductive foil side gap 92 in the conductive foil 35, so that the discharge lamp 1 is directly applied to oxygen in the atmosphere in the conductive foil side gap 92. Since it is not exposed, oxidation of the portion surrounded by the conductive foil side gap 92 in the conductive foil 35 can be prevented even if the heat transfer of the discharge heat is received.

  In addition, the discharge lamp 1 according to the first embodiment is provided with the oxidation protection film 71 in the portion surrounded by the conductive foil side gap 92 in the conductive foil 35, so that the conductive foil 35 can be used even in an environment heated to a high temperature. Therefore, the conductive foil joint 36 can be closer to the internal lead 38 side than the conventional discharge lamp 1. Thus, in the discharge lamp 1 according to the first embodiment, the external lead-side conductor 37 bonded to the conductive foil 35 can also move to the internal lead 33 side. Compared to the conventional discharge lamp 1, Since the length of the sealing tube 22 in the longitudinal direction (vertical direction shown in FIG. 1) can be shortened, the discharge lamp 1 can be downsized in the longitudinal direction.

When the oxidation protection film 71 and the sealing tube 22 are in close contact with each other, when the member constituting the sealing tube 22 is quartz glass, depending on the member constituting the oxidation protection film 71, for example, metal atoms or metal ions of the member May diffuse into the quartz glass and inhibit the adhesion between the conductive foil 35 provided with the oxidation protective film 71 and the sealing tube 22. This is because, when the lamp is turned on, when the metal atom or metal ion having kinetic energy due to the heat transfer of the discharge heats over the network structure made of silicon dioxide and diffuses, the radius of the metal atom radius or metal ion radius is increased. This is thought to be because the smaller one can easily get over the network structure.
Accordingly, the discharge lamp 1 according to the first embodiment is sealed with the conductive foil 35 provided with the oxidation protection film 71 for the following reason by forming the oxidation protection film 71 with a rubidium / molybdenum double oxide. It is possible to prevent the adhesion with the tube 22 from being inhibited.
The rubidium-molybdenum double oxide has a sufficiently large atomic radius and ionic radius of rubidium constituting it compared to other alkali metal atoms (for example, lithium and sodium) or metal ions (for example, lithium ion and sodium ion). Due to this, it is considered that there is little diffusion into quartz glass.

From the above, the configuration and effects of the discharge lamp 1 according to the first embodiment can be summarized as follows.
The discharge lamp 1 according to the first embodiment is provided with a discharge vessel 2 including a light emitting tube 21 having a light emitting space inside and a sealing tube 22 connected to both ends thereof, and the inside of the sealing tube 22. The sealing insulator 5, the electrodes 31, 32 arranged opposite to each other on the arc tube 21 side inside the discharge vessel 2, and the electrodes 31, 32 are electrically connected to the sealing tube 22. And a conductive foil 35 provided between the sealing insulator 5 and the conductive foil 35 via a joint 36 and provided outside the sealing insulator 5. In the discharge lamp 1 including the external lead-side conductor 37 and the external lead 38 electrically connected to the external lead-side conductor 37, at least the external lead-side conductor 37 in the conductive foil 35 is opposed to the discharge lamp 1. The surface 351 is provided with an oxidation protective film 71.

  In the discharge lamp 1 according to the first embodiment, the oxidation protection film 71 is provided on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, so that the external lead-side conductor 37 of the conductive foil 35 is provided. Since the opposing surface 351 is not exposed to oxygen in the atmosphere, even when the gap around the joint 94 is in the atmosphere and the conductive foil 35 is heated when the lamp is lit, the conductive foil 35 is opposed to the external lead-side conductor 37. The oxidation of the surface 351 to be performed can be prevented.

In addition to the above features, the discharge lamp 1 according to the first embodiment is characterized in that the oxidation protective film 71 is a rubidium-molybdenum double oxide.
Due to this feature, due to the large atomic radius and ion radius of rubidium, there is little diffusion of rubidium into the quartz glass, or the adhesion between the conductive foil 35 provided with the oxidation protective film 71 and the sealing tube 22. Inhibiting sex can be prevented.

  In the discharge lamp 1 according to the first embodiment described so far, as shown in FIG. 3B, the external lead-side conductor 37 has a disk shape. Next, the case where the external lead-side conductor 37 is not disk-shaped will be described with reference to FIGS. 4 and 5 as another example of the discharge lamp 1 according to the first embodiment. In another example of the first embodiment, the sectional view of the discharge lamp 1 is not substantially different from that in FIG. 1, and therefore FIG. 1 is used as a reference diagram.

FIG. 4 is an enlarged cross-sectional view of one discharge tube 1 in FIG. FIG. 5 is an explanatory diagram of a surface 351 of the conductive foil 35 that faces the external lead-side conductor 37, and is an enlarged view of a portion surrounded by a dotted circle in the discharge lamp 1 of FIG.
In FIGS. 4 and 5, the same components as those shown in FIGS.

The discharge lamp 1 shown in FIGS. 4 and 5 is different from the discharge lamp 1 shown in FIGS.
Differences from FIGS. 1 to 3 will be described as an explanation of the discharge lamp 1 of FIGS.

In order to provide the joint portion 22 for joining the external lead side conductor 37 and the conductive foil 35, as shown in FIG. 4, the external lead side conductor 37 is sealed from the outer peripheral surface of the disc-shaped member. A joining protrusion 371 that protrudes outward (upward on the paper surface in FIG. 4) 22 is provided. The number of the bonding protrusions 371 may be as many as the number of the conductive foils 35. When four conductive foils 35 are provided, for example, four bonding protrusions 371 are provided. As described above, the shape of the external lead-side conductor 37 includes a disk-shaped member and a plurality of joint protrusions 371 that protrude from the outer peripheral surface of the external lead-side conductor 37 toward the outside of the sealing tube 22 (upward in the drawing in FIG. 4). This is similar to the shape of a so-called external toothed washer.
By providing the joint protrusion 371, the facing area between the external lead-side conductor 37 and the conductive foil 35 increases, so that welding can be easily performed. Moreover, since the junction part 22 can enlarge the area joined to the external lead side conductor 371 and the area joined to the conductive foil 35, the amount of power supplied to the electrodes 31 and 32 can also be increased, and the large output. This can correspond to the discharge lamp 1 of FIG.

When the external lead-side conductor 37 has the joint protrusion 371, the surface 351 of the conductive foil 35 facing the external lead-side conductor 37 is in the longitudinal direction of the sealing tube 22 as shown in FIG. In the cross section, it refers to a region including the length L1 of the joint protrusion 371 of the external lead-side conductor 37.
Therefore, the oxidation protection film 71 provided on the conductive foil 35 may be provided on the surface 351 facing the external lead-side conductor 37 including at least the bonding protrusion 371 in the conductive foil 35.

  Further, a portion of the conductive foil 35 surrounded by the conductive foil side gap 92, which is in close contact between the sealing tube 22 and the sealing insulator 5 (in the conductive foil 35 of FIG. 4). On the lower side of the drawing, it is easy to receive heat transfer due to the discharge heat between the electrodes 31 and 32 when the lamp is lit.

Even when the external lead-side conductor 37 has the joint projection 371, the member of the oxidation protection film 71 includes a refractory metal constituting the conductive foil 35, an alloy made of a refractory metal, and an alkali metal. It is comprised with the double oxide which consists of. For example, when the member constituting the conductive foil 35 is molybdenum and the alkali metal is, for example, cesium, a cesium-molybdenum double oxide is provided.
When the member constituting the conductive foil 35 is molybdenum, rubidium / molybdenum double oxide, which is a compound that is stable even at high temperatures, is preferable as the oxidation protective film 71.

In the discharge lamp 1 according to another example of the first embodiment described above, a power source (not shown) is connected to the pair of external leads 38, and the lamp starts to be lit by being supplied with power from the power source (not shown). When the lamp is lit, the joint peripheral side gap 94 communicates with the external lead side gap 91 and is therefore in the atmosphere. In this air atmosphere, the conductive foil 35 is heated by resistance heat around the joint portion 36 by power feeding and radiant heat from the external lead-side conductor 37.
In the discharge lamp 1 according to another example of the first embodiment, the oxidation protection film 71 is provided on the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37 including the bonding protrusion 371. The surface 351 facing the external lead side conductor 37 including the bonding protrusion 371 in the conductive foil 35 is not directly exposed to oxygen in the atmosphere. Thereby, in the discharge lamp 1 according to another example of the first embodiment, even if the surface 351 facing the external lead-side conductor 37 including the bonding protrusion 371 in the conductive foil 35 is heated, the conductive foil It is possible to prevent oxidation of the surface 351 facing the external lead-side conductor 37 including the bonding protrusion 371 at 35.

  Further, when the lamp is lit, the conductive foil side gap 92 communicates with the external lead side gap 91 so that it is in the atmosphere. In this air atmosphere, the portion of the conductive foil 35 surrounded by the conductive foil side gap 92 is heated by the transfer of heat between the electrodes 31 and 32. In particular, since it is close to the electrodes 31 and 32, among the portions surrounded by the conductive foil side gap 92 in the conductive foil 35, the sealed portion side in close contact between the sealing tube 22 and the sealing insulator 5. (The lower side of the sheet of the conductive foil 35 in FIG. 4) is easily subjected to the heat transfer of the discharge heat. In the discharge lamp 1 according to another example of the first embodiment, the oxidation protection film 71 is provided in a portion surrounded by the conductive foil side gap 92 in the conductive foil 35, so that the atmosphere in the conductive foil side gap 92 is in the atmosphere. Therefore, even if the heat of the discharge heat is received, the portion of the conductive foil 35 surrounded by the conductive foil side gap 92 can be prevented from being oxidized.

  Further, the discharge lamp 1 according to another example of the first embodiment is provided in an environment heated to a high temperature by providing the oxidation protection film 71 in a portion surrounded by the conductive foil side gap 92 in the conductive foil 35. Further, since the oxidation of the conductive foil 35 is prevented, the joint portion 36 of the conductive foil can be brought closer to the internal lead 38 side than the conventional discharge lamp 1. Thus, in the discharge lamp 1 according to the first embodiment, the external lead-side conductor 37 bonded to the conductive foil 35 can also move to the internal lead 33 side. Compared to the conventional discharge lamp 1, Since the length of the sealing tube 22 in the longitudinal direction (vertical direction shown in FIG. 1) can be shortened, the discharge lamp 1 can be downsized in the longitudinal direction.

When the oxidation protection film 71 and the sealing tube 22 are in close contact with each other, when the member constituting the sealing tube 22 is quartz glass, depending on the member constituting the oxidation protection film 71, for example, metal atoms or metal ions of the member May diffuse into the quartz glass and inhibit the adhesion between the conductive foil 35 provided with the oxidation protective film 71 and the sealing tube 22. This is because, when the lamp is turned on, when the metal atom or metal ion having kinetic energy due to the heat transfer of the discharge heats over the network structure made of silicon dioxide and diffuses, the radius of the metal atom radius or metal ion radius is increased. This is thought to be because the smaller one can easily get over the network structure.
Accordingly, the discharge lamp 1 according to the first embodiment is sealed with the conductive foil 35 provided with the oxidation protection film 71 for the following reason by forming the oxidation protection film 71 with a rubidium / molybdenum double oxide. It is possible to prevent the adhesion with the tube 22 from being inhibited.
The rubidium-molybdenum double oxide has a sufficiently large atomic radius and ionic radius of rubidium constituting it compared to other alkali metal atoms (for example, lithium and sodium) or metal ions (for example, lithium ion and sodium ion). Due to this, it is considered that there is little diffusion into quartz glass.

From the above, the configuration and effects of the discharge lamp 1 according to another example of the first embodiment can be summarized as follows.
A discharge lamp 1 according to another example of the first embodiment includes a discharge vessel 2 including an arc tube 21 having a light emitting space therein and sealing tubes 22 connected to both ends thereof, The sealing insulator 5 provided inside, the electrodes 31 and 32 disposed facing each other on the arc tube 21 side inside the discharge vessel 2, and electrically connected to the electrodes 31 and 32 and A conductive foil 35 provided between the sealing tube 22 and the sealing insulator 5, and electrically connected to the conductive foil 35 via the joint 36 and the outside of the sealing insulator 5 In the discharge lamp 1, which includes an external lead-side conductor 37 having a joint protrusion 371 and an external lead 38 electrically connected to the external lead-side conductor 37, at least the conductive foil 35, the external lead side conductor 37 including the bonding projection 371 Characterized in that a protective oxide layer 71 on the surface 351 to be directed.

  In the discharge lamp 1 according to another example of the first embodiment, the oxidation protection film 71 is provided on the surface 351 facing the external lead-side conductor 37 including at least the bonding protrusion 371 in the conductive foil 35. Since the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37 including the bonding protrusion 371 is not exposed to oxygen in the atmosphere, the bonding-portion-side gap 94 becomes an atmospheric atmosphere when the lamp is turned on. Even if the foil 35 is heated, it is possible to prevent the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37 including the bonding protrusion 371 from being oxidized.

Further, in addition to the above characteristics, the discharge lamp 1 according to another example of the first embodiment is characterized in that the oxidation protective film 71 is a rubidium-molybdenum double oxide.
Due to this feature, since the atomic radius and ion radius of rubidium are large, the diffusion of rubidium into the quartz glass is small, so that the conductive foil 35 provided with the oxidation protection film 71 and the sealing tube 22 are in close contact with each other. Inhibiting sex can be prevented.

In the discharge lamp 1 according to the first embodiment described with reference to FIGS. 1 to 5, it is described that the oxidation protection film 71 is provided on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37.
However, in the discharge lamp 1 according to the first embodiment, when the external lead holding cylinder 6 is provided outside the external lead side conductor 37 (above the paper surface of the external lead conductor 37 in FIG. 2), In some cases, an oxidation protection film cannot be provided on the surface 351 of the conductive foil 35 facing the external lead-side conductor 37.
Therefore, as means for solving this problem, the discharge lamps 1 according to the second to ninth embodiments configured to be added to the discharge lamp 1 according to the first embodiment will be sequentially described below.

  A second embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIGS. Also in the second embodiment, the sectional view of the discharge lamp 1 is not substantially different from FIGS. 1, 2 and 3A, so that FIGS. 1, 2 and 3A are used as reference diagrams. .

6 is a perspective view of the discharge lamp 1 of FIG. 2, and is an exploded view in which the sealing tube 22 is removed from the discharge lamp 1 of FIG.
FIG. 7A is an enlarged view of only the path forming member 8 shown in FIG. FIG. 7B is a diagram in which the path forming member 8 of FIG. 7A is interposed between the external lead-side conductor 37 and the external lead holding cylinder 6, and X in FIG. It is sectional drawing when it sees from a direction.
In FIGS. 6 and 7, the same components as those shown in FIGS.

The discharge lamp 1 of FIGS. 6 and 7 is different from the discharge lamp 1 of FIGS. 1 to 3 in that a path forming member 8 is provided.
Differences from FIGS. 1 to 3 will be described as an explanation of the discharge lamp 1 of FIGS.

  As shown in FIG. 1, a discharge lamp 1 according to a second embodiment has a discharge vessel 2, a foil seal structure that seals the discharge vessel 2, and an opposed arrangement inside the sealed discharge vessel 2. A pair of electrodes 31 and 32 and a power feeding structure for feeding power to the pair of electrodes 31 and 32. The external lead holding cylinder 4 is provided on the outer periphery of the external lead 38 constituting the power feeding structure. Then, a path forming member 8 is provided between the external lead holding cylinder 6 and the external lead-side conductor 37 constituting the power feeding structure, and an oxidation protective film (see FIG. 1) is formed on the conductive foil 35 constituting the power feeding structure. Is provided with a notation (reference numeral 71) in FIG.

  6 shows a cylindrical sealing insulator 5 provided with a lead recess (not shown in FIG. 6, reference numeral 51 in FIG. 2) at the position of the central axis, and a rod-like shape in which one end is inserted into the lead recess. The external lead 38 and a disk-like shape that is inserted through the external lead joining hole at the center and outside the sealing insulator 5 (above the paper surface of the sealing insulator 5 in FIG. 6). The external lead-side conductor 37 and the external lead 38 are inserted through the central external lead insertion opening and provided outside the external lead-side conductor 37 (upper side of the paper surface of the external lead-side conductor 37 in FIG. 6). The circular foil-shaped path forming member 8 and the external lead 38 are inserted into the center external lead holding hole 62 and provided outside the external lead-side conductor 37 (above the paper surface of the path forming member 8 in FIG. 6). A cylindrical external lead holding cylinder 6 is shown. It is a diagram.

The magnitude relationship of each member is demonstrated using FIG.
The external lead holding cylinder 6 is provided so that its inner diameter L4 is larger than the outer diameter L3 of the outer lead 38 in order to insert the outer lead 38 into the outer lead holding hole 62 at its center. Further, the outer diameter L5 of the external lead holding cylinder 6 is provided to be smaller than the outer diameter L8 of the external lead side conductor 37.
The path forming member 8 has the same outer diameter L7 as the outer diameter L5 of the external lead holding cylinder 6. The inner diameter L6 of the path forming member 8 is the same as the outer diameter L3 of the external lead.

The path forming member 8 has an opening 811 extending from the inner periphery to the outer periphery. When the path forming member 8 is formed in a foil shape, it can be formed by cutting with a blade or the like.
The path forming member 8 needs to have heat resistance in consideration of resistance heat transfer by the external lead-side conductor 37 and discharge heat transfer when the lamp is lit. For this reason, as a member constituting the path forming member 8, a refractory metal or an alloy made of a refractory metal is used. Specific examples of the refractory metal include molybdenum, tungsten, tantalum, ruthenium and rhenium.

When the discharge lamp 1 is completed by interposing the path forming member 8 between the external lead-side conductor 37 and the external lead holding cylinder 6, heating by forming a foil seal structure or the external lead holding cylinder 6. By heating the sealing tube 22, the configuration shown in FIG.
FIG. 7B is a cross-sectional view of the path forming member 8 shown in FIG. Therefore, although not shown in FIG. 7B, the opening 811 continues in the depth direction of the drawing.
As shown in FIG. 7B, the opening 811 of the path forming member 8 is provided with a first taper 814 on the external lead holding cylinder 6 side in the cross section along the longitudinal direction of the sealing tube 22. It is done. The first taper 814 is provided from the flat surface contacting the external lead holding cylinder 6 in the path forming member 8 toward the external lead side conductor 37 so that the thickness of the path forming member 8 is reduced. It is done. A gap 61 is provided between the first taper 814 of the path forming member 8 and the external lead holding cylinder 6.
Since the first taper 814 of the path forming member 8 is provided so as to extend from the inner periphery to the outer periphery of the path forming member 8, the gap 61 also extends along the first taper 814 in the inner periphery of the path forming member. It is provided so that it may extend to the outer periphery.

Further, as shown in FIG. 7B, the opening 811 of the path forming member 8 has a second taper 815 on the external lead side conductor 37 side in the cross section along the longitudinal direction of the sealing tube 22. Provided. The second taper 815 is provided from the flat surface of the path forming member 8 that contacts the external lead-side conductor 37 toward the external lead holding cylinder 6 so that the thickness of the path forming member 8 is reduced. . A gap 375 is provided between the second taper of the path forming member 8 and the external lead-side conductor 37.
Since the second taper 815 of the path forming member 8 is provided so as to extend from the inner periphery to the outer periphery of the path forming member 8, the gap 375 also extends along the second taper 815 inside the path forming member 8. It is provided so as to extend from the circumference to the outer circumference.

  In the discharge lamp of the first embodiment in which the path forming member 8 is not provided, as a method of generating the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the above-described method is used. As described above, for example, a rubidium nitrate solution is dropped as an oxidation protective film 71 forming solution from the outside of the external lead side gap 91 (the entrance of the external lead side gap 91 above the plane of FIG. 2), and the external lead side conductivity in the conductive foil 35 is dropped. There is a method of applying the oxidation protective film 71 forming solution to the surface facing the body 37. At this time, the oxidation protection film 71 production solution passes between the external lead holding cylinder 6 and the external lead side conductor 37 (see FIG. 3A).

However, in the discharge lamp 1 according to the first embodiment, when the external lead holding cylinder 6 is provided outside the external lead side conductor 37 (above the paper surface of the external lead conductor 37 in FIG. 2), For the following reasons, the oxidation protection film 71 may not be provided on the surface 351 of the conductive foil 35 facing the external lead-side conductor 37.
In the discharge lamp 1 according to the first embodiment, when the foil seal structure is formed, the heated conductive foil 35 expands toward the outside of the discharge lamp 1 (the upper side of the sheet of the conductive foil 35 in FIG. 2). Is done. Along with this, the external lead side conductor 37 joined to the conductive foil 35 is also moved toward the external lead holding cylinder 6 so that the external lead side conductor 37 and the external lead holding cylinder 6 are brought into close contact with each other. It happened. Although the foil seal structure is cooled after being formed, the conductive foil 35 is fixed between the sealed sealing tube 22 and the sealing insulator 5, so that most of the expanded conductive foil 35 is In some cases, the external lead-side conductor 37 and the external lead holding cylinder 6 may remain in close contact with each other.
Thus, in the case of the discharge lamp 1 according to the first embodiment, when the external lead holding cylinder 6 is provided outside the external lead side conductor 37, the external lead side conductor 37 and the external lead holding are provided. In some cases, the oxidation protective film 71 generation solution could not flow in while in close contact with the cylinder 6 for use.
At this time, since the viscosity of the atmosphere is lower than the viscosity of the solution for forming the oxidation protective film 71, the atmosphere flows between the closely attached external lead-side conductor 37 and the external lead holding cylinder 6, and the conductive The problem that the surface 351 of the foil 35 that faces the external lead-side conductor 37 is exposed to oxygen in the atmosphere and is oxidized and damaged cannot be solved.

  For this reason, the discharge lamp 1 according to the second embodiment has a foil seal by interposing the path forming member 8 having the opening 811 between the external lead side conductor 37 and the external lead holding cylinder 6. When the structure is formed, the flat surface of the path forming member 8 and the external lead holding cylinder 6 are in close contact with each other, but a gap 61 is provided between the first taper 814 and the external lead holding cylinder 6. . Further, although the flat surface of the path forming member 8 and the external lead side conductive plate 37 are in close contact, a gap 375 is provided between the second taper 815 and the external lead holding cylinder 6.

When the external lead holding cylinder 6 is provided, the heated external lead holding cylinder 6 is only softened in the heating step of welding the external lead holding cylinder 6 and the sealing tube 22, and the path It only projects slightly towards the first taper of the forming member 8. For this reason, the external lead holding cylinder 6 hardly fills the first taper of the path forming member 8, and the gap 61 is held.
Even if the gap 61 between the first taper of the path forming member 8 and the external lead holding cylinder 6 is filled with the softened or melted external lead holding cylinder 6 in the heating process, the heating process is performed. Since the discharge lamp 1 is cooled to room temperature later, the gap 61 is formed in the discharge lamp 1 due to the difference between the thermal expansion coefficient of the member constituting the external lead holding cylinder 6 and the thermal expansion coefficient of the member constituting the path forming member 8. Provided.
For the above-described reason, a gap 61 is provided in the first tapered portion of the opening 811 of the path forming member 8. By providing the first taper of the route forming member from the outer periphery to the inner periphery of the route forming member, a gap 61 extending from the outer periphery of the external lead to the outer periphery of the route forming member 8 is provided.

Since the inner diameter L 6 of the path forming member 8 is the same as the outer diameter L 3 of the external lead 38, the gap 61 between the external lead holding cylinder 6 and the path forming member 8 is communicated with the external lead-side gap 91. The Further, since the outer diameter L7 of the path forming member 8 is the same as the outer diameter L5 of the external lead holding cylinder 6, the gap 61 between the external lead holding cylinder 6 and the path forming member 8 is It communicates with the joint peripheral side gap 94 via the conductive foil side gap 92 shown in FIG.
The gap 375 between the external lead side conductor 37 and the path forming member 8 is also communicated with the external lead side gap 91 and also with the conductive foil side gap 92.

  That is, the path forming member 8 is provided with an opening 811 extending from the external lead side gap 91 to the outer surface of the external lead side conductor 37, and this path is provided between the external lead side conductor 37 and the external lead holding cylinder 6. By interposing the forming member 8, the external lead side gap 91 and the conductive foil side gap 92 are communicated with each other. Through the connected path 9, the conductive foil side gap 92 is filled with the oxidation protective film 71 forming solution dropped from the external lead side gap 91. At this time, there is a joint peripheral side gap 94 between the conductive foil 35 and the external lead side conductor 37, and the joint peripheral side gap 94 and the conductive foil side gap 92 communicate with each other. Since the oxidation protection film 71 forming solution is applied to the surface of the conductive foil 35 facing the external lead-side conductor 37 (not shown in FIG. 2, reference numeral 351 in FIG. 3A), the second embodiment is applied. In the discharge lamp 1, an oxidation protection film 71 can be provided on at least a surface of the conductive foil 35 facing the external lead-side conductor 37 (not shown in FIG. 2, reference numeral 351 in FIG. 3A).

As described above, in the discharge lamp 1, in order to provide the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the external lead-side gap 91 and the conductive foil-side gap 92 are formed. A path 9 that communicates is provided in the path forming member 8, and as a result, the path 9 may communicate the external lead side gap 91 and the joint peripheral side gap 94.
For this reason, the path 9 provided in the circular foil-shaped path forming member 8 is not necessarily provided with both the first taper and the second taper, and the external lead side gap 91 and the conductive foil side gap 92 are communicated with each other. Either the first taper 814 or the second taper 815 may be used.
Further, the path 9 provided in the path forming member 8 does not necessarily need to be the opening 811 having the tapers 814 and 815, for example, the concave portion from the external lead holding cylinder 6 toward the external lead side conductor 37. If a recess is provided from the external lead side conductor 37 toward the external lead holding cylinder 6, a gap or a path forming member 8 is formed between the path forming member 8 and the external lead holding cylinder 6. A gap is provided between the external lead-side conductor 37 and this functions as the path 9.
Furthermore, since the path 9 of the path forming member 8 only needs to communicate the external lead side gap 91 and the conductive foil side gap 92, the size relationship of each member in the discharge lamp 1 is limited to that shown in FIG. It is not a thing. For example, when the outer diameter L5 of the external lead holding cylinder 6 is larger than the outer diameter L8 of the external lead-side conductor 37, the outer diameter L7 of the path forming member 8 is the outer diameter of the external lead-side conductor 37. If there is an opening 9 that is equal to or greater than L8 and communicates from the outer circumference to the inner circumference of the path forming member 8, the path 811 communicates the external lead side gap 91 and the conductive foil side gap 92. Function as.

  From the above, the configuration and effects of the discharge lamp 1 according to the second embodiment can be summarized as follows.

In the discharge lamp 1 according to the second embodiment, the discharge lamp 1 is outside the external lead-side conductor 37, and the external lead holding cylinder is provided between the external lead 38 and the sealing tube 22. 6, an external lead-side gap 91 is provided between the external lead 38 and the external lead holding cylinder 6 along the longitudinal direction of the external lead 38, and the external lead-side gap 91 is provided. And a path 9 in which the joint 36 communicates with each other.
With this feature, in the discharge lamp 1 according to the second embodiment, at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37 is applied to the conductive foil 35 through the path 9, and the oxidation protective film 71 formation solution is applied. It is possible to prevent oxidation of the surface 351 facing the external lead-side conductor 37 at 35.

Furthermore, in addition to the above features, the discharge lamp 1 according to the second embodiment has a path that forms a recess or / and a protrusion between the external lead-side conductor 37 and the external lead holding cylinder 6. By providing the forming member 8, the path 9 is configured.
Due to this feature, in the discharge lamp 1 according to the second embodiment, a path 9 is formed along the concave portion or / and the convex portion, and at least the external lead side conductor 37 in the conductive foil 35 is opposed to the path 9. The surface of the surface 351 is coated with the oxidation protective film 71 forming solution, so that the surface 351 of the conductive foil 35 facing the external lead-side conductor 37 can be prevented from being oxidized.

  In the discharge lamp 1 according to the second embodiment described so far, the external lead-side conductor 37 has a disk shape as shown in FIG. Next, a case where the external lead-side conductor 37 is not disk-shaped will be described with reference to FIGS. 8 and 9 as another example of the discharge lamp 1 according to the second embodiment. In another example of the second embodiment, the sectional view of the discharge lamp 1 is not substantially different from that of FIGS. 1, 4 and 5, and therefore FIGS. 1, 4 and 5 are used as reference diagrams. Moreover, since the path | route formation member 8 shown in FIG. 8 is the same as FIG. 7 (a), FIG. 7 (a) and FIG.7 (b) are also used as a reference figure.

FIG. 8 is a perspective view of the discharge lamp 1 of FIG. 2, and is an exploded view in which the sealing tube 22 is removed from the discharge lamp 1 of FIG.
FIG. 9 shows that the gap 61 functions as a path between the bonding protrusion 371 and the external lead holding cylinder 6 when the bonding protrusion 371 is provided in the disk-shaped portion of the external lead-side conductor 37. FIG. 5 is a cross-sectional view showing an enlarged portion of a disk-like member and a joining projection 371 in the external lead-side conductor 37.
In FIGS. 8 and 9, the same components as those shown in FIGS. 1, 4 and 5 are denoted by the same reference numerals.

The discharge lamp 1 of FIGS. 8 and 9 is provided with a bonding projection 371 on the external lead-side conductor 37, and a gap 61 is provided between the bonding projection 371 and the external lead holding cylinder 6. Thus, it is different from the discharge lamp 1 of FIGS.
As an explanation of the discharge lamp 1 of FIGS. 8 and 9, differences from FIGS. 6 and 7 will be described.

  FIG. 8 shows a cylindrical sealing insulator 5 provided with a lead recess (not shown in FIG. 8, reference numeral 51 in FIG. 2) at the position of the central axis, and a rod-like shape in which one end is inserted into the lead recess. The external lead 38 and a disk-like shape that is inserted through the external lead joining hole at the center and provided outside the sealing insulator 5 (above the paper surface of the sealing insulator 5 in FIG. 8). External lead-side conductor 37, a joint projection 371 projecting toward the external lead holding cylinder 6 on the outer periphery of the external lead-side conductor 37, and the external lead 38 through the external lead insertion port. In addition, a circular foil-shaped path forming member 8 provided outside the external lead-side conductor 37 (above the paper surface of the external lead-side conductor 37 in FIG. 8), and an external lead holding hole centered on the external lead 38 62 and external lead side conductor 7 of the outer and a cylindrical external lead the cylindrical retaining member 6 provided on the (paper above the path forming member 8 of FIG. 8) is a diagram showing.

The magnitude relationship of each member is demonstrated using FIG.
The external lead holding cylinder 6 is provided so that its inner diameter L4 is larger than the outer diameter L3 of the outer lead 38 in order to insert the outer lead 38 into the outer lead holding hole 62 at its center. Further, the outer diameter L5 of the external lead holding cylinder 6 is smaller than the outer diameter L8 of the external lead-side conductor 37 and is the same as the inner diameter L9 of the joint protrusion 371 of the external lead-side conductor 37. It is provided as follows.
The path forming member 8 has the same inner diameter L6 as the outer diameter L3 of the external lead. Further, since the outer diameter L7 of the path forming member 8 is the same as the outer diameter L5 of the external lead holding cylinder 6, it is the same as the inner diameter L9 of the bonding protrusion 371 of the external lead side conductor 37.

  The configuration of the path forming member 8 shown in FIGS. 8 and 9 is the same as the configuration of the path forming member 8 shown in FIG.

  As shown in FIG. 8, when the opening 811 of the path forming member 8 is provided toward the bonding protrusion 371 of the external lead-side conductor 37, the bonding protrusion 371 is inserted from the external lead-side gap 91. A communicating gap (not shown in FIG. 8, reference numerals 61 and 815 in FIG. 7B) is provided.

The configuration on the inner surface of the bonding projection 371 will be described with reference to FIG.
As shown in FIG. 9, the end surface of the external lead holding cylinder 6 is bent between the outer surface of the path forming member 8 and the inner surface of the bonding projection 371 extending in the vertical direction from the outer surface of the path forming member 8. The By this bending, a gap 63 surrounded by the external lead holding cylinder 6, the bonding projection 371, and the path forming member 8 is provided. This gap 63 is provided along the inner surface of the bonding projection 371 (so as to extend from the back to the front of FIG. 9).
That is, a gap (reference numerals 61 and 375 in FIG. 9) extending along the opening (reference numeral 811 in FIG. 8) of the path forming member 8 and a gap 63 extending along the inner surface of the bonding projection 371 are communicated. .

  As described above, the external lead-side gap 91 and the conductive foil-side gap 92 are communicated with each other through the opening 811 of the path forming member 8 and the gap between the inner surface 63 of the bonding protrusion 371. Through the connected path 9, the conductive foil side gap 92 is filled with the oxidation protective film 71 forming solution dropped from the external lead side gap 91. At this time, a joint peripheral side gap 94 exists also between the conductive foil 35 and the external lead side conductor 37 including the joint protrusion 371, and the joint peripheral side gap 94 and the conductive foil side gap 92 are Therefore, the oxidation protection film 71 is formed on the surface (not shown in FIG. 4, reference numeral 351 in FIG. 5) facing the external lead-side conductor 37 including the bonding protrusion 371 in the conductive foil 35. Since the solution is applied, in the discharge lamp 1 according to another example of the second embodiment, at least the surface 351 facing the external lead-side conductor 37 including the bonding protrusion 371 in the conductive foil 35 is protected against oxidation. A film 71 can be provided.

  As described above, the discharge lamp 1 shown in FIGS. 8 and 9 has the same functions and effects as those of the discharge lamp 1 of FIGS. 6 and 7 even when the external lead-side conductor 37 has the bonding protrusion 371. Can be obtained.

In the discharge lamp 1 according to the second embodiment shown in FIGS. 6 to 9, the opening 811 provided in the path forming member 8 has tapers 814 and 815, so that the external lead-side conductor 37 and the external lead are held. A concave portion or / and a convex portion due to the path forming member 8 are interposed between the cylindrical body 6 and gaps 61 and 375 along the concave portion or the convex portion are provided.
Next, as a discharge lamp 1 according to a third embodiment, a case where the openings 811 are not provided with the tapers 814 and 815 will be described with reference to FIGS. Also in the third embodiment, the sectional view of the discharge lamp 1 is not substantially different from that of FIGS. 1, 2, and 3A, so that FIGS. 1, 2, and 3A are used as reference diagrams. .

First, a first example of the path forming member 8 according to the third embodiment will be described with reference to FIG.
FIG. 10A is an enlarged view of only the path forming member 8. FIG. 10B is a diagram in which the path forming member 8 of FIG. 10A is interposed between the external lead-side conductor 37 and the external lead holding cylinder 6, and X in FIG. It is sectional drawing when it sees from a direction.
In FIG. 10, the same components as those shown in FIGS.

The path forming member 8 in FIG. 10 is different from the path forming member 8 in FIG. 7 in that an opening 811 having a large opening in the circumferential direction is provided, and the opening 811 is not tapered.
As a description of the path forming member 8 in FIG. 10, differences from the path forming member 8 in FIG. 7 will be described.

As shown in FIG. 10A, the substantially circular foil-shaped path forming member 8 is provided with an opening 811 that opens from the inner periphery to the outer periphery and opens in the circumferential direction.
When the discharge lamp 1 is completed by interposing the path forming member 8 between the external lead-side conductor 37 and the external lead holding cylinder 6, heating by forming a foil seal structure and the external lead holding cylinder 6 are performed. By the heating of the sealing tube 22, the configuration shown in FIG.
FIG. 10B is a cross-sectional view of the path forming member 8 shown in FIG. For this reason, although not shown in FIG. 10B, the opening 811 continues in the depth direction of the drawing.

As shown in FIG. 10B, in the case of the path forming member 8 having the opening 811 that opens in the circumferential direction, the path forming member 8 is interposed between the external lead holding cylinder 6 and the external lead side conductor 37. In this portion, the external lead holding cylinder 6 and the external lead-side conductor 37 are in contact with each other.
A gap 61 surrounded by the bent external lead holding cylinder 6 and the external lead-side conductor 37 is provided on the end surface of the opening 811 of the path forming member 8.
Since the opening 811 opened in the circumferential direction in the path forming member 8 is provided so as to extend from the inner periphery to the outer periphery of the path forming member 8, the gap 61 also extends along the opening 811 opened. It is provided so as to extend from the inner periphery to the outer periphery.
The gap 61 functions as a path 9 that communicates the external lead side gap 91 and the conductive foil side gap 92, and at least the surface of the conductive foil 35 that faces the external lead side conductor 37 (not shown in FIG. 2, FIG. 3). An oxidation protective film 71 can be provided on the reference numeral 351 in FIG.

  As shown in FIG. 10 (b), an opening 811 that opens in the circumferential direction provided in the path forming member 8 is configured as a recess between the external lead-side conductor 37 and the external lead holding cylinder 6. . A gap 61 is formed by the recess formed by the path forming member 8, and the gap 61 functions as a path 9 that connects the external lead side gap 91 and the joint peripheral side gap 94.

  From the above, the discharge lamp 1 according to the first example of the third embodiment is provided with the path forming member 8 having the opening 811 opened in the circumferential direction, whereby the discharge lamp according to the second embodiment. The same action and effect as 1 can be obtained.

  Further, the path forming member 8 shown in FIG. 10A can also be provided on the external lead-side conductor 37 having the bonding protrusion 371 as shown in FIG. In this case, the gap 61 provided along the opening 811 opened in the circumferential direction of the path forming member 8 is arranged so that the external lead-side gap 91 and the gap 63 provided on the inner surface of the bonding projection 371 communicate with each other. As a result, the external lead side gap 91 and the joint peripheral side gap 94 can be communicated with each other.

Next, a second example of the path forming member 8 according to the third embodiment will be described with reference to FIG.
FIG. 11A is an enlarged view of only the path forming member 8. FIG. 11B is a diagram in which the path forming member 8 of FIG. 11A is interposed between the external lead-side conductor 37 and the external lead holding cylinder 6, and X in FIG. It is sectional drawing when it sees from a direction.
In FIG. 11, the same components as those shown in FIGS.

The path forming member 8 in FIG. 11 is different from the path forming member 8 in FIG. 7 in that the opening 811 is partially spiraled and the opening 811 is not tapered.
As a description of the path forming member 8 in FIG. 11, differences from the path forming member 8 in FIG. 7 will be described.

As shown in FIG. 11A, the substantially circular foil-shaped path forming member 8 opens from the inner periphery to the outer periphery, and the opening 811 overlaps.
When the discharge lamp 1 is completed by interposing the path forming member 8 between the external lead-side conductor 37 and the external lead holding cylinder 6, heating by forming a foil seal structure or the external lead holding cylinder 6. By the heating of the sealing tube 22, the configuration shown in FIG.
FIG.11 (b) is sectional drawing when it sees from the X direction of the path | route formation member 8 shown to Fig.11 (a). For this reason, although not shown in FIG. 11B, an opening 811 overlapping in the depth direction of the paper surface continues.

As shown in FIG. 11B, in the case of the spiral path forming member 8 that partially overlaps with the opening 811, the external lead side conductor 37 and the external lead side conductor 37 abut on the external lead side conductor 37 side. A gap 375 is provided that includes an opening 811 of the path forming member 8 and a portion of the path forming member 8 that overlaps the opening 811.
Since the overlapping portion in the path forming member 8 is provided so as to extend from the inner periphery to the outer periphery, the gap 375 is also provided so as to extend from the inner periphery to the outer periphery of the path forming member 8 along the overlapping portion. .

Further, on the side of the external lead holding cylinder 6, a gap 61 is provided that is surrounded by the bent external lead holding cylinder 6 and the opening 811 of the path forming member 8 facing this.
Since the opening 811 of the path forming member 8 is provided so as to extend from the inner periphery to the outer periphery, the gap 61 is also formed along the opening 811 from the inner periphery to the outer periphery of the path forming member 8.

  These gaps 61 and 375 function as a path 9 that connects the external lead side gap 91 and the conductive foil side gap 92, and at least a surface of the conductive foil 35 that faces the external lead side conductor 37 (not shown in FIG. An oxidation protective film 71 can be provided on the reference numeral 351 in FIG.

  As shown in FIG. 11B, the overlapping portion of the opening 811 provided in the path forming member 8 is configured as a convex portion and a concave portion between the external lead side conductor 37 and the external lead holding cylinder 6. Is done. A gap 61 is formed by the convex portion by the path forming member 8, and a gap 375 is formed by the concave portion. These gaps 61 and 375 are external lead side gaps (not shown in FIG. 11B, reference numeral 91 in FIG. 2). And a space 9 on the periphery of the joint (not shown in FIG. 11B, reference numeral 94 in FIG. 3A).

  From the above, the discharge lamp 1 according to the second example of the third embodiment is related to the second embodiment by including the path forming member 8 having the opening 811 opened in the circumferential direction. The same operation and effect as the discharge lamp 1 can be obtained.

  Moreover, the path | route formation member 8 shown to Fig.11 (a) can also be provided in the external lead side conductor 37 which has the protrusion 371 for a joining as shown in FIG. In this case, the gap 61 provided along the opening 811 opened in the circumferential direction of the path forming member 8 is arranged so that the external lead-side gap 91 and the gap 63 provided on the inner surface of the bonding projection 371 communicate with each other. As a result, the external lead side gap 91 and the joint peripheral side gap 94 can be communicated with each other.

  Thus, as described in the discharge lamp 1 according to the third embodiment with reference to FIGS. 10 and 11, the inner circumference between the external lead-side conductor 37 and the external lead holding cylinder 6 is the same. If the path forming member 8 having a concave portion or / a convex portion extending from the outer periphery to the outer periphery is interposed, a path 9 that connects the external lead side gap 91 and the joint peripheral side gap 94 can be provided.

Therefore, the path forming member 8 shown in the discharge lamp 1 in the second embodiment and the third embodiment is provided with the opening 811 extending from the inner periphery to the outer periphery of the path forming member. However, a fourth embodiment will be described as an example different from such an opening 811.
A fourth embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIGS. Also in the fourth embodiment, since the sectional view of the discharge lamp 1 is not substantially different from that in FIG. 1, FIG.

FIG. 12A is a perspective view of the discharge lamp 1 of FIG. 2, and is an exploded view in which the sealing tube 22 and the external lead holding cylinder 6 are removed from the discharge lamp 1 of FIG.
FIG. 12B is a view as seen from the outside of FIG. 12A (above the paper surface of the path forming member 8 of FIG. 12A). The outer diameter of the path forming member 8 and the external lead side conductor 37 It is the figure which looked at the magnitude relationship with the outer diameter of.
FIG. 13A is a cross-sectional view taken along the central axis of the sealing insulator 5 of the discharge lamp 1 in FIG. FIG. 13B is a view when the external lead holding cylinder 6 is inserted into the external lead from the outside of the path forming member 8 (upper side in the drawing) in FIG. 13A.
FIG. 14 is a view when the discharge lamp 1 is completed in FIG. 13B, and in the discharge lamp 1 of FIG. 1, one sealing tube 22 (the sealing tube 22 on the upper side in FIG. 1) side. FIG.
FIG. 15 is an enlarged view of a portion surrounded by a dotted circle of the discharge lamp 1 in FIG.
12 to 15, the same components as those illustrated in FIGS. 1 to 3 are denoted by the same reference numerals.

In the discharge lamp 1 of FIGS. 12 to 15, the path forming member 8 is larger in diameter than the outer diameter of the external lead-side conductor 37 and the opening 811 is not provided from the inner periphery to the outer periphery of the path forming member 8. This is different from the discharge lamp 1 of FIGS. 6 and 7.
As a description of the discharge lamp 1 of FIGS. 12 to 15, differences from FIGS. 6 and 7 will be described.

  FIG. 12 shows a cylindrical sealing insulator 5 provided with a lead recess (not shown in FIG. 12, reference numeral 51 in FIG. 13) at the position of the central axis, and a rod-like shape with one end inserted into the lead recess. The external lead 38 and a disk-like shape provided through the external lead 38 in the center external lead joint hole and provided outside the sealing insulator 5 (above the paper surface of the sealing insulator 5 in FIG. 12). The external lead-side conductor 37 and the external lead 38 are inserted through the center external lead insertion opening and provided outside the external lead-side conductor 37 (upper side of the paper surface of the external lead-side conductor 37 in FIG. 12). It is the figure which showed the circular foil-shaped path | route formation member 8. FIG.

As shown in FIGS. 12A and 12B, the outer diameter L <b> 10 of the path forming member 8 is larger than the outer diameter L <b> 8 of the external lead-side conductor 37.
As shown in FIG. 12B, the opening 811 provided in the path forming member 8 is provided to extend from the inner periphery beyond the outer diameter of the external lead-side conductor 37, but its end 812 is external. It is located between the outer diameter of the lead-side conductor 37 and the outer diameter of the path forming member 8.

  As shown in FIG. 13B, the path forming member 8 is provided so as to cover the external lead-side conductor 37 by bending a portion larger than the external lead-side conductor 37. The bent covering portion 813 is provided along the outer peripheral shape (circular shape) of the external lead-side conductor 37 so as to overlap each other to form irregularities like a crown for plugging a glass bottle.

A cylindrical external lead holding cylinder 6 is provided outside the path forming member 8 provided so as to cover the outer periphery of the external lead-side conductor 37 (upward in the drawing in FIG. 13B).
As shown in FIG. 14, a sealing tube 22 is provided in the outer peripheral direction of the discharge lamp 1 in FIG.

As described above, the opening 811 provided in the path forming member 8 is provided so as to extend at least to the outer periphery of the external lead-side conductor 37, so that the external lead-side conductor 37 and the conductive foil 35 shown in FIG. The space around the joint portion 94 (the portion where the joint portion 36 is provided) communicates with the external lead side space (not shown in FIG. 15, reference numeral 91 in FIG. 14).
Thus, the discharge lamp 1 is provided with the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37.

  Further, in the discharge lamp 1, the opening 811 of the path forming member 8 is a path 9 that communicates with the external lead side gap 91 and the conductive foil side gap 92, and thus faces the conductive foil side gap 92 in the conductive foil 35. An oxidation protection film 71 can also be provided on the surface.

  Thus, as in the second example of the path forming member 8, when the outer diameter is larger than the outer diameter of the external lead conductor 37, it extends to at least the outer periphery of the external lead-side conductor 37. By providing, the oxidation protection film 71 can be provided on at least the surface of the conductive foil 35 facing the external lead-side conductor 37.

  Moreover, when the end of the conductive foil 35 on the external lead side (the upper side of the conductive foil 35 in FIG. 15) is opposed to the sealing tube 22 as in the discharge lamp 1 according to the present invention, the lamp is turned on. At times, the conductive foil 35 may expand and come into contact with the sealing tube 22. At this time, since the end shape of the conductive foil 35 has an acute corner in the sealing tube 22, the sealing tube 22 may be damaged by being scratched. Therefore, in the discharge lamp 1 according to the fourth embodiment, as shown in FIG. 15, the end of the conductive foil 35 is covered with a foil-like path forming member 8, so that the bent path forming member 8 is electrically conductive foil. 35 and the sealing tube 22. As a result, the discharge lamp 1 according to the fourth embodiment prevents the end of the conductive foil 35 from directly contacting the sealing tube 22, thereby preventing the sealing tube 22 from being damaged by the conductive foil 35. be able to.

  From the above, the discharge lamp 1 according to the fourth embodiment has the path forming member provided with the opening 811 extending to at least the outer periphery 372 of the external lead-side conductor 37, whereby the second embodiment The same operation and effect as the discharge lamp 1 according to the above can be obtained.

The path forming member 8 included in the discharge lamp 1 according to the second to fourth embodiments is provided with an opening 811 for forming the path 9.
A discharge lamp 1 according to a fifth embodiment will be described with reference to FIG. 16 as an example in which the path 9 is formed without providing the opening 811. Also in the fifth embodiment, the sectional view of the discharge lamp 1 is not substantially different from that of FIGS. 1, 2 and 3A, so FIGS. .

FIG. 16A is a perspective view of the discharge lamp 1 of FIG. 2, and is an exploded view in which the sealing tube 22 is removed from the discharge lamp 1 of FIG. FIG. 16B is a diagram in which the path forming member 8 of FIG. 16A is interposed between the external lead-side conductor 37 and the external lead holding cylinder 6, and X in FIG. It is sectional drawing when it sees from a direction.
In FIG. 16, the same components as those shown in FIGS.

The discharge lamp 1 shown in FIG. 16 is different from the discharge lamp 1 shown in FIGS. 6 and 7 in that the path forming member 8 is not provided with an opening but is partially overlapped.
As an explanation of the discharge lamp 1 of FIG. 16, differences from the discharge lamp of FIGS. 6 and 7 will be described.

As shown in FIG. 16A, the substantially circular foil-shaped path forming member 8 is provided with a striking portion 816 where the wrinkles are gathered so as to continue from the inner periphery to the outer periphery.
When the path forming member 8 is interposed between the external lead side conductor 37 and the external lead holding cylinder 6 to complete the discharge lamp 1, the configuration shown in FIG.
FIG. 16B is a cross-sectional view of the path forming member 8 shown in FIG. For this reason, although not shown in FIG. 16B, the offset portion 816 continues in the depth direction of the drawing.

As shown in FIG. 16 (b), the substantially circular foil-shaped path forming member 8 that has gathered wrinkles is formed with a wrinkled portion 816 that overlaps three layers. A gap 375 is provided between the offset portion 816 of the path forming member 8 and the external lead-side conductor 37.
Since the striking portion 816 in the path forming member 8 is continuously provided so as to extend from the inner periphery to the outer periphery, the gap 375 also extends from the inner periphery to the outer periphery of the path forming member 8 along the striking portion 816. It is provided to extend to.

Further, on the side of the external lead holding cylinder 6, the external lead holding cylinder 6 bent toward the approaching portion 816 of the path forming member 8 and the approaching portion 816 of the path forming member 8 opposed thereto. An enclosed gap 61 is provided.
Since the striking part 816 in the path forming member 8 is continuously provided so as to extend from the inner periphery to the outer periphery, the gap 61 also extends from the inner periphery to the outer periphery of the path forming member 8 along the striking part 816. It is provided to extend to.

  These gaps 61 and 375 function as a path 9 that connects the external lead side gap 91 and the conductive foil side gap 92, and at least a surface of the conductive foil 35 that faces the external lead side conductor 37 (not shown in FIG. An oxidation protective film 71 can be provided on the reference numeral 351 in FIG.

  As shown in FIG. 16 (b), the overlapping portion at the offset portion 816 provided on the path forming member 8 is a convex portion and a concave portion between the external lead side conductor 37 and the external lead holding cylinder 6. Composed. A gap 61 is formed by the convex portion formed by the path forming member 8, and a gap 375 is formed by the concave portion. These gaps 61 and 675 are external lead side gaps (not shown in FIG. 16B, reference numeral 91 in FIG. 2). And a space 9 on the periphery of the joint (not shown in FIG. 16B, reference numeral 94 in FIG. 3A).

  From the above, the discharge lamp 1 according to the fifth embodiment includes the path forming member 8 provided with the striking portion 816 continuously from the inner periphery to the outer periphery, so that the discharge according to the second embodiment is performed. The same operation and effect as the lamp 1 can be obtained.

  Also, the path forming member 8 shown in FIG. 16B can be provided on the external lead-side conductor 37 having the bonding protrusion 371 as shown in FIG. In this case, the gaps 61 and 675 provided along the offset part 816 of the path forming member 8 are arranged so as to communicate the external lead side gap 91 and the gap 63 provided on the inner surface of the bonding projection 371. Thus, the external lead side gap 91 and the joint peripheral side gap 94 can be communicated with each other.

  As described above, in the discharge lamp 1 according to the fifth embodiment, the gaps 61 and 375 formed along the offset portion 816 have the external lead side gap (not shown in FIG. 16B), in FIG. It is only necessary to function as a path 9 that communicates the reference numeral 91) and the gap around the joint (not shown in FIG. 16B, reference numeral 94 in FIG. 3A). As shown in FIG. It is not necessary to provide the offset portion 816 that forms a uniform overlap from the inner periphery to the outer periphery of the member 8. For example, the circular foil-shaped path forming member 8 is made to have a large number of wrinkles, and the protrusions 816 formed by the wrinkles and the gaps 61 and 375 along the recesses communicate with each other. As a result, the external leads A path 9 in which the side gap (symbol 9 in FIG. 2) and the joint peripheral side gap (symbol 94 in FIG. 3A) communicate with each other may be formed.

  A sixth embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIG. Also in the sixth embodiment, since the sectional view of the discharge lamp 1 is not substantially different from that in FIGS. 1 to 3, FIGS. Moreover, since the position where the path | route formation member 8 of Fig.17 (a) is arrange | positioned is the same as the path | route formation member 8 shown in FIG. 6, FIG. 6 is also used as a reference figure.

FIG. 17A is an enlarged view of only the path forming member 8 shown in FIG. FIG. 17B is an enlarged view of a part of FIG. FIG. 17C is a cross-sectional view of FIG. FIG. 17D is a diagram in which FIG. 17C is interposed between the external lead-side conductor 37 and the external lead holding cylinder 6.
In FIG. 17, the same components as those shown in FIGS.

The path forming member 8 in FIG. 17A is different from the path forming member 8 shown in FIG. 7A in that it is configured by a network structure composed of a plurality of linear members.
As an explanation of the discharge lamp 1 according to the sixth embodiment having the path forming member 8 of FIG. 17A, differences from the discharge lamp 1 having the path forming member 8 of FIG. 7 will be described.

As shown in FIG. 1, a discharge lamp 1 according to a sixth embodiment has a discharge vessel 2, a foil seal structure for sealing the discharge vessel 2, and an opposed arrangement inside the sealed discharge lamp 2. A pair of electrodes 31 and 32 and a power feeding structure for feeding power to the pair of electrodes 31 and 32. The external lead holding cylinder 6 is provided on the outer periphery of the external lead 38 constituting the power feeding structure. Then, a path forming member 8 is provided between the external lead holding cylinder 6 and the external lead-side conductor 37 constituting the power feeding structure, and an oxidation protective film (see FIG. 1) is formed on the conductive foil 35 constituting the power feeding structure. Is provided with a notation (reference numeral 71) in FIG.
In particular, the discharge lamp 1 according to the sixth embodiment is characterized in that the path forming member 8 provided has a network structure composed of a plurality of linear members.

Description of the discharge lamp 1 in the sixth embodiment is omitted because the configuration of FIG. 6 and the size relationship of each member are the same.
The details of the path forming member 8 shown in FIG. 6 are the path forming member 8 shown in FIGS. 17 (a) to 17 (c).

As shown in FIGS. 17B and 17C, the path forming member 8 shown in FIG. 17A has a braided network structure by repeating a plurality of linear members alternately stacked. Constitute.
As shown in FIG. 17C, this network structure is configured such that the linear member repeatedly bends in the vertical direction of the drawing, and the other linear members overlap at the bent position.

  The path forming member 8 needs to have heat resistance in consideration of resistance heat transfer by the external lead-side conductor 37 and discharge heat transfer when the lamp is lit. For this reason, as the linear member constituting the path forming member 8, a refractory metal or an alloy made of a refractory metal is used. Specific examples of the refractory metal include molybdenum, tungsten, tantalum, ruthenium and rhenium.

When the discharge lamp 1 is completed by interposing the path forming member 8 having the network structure between the external lead-side conductor 37 and the external lead holding cylinder 6, heating by forming a foil seal structure or holding the external lead The structure shown in FIG. 17D is obtained by heating the cylinder 6 and the sealing tube 22.
As shown in FIGS. 17 (b) and 17 (c), the path forming member 8 made of a net-like structure is overlapped with a mountain portion where the linear members constituting the net-like structure are doubled and the linear members overlap. It is composed of a valley portion that is not. A gap 61 is provided between the valley portion and the external lead holding cylinder 6. Further, a gap 375 is provided between the external lead side conductor 37 and the valley portion of the path forming member 8 having a network structure.

As shown in FIG. 17B, the gaps 61 and 375 communicate with a mesh 821 surrounded by different linear members. Moreover, the path | route formation member 8 which has a mesh structure is comprised by the mesh structure from the inner periphery to the outer periphery.
For these reasons, the gaps 61 and 375 function as a path 9 that connects the external lead-side gap 91 and the conductive foil-side gap 92, and at least the surface of the conductive foil 35 that faces the external lead-side conductor 37 (see FIG. 2). An oxidation protection film 71 can be provided on a not-shown reference numeral 351 in FIG.

As described above, in order to provide the oxidation protection film 71 on at least the surface of the conductive foil 35 facing the external lead-side conductor 37 in the discharge lamp 1, the external lead-side gap 91 and the conductive foil-side gap 92 are communicated with each other. It is only necessary that the path forming member 8 is provided in the path forming member 8 and that the path 9 communicates with the external lead side gap 91 and the joint peripheral side gap 94 as a result.
For this reason, the network structure of the path forming member 8 is not necessarily limited to the double structure, and as a result of configuring the network structure, irregularities 822 are formed between the external lead side conductor 37 and the external lead holding cylinder 822. , 823 may be provided. In this case, the external lead holding cylinder 6 and the external lead-side conductor 37 are in contact with the convex portion 822 of the path forming member 8 having a network structure. Further, the recess 823 of the path forming member 8 having a net-like structure is provided with a gap 61 between the external lead holding cylinder 6 and a gap 375 between the external lead-side conductor 37, This functions as the route 9.

  The path forming member 8 constituted by the network structure of the discharge lamp 1 in the sixth embodiment is provided with a path 9 that allows the external lead side gap 91 and the joint peripheral side gap 94 to communicate with each other. It is the same as the path | route formation member 8 which has the opening part 811 of the discharge lamp 1 which concerns on an Example.

However, in the discharge lamp 1 according to the second embodiment, when the external lead-side conductor 37 and the external lead holding cylinder 6 are in close contact with each other via the path forming member 8, the external lead holding lamp is used for the following reason. The cylindrical body 6 and the sealing tube 22 that holds the cylindrical body 6 may be damaged.
In the discharge lamp 1 according to the second embodiment, when the lamp is lit, the conductive foil 35 is heated by resistance heat due to power feeding or heat transfer due to discharge, and the portion of the conductive foil 35 located in the conductive foil side gap 92 expands. The external lead-side conductor 37 joined to the conductive foil 35 may be moved toward the external lead holding cylinder 6 to press the external lead holding cylinder 6. Furthermore, the external lead-side conductor 37 itself expands due to resistance heat by power feeding or heat transfer by discharge, and presses the external lead holding cylinder 6.
The circular foil-shaped path forming member 8 interposed between the external lead side conductor 37 and the external lead holding cylinder 6 is expanded by heat transfer from the external lead side conductor 37. Normally, when the circular foil-shaped path forming member 8 is heated and expanded, it expands in the circumferential direction. However, since the path forming member 8 in the second embodiment is located between the external lead-side conductor 37 and the external lead holding cylinder 6, the path forming member 8 can be expanded in the circumferential direction. However, it is pressed toward the external lead holding cylinder 6 or the external lead side conductor 37.
As described above, in the discharge lamp 1 according to the second embodiment, when the lamp is lit, the external lead holding cylinder 6 is pressed, which becomes a stress on the external lead holding cylinder 6. Since the external lead holding cylinder 6 is made of a glass member, it has a problem of being damaged by this stress.

As shown in FIGS. 17A to 17C, the discharge lamp 1 according to the sixth embodiment has a braided network structure by repeating a plurality of linear members alternately stacked. For example, in the case of a net-like structure in which linear members are doubled, a valley portion (concave portion) 823 composed of a single linear member is formed around the double-capped mountain portion (convex portion) 822. Is done.
In the discharge lamp 1 according to the sixth embodiment, the path forming member 8 having a network structure is provided between the external lead-side conductor 37 and the external lead holding cylinder 6 so that the path is turned on when the lamp is lit. The peak portion 822 of the forming member 8 is pressed from the external lead side conductor 37 toward the external lead holding cylinder 6. At this time, since the valley portion 823 has little overlap of the linear members with respect to the peak portion 822, there is a gap that is not sandwiched between the external lead side conductor 37 and the external lead holding cylinder 6. Further, the mesh 821 having a mesh structure is not pressed by the external lead side conductor 37 and the external lead holding cylinder 6.
For this reason, when the lamp is lit, the linear member constituting the peak portion 822 expands due to the pressure applied to the peak portion 822 in the mesh structure constituting the path forming member 8, but the amount of expansion is the valley portion 823 or the mesh 821. And is allowed inside the path forming member 8 made of a net-like structure. That is, the path | route formation member 8 comprises elasticity by comprising a network structure.
As described above, the discharge lamp 1 according to the sixth embodiment is configured such that the path forming member 8 having a network structure is interposed between the external lead side conductor 37 and the external lead holding cylinder 6. It is possible to prevent the external lead holding cylinder 6 from being pressed during lighting.

  The path forming member 8 shown in FIG. 17A can also be provided on the external lead-side conductor 371 having the bonding projection 371 as shown in FIG. In this case, the gaps 61 and 375 provided along the network structure of the path forming member 8 are arranged so as to communicate the external lead side gap 91 and the gap 63 provided on the inner surface of the bonding projection 371. The external lead side gap 91 and the joint peripheral side gap 94 can be communicated with each other.

  From the above, the configuration and effects of the discharge lamp 1 according to the sixth embodiment can be summarized as follows.

As in the case of the discharge lamp 1 according to the second embodiment, the discharge lamp 1 according to the sixth embodiment is disposed outside the external lead-side conductor 37 and has the external lead 38 as in the features of the discharge lamp 1 according to the second embodiment. The discharge lamp 1 is provided with an external lead holding cylinder 6 between the outer lead 38 and the sealing tube 22, and is arranged between the external lead 38 and the external lead holding cylinder 6 in the longitudinal direction of the external lead 38. An external lead-side gap 91 is provided along the outer lead-side gap 91, and a path 9 is provided in which the external lead-side gap 91 and the joint portion 36 communicate with each other.
With this feature, in the discharge lamp 1 according to the sixth embodiment, the oxidation protection film 71 formation solution is applied to at least the surface of the conductive foil 35 that faces the external lead-side conductor 37 through the path 9, and the conductive foil 35 Oxidation of the surface 351 facing the external lead-side conductor 37 can be prevented.

Furthermore, in addition to the above features, the discharge lamp 1 according to the sixth embodiment forms a concave portion or / and a convex portion between the external lead side conductor 37 and the external lead holding cylinder 6. A path forming member 8 is provided.
Due to this feature, in the discharge lamp 1 according to the sixth embodiment, a path 9 is formed along the concave portion or / and the convex portion, and at least the external lead side conductor 37 in the conductive foil 35 is opposed to the path 9. Oxidation of the surface 351 facing the external lead side conductor 37 in the conductive foil 35 can be prevented by applying the oxidation protective film 71 formation solution to the surface 351 to be

Moreover, the discharge lamp 1 according to the sixth embodiment is characterized in that, in addition to the above features, the path forming member 8 is constituted by a network structure composed of a plurality of linear members.
Due to this feature, the discharge lamp 1 according to the sixth embodiment does not apply any stress to the external lead holding cylinder 6 and presses the external lead-side conductor 37 with a network structure. By allowing at 8, it is possible to prevent the external lead holding cylinder 6 from being damaged.

  A seventh embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIG. In the seventh embodiment as well, the sectional view of the discharge lamp 1 is not substantially different from those of FIGS. 1, 2, and 3A, and therefore, FIGS. 1, 2, and 3A are used as reference diagrams. .

18A is a perspective view of the discharge lamp 1 of FIG. 2, and is an exploded view in which the sealing tube 22 and the conductive foil 35 are removed from the discharge lamp 1 of FIG.
FIG. 18B shows the groove 374 of the external lead side conductive plate 37 in the discharge lamp 1 completed by providing a sealing tube (not shown in FIG. 18, reference numeral 22 in FIG. 2) in FIG. It is an expanded sectional view of the part which the outer lead holding cylinder 6 contacts.
In FIG. 18, the same components as those shown in FIGS.

The path 9 of the discharge lamp 1 in FIG. 18 is different from the path 9 of the discharge lamp 1 in FIG. 6 in that the path 9 is formed by a groove (concave portion) 374 provided in the external lead-side conductor 37.
As an explanation of the discharge lamp 1 in FIG. 17, differences from FIG. 6 will be described.

  As shown in FIG. 1, a discharge lamp 1 according to a seventh embodiment has a discharge vessel 2, a foil seal structure for sealing the discharge vessel 2, and an opposed arrangement inside the sealed discharge lamp 2. A pair of electrodes 31 and 32 and a power feeding structure for feeding power to the pair of electrodes 31 and 32. The external lead holding cylinder 6 is provided on the outer periphery of the external lead 38 constituting the power feeding structure. Then, a groove (concave portion) 374 is provided on a surface of the external lead side conductor 37 constituting the power supply structure facing the external lead holding cylinder 6, and an oxidation protection film (see FIG. 5) is formed on the conductive foil 35 constituting the power supply structure. 1 is provided with an unillustrated reference numeral 71) in FIG.

  Description of the discharge lamp 1 in FIG. 18A is omitted because the configuration in FIG. 6 and the size relationship of each member are the same.

The external lead side conductor 37 is provided with a groove (concave portion) 374 extending from the inner periphery to the outer periphery on the surface facing the external lead holding cylinder 6. The groove portion (concave portion) 374 of the external lead side conductor 37 is formed in a rectangular parallelepiped concave shape that is recessed with respect to a flat surface that is in contact with the external lead holding cylinder 6.
When the discharge lamp 1 is completed by bringing the external lead holding cylinder 6 into contact with the groove (recess) 374 of the external lead-side conductor 37, heating by forming a foil seal structure or the external lead holding cylinder The structure shown in FIG. 18B is obtained by heating the body 6 and the sealing tube 22.
The external lead holding cylinder 6 is bent with respect to the rectangular parallelepiped groove (recess) 374 in the external lead side conductor 37, whereby the external lead side conductor 37 groove (recess) 374 and the external lead holding A gap 61 is provided between the bent portion of the cylindrical body 6. Since the gap 61 is provided along the groove (concave portion) 374, the gap 61 is provided so as to extend from the inner periphery to the outer periphery of the external lead side conductor 37.

  In the discharge lamp 1 according to the first embodiment in which the path forming member 8 is not provided, as a method of generating the oxidation protective film 71 on at least the surface of the conductive foil 35 facing the external lead-side conductor 37, the above-described method is used. As described above, for example, a rubidium nitrate solution is dropped as an oxidation protective film 71 forming solution from the outside of the external lead side gap 91 (the entrance of the external lead side gap 91 above the plane of FIG. 2), and the external lead side conductivity in the conductive foil 35 is dropped. There is a method of applying the oxidation protective film 71 forming solution to the surface facing the body 37. At this time, the oxidation protective film 71 production solution passes between the external lead holding cylinder 6 and the external lead side conductor 37.

  However, as described in the description of the discharge lamp 1 according to the second embodiment, the external lead holding cylinder is located outside the external lead side conductor 37 (on the upper side of the paper in the external lead side conductor 37 in FIG. 2). When the body 6 is provided, the external lead-side conductor 37 and the external lead holding cylinder 6 are in close contact with each other, and the oxidation protection film 71 is formed on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37. There were times when it could not be provided.

  For this reason, the external lead-side conductor 37 of the discharge lamp 1 according to the seventh embodiment is a surface facing the external lead holding cylinder 6 and has a groove (concave portion) 374 extending from the inner periphery to the outer periphery. Is provided. In the discharge lamp 1 according to the seventh embodiment, when the foil seal structure is formed, the flat surface of the external lead side conductor 37 and the flat surface of the external lead holding cylinder 6 are in close contact with each other. ) The external lead holding cylinder 6 bends toward 374, but a gap 61 is provided between the bent surface and the groove (concave portion) 374 of the external lead side conductor 37.

When the external lead holding cylinder 6 is provided, in the heating step of welding the external lead holding cylinder 6 and the sealing tube 22, the heated external lead holding cylinder 6 is only softened. It is only slightly bent toward the groove (recess) 374 of the external lead side conductor 37. For this reason, the external lead holding cylinder 6 hardly fills the groove (concave portion) 374 of the external lead-side conductor 37 and the gap 61 is held.
Even if, in the heating step, the external lead holding cylinder 6 is softened or melted, the gap 61 between the groove portion (concave part) 374 of the external lead side conductor 37 and the external lead holding cylinder 6 is filled. The discharge lamp 1 is cooled to room temperature after the heating step, so that the discharge lamp 1 has a difference between the thermal expansion coefficient of the member constituting the external lead holding cylinder 6 and the thermal expansion coefficient of the member constituting the path forming member 8. A gap 61 is provided.
For the reason described above, a gap 61 is provided in the concave portion of the external lead-side conductor 37. The groove (recess) 374 of the external lead side conductor 37 is provided from the inner periphery to the outer periphery, thereby providing a gap 61 extending from the outer periphery of the external lead 38 to the outer periphery of the external lead side conductor 37. For this reason, the outer lead side conductor 37 communicates with the outer lead side gap 91 on the inner peripheral side. In addition, the outer lead side conductor 37 is connected to the conductive foil side gap 92 on the outer peripheral side.

  That is, in the external lead side conductor 37, a groove portion (concave portion) 374 that is a surface facing the external lead holding cylinder 6 and extends from the inner periphery to the outer periphery thereof is provided. The side gap 92 communicates with the side gap 92. Through the connected path 9, the conductive foil side gap 92 is filled with the oxidation protective film 71 forming solution dropped from the external lead side gap 91. At this time, there is a gap between the conductive foil 35 and the external lead side conductor 37, and the joint peripheral side gap 94 and the conductive foil side gap 92 communicate with each other. Since the oxidation protective film 71 forming solution is applied to the surface (not shown in FIG. 2, reference numeral 351 in FIG. 3A) facing the lead-side conductor 37, the discharge lamp 1 according to the seventh embodiment is The oxidation protection film 71 can be provided on at least the surface of the conductive foil 35 facing the external lead-side conductor 37 (not shown in FIG. 2, reference numeral 351 in FIG. 3A).

As described above, in the discharge lamp 1, in order to provide the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the external lead-side gap 91 and the conductive foil-side gap 92 are formed. A path 9 that communicates is provided in the external lead-side conductor 37, and the path 9 may eventually communicate with the external lead-side gap 91 and the joint peripheral-side gap 94.
For this reason, the groove (recess) 374 provided in the external lead-side conductor 37 is an example of a rectangular parallelepiped shape, and if it is a prismatic shape such as a triangular prism, the adjacent grooves constituting the groove (recess) 374 are formed. The formed surface forms a corner. Since the softened or melted external lead holding cylinder 6 cannot be filled in this corner, a gap 61 is formed at the position of this corner, and this functions as the path 9.
Further, since the path 9 provided in the external lead-side conductor 37 only needs to communicate the external lead-side gap 91 and the conductive foil-side gap 92, a groove (recess) 374 is formed in the entire radial direction of the external lead-side conductor 37. For example, the groove (concave portion) 374 located on the inner peripheral side of the external lead side conductor 37 may be provided at least from the inner peripheral position of the external lead holding cylinder 6. Further, the groove (concave portion) 374 located on the outer peripheral side of the external lead side conductor 37 is an external lead holder when the outer diameter of the external lead side conductor 37 is larger than the outer diameter of the external lead holder 6. It suffices to provide up to 6 outer peripheral positions. With this configuration, the groove (concave portion) 374 provided in the external lead side conductor 37 functions as a path 9 that connects the external lead side gap 91 and the conductive foil side gap 92.

  Furthermore, if the external lead-side conductor 37 is provided with a step such as a groove (concave portion) 374 with respect to a flat surface facing the external lead holding body 6, a path 9 is formed. Even if a convex portion is provided on the surface facing the external lead holding cylinder 6 so as to form a step, a gap can be provided between the external lead holding cylinder 6 and the external lead holding cylinder 6.

  Note that the groove (concave portion) 374 provided in the external lead side conductor 37 shown in FIG. 18A can also be provided in the external lead side conductor 37 having the bonding projection 371 as shown in FIG. In this case, the gap 61 provided along the groove (recess) 374 is provided so as to communicate the external lead-side gap 91 and the gap 63 provided on the inner surface of the bonding projection 371, so that the external lead-side gap is provided. 91 and the joint peripheral side gap 94 can be communicated with each other.

  From the above, the configuration and effects of the discharge lamp 1 according to the seventh embodiment can be summarized as follows.

The discharge lamp 1 according to the seventh embodiment is similar to the discharge lamp 1 according to the second embodiment in that the discharge lamp 1 is outside the external lead-side conductor 37 and the external lead 38. The discharge lamp 1 is provided with an external lead holding cylinder 6 between the outer lead 38 and the sealing tube 22, and the longitudinal direction of the external lead 38 is between the external lead 38 and the external lead holding cylinder 6. The external lead-side gap 91 is provided along the outer lead-side gap 91, and the path 9 is provided to connect the external lead-side gap 91 and the joint portion 36.
With this feature, in the discharge lamp 1 according to the seventh embodiment, the oxidation protection film 71 forming solution is applied to at least the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37 via the path 9. It is possible to prevent oxidation of the surface 351 facing the external lead-side conductor 37 at 35.

Furthermore, in addition to the above features, the discharge lamp 1 according to the seventh embodiment has a path that forms a concave portion or / and a convex portion between the external lead side conductor 37 and the external lead holding cylinder 6. By providing the forming member 8, the path 9 is configured.
Due to this feature, in the discharge lamp 1 according to the seventh embodiment, a path 9 is formed along the concave portion or / and the convex portion, and at least the external lead side conductor 37 in the conductive foil 35 is opposed to the path 9. The surface of the surface 351 is coated with the oxidation protective film 71 forming solution, so that the surface 351 of the conductive foil 35 facing the external lead-side conductor 37 can be prevented from being oxidized.

  A discharge lamp 1 of an eighth embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIGS. 19 and 20. In the eighth embodiment as well, the sectional view of the discharge lamp 1 is not substantially different from that in FIGS. 1 and 2, and therefore FIGS. 1 and 2 are used as reference diagrams.

FIG. 19A is a perspective view of the discharge lamp 1 of FIG. 2, and is an exploded view in which the sealing tube 22 is removed from the discharge lamp 1 of FIG. FIG. 19B is a top view seen from the end portion of the external lead 38 in FIG. FIG. 19C is an enlarged view of a portion surrounded by a dotted circle in FIG.
20A is abutted via a conductive foil 35 in the discharge lamp 1 completed by providing the sealing tube in FIG. 19 (not shown in FIG. 20A, reference numeral 22 in FIG. 2). 7 is an enlarged cross-sectional view of a portion where an external lead side conductor 37 and an external lead holding cylinder 6 are in contact with each other. FIG. FIG. 20B is an enlarged view of a portion surrounded by a dotted circle in the discharge lamp 1 of FIG.
In FIGS. 19 and 20, the same components as those shown in FIGS.

The path 9 of the discharge lamp 1 in FIG. 19 is configured along the conductive foil 35 by providing the conductive foil 35 from the outer periphery of the external lead-side conductor 37 to the outer periphery of the external lead 38. This is different from the path 9 of the discharge lamp 1 in FIG.
As an explanation of the discharge lamp 1 in FIG. 19, differences from FIG. 6 will be described.

  As shown in FIG. 1, the discharge lamp 1 according to the eighth embodiment has a discharge vessel 2, a foil seal structure that seals the discharge vessel 2, and an opposed arrangement inside the sealed discharge lamp 2. A pair of electrodes 31 and 32 and a power feeding structure for feeding power to the pair of electrodes 31 and 32. The external lead holding cylinder 6 is provided on the outer periphery of the external lead 38 constituting the power feeding structure. Thus, the conductive foil 35 constituting the power supply structure is provided so as to extend from the outer periphery to the inner periphery of the external lead side conductor 37, and the extended portion of the conductive foil 35 is provided with the external lead side conductor 37 and the external lead holding cylinder. An oxidation protective film (not shown in FIG. 1, reference numeral 71 in FIG. 3) is provided on at least the surface of the conductive foil 35 constituting the power supply structure that faces the external lead-side conductor 37. It is characterized by that.

  Since the discharge lamp 1 in FIG. 19A has the same configuration as FIG.

  A plurality of conductive foils 35 (four conductive foils 35 in FIG. 18) are provided apart from each other along the outer peripheral surface in the central axis direction of the sealing insulator 5. The plurality of conductive foils 35 are electrically connected to the outer peripheral surface of the disk-shaped external lead-side conductor 37 by welding or the like. Further, the conductive foil 35 is provided so as to be bent from the outer peripheral surface of the external lead side conductor 37 and extend to the outer periphery of the external lead 38 as shown in FIG. A portion of the conductive foil 35 extending from the outer peripheral surface of the external lead side conductor 37 to the outer periphery of the external lead 38 is interposed between the external lead side conductor 37 and the external lead holding cylinder 6.

  In the discharge lamp 1 according to the first embodiment in which the path forming member 8 is not provided, as a method for generating the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the above-described method is used. As shown in FIG. 2, for example, a rubidium nitrate solution is dropped from the outside of the external lead side gap 91 (the entrance of the external lead side gap 91 above the paper surface in FIG. 2) as an oxidation protective film 71 formation solution, and the external foil side in the conductive foil 35 There is a method of applying a solution for forming the oxidation protective film 71 on the surface facing the conductor 37. At this time, the oxidation protection film 71 generation solution passes between the external lead side holding cylinder 6 and the external lead side conductor 37.

  However, as described in the description of the discharge lamp 1 according to the second embodiment, the external lead holding cylinder is located outside the external lead side conductor 37 (on the upper side of the paper in the external lead side conductor 37 in FIG. 2). When the body 6 is provided, the external lead-side conductor 37 and the external lead holding cylinder 6 are in close contact with each other, and the oxidation protection film 71 is formed on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37. There were times when it could not be provided.

  Therefore, in the discharge lamp 1 according to the eighth embodiment, the conductive foil 35 is extended from the outer periphery of the external lead side conductor 37 to the outer periphery of the external lead 38, and this conductive foil 35 is extended to the external lead side conductor 37 and the external lead. It was interposed between the holding cylinder 6. At this time, a step corresponding to the thickness of the conductive foil 35 is provided on the flat surface of the external lead-side conductor 37 facing the external lead holding cylinder 6 as shown in FIG. For this reason, a gap 61 surrounded by the bent surface of the external lead holding cylinder 6 facing the flat surface of the external lead side conductor 37 and the side surface of the conductive foil 35 corresponding to the thickness is provided.

When the external lead holding cylinder 6 is provided, in the heating step of welding the external lead holding cylinder 6 and the sealing tube 22, the heated external lead holding cylinder 6 is only softened. It only bends toward the flat surface of the external lead-side conductor 37 and the side surface due to the thickness of the conductive foil 35. Therefore, the external lead holding cylinder 6 hardly fills the gap 61 between the flat surface of the external lead-side conductor 37 and the side surface due to the thickness of the conductive foil 35, and the gap 61 is held.
Temporarily, in the heating step, the gap 61 between the flat surface of the external lead-side conductor 37 and the side surface due to the thickness of the conductive foil 35 and the external lead holding cylinder 6 facing this is softened or melted. Even if the external lead holding cylinder 6 is filled, the discharge lamp 1 is cooled to room temperature after the heating step, so that the discharge lamp 1 has the coefficient of thermal expansion of the members constituting the external lead holding cylinder 6 and the path forming member 8. A gap 61 is provided due to a difference from the constituent members.
For the above-described reason, by providing the conductive foil 35 on the flat surface of the external lead-side conductor 37, a gap is provided on the side surface corresponding to the thickness of the conductive foil 35. For this reason, by providing the conductive foil 35 between the external lead side conductor 37 and the external lead holding cylinder 6 and from the outer periphery of the external lead side conductor 37 to the outer periphery of the external lead 38, The gap 61 is provided along the side surface of the portion of the conductive foil 35 located between the external lead side conductor 37 and the external lead holding cylinder 6. As a result, the conductive foil 35 communicates with the external lead side gap 93 on the external lead 38 side. The conductive foil 35 communicates with the conductive foil side gap 92 on the outer peripheral side of the external lead side conductor 37.

  That is, by providing a conductive foil 35 between the external lead side conductor 37 and the external lead holding cylinder 6 and extending from the outer periphery of the external lead side conductor 37 to the outer periphery of the external lead 38, the external lead side The air gap 91 and the conductive foil side air gap 92 communicate with each other. Through the connected path 9, the conductive foil side gap 92 is filled with the oxidation protective film 71 forming solution dropped from the external lead side gap 91. At this time, there is a joint peripheral side gap 94 between the conductive foil 35 and the external lead side conductor 37, and the joint peripheral side gap 94 and the conductive foil side gap 92 communicate with each other. Since the oxidation protection film 71 forming solution is applied to the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the discharge lamp 1 according to the fifth embodiment has at least the external lead-side conductor in the conductive foil 35. An oxidation protection film 71 can be provided on the surface 351 facing the surface 37.

  Furthermore, since the oxidation protective film 71 production solution is also applied to the side surface of the conductive foil 35 constituting the path 9 between the external lead side conductor 37 and the external lead holding cylinder 6, This portion is also provided with an oxidation protection film (reference numeral 71 in FIG. 20A). Moreover, since the oxidation protection film 71 production | generation solution is also filled also into the conductive foil side space | gap 92, the surface which opposes the conductive foil side space | gap 92 in the conductive foil 35 is also provided with the oxidation protection film (reference numeral 71 in FIG. 20B). ) Is provided.

As described above, in the discharge lamp 1, in order to provide the oxidation protective film 71 on at least the surface of the conductive foil 35 facing the external lead side conductor 37, the external lead side gap 91 and the joint peripheral side gap 94 are formed. The communicating path 9 may be constituted by the conductive foil 35 provided between the external lead side conductor 37 and the external lead holding cylinder 6.
For this reason, the conductive foil 35 provided between the external lead side conductor 37 and the external lead holding cylinder 6 does not need to be provided with the end portion of the conductive foil 35 to the outer periphery of the external lead 38, and the external lead side gap 91 is formed. If the internal lead surface 6 of the external lead holding cylinder 6 is provided, the external lead side gap 91 and the conductive foil side gap 92 can be communicated with each other.

As described above, as in the discharge lamp 1 according to the first embodiment, the end of the conductive foil 35 on the side of the external lead 38 (the upper side of the conductive foil 35 in FIG. 15) faces the sealing tube 22. In the discharge lamp 1, the conductive foil 35 may expand and come into contact with the sealing tube 22 when the lamp is lit. At this time, since the end shape of the conductive foil 35 has an acute corner in the sealing tube 22, the sealing tube 22 may be damaged by being scratched.
Therefore, in the discharge lamp 1 according to the eighth embodiment, the conductive foil 35 is bent at the outer periphery of the external lead-side conductor 37, and the end of the conductive foil 35 is disposed opposite to the outer periphery of the external lead 38. A bent portion of the conductive foil 35 is opposed to the sealing tube 22. Since the bent portion in the conductive foil 35 does not have an acute angle like the end portion of the conductive foil 35, the sealing tube 22 can be prevented from being damaged.

  From the above, the configuration and effects of the discharge lamp 1 according to the eighth embodiment can be summarized as follows.

The discharge lamp 1 according to the eighth embodiment is similar to the discharge lamp 1 according to the second embodiment in that the discharge lamp 1 is outside the external lead side conductor 37 and the external lead 38. The discharge lamp 1 is provided with an external lead holding cylinder 6 between the outer lead 38 and the sealing tube 22, and is arranged between the external lead 38 and the external lead holding cylinder 6 in the longitudinal direction of the external lead 38. An external lead-side gap 91 is provided along the outer lead-side gap 91, and a path 9 is provided in which the external lead-side gap 91 and the joint portion 36 communicate with each other.
With this feature, in the discharge lamp 1 according to the eighth embodiment, the oxidation protection film 71 forming solution is applied to at least the surface of the conductive foil 35 that faces the external lead-side conductor 37 via the path 9, and the conductive foil 35. Oxidation of the surface 351 facing the external lead-side conductor 37 can be prevented.

Furthermore, in addition to the above features, the discharge lamp 1 according to the eighth embodiment has an outer surface of the external lead side conductor 37 between the external lead side conductor 37 and the external lead holding cylinder 6. The conductive foil 35 is provided so as to be continuous with the inner surface of the external lead holding cylinder 6.
With this feature, in the discharge lamp 1 according to the fifth embodiment, a path 9 is formed along the conductive foil 35 positioned between the external lead side conductor 37 and the external lead holding cylinder 6, and this path 9 is applied to at least the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37 to prevent oxidation 351 on the surface of the conductive foil 35 that faces the external lead-side conductor 37. can do.

  A ninth embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIGS. In the ninth embodiment as well, since the sectional view of the discharge lamp 1 is not substantially different from that in FIG. 1, FIG. 1 is used as a reference diagram.

FIG. 21A is an enlarged cross-sectional view of one discharge tube 1 in FIG. 1 on the side of one sealing tube 22 (the sealing tube 22 on the upper side in FIG. 1). FIG. 21B is an enlarged view of a portion surrounded by a dotted circle in the discharge lamp 1 of FIG. FIG. 22A is a perspective view of the discharge lamp 1 of FIG. 21A, and is an exploded view before the sealing tube 22 is provided in the discharge lamp 1 of FIG. FIG. 22B is a view showing only the external lead-side conductor 37 in FIG. 22A and is a top view for explaining the through hole 373 of the external lead-side conductor 37.
21 and 22, the same components as those illustrated in FIGS. 1 to 3 are denoted by the same reference numerals.

The discharge lamp 1 shown in FIGS. 21 and 22 is provided with a groove 381 extending along the longitudinal direction on the outer peripheral surface of the external lead 38, and a through hole along the central axis direction on the inner peripheral surface of the external lead-side conductor 37. It differs from the discharge lamp 1 of FIGS.
As an explanation of FIGS. 21 and 22, differences from FIGS.

  As shown in FIG. 1, a discharge lamp 1 according to a ninth embodiment includes a discharge vessel 2, a foil seal structure that seals the discharge vessel 2, and an opposed arrangement inside the sealed discharge lamp 1. A pair of electrodes 31 and 32 and a power feeding structure for feeding power to the pair of electrodes 31 and 32. The external lead holding cylinder 6 is provided on the outer periphery of the external lead 38 constituting the power feeding structure. Then, an oxidation protective film (not shown in FIG. 1, reference numeral 71 in FIG. 21B) is provided on the conductive foil 35 constituting this power feeding structure, and a groove (see FIG. 1) is formed in the external lead 38 constituting this power feeding structure. Is provided (not shown, reference numeral 381 in FIG. 21 (a)), and a through hole (not shown in FIG. 1, reference numeral 373 in FIG. 21 (a)) is provided in the external lead side conductor 37 constituting this power feeding structure. It is characterized by that.

  Description of the discharge lamp 1 in FIG. 22A is omitted because the configuration in FIG. 6 and the size relationship of each member are the same.

In order to prevent these weldings between the external lead-side conductor 37 and the external lead holding cylinder 6 constituting the power supply structure, for example, a circular foil-like welding preventing body made of molybdenum is provided.
As a member constituting the welding preventive body, since it is necessary to have heat resistance, a refractory metal or an alloy made of a refractory metal is used. Examples of the refractory metal include molybdenum, tungsten, tantalum, ruthenium and rhenium.
Further, since the welding prevention body is located between the external lead-side conductor 37 and the external lead holding cylinder 6, the external lead holding cylinder 6 even if expanded due to the heat generated by the discharge when the lamp is lit. Since it is calculated | required not to press, it is preferable that it is foil shape. For this reason, molybdenum which is easy to process so as to reduce the thickness among the above-mentioned refractory metals is preferably used.

  Further, a sealing insulator-side gap 93 extending in the radial direction from the outer periphery of the external lead 38 is provided between the external lead-side conductor 37 constituting the power feeding structure and the sealing insulator 5 constituting the foil seal structure. Is provided.

As shown in FIGS. 21A and 22A, the outer lead 38 is provided with a semi-cylindrical groove 381 extending along the longitudinal direction on the outer peripheral surface thereof.
As shown in FIG. 21B, the external lead-side conductor 37 is provided with a cylindrical lead hole 376 for inserting the external lead 38 through the central axis thereof. Further, a through hole 373 having an outer diameter smaller than the outer diameter of the lead hole 376 (that is, the inner diameter L6 of the external lead side conductor 37) is provided on the inner peripheral surface of the outer lead side conductor 37 (see FIG. 21 (b)).

  The groove 381 in the external lead 38 and the through hole 373 in the external lead side conductor 37 are used for sealing between the external lead side conductor 37 and the sealing insulator 5 as shown in FIG. This is a path 9 that connects the insulator-side gap 93 and the external lead-side gap 91.

  In the discharge lamp 1 according to the first embodiment in which the path forming member 8 is not provided, as described above, as a method of generating an oxidation protective film on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor, For example, a rubidium nitrate solution is dropped from the outside of the external lead side gap 91 (the entrance of the external lead side gap 91 above the paper surface in FIG. 2) as the oxidation protective film 71 formation solution, and the external lead side conductor in the conductive foil 35 is dropped. There is a method of applying a solution for forming the oxidation protective film 71 to the surface 351 facing the surface 37. At this time, the oxidation protective film 71 forming solution passes between the external lead side holding cylinder 6 and the external lead side conductor 37.

  However, as described in the description of the discharge lamp 1 according to the second embodiment, the external lead holding cylinder is located outside the external lead side conductor 37 (on the upper side of the paper in the external lead side conductor 37 in FIG. 2). When the body 6 is provided, the external lead-side conductor 37 and the external lead holding cylinder 6 are in close contact with each other, and the oxidation protection film 71 is formed on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37. There were times when it could not be provided.

  When the external lead side conductor 37 and the external lead holding cylinder 6 are in close contact, the external lead side conductor 37 joined to the expanding conductive foil 35 moves toward the external lead holding cylinder 6. Accordingly, a sealing insulator-side gap 93 is formed between the external lead-side conductor 37 and the sealing insulator 5.

  For this reason, the discharge lamp 1 according to the ninth embodiment uses the sealing insulator-side gap 93 to provide the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 that faces the external lead-side conductor 37. It is provided.

Specifically, in order to allow the external lead side gap 91 and the sealing insulator side gap 93 to communicate with each other, a groove 381 is provided on the outer peripheral surface of the external lead 38 on the surface facing the external lead side conductor 37, and the external lead A through hole 373 is provided on the inner peripheral surface of the side conductor 37 on the surface facing the external lead 38.
As a result, the oxidation protective film 71 forming solution dropped from the outside of the external lead-side gap 91 passes through the groove 381 of the external lead 38 and the through-hole 373 of the external lead-side conductor 37, and the sealing insulator-side gap The conductive foil side gap 92 is filled through 93. At this time, there is a joint peripheral side gap 94 between the conductive foil 35 and the external lead side conductor 37, and the joint peripheral side gap 94 and the conductive foil side gap 92 communicate with each other. Since the oxidation protection film 71 forming solution is applied to the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the discharge lamp 1 according to the ninth embodiment has at least the external lead-side conductor in the conductive foil 35. An oxidation protection film 71 can be provided on the surface 351 facing the surface 37.

  Furthermore, since the oxidation protection film 71 forming solution is also filled in the conductive foil side gap 92, the oxidation protection film 71 is also provided on the surface of the conductive foil 35 that faces the conductive foil side gap 92.

As described above, in the discharge lamp 1, in order to provide the oxidation protection film 71 on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37, the external lead-side gap 91 and the sealing insulator-side gap 93 are provided. It is sufficient to provide a path 9 that communicates with each other.
For this reason, the path 9 includes a groove 381 provided on the surface of the external lead 38 facing the external lead-side conductor 37 and a through hole 373 provided on the surface of the external lead-side conductor 37 facing the external lead 38. Any of these may be provided.
Further, as shown in FIG. 22A, the groove 381 provided in the external lead 38 is provided along the longitudinal direction of the external lead 38. However, the external lead side conductor side gap 91 and the sealing insulator side gap 93 are provided. In order to communicate with each other, a groove 381 may be provided at least on the surface facing the external lead-side conductor 37 in the longitudinal direction of the external lead 38.

  In the case where the welding prevention body shown in FIG. 22 (a) is provided, the external lead 38 is used when the welding prevention body prevents the external lead side gap 91 and the sealing insulator side gap 93 from communicating with each other. In the longitudinal direction, it is preferable to provide the groove 381 on at least the surface facing the welding preventing body.

  Further, the groove 381 of the external lead 38 and the through hole 373 of the external lead-side conductor 37 shown in the ninth embodiment are provided in the external lead-side conductor 37 having the joining protrusion 371 as shown in FIG. You can also.

  From the above, the configuration and effects of the discharge lamp 1 according to the ninth embodiment can be summarized as follows.

In the discharge lamp 1 according to the ninth embodiment, the discharge lamp 1 is outside the external lead-side conductor 37, and the external lead holding cylinder is provided between the external lead 38 and the sealing tube 22. The discharge lamp 1 is provided with an external lead side gap 91 along the longitudinal direction of the external lead 38 between the external lead 38 and the external lead holding cylinder 6, and the external lead side gap A path 9 is provided in which 91 and the joint portion 36 communicate with each other.
With this feature, in the discharge lamp 1 according to the ninth embodiment, the oxidation protection film 71 forming solution is applied to at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37 via the path 9, It is possible to prevent oxidation of the surface 351 facing the external lead-side conductor 37 at 35.

Further, the discharge lamp 1 according to the ninth embodiment is provided with a sealing insulator-side gap 93 between the external lead-side conductor 37 and the sealing insulator 5 in addition to the above features, The external lead side conductor 37 is provided with a through hole 373 and / or a groove 381 in the external lead 38 so that the lead side gap 91 and the sealing insulator side gap 93 communicate with each other, and the sealing insulator side The gap 93 and the through-hole 373 or / and the groove 381 constitute the path 9.
Due to this feature, the discharge lamp 1 according to the ninth embodiment has a through-hole 373 provided in the external lead-side conductor 37 and / or a groove 381 provided in the external lead and a sealing insulator-side gap 93. Then, at least the surface of the conductive foil 35 facing the external lead-side conductor 37 is coated with the oxidation protection film 71 forming solution, and the surface 351 of the conductive foil 35 facing the external lead-side conductor 37 can be prevented from being oxidized. .

In the discharge lamp 1 according to the first embodiment described with reference to FIGS. 1 to 5, it is described that the oxidation protection film 71 is provided on at least the surface 351 of the conductive foil 35 facing the external lead-side conductor 37. Further, the discharge lamp 1 according to the second to ninth embodiments is provided with a path 9 in which the external lead-side gap 91 and the joint 36 are communicated with the configuration of the discharge lamp 1 according to the first embodiment. Is shown.
Subsequently, the discharge lamp 1 according to the tenth embodiment configured to be added to the discharge lamp 1 according to the first to ninth embodiments as means for restricting the inflow of air into the conductive foil side gap 92 will be described below. As shown.

  A tenth embodiment of the discharge lamp 1 according to the present invention will be described with reference to FIG.

FIG. 23 is an enlarged cross-sectional view on the side of one sealing tube 22 in the discharge lamp 1.
In FIG. 22, the same components as those shown in FIGS.

The discharge lamp 1 shown in FIG. 23 is different from the discharge lamp shown in FIGS.
As an explanation of FIG. 23, differences from FIGS.

  As shown in FIG. 23, an external lead-side gap 91 is provided between the external lead 38 and the external lead holding cylinder 6. The external lead holding cylinder 6 and the external side are arranged outside the external lead holding cylinder 6 (above the paper surface of the external lead holding cylinder 6 in FIG. 23) so as to cover the external lead side gap 91. A low melting glass 72 is filled between the leads 38.

  The low melting point glass 72 contains boron oxide and bismuth oxide as main components, and the total weight of the main components is 70% or more of the total weight. Moreover, the DTA transition temperature in the differential thermal analysis (DTA) is in the range of 370 to 550 ° C. Note that the DTA transition temperature of the low-melting glass 72 varies depending on the composition ratio of boron oxide and bismuth oxide, and usually the melting point increases as the DTA transition temperature increases.

In the discharge lamps 1 in the first to ninth embodiments, the external lead-side gap 91 and the conductive foil-side gap 92 communicate with each other. Since air flows into the lead-side gap 91, if there is a portion of the conductive foil 35 where the oxidation protection film 71 is not provided, that portion is exposed to the air.
For this reason, as shown in FIG. 23, by providing the low melting point glass 72 so as to cover the external lead side gap 91, air flow into the conductive foil side gap 92 is restricted, and oxidation by the conductive foil 35 is suppressed. can do.

  23 can be applied to any of the discharge lamps 2 according to the first to ninth embodiments.

The discharge lamp 2 of the tenth embodiment is added to any of the discharge lamps 2 according to the first to ninth embodiments, so that in addition to the features of each embodiment, the external lead 38 and the external lead holding A low melting point glass 72 is provided between the cylinder 6 for use.
Due to this feature, the discharge lamp 1 of the tenth embodiment suppresses the inflow of air into the gap outside the conductive foil 35 and suppresses the oxidation of the portion of the conductive foil 35 where the oxidation protection film 71 is not generated. can do.

It is explanatory drawing of the 1st Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 1st Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 1st Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 1st Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 1st Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 2nd Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 2nd Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 2nd Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 2nd Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 3rd Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 3rd Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 4th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 4th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 4th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 4th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 5th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 6th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 7th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 8th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 8th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 9th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 9th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the 10th Example of the discharge lamp which concerns on this invention. It is explanatory drawing of the discharge lamp which concerns on the past. It is explanatory drawing of the discharge lamp which concerns on the past. It is explanatory drawing of the discharge lamp which concerns on the past.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Discharge lamp 2 Discharge vessel 21 Arc tube 22 Sealing tube 31 Anode 32 Cathode 33 Internal lead 34 Internal lead side conductor 35 Conductive foil 351 Surface 36 facing the conductor in the conductive foil 36 Joint part 37 External lead side conductor 371 Join Protruding portion 372 Outer peripheral surface 373 Through hole 374 Groove portion 375 Clearance 376 Lead hole portion 38 External lead 381 Conductor side groove portion 382 Outer peripheral surface 4 Internal lead holding cylinder 5 Sealing insulator 51 Lead concave portion 6 External lead holding Cylinder 61 gap 62 inner peripheral surface (external lead holding hole)
63 Crevice 71 Oxidation protection film 72 Low melting point glass 8 Path forming member 81 Foil 811 Opening portion 812 Opening end portion 813 Bending covering portion 814 First taper 815 Second taper 816 Offset portion 82 Network structure 821 Mesh 822 Mountain (convex)
823 Valley part (concave part)
9 Path 91 External lead side gap 92 Conductive foil side gap 93 Sealing insulator side gap

L1 Region L2 facing the conductor in the axial direction of the disk-shaped conductor L2 Region facing the conductor in the circumferential direction of the disk-shaped conductor L3 Outer diameter L4 of the outer lead L5 Inner diameter L5 of the outer lead holding cylinder Holding tube outer diameter L6 Conductive foil inner diameter L7 Conductive foil outer diameter L8 External lead side conductor outer diameter L9 External lead side conductor inner diameter L10 Conductive foil outer diameter

A atmosphere

Claims (10)

A discharge vessel comprising a light emitting tube having a light emitting space inside and a sealing tube connected to both ends thereof;
A sealing insulator provided inside the sealing tube;
An electrode disposed oppositely on the arc tube side inside the discharge vessel;
A conductive foil electrically connected to the electrode and provided between the sealing tube and the sealing insulator;
A conductor that is electrically connected to the conductive foil via a joint and is provided outside the sealing insulator;
An external lead electrically connected to the conductor;
In a discharge lamp consisting of
A discharge lamp characterized in that an oxidation protective film made of rubidium / molybdenum double oxide is provided at least on the surface of the conductive foil facing the conductor. The discharge lamp is an outer side of the conductor and a discharge lamp provided with an external lead holding cylinder between the external lead and the sealing tube,
An external lead side gap is provided between the external lead and the external lead holding cylinder along the longitudinal direction of the external lead,
The discharge lamp according to claim 1 , wherein a path is provided in which the external lead-side gap communicates with the joint. 3. The discharge according to claim 2 , wherein the path is configured by providing a path forming member that forms a concave portion or / and a convex portion between the conductor and the external lead holding cylinder. 4. lamp. The discharge lamp according to claim 3 , wherein the path forming member is provided with an opening continuous from the inner surface of the external lead holding cylinder to the outer surface of the conductor. The discharge lamp according to claim 3 , wherein the path forming member is provided with a striking portion that continues from the inner surface of the external lead holding cylinder to the outer surface of the conductor. The discharge lamp according to claim 3 , wherein the path forming member is configured by a network structure including a plurality of linear members. The discharge lamp according to claim 2 , wherein the path is configured by providing a concave portion or / and a convex portion in the conductor. To claim 2, characterized in that a conductor foil so as to be continuous to the inner surface of the external lead cylindrical retaining body from the outer surface of the conductive member between the conductor collector and the external lead cylindrical retaining member The described discharge lamp. A sealing insulator-side gap is provided between the conductor and the sealing insulator,
A through hole or / and a groove in the external lead are provided in the conductor so as to communicate the external lead side gap and the sealing insulator side gap.
The discharge lamp according to claim 2 or 3 , wherein the sealing insulator side gap and the through hole or / and the groove portion constitute the path. The discharge lamp according to claim 2 , wherein a low melting point glass is provided between the external lead and the external lead holding cylinder.

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