JP2008084815A - High-pressure discharge lamp, method of manufacturing high-pressure discharge lamp and lighting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp which can accommodate a light emitting tube made of a translucent ceramic in an external tube and can seal the outer tube as well even if the outer tube is minimized. <P>SOLUTION: The high-pressure discharge lamp HDL is composed of an arc tube IT provided with a translucent ceramic airtight container 1, a pair of electrodes 2, 2, arranged facing with each other and sealed in the container, a discharging medium, and a current introducing conductor 3 which is introduced airtight in the translucent ceramic airtight container and connected with the electrodes and an outer tube OT, which is provided with a current supplying conductor 7 having a sliding connection part 7c which is introduced inside airtight and works in an axial direction, and which accommodates the arc tube in a condition that the current introducing conductor is connected capable of sliding in the axial direction with the sliding connection part of the current supplying conductor and is maintained airtight against an external atmosphere. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a high-pressure discharge lamp including a light-transmitting hermetic container made of a light-transmitting ceramic, a manufacturing method thereof, and an illumination device including the high-pressure discharge lamp.

  A high-pressure discharge lamp including a light-transmitting hermetic container made of a light-transmitting ceramic is known (for example, see Patent Document 1). In Patent Document 1, in order to obtain a ceramic metal halide lamp for a liquid crystal backlight with a linear transmittance of translucent ceramics of 60 to 85%, crystals having an average particle diameter of 5 μm or less are placed in a translucent ceramic discharge vessel. Polycrystalline yttrium aluminum garnet (YAG) made of

  In order to seal a translucent airtight container using translucent ceramics, frit glass is generally used. In order to seal with a frit glass having lower heat resistance than translucent ceramics, a small-diameter cylindrical portion extending from both ends of the translucent discharge vessel is formed and sealed at the end of the small-diameter cylindrical portion. . Then, a small gap called a capillary is formed between the electrode shaft portion and the inner surface of the small diameter cylindrical portion inside the small diameter cylindrical portion, thereby generating a temperature gradient, thereby reducing the temperature of the sealing portion. Yes.

  When the arc tube is made of translucent ceramics, the inside of the outer tube that houses the arc tube is kept in a vacuum to prevent oxidation of current-introducing conductors made of oxidizable metals such as niobium Or the temperature at the coldest part of the arc tube can be increased as desired. In the latter case, by increasing the coldest part temperature, the light emission efficiency can be increased as compared with the case of using a light-transmitting airtight container made of quartz glass. In addition, when encapsulating a halogen of a low melting point metal such as zinc as a lamp voltage forming medium instead of mercury, the vapor pressure of the halide increases by increasing the coldest part temperature of the arc tube, The lamp voltage can be further increased. Note that an inert gas can be sealed in the outer tube at a predetermined pressure as desired.

  Moreover, even if it is the arc_tube | light_emitting_tube using translucent ceramics, generally an outer tube is formed using glass, such as hard glass, quartz glass, or soft glass.

JP-A-10-255719

  However, in the case of a high pressure discharge lamp for an automobile headlamp or the like, when the entire lamp is made compact in order to conform to the standard, it is necessary to minimize the outer tube. Therefore, if the inner diameter of the outer tube is set to a value close to the outer diameter of the arc tube, there is a problem that it is difficult to achieve both the storing operation of the arc tube in the outer tube and the sealing of the outer tube.

  The present invention includes a high-pressure discharge lamp, a method for manufacturing the same, and a high-pressure discharge lamp that can achieve both a housing operation of an arc tube using translucent ceramics and sealing of the outer tube even when the outer tube is minimized. An object of the present invention is to provide a lighting device.

    A high-pressure discharge lamp according to a first aspect of the present invention includes a translucent ceramic hermetic container, a pair of electrodes sealed in a translucent ceramic hermetic container at a distance from each other, a discharge medium sealed in the translucent ceramic hermetic container, and An arc tube having a current introduction conductor hermetically introduced into a translucent ceramic hermetic container and connected to an electrode; and a current supply conductor having a sliding contact portion that is hermetically introduced inside and acts in the axial direction The arc tube is housed in the state where at least one current introduction conductor is slidably connected in the axial direction to the sliding contact portion of the current supply conductor, and is kept airtight against the outside air and has an airtight space inside. And an outer tube formed.

  The first invention achieves the object of the present invention by improving the configuration of the current supply conductor introduced into the outer tube as described above. That is, a sliding contact connecting portion for connecting the current introducing conductor of the arc tube so as to be slidable in the axial direction is disposed on the current supply conductor.

  The arc tube has a proximal end exposed to the outside, an intermediate portion hermetically penetrating a sealing portion formed in the translucent ceramic hermetic container, and a distal end exposed to the inside of the translucent ceramic hermetic container to serve as an electrode. A current introduction conductor to be connected is provided. In addition, the discharge medium can employ various configurations depending on the type of the high-pressure discharge lamp.

  In addition, the arc tube allows the translucent ceramic hermetic container to have a structure sealed with frit glass, but may have a structure sealed without using frit glass if desired. Therefore, the translucent ceramic hermetic container may be provided with a small-diameter cylindrical portion for forming a slight gap called a capillary, or may be substantially not provided with a small-diameter cylindrical portion. .

  The current supply conductor provided in the outer tube is connected to an external lighting circuit to function as a current supply means, and is airtightly introduced into the outer tube. Therefore, the base end portion of the current supply conductor is exposed to the outside of the outer tube, the intermediate portion is hermetically sealed to the outer tube, and the distal end portion is exposed to the inside of the outer tube.

  The current supply conductor is made of a conductor, but the material and configuration are not particularly limited. Further, the means for introducing the current supply conductor into the outer tube in an airtight manner is not particularly limited.

  A known sealing means can be appropriately employed depending on the translucent member constituting the outer tube, preferably glass and the material of the current supply conductor in the airtight introduction portion. For example, in order to airtightly introduce the current supply conductor with quartz glass as the outer tube, molybdenum sealing is used as a sealing metal foil, and the sealing metal foil is hermetically embedded in the sealing portion, such as shrink sealing or crushing. Sealing or a combination thereof can be used. In this configuration, a refractory metal such as molybdenum, tungsten, or platinum can be used for a portion that is connected to the molybdenum foil and exposed to the outside of the outer tube and a portion that is also exposed to the inside of the outer tube.

  Further, when the pair of current supply conductors is disposed, the sliding contact connecting portions of the current supply conductors are disposed on both or one of them. The function of electrically conducting between the current introducing conductor exposed from the arc tube to the outside, the mechanical holding function that contributes to supporting the arc tube, and the current supply conductor and the current introducing conductor are conducted. It has a sliding function that allows relative sliding while maintaining. In addition to the above function, an auxiliary support function for holding the end portion of the translucent ceramic hermetic container of the arc tube can be added as desired.

  The current supply conductor may be a slidable contact portion having the above function, and the specific structure of the slidable contact portion is not particularly limited in the present invention. For example, a structure in which the tip of the current supply conductor has a coil shape or a sleeve shape can be employed.

  In addition, when the sliding contact connection portions are disposed on both of the pair of current supply conductors, not only the configuration in which both sliding contact connection portions continue their functions, but also one sliding contact connection portion, After the current introduction conductor is connected thereto, the current supply conductor and the current introduction conductor are fixed by welding or caulking, so that the sliding function is lost after the lamp is completed. May be.

  Thus, in the first aspect of the invention, stress is applied between the current supply conductor and the current introduction conductor at the time of manufacturing the lamp and during lighting and extinguishing due to the difference in thermal expansion coefficient between the arc tube and the outer tube. In some cases, the relative sliding between the slidable contact portion of the current supply conductor and the current introduction conductor connected thereto occurs, so that the stress is absorbed. As a result, the occurrence of defects such as cracks in the sealing material of the sealing portion of the translucent ceramic hermetic container is suppressed.

  Further, since the current supply conductor has the sliding contact portion, the surface area of this portion is increased and the heat capacity is also increased, so that the gap between the sealing portion of the current introduction conductor and the sealing portion of the outer tube is increased. Thermal effects can be reduced.

    A high-pressure discharge lamp according to a second aspect of the present invention includes a light-transmitting ceramic hermetic container, a pair of electrodes sealed in a light-transmitting ceramic air-tight container so as to face each other, a discharge medium sealed in the light-transmitting ceramic hermetic container, and An arc tube having a current introduction conductor hermetically introduced into the translucent ceramic hermetic container and connected to the electrode; a tubular outer tube main body having an inner diameter larger than the maximum outer diameter of the translucent ceramic hermetic container, A thin tube portion connected to one end of the tube main portion, a first sealing portion formed at the other end of the outer tube main portion, a second sealing portion formed in the thin tube portion, and a base end of the first and first And an outer tube having a pair of current supply conductors that are hermetically introduced into the interior via the two sealing portions and whose tip is connected to the current introduction conductor to support the arc tube. It is characterized by that.

  The second invention achieves the object of the present invention by improving the sealing structure of the outer tube as described above. That is, a pair of sealing portions disposed at both ends of the outer tube are configured as asymmetric first and second sealing portions. It is preferable that the first invention is included.

  The arc tube is allowed to have the same configuration as in the first invention.

  The outer tube includes an outer tube main body portion, a thin tube portion, first and second sealing portions, and a pair of current supply conductors, and is kept airtight against the outside air.

  The outer tube main body has an inner diameter larger than the outer diameter of the arc tube. In order to make the high-pressure discharge lamp as compact as possible, the inner diameter of the outer tube main body is set to a range of about 1.2 to 3.5 times, preferably 1.5 to 3.0 times the outer diameter of the arc tube. It is good to do. In addition, the outer tube main body portion is assumed to have a length in the tube axis direction at least enough to accommodate the arc tube therein. Further, the outer tube main body can be easily manufactured by making the inner shape cylindrical, but the inner shape is not particularly limited as long as the arc tube can be accommodated.

  The first sealing portion is formed by closing the open end which is the other end of the tubular outer tube main portion, and introduces one of the pair of current supply conductors in an airtight manner. Before the first sealing portion is formed, the arc tube can be inserted into the inside from the open end which is the other end of the tubular outer tube main body. For this reason, if the inner diameter of the outer tube is slightly larger than the outer diameter of the arc tube, the arc tube can be housed inside the outer tube. In addition, the shape of the first sealing portion is preferably formed so that the cross section in the direction orthogonal to the tube axis is substantially circular. Further, if desired, the first sealing portion can be used as a mounting portion when the base is mounted on the high pressure discharge lamp.

  Further, the first sealing portion may employ a structure in which the sealing of one current supply conductor and the closing of the open end of the outer tube main body are separated in time and space if desired. it can.

  That is, as a first aspect thereof, one current supply conductor is introduced in advance in an airtight manner, and the first sealing portion and a glass portion separated from the sealing portion in the axial direction of the current supply conductor, for example, a cup-shaped portion The glass portion of the sealing glass bulb is glass-welded to the open end of the outer tube main body housing the arc tube.

  Further, as the second aspect, a sealing glass bulb mainly composed of the first sealing portion by introducing one current supply conductor in an airtight manner in advance, and an outer tube main body containing the arc tube The glass is welded mainly to the outer peripheral portion of the first sealing portion in the sealing glass bulb.

  Therefore, the first and second aspects of the first sealing portion described above can be obtained by implementing a third invention to be described later.

  The narrow tube portion or the exhaust tube portion is connected to one end of the outer tube main body, is thinner than the outer tube, and communicates with the inside of the outer tube. In order to facilitate the connection of the thin tubes, the one end side of the outer tube main portion can be formed in advance so as to be sequentially reduced in diameter such as a hemisphere. Further, by storing the arc tube in advance and forming the first sealing portion, the inside of the outer tube can be exhausted through the narrow tube. Furthermore, if desired, a desired atmospheric gas can be sealed in the outer tube after exhausting.

  Further, the other current supply conductor is inserted into the thin tube portion and is airtightly introduced into the outer tube via a second sealing portion described later.

  Thus, the second sealing portion described later can be formed after exhausting the inside of the outer tube using the narrow tube portion or after the subsequent sealing. Therefore, the inner diameter and the wall thickness of the thin tube are not particularly limited as long as they are such that exhaust, sealing, and current supply conductors in the outer tube can be sealed.

  As can be understood from the above, the second sealing portion is formed in the narrow tube portion. Therefore, the second sealing portion can be formed smaller than the first sealing portion. By doing so, the amount of heat required for forming the second sealing portion is reduced, and even if the second sealing portion is formed in a state where the arc tube is housed in the outer tube, the arc tube It can prevent that the sealing part located in the 2 sealing part side is damaged by heat receiving.

  The aspects of the first and second sealing portions are not particularly limited in the present invention. A known sealing means can be appropriately employed according to the material of the translucent member constituting the outer tube, preferably the glass and the material of the current supply conductor that is hermetically embedded in the sealing portion. For example, if the outer tube is quartz glass and the current supply conductor is molybdenum, then using a molybdenum foil as a sealing metal foil, shrink sealing or crushing sealing that seals the sealing metal foil in a sealed portion Or a combination thereof can be used.

  The sliding contact connection portion according to the first aspect of the present invention can be formed on at least one of the pair of current supply conductors that are airtightly introduced into the outer tube. According to this aspect, when forming the sealing glass bulb in the third invention to be described later, it is possible to leave the arc tube not connected to one of the current supply conductors. Thereby, it can prevent that the sealing part of an arc_tube | light_emitting_tube is damaged by heat reception by the heating at the time of forming the glass bulb | ball for sealing.

    Next, a preferable aspect of introducing the current supply conductor into the outer tube in the first and second inventions will be described. That is, in the first aspect, the current supply conductor is airtightly introduced into the outer tube through the conductive portion of the sealing body made of the functionally gradient material.

  The seal body is a mixed sintered body of a refractory conductive metal powder and a refractory insulator powder, and is a functionally graded material in which a conductive portion, an intermediate portion, and a nonconductive portion are sequentially adjacent. As the refractory conductive metal powder, for example, a refractory conductive metal powder such as Mo or W can be used.

  The conductive portion is rich in refractory conductive metal, has a relatively high conductivity, and constitutes a part of the current supply conductor.

  The main portion of the external lead member and the current supply conductor is connected to the conductive portion. Although the main part of the external lead member and the current supply conductor can be constituted by a single conductor having a rod shape so as to penetrate the conductive part of the seal body, in order to obtain high airtightness The main part of the external lead member and the current supply conductor are configured separately so that the conductive part is interposed between the main part of the external lead member and the current supply conductor, and are separated from each other in the conductive part. It is good to arrange.

The non-conductive portion is rich in a refractory insulator and has a relatively high insulating property, and its thermal expansion coefficient approximates that of the outer tube. And a nonelectroconductive part seals to the opening part of an outer tube | pipe, and a sealing body and an outer tube | pipe cooperate and form a sealing part. As the refractory insulator powder, for example, a powder such as SiO ₂ can be used.

Moreover, it is preferable that the non-conductive portion is adjusted in advance to have a coefficient of thermal expansion approximate to that of the outer tube. In order to make the non-conductive portion approximate to the coefficient of thermal expansion of the outer tube, it is preferable to use a material similar to the constituent material of the outer tube as a main component. When the outer tube is made of quartz glass or hard glass, good sealing properties can be obtained between the outer tube and the outer tube by using a material mainly composed of SiO ₂ .

  The intermediate portion is interposed between the conductive portion and the nonconductive portion, and the refractory conductive metal powder and the refractory insulator powder are intermediate to the mixing ratio in the conductive portion and the nonconductive portion. They are mixed in proportions, and have an intermediate thermal expansion coefficient with respect to the thermal expansion coefficient of each of the conductive portion and the non-conductive portion. At the same time, a portion having an intermediate conductivity is formed. The intermediate portion functions as a relaxation zone for the difference in thermal expansion coefficient between the conductive portion and the non-conductive portion.

  The intermediate portion has a thermal expansion coefficient of a portion adjacent to the conductive portion of the sealing body close to that of the conductive portion, and a thermal expansion coefficient of the portion adjacent to the nonconductive portion is a nonconductive portion. It is comprised so that the coefficient of thermal expansion may approach. Therefore, as a preferable configuration of the intermediate coefficient of thermal expansion, the coefficient of thermal expansion and the conductivity are distributed with a plurality of values between the conductive part and the non-conductive part. And as a mode of a plurality of values, any of continuous and stepwise may be sufficient.

  In order to manufacture the functionally graded material for the sealing body, various known configurations and manufacturing methods can be appropriately employed.

  Thus, since the portion of the current supply conductor introduced into the outer tube is constituted by the sealing body made of the functionally gradient material, the non-conductive portion that surrounds the conductive portion of the sealing body is sealed when the outer tube is sealed. Since it is heated and sealed to the outer tube, it is not necessary to directly heat the current supply conductor and the conductive portion of the seal body. Furthermore, since an intermediate portion is interposed between the non-conductive portion and the conductive portion that are heated for sealing, the current supply located in the outer tube when sealing the outer tube and the seal body Less heat is transferred to the conductor.

  As a result, in this embodiment, thermal damage that acts on the arc tube due to heat when the outer tube is sealed is effectively suppressed. That is, this embodiment is effective because the conduction heat passing through the current supply conductor is reduced.

  On the other hand, in the conventional high-pressure discharge lamp of this type, when the light-transmitting ceramic hermetic container of the arc tube is sealed with a general frit glass, the heat resistance of the sealed portion of the arc tube is high. Therefore, it is necessary to set the distance between the sealed portion of the arc tube and the sealed portion of the outer tube as large as possible. Therefore, there exists a problem that a high pressure discharge lamp will enlarge.

  Moreover, according to the 1st aspect, the length of sealing part itself can be shortened by sealing an outer tube | pipe using the sealing body which consists of a functionally gradient material. For example, the length of the sealing portion can be reduced to about half compared to sealing using a sealing metal foil.

  To summarize the above, in the first aspect, the distance between the sealing portion of the outer tube and the arc tube and the length of the sealing portion can be shortened. It is effective.

    A preferred second mode for introducing the current supply conductor into the outer tube is a configuration in which the seal body and the outer tube form a shrink seal portion. The seal body can be formed into a desired shape effective for shrink sealing, for example, by forming it into a columnar shape.

  Shrink sealing is performed by heating and softening the opening from the outer peripheral side in a state where the sealing body is inserted into the opening of the outer tube, and sealing the outer tube while evacuating and maintaining a reduced pressure state. Thus, the softened opening is welded while being reduced in diameter to the sealing body to form a sealing portion. In the present invention, a sealing portion formed by shrink sealing is referred to as a shrink sealing portion.

  And according to the 2nd aspect, while being able to obtain favorable sealing, sealing becomes easy.

    According to a third aspect of the present invention, there is provided a high pressure discharge lamp manufacturing method comprising: a translucent ceramic hermetic container; a pair of electrodes sealed in a translucent ceramic hermetic container spaced apart from each other; A first step of manufacturing an arc tube having a current introduction conductor hermetically introduced into a discharge medium and a translucent ceramic hermetic vessel and connected to an electrode; and first current supply conductor hermetically sealed A second step of preparing a sealing glass bulb having one sealing portion and connecting at least one current introduction conductor of the arc tube to one current supply conductor to support the arc tube on the sealing glass bulb. And a glass outer tube having a tubular outer tube main body having an inner diameter larger than the maximum outer diameter of the translucent ceramic hermetic container and having one end opened, and a thin tube connected to the other end of the outer tube main body. Prepare the outer tube The arc tube supported by the sealing glass bulb obtained in the second step from the open end of the body part is inserted into the outer tube main part, and the space between the open end of the outer pipe main part and the sealing glass bulb is hermetically sealed A third step of hermetically sealing the open end of the main part of the outer tube with glass; and connecting the other current introduction conductor of the arc tube to the other current supply conductor, And a fourth step of forming a second sealing portion in which the other current supply conductor is inserted and the current supply conductor is hermetically sealed to the thin tube portion.

  The third invention is a method suitable for manufacturing the high-pressure discharge lamp of the second invention.

  A known arc tube manufacturing process can be adopted for the first process.

  In the second step, the sealing glass bulb includes a first sealing portion in which one current supply conductor is hermetically sealed. That is, one current supply conductor is hermetically sealed to the glass bulb material to form the first sealing portion, and the glass bulb material is inserted into the open end of the outer tube main portion and the above-mentioned glass welding is performed. Seal the open end. For this reason, the glass bulb material is formed in a shape and size that is convenient for sealing the open end by inserting it into the open end of the outer tube main body.

  The glass bulb material is preferably formed in a cup shape so as to easily fit into the open end of the outer tube main body and form a reduced diameter end of the outer tube. However, if the first sealing portion has an appropriate outer diameter, the open end of the outer tube main portion is directly welded to the outer peripheral portion of the first sealing portion, for example, while reducing the diameter. It is also permissible to seal the open end of the outer tube main body with a sealing glass bulb. In this case, the first sealing portion apparently has a large diameter that is relatively close to the outer diameter of the outer tube main portion. In the case of the above aspects, most of the glass bulb material is constituted only by the first sealing portion.

  Moreover, even if the glass material of the glass bulb for sealing is cup-shaped, the open end of the outer tube main body is directly reduced to the outer peripheral portion of the first sealing portion as desired, for example, while reducing the diameter. It is also possible to seal the open end of the outer tube main body with a sealing glass bulb.

  The connection between the one current supply conductor of the sealing glass bulb and the one current introduction conductor of the arc tube is preferably performed after the one current supply conductor is hermetically sealed to the sealing glass bulb. Then, when the first sealing portion is formed, the arc tube, in particular, the sealing portion facing the one current supply conductor does not need to receive a thermal history. In order to realize this, the slidable contact portion in the first invention may be formed on one of the current supply conductors.

  However, if desired, one current supply conductor of the sealing glass bulb and one current introduction conductor of the arc tube can be connected before the one current supply conductor is hermetically sealed to the sealing bulb. In this aspect as well, the sliding contact portion in the first invention can be formed on one of the current supply conductors of the sealing glass bulb. However, a fixed connection is allowed from the beginning if desired.

  Further, in the aspect in which the sliding contact connection portion is formed on one current supply conductor, the connection portion between the sliding contact connection portion and one current introduction conductor of the arc tube may be in a state in which it can be slid as it is. In addition, for example, a fixed connection state can be obtained by welding, caulking, or the like.

  In the third step, it is possible to adopt a mode in which the connection between the other current introduction conductor of the arc tube and the other current supply conductor of the outer tube is performed in advance before the arc tube is inserted into the main portion of the outer tube. it can. In this case, the sealing bulb, the arc tube and the other current supply conductor are integrated to form an arc tube mount. In addition, after the insertion, in the fourth step, as will be described later, the other current supply conductor is inserted from the end face of the thin tube into the thin tube and connected to the other current introduction conductor of the arc tube. Also good. Further, the other current supply conductor is inserted into the narrow tube in advance, and when the arc tube is inserted into the outer tube main body, the other current introduction conductor is connected to the sliding contact portion of the other current supply conductor. There may be.

  In the other current supply conductor, it is preferable to form the slidable contact portion in the first invention in any of the above aspects.

  Further, in the third step, the glass welding between the outer tube main body portion and the sealing glass bulb for sealing the open end of the outer tube main body portion is mainly performed when the outer tube after completion is viewed as described above. Thus, it may be performed within the region of the outer tube main body portion, or may be performed mainly in the region of the first sealing portion, and hence around the first sealing portion. In the case of the latter mode, since the thickness of the first sealing portion is increased, it appears that the diameter of the first sealing portion is increased in appearance.

  In the fourth step, the other current supply conductor is inserted into the narrow tube before forming the second sealing portion. The other current supply conductor is inserted into the thin tube, but the tip thereof may be located inside the thin tube, or may protrude from the thin tube and be located in the outer tube main body.

  Prior to the formation of the second sealing portion, it is preferable to evacuate the outer tube to make the inside vacuum, but an appropriate atmospheric gas can be sealed thereafter if desired. Further, the structure of the second sealing portion is allowed to be the same as that described in the second invention.

  According to the first to fourth inventions, a high-pressure discharge lamp that can achieve both the operation of housing the arc tube in the outer tube and the sealing of the outer tube using the translucent ceramics even when the outer tube is minimized, and its manufacture A method and a lighting device comprising a high-pressure discharge lamp can be provided.

  According to the first invention, in addition to the above, the contraction and expansion in the tube axis direction due to the difference in the thermal expansion coefficient between the arc tube and the outer tube are absorbed between the current introduction conductor and the feeding conductor. A high-pressure discharge lamp and a high pressure for preventing the disconnection between the current introduction conductor and the power supply conductor due to vibration or reducing the stress applied to the sealing portion of the arc tube to hold the arc tube at a predetermined position in the outer tube An illumination device including a discharge lamp can be provided.

  Furthermore, according to the second invention, in addition to the above, the outer diameter and the overall length can be shortened, and a compact high-pressure discharge lamp and a lighting device including the high-pressure discharge lamp can be provided.

  According to the third invention, in addition to the above, it is possible to provide a method for manufacturing a high-pressure discharge lamp that is easy to manufacture and has high reliability.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

    1 and 2 show a first embodiment for carrying out the high-pressure discharge lamp according to the first invention, FIG. 1 is a sectional view of a main part, and FIG. 2 is a sectional view of an arc tube. In this embodiment, the high-pressure discharge lamp HDL includes a luminous tube IT and an outer tube OT.

[About arc tube IT]
As shown in FIG. 2, the arc tube IT includes a translucent ceramic hermetic container 1, an electrode 2, a discharge medium, and a current introduction conductor 3. In the illustrated embodiment, a sealing material 4 is used to seal the translucent ceramic hermetic container 1. In FIG. 1, the arc tube IT has a contour indicated by a dotted line, and a thin ink portion indicates the outer surface.

(About translucent ceramic hermetic container 1)
The translucent ceramic hermetic container 1 is formed mainly of translucent ceramics. Translucent ceramics include translucent alumina, yttrium-aluminum-garnet (YAG), yttrium oxide (YOX), and polycrystalline non-oxides such as polycrystalline or single crystal such as aluminum nitride (AlN). Ceramics or the like can be used. If necessary, it is allowed to form a halogen-resistant or metal-resistant transparent coating on the inner surface of the hermetic container or to modify the inner surface of the hermetic container.

  The translucent ceramic hermetic container 1 has a discharge space 1c therein. And in order to enclose discharge space 1c, translucent airtight container 1 is provided with enclosing part 1a. The surrounding portion 1a has a discharge space 1c formed therein having an appropriate shape, for example, a spherical shape, an elliptical spherical shape, or a substantially cylindrical shape. Various values can be selected as the volume of the discharge space 1c according to the rated lamp power of the high-pressure discharge lamp DHL, the distance between the electrodes, and the like. For example, in the case of a liquid crystal projector lamp, it can be 0.5 cc or less. In the case of a vehicle headlamp, it can be 0.05 cc or less. In the case of a general illumination lamp, it can be set to 1 cc or more and any of the following depending on the rated lamp power.

  Further, the surrounding portion 1a may be configured so that the linear transmittance of the main portion is more than 20%, preferably more than 30%, and more preferably more than 50% if desired. The main part is an important part having a great influence on light distribution with respect to the derivation of the light generated by the discharge, and is mainly a part facing between a pair of electrodes 2 and 2 described later.

  Thus, if the linear transmittance is within the above range, light distribution control becomes easy in combination with an optical system such as a reflecting mirror. Therefore, a high-pressure discharge lamp suitable for an application such as an automobile headlamp is provided. Obtainable. However, if the linear transmittance is 20% or less, the discharge arc appears to be too thick, making it difficult to control the light distribution, and a desired light distribution pattern cannot be obtained. Therefore, when it is required to strictly control the light distribution so as to be incorporated in an automobile headlamp or the like and satisfy a predetermined standard, it becomes difficult. In addition, if the linear transmittance exceeds 30%, the apparent discharge arc becomes thinner and the light distribution control becomes easier, and if it exceeds 50%, the light distribution control becomes even easier. In addition, since the one where the linear transmittance is higher is preferable, there is no upper limit.

  Furthermore, the translucent ceramic hermetic container 1 is allowed to include a small-diameter cylindrical portion 1b continuous to the surrounding portion 1a as desired. The small-diameter cylindrical portion 1b generally extends in the tube axis direction from both ends of the surrounding portion 1a in the tube axis direction, the inside communicates with the surrounding portion 1a, and a pair thereof is disposed.

  The inner diameter of the small diameter cylindrical portion 1b is clearly smaller than the inner diameter of the surrounding portion 1a, for example, 1/10 or less. And in the state which the translucent ceramic airtight container 1 is not sealed, it has the elongate through-hole extended in a pipe-axis direction inside the small diameter cylinder part 1a, The one end of the discharge space 1c of the enclosure part 1a The other end is open to the outside.

  Further, if desired, the linear transmittance of the small diameter cylindrical portion 1b can be made lower than the linear transmittance of the surrounding portion 1a. Since the linear transmittance of the small-diameter cylindrical portion 1b hardly affects the light distribution directly, it may be lower than the linear transmittance of the surrounding portion 1a. If the linear transmittance is relatively low, for example, even when the surface of the surrounding portion 1a, for example, the outer surface is polished to increase the linear transmittance, the surface of the small-diameter cylindrical portion 1b, for example, the outer surface is not polished. The small-diameter cylindrical portion 1b can be formed by using light-transmitting ceramic particles having a large average particle diameter as described above. Therefore, the high-pressure discharge lamp can be easily manufactured and is inexpensive.

  Further, the translucent ceramic hermetic container 1 is preferably formed so that the surrounding portion 1a and the small-diameter cylindrical portion 1b are continuously integrated. This is because, with such a configuration, thermal and optical discontinuous portions are not formed in the translucent ceramic hermetic container 1. According to the most typical structure in this configuration, the surrounding portion 1a and the small diameter cylindrical portion 1b of the translucent ceramic hermetic container 1 are formed by integral molding. Further, according to the different structure, before forming the translucent ceramic hermetic container 1, the whole of the surrounding portion 1a and the small-diameter cylindrical portion 1b or those portions are compression-molded with the ceramic fine particle material as separate members. Or prepared by pre-sintering, and then each member is incorporated into the shape of a light-transmitting ceramic hermetic container 1 in a sintering mold and then sintered, so that adjacent members are separated. The alumina particles are directly bonded to obtain a translucent ceramic hermetic container 1 free from thermal and optical discontinuities. On the other hand, in the translucent ceramic hermetic container 1 having a so-called shrink-fit structure, a thermal and optical discontinuous portion is formed, but can be adopted as desired.

(About electrode 2)
In general, a pair of electrodes 2 is disposed so as to be sealed in a light-transmitting ceramic hermetic container 1 and face the discharge space 1c inside. In general, the distance between the electrodes formed between the pair of electrodes 2 and 2 is preferably 5 mm or less. In the case of a high-pressure discharge lamp for an automobile headlamp, the center value is 4.2 mm. Has been.

  Further, the constituent material of the electrode 2 is fire-resistant and has a conductive metal such as pure tungsten (W), a dopant (for example, scandium (Sc), aluminum (Al), potassium (K) and silicon (Si). 1) or a doped tungsten containing thorium oxide, rhenium (Re) or tungsten-rhenium (W-Re) alloy, or the like. Can do.

  Furthermore, in the case of a small high-pressure discharge lamp, a straight rod-shaped wire or a wire with a large diameter formed at the tip can be used as the electrode. In the case of a medium or large electrode, an electrode coil made of an electrode constituent material can be wound around the tip of the electrode shaft. The pair of electrodes 2 and 2 have the same structure when operating with an alternating current. However, when operating with direct current, since the temperature of the anode is generally large, the heat radiation area is larger than that of the cathode, and thus the main part can be thick.

  Further, the intermediate portion and the base end of the electrode 2 are inserted into the small diameter cylindrical portion 1b of the translucent ceramic hermetic container 1, and a slight gap called a capillary is formed between the inner surface of the small diameter cylindrical portion 1b. Is done. Note that the proximal end of the electrode 2 is connected to and supported by the distal end of an introduction conductor 3 described later.

(Discharge medium)
The discharge medium includes at least a starting gas and an ionization medium that contributes to light emission. Note that the start gas may serve as a medium that contributes to light emission if desired. It preferably also includes an ionization medium for forming a lamp voltage.

  The starting gas also acts as a buffer gas, and can enclose one kind of group such as xenon (Xe), argon (Ar), and neon (Ne) alone, or a mixture of plural kinds. The enclosure pressure of the rare gas can be appropriately set according to the use of the high pressure discharge lamp.

  Among rare gases, xenon has a relatively low thermal conductivity because its atomic weight is larger than other rare gases, so that it is sealed at 0.6 atm or more, preferably at least 5 atm. This contributes to the formation of the lamp voltage and emits white visible light when the vapor pressure of the halide is low, thereby contributing to the rise of the luminous flux, which is effective in the case of a high-pressure discharge lamp for a headlamp. In this case, the preferable sealing pressure of xenon is 6 atmospheres or more, more preferably in the range of 8 to 16 atmospheres. For this reason, it contributes to luminous flux rise and light color rise immediately after lighting, and can satisfy the standard of white light emission as an HID light source for automobile headlamps immediately after lighting.

  The medium that contributes to light emission is mainly composed of a halide of a light emitting metal, and it is allowed to enclose the light emitting metal as it is if desired. In the present invention, the luminescent metal is not particularly limited, but as a preferred example, a thulium (Tm) halide can be mainly encapsulated.

  Thulium halide is a luminescent metal halide suitable as a mercury-free lamp, and mainly emits visible light by discharge. Further, thulium halide can be sealed at a maximum sealing ratio in the ionization medium sealed in the translucent ceramic hermetic container 1, preferably 40 to 90% by mass in addition to this condition. Thulium halide itself has a high vapor pressure, which is an ionization medium for forming a lamp voltage, which will be described later, and is itself a potential between electrodes 2 and 2 in the presence of a metal halide that emits less visible light. It has the effect of increasing the gradient and hence the lamp voltage.

  In addition, thulium halide has a low vapor pressure, but the thulium emission peak coincides with the peak of the visibility curve. Therefore, thulium halide is a luminescent metal that is extremely effective for improving the luminous efficiency. The emission intensity of thulium greatly depends on the operating temperature during lighting of the high-pressure discharge lamp, and the efficiency becomes maximum under the condition that the coldest part temperature is about 800 ° C. When the translucent ceramic hermetic container 1 is formed mainly of translucent ceramic, there is no problem in operation under conditions where the coldest part temperature is about 800 ° C., and the chemical resistance is strong. The inclusion of the halide does not adversely affect the lamp life and the luminous flux maintenance factor. That is, thulium halide is a luminescent metal halide suitable for a high-pressure discharge lamp using an airtight container made of translucent ceramics.

  In addition to the above, other luminescent metal halides allowed to be sealed include the following.

  1. (Alkali Metal) When the alkali metal is encapsulated, it is allowed within a range of less than 10% by mass with respect to all metal halides encapsulated in the translucent ceramic hermetic container 1. When the sealing ratio of the alkali metal is 10% by mass or more, the lamp voltage tends to decrease, which is not preferable from the viewpoint of forming the lamp voltage. However, if the sealing ratio of the alkali metal is less than 10% by mass, a decrease in lamp voltage is suppressed to the minimum, while light emission efficiency, lamp life improvement, and light color adjustment, particularly color deviation improvement are possible. From such a point of view, when a required lamp voltage can be ensured, sealing is permitted within the above range. In addition, Preferably it is 2-8 mass%, More preferably, it is 3-7 mass%, More preferably, it is 4-6 mass%. Further, as the alkali metal, it is possible to selectively enclose mainly sodium (Na), but / or if desired, and / or at least one of cesium (Cs) and lithium (Li).

  Sodium (Na) mainly contributes to the improvement of luminous efficiency. Cesium (Cs) contributes to the improvement of life characteristics by optimizing the discharge arc temperature. Lithium (Li) contributes to the improvement of red color rendering.

  2. (Other Rare Earth Metal Halides) In addition to thulium halides, the following metal halides can be encapsulated mainly as luminescent metal halides. One or a plurality of halides of rare earth metals in the group consisting of praseodymium (Pr), cerium (Ce), holmium (Ho), neodymium (Nd) and samarium (Sm).

  The rare earth metal is useful as a luminescent metal next to thulium halide, and is allowed to be encapsulated at an encapsulation ratio of a predetermined amount or less. That is, any of the rare earth metals has an infinite number of bright line spectra in the vicinity of the peak wavelength of the visibility characteristic curve, and thus can contribute to an improvement in luminous efficiency.

  In addition, when the rare earth metal halide is added, it is preferable that the encapsulation ratio with respect to the total ionization medium including the thulium (Tm) halide is 50 mass% or more.

  3. (Thallium or / and indium halide) The thallium (Tl) and / or indium (In) halide is selectively encapsulated as a secondary component for the purpose of obtaining a desired color rendering property and / or color temperature. It is acceptable. Indium is also effective as an ionization medium for forming a lamp voltage.

  The thallium (Tl) halide can add a green component of thallium having an emission line at a wavelength of 535 nm during light emission. In addition, it is desirable that the enclosure ratio range of thallium halide that can be generally adopted is less than 30% by mass with respect to all the metal halides to be enclosed. When the enclosure ratio range of thallium halide is 30% by mass or more, the decrease in luminous efficiency becomes significant. In addition, it is preferable to enclose within a range of less than 15% by mass.

  Further, by adding indium (In) halide, the blue component can be increased during light emission of the halide, and also contributes to the formation of a lamp voltage.

  As the halogen of each luminescent metal halide described above, iodine is suitable because it has moderate reactivity. However, if desired, either bromine or chlorine may be used, and iodine, bromine and chlorine may be used. Two or more desired ones may be used.

  Next, as a lamp voltage forming ionization medium, when a mercury-free high-pressure discharge lamp is obtained, it is preferable to enclose a metal halide having a high vapor pressure and low visible light emission as described above. In this case, it is preferable not to contain mercury (Hg) at all for the purpose of reducing environmentally hazardous substances, but it is acceptable even if it is contained to the extent of impurities. Further, when obtaining a high-pressure discharge lamp containing mercury, mercury is enclosed.

  In the case of mercury-free, for example, the following metals are effective to be sealed as an ionization medium for forming a lamp voltage. That is, zinc (Zn), aluminum (Al), magnesium (Mg), iron (Fe), cobalt (Co), chromium (Cr), nickel (Ni), manganese (Mn), aluminum (Al), antimony (Sb) ), Beryllium (Be), rhenium (Re), gallium (Ga), titanium (Ti), zirconium (Zr), and hafnium (Hf). Since each metal halide has a high vapor pressure, a large cross-sectional area of collision with electrons, and a large ionization potential, a lamp voltage in place of mercury is used in combination with the light-transmitting ceramic hermetic container 1 described above. It is a suitable material as an ionizing medium for formation.

(About the current introduction conductor 3)
The current introduction conductor 3 is a member having a function for supplying power to the electrode 2, a function for sealing the translucent ceramic hermetic container 1, and a function for supporting the electrode 2. The base end portion is exposed to the outside from, for example, the small-diameter cylindrical portion 1 b of the translucent ceramic hermetic container 1 and connected to a lighting circuit (not shown), and the tip end portion is connected to the base end of the electrode 2. When the translucent ceramic hermetic container 1 includes the small diameter cylindrical portion 1b as shown in FIG. 2, the tip of the current introduction conductor 3 is inserted into the inside of the small diameter cylindrical portion 1b. Connected to the base end.

  Further, the diameter of the portion of the current introduction conductor 3 inserted into the small diameter cylindrical portion 1b can be made larger than at least the base end portion of the electrode 2, preferably the diameter of the electrode shaft. Thereby, the diameter of the electrode 2 or the electrode shaft 2a can be set to an optimum size without being influenced by the diameter of the introduction conductor 3, and erosion due to the retention of the ionized medium is reduced.

  Further, the entire current introducing conductor 3 may be formed of a sealing conductive member, or may be formed of a series connection structure of a sealing conductive member and a halogen-resistant conductive member. When the entire introduced conductor 3 is formed of a sealing conductive member, it is a matter of course that the sealing conductive member takes into account the above three functions. On the other hand, when the current introduction conductor 3 is formed of a serially connected structure of a sealing conductive member and a halogen-resistant conductive member, the sealing conductive member cooperates with the small-diameter cylindrical portion and a sealing material 4 described later. It is in charge of the function of sealing the translucent ceramic hermetic container 1 and the halogen-resistant conductive member is in charge of supporting the electrode, and both members are in charge of supplying power to the electrode.

  As the sealing conductive member, a conductive member having a thermal expansion coefficient close to that of the electrode is preferably used. For example, niobium (Nb), tantalum (Ta), platinum (Pt), or the like can be used depending on the type of translucent ceramic. In addition, niobium is suitable when the translucent airtight container 1 is made of translucent polycrystalline alumina ceramics.

  As the halogen-resistant conductive member, a member having fire resistance that can withstand heat transfer from the electrode and a thermal expansion coefficient close to that of the electrode constituent material is preferably used. For example, it can be selected from tungsten (W), molybdenum (Mo), cermet and the like. The cermet is formed by firing a mixture of ceramic particles and refractory conductive metal (for example, Mo or W) powder.

  In order to connect the electrode 2 to the current introduction conductor 3 in advance and support the electrode 2 to facilitate the assembly to the translucent ceramic hermetic container 1, for example, the electrodes can be integrated by butt welding to constitute an electrode mount. it can. Further, when the current introduction conductor 3 is formed of a sealing conductive member and a halogen-resistant conductive member, these can be integrated by butt welding.

(About sealing material 4)
The sealing material 4 is made of high melting point frit glass or the like, and enters between the inner surface of the small-diameter cylindrical portion 1b of the translucent ceramic hermetic container 1 and the introduction conductor 3 to hermetically seal the translucent ceramic hermetic container 1. To do. In order to perform this sealing, pellets of the sealing material 4 are applied around the introduction conductor 3 at the end of the small-diameter cylindrical portion 1b and melted by heating, as is adopted as a general method. Can do. If it does so, since the sealing material 4 fuse | melted at high temperature will approach into the slight clearance gap formed between the inner surface of the small diameter cylinder part 1b, and the introductory conductor 3, it will solidify. In addition, since the sealing material 4 covers the site | part which functions for sealing of the introductory conductor 3, even if it is a substance inferior to halogen resistance like niobium, it is satisfactory.

[Outer tube OT]
As shown in FIG. 1, the outer tube OT includes an outer tube main body 6 and a current supply conductor 7. In the illustrated form, the outer tube OT includes a sealing portion 8 in addition to the above. Although not shown in FIG. 1 because it is cut out in FIG. 1, the outer tube OT includes a sealing portion and one current supply conductor at the other end. In FIG. 1, the thin ink portion of the outer tube OT shows a cross section.

(About the outer pipe main part 6)
The outer tube main body 6 is made of, for example, quartz glass. As shown in FIG. 1, the outer tube main body 6 houses the arc tube IT therein, and the inside is held airtight with respect to the outside. Although the shape of the outer tube main body 6 is not particularly limited, for example, it has a substantially cylindrical shape that is long in the tube axis direction.

(About current supply conductor 7)
The current supply conductor 7 is airtightly introduced into the outer tube OT. That is, the base 7a of the current supply conductor 7 is exposed to the outside of the outer tube OT, and the intermediate 7b is introduced into the outer tube OT airtightly through a sealing portion 8 described later, and further to the distal end side. It has a sliding contact portion 7c.

  In the case of this embodiment, the intermediate 7b includes the sealing metal foil 7b1, and the sealing metal foil 7b1 is embedded in the inside of the sealing portion 8 so that the above-described airtight introduction is achieved. Realize. When a pair of current supply conductors 7 is provided, at least one of the current supply conductors 7 has the above configuration, but the other current supply conductor 7 may have a different configuration. .

  In the case of this embodiment, the slidable contact portion 7c is realized by forming the tip side portion of the current supply conductor 7 in a coil shape. The inner diameter of the coil is slightly smaller than or substantially equal to the diameter of the current introduction conductor 3, and the current introduction conductor 4 can be inserted into the sliding contact connection portion 7c. And both are comprised so that sliding of a pipe-axis direction is possible relatively.

(About the sealing part 8)
The sealing portion 8 is formed by, for example, shrink sealing, and the above-described current supply conductor 7 is airtightly introduced through the sealing portion 8.

(Supporting the arc tube IT in the outer tube OT)
The arc tube IT is housed in the outer tube OT, and both ends thereof are supported by a pair of current supply conductors 7 and 7. FIG. 1 shows only the state of support on one end side.

[Operation of high-pressure discharge lamp]
In the first form of the first invention, the arc tube IT is supported at a predetermined position in the outer tube OT by holding both ends thereof between the pair of current supply conductors 7.

  The arc tube IT includes the translucent ceramic hermetic container 1, while the outer tube OT is formed of a material having a different thermal expansion coefficient from that of the translucent ceramic such as glass. Therefore, the high-pressure discharge lamp HDL is used. In the repetition of turning on and off, the expansion and contraction in the tube axis direction based on the difference in thermal expansion coefficient between the arc tube IT and the outer tube OT is repeated.

  In this embodiment, since at least one of the current supply conductors 7 has the slidable contact portion 7c, the tube extends along the tube axis direction between the current supply conductor 7 and the current introduction conductor 3 during expansion and contraction. When the stress is applied, the current supply conductor 3 slides relatively in the sliding contact connecting portion 7c while maintaining conduction, so that the stress is absorbed. Therefore, it is possible to effectively suppress the occurrence of inconvenience such as a crack in the sealing material 4 at the sealing portion of the arc tube IT.

  Further, since the exhaust tip-off portion is not formed at the intermediate portion of the tube unlike the conventional outer tube, it is optically advantageous.

  Example 1 relates to the high-pressure discharge lamp shown in FIG.

Current introduction conductor: Diameter 0.65mm
Sliding contact portion of current supply conductor: Mo wire with a diameter of 0.5 mm was wound into a coil shape with an inner diameter of 0.7 mm for 5 turns.

FIG. 3 is a cross-sectional view of a principal part showing a second embodiment for carrying out the high-pressure discharge lamp of the first invention. This embodiment is different from the first embodiment in that the slidable contact connecting portion 7c of the current supply conductor 7 has a sleeve shape.

  Sliding contact portion of current supply conductor: A Mo sleeve having an outer diameter of 1.2 mm and an inner diameter of 0.75 mm was used.

Others are the same as the first embodiment.

FIG. 4 is a cross-sectional view showing an embodiment for carrying out the high-pressure discharge lamp of the second invention. In the figure, the same parts as those in FIG. In this embodiment, the high-pressure discharge lamp HDL is substantially the same as that in the first invention in that the arc tube IT and the outer tube OT are provided, but the configuration of the outer tube OT is as described below. Is different.

  That is, the outer tube OT includes, in addition to the outer tube main body portion 6, a narrow tube portion 9, a first sealing portion 8A and a second sealing portion 8B, and a pair of current supply conductors 7A and 7B. For example, it is made of quartz glass.

  The outer tube main body portion 6 is a main portion of the outer tube OT, and is a translucent hollow body portion having an inner diameter larger than the outer diameter of the arc tube IT in order to accommodate the arc tube IT therein. For example, it has a substantially cylindrical shape. Further, at least one end of the outer tube main body 6, for example, the left end in the drawing, that is, one end is formed in a hemispherical shape, a cap shape, or a reduced diameter shape. In the drawing, the right end can have various shapes according to the size and / or shape of the first sealing portion 8A.

  The thin tube portion 9 is connected to one end of the outer tube main body 6 and communicates with the inside of the outer tube main body 6. And while being utilized as exhaust_gas | exhaustion inside the outer pipe | tube main-body part 6 and an enclosure path | route, the 2nd sealing part 6B is formed and sealed so that it may mention later.

  The first sealing portion 8 </ b> A is formed at the other end portion of the outer tube main body portion 6. In this embodiment, the first sealing portion 8A is formed by using, for example, a sealing glass bulb 10. The sealing glass bulb 10 has one current supply conductor 7A introduced in an airtight manner at the base end thereof, and expands in a deep shade shape from the base end. In a portion where the current supply conductor 7A is introduced in an airtight manner, a sealing metal foil 7b1 which is a portion of the current supply conductor 7A is embedded in an airtight manner by shrink sealing, for example.

  Further, the portion of the sealing glass bulb 10 that is expanded in a deep shade shape can be configured by sealing the other end of the outer tube main body portion 6 by glass welding and constituting a part thereof. In the figure, the sealing glass bulb 10 clearly shows the boundary between the outer tube main body 6 and the sealing glass bulb 10 and the outer tube main body 6 are welded to each other. The above boundaries are practically indistinguishable.

  As described above, the second sealing portion 8B is formed in the portion that seals the thin tube portion 9, and the sealing metal foil 7b1 that is the portion of the sealing metal foil 7b1 of the current supply conductor 7B is hermetically embedded. ing.

  Each of the pair of current supply conductors 7A and 7B has a base end 7a exposed to the outside of the outer tube OT, an intermediate 7b provided with the sealing metal foil 7b1, and a sliding contact portion 7c on the tip end side. Then, the base end portions of the pair of current introduction conductors 3A, 3B of the arc tube IT are inserted into the sliding contact portion 7c, and at the same time, the arc tube IT is supported at a predetermined position in the outer tube OT. Yes. In addition, although the sliding contact part 7c has comprised the coil shape, it cannot be overemphasized that the sleeve shape may be comprised, for example.

  Also, one current introduction conductor 3A of the arc tube IT is inserted into the sliding contact connection portion 7c of one current supply conductor 7A. The other current introduction conductor 3B of the arc tube IT is inserted into the sliding contact connection portion 7c of the other current supply conductor 7B. As a result, the arc tube IT can be connected to the lighting circuit via the pair of current supply conductors 7A and 7B while being supported at a predetermined position in the outer tube OT.

Glass bulb for sealing: Molded body of quartz glass tube with outer diameter of 6.8 mm, inner diameter of 3.0 mm Outer tube main part: Molded body of quartz glass tube with outer diameter of 11.0 mm, inner diameter of 9.0 mm First and second sealing parts: Sealed metal foil is 7.0mm wide and 20μm thick Mo foil Pair of current supply conductors: 0.5mm diameter Mo wire Light emitting tube: Outer diameter of translucent ceramic hermetic container 4.5mm, total length 38mm

5 and 6 show an embodiment for carrying out the method for manufacturing a high-pressure discharge lamp of the third invention, FIG. 5 is an explanatory diagram of the first and second steps, and FIG. 6 is the third and fourth steps. It is explanatory drawing of this process. In the figure, the same parts as those in FIG.

  First, the first and second steps in this embodiment will be described with reference to FIG.

  In the first step, the arc tube IT is manufactured.

  In the second step, the sealing bulb 10 is prepared, and the arc tube IT is supported by the sealing bulb 10. This support can be performed by inserting one current supply conductor 7A into the sliding contact connection portion 7c of one current introduction conductor 3A of the arc tube IT. Further, if desired, the other current supply conductor 7B before sealing can be connected to the arc tube IT by inserting the sliding contact connecting portion 7c into the other current introduction conductor 3B of the arc tube IT.

  Next, the third and fourth steps in this embodiment will be described with reference to FIG.

  In the third step, in addition to the outer tube main body 6 having a required portion (the Fukasa portion in this embodiment) of the sealing bulb 10 supporting the arc tube IT in the second step connected to the narrow tube 9 'at one end. Inserting the inside of the outer tube main body 6 from the open end formed at the end to store the arc tube IT in the outer tube main body 6, and heating the open end and the required part to make both It integrates by welding and seals the open end of the outer tube main body 6.

  The fourth step is a step of sealing the thin tube 9 ′ to form the second sealing portion 8B. Prior to the formation of the second sealing portion 8B, the other current supply conductor 7B is inserted into the narrow tube 9 'in advance. Then, since the inside of the outer tube main body 6 is evacuated to be in a vacuum state, for example, the sealing metal foil 7b1 of the thin tube 9 'and the region facing the front and back thereof are heated and softened, and the second is formed by shrink sealing, for example. The sealing portion 8B is formed.

    FIG. 7 is a partially cutaway sectional view showing a third embodiment for carrying out the first invention and a second embodiment for carrying out the second invention, as well as an enlarged perspective view of an essential part and an enlarged plan view of an essential part. It is. In the figure, the same parts as those in FIG.

  In this embodiment, the outer tube OT is configured to introduce the current supply conductor into the inside thereof using the sealing body S made of the functionally gradient material, and to form the sealing portion 8 of the outer tube OT.

That is, the sealing body S has a cylindrical shape, the central portion has a conductive portion Rc, the outer peripheral portion has a nonconductive portion Ri, the intermediate portion has an intermediate portion Rm, and a mixed sintered body of Mo powder and SiO ₂ powder. It consists of functionally gradient material formed by the above.

  The conductive portion Rc is a Mo-rich layer and has high conductivity, and is located at the center of the seal body S. And it functions as a part in the intermediate part of the current supply conductor 7, and the lamp current flows mainly.

The non-conductive portion Ri is an SiO ₂ rich layer and has an insulating property or low conductivity, and the outer peripheral portion of the seal body S is formed so as to surround the conductive portion Rc. And it has a thermal expansion coefficient that approximates the thermal expansion coefficient of the opening of the outer tube OT, and functions as a portion that seals the outer tube OT by sealing it to the opening end of the unsealed outer tube OT. .

The intermediate portion Rm has a coefficient of thermal expansion intermediate to that of the conductive portion Rc and the nonconductive portion Ri, in which Mo and SiO ₂ are mixed at an appropriate ratio. It functions as a relaxation zone between the conductive portion Rc and the nonconductive portion Ri.

  The intermediate portion Rm preferably further has an inclined structure in order to enhance the function as a relaxation zone. In the inclined structure, the conductivity on the side adjacent to the conductive portion Rc is relatively higher than that of the conductive portion, and the side adjacent to the nonconductive portion Ri is relatively conductive than that of the nonconductive portion Ri. The conductivity is gradually changed at an intermediate portion thereof. The gradient change in conductivity may be stepwise or continuous.

  Therefore, in the sealing body S, the boundary between the conductive portion Rc, the intermediate portion Rm, and the non-conductive portion Ri changes in a stepwise or continuous and sequentially inclined change in conductivity or thermal conductivity. In many cases, the boundary between each part is unclear.

  Further, the intermediate portion 7b and the base end 7a of the current supply conductor 7 are connected to the conductive portion Rc of the seal body S in a state of being separated from each other with the conductive portion Rc interposed therebetween. The connection of the intermediate 7b and the base end 7a to the conductive portion Rc can be selectively performed as desired either before or after the sealing body S is sintered.

  The sealing body S is inserted into the opening of the unsealed outer tube OT, and then the opening and the non-conductive portion Ri of the sealing body S are heated and melted to be fused together, thereby sealing the outer tube OT. 8 is formed. In the illustrated form, the sealing portion 8 is formed by shrink-sealing the opening of the outer tube OT to the outer peripheral surface of the seal body S.

    FIG. 8 is a conceptual diagram showing an automobile headlamp as an embodiment of an illumination device provided with the high-pressure discharge lamp of the present invention. In the figure, 11 is a headlamp body, 12 is a high pressure discharge lamp lighting device, and 13 is a high pressure discharge lamp.

  The headlamp body 11 has a container shape, and includes a reflecting mirror 11a inside, a lens 11b on the front surface, and a lamp socket not shown.

  The high pressure discharge lamp lighting device 12 includes a main lighting circuit 12A and a starter 12B.

  The high-pressure discharge lamp 13 is mounted on the lamp socket and lights up.

Sectional drawing which shows the 1st form for implementing the high pressure discharge lamp of 1st invention Similarly, cross-sectional view of arc tube Sectional drawing which shows the 2nd form for implementing the high pressure discharge lamp of 1st invention Sectional drawing which shows one form for implementing the high pressure discharge lamp of 2nd invention Explanatory drawing which shows the 1st and 2nd process in one form for implementing the manufacturing method of the high pressure discharge lamp of 3rd invention. Explanatory drawing which similarly shows the 3rd and 4th process Partially cutaway sectional view, main part enlarged perspective view and main part enlarged plan view showing a third embodiment for carrying out the first invention and a second embodiment for carrying out the second invention The conceptual diagram which shows the motor vehicle headlamp as one form of the illuminating device which arrange | positioned the high-pressure discharge lamp of this invention

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Translucent ceramic hermetic container, 2 ... Electrode, 3A ... One electric current introduction conductor, 3B ... The other electric current introduction conductor, 4 ... Sealing material, 6 ... Outer tube main part, 7A ... One electric current supply conductor, 7B ... the other current supply conductor, 7c ... sliding contact connection part, 8A ... first sealing part, 8B ... second sealing part, 9 ... thin tube part, 10 ... sealing bulb, HDL ... high pressure discharge lamp, IT ... arc tube, OT ... outer tube

Claims (6)

A light-transmitting ceramic hermetic container, a pair of electrodes sealed in a light-transmitting ceramic hermetic container, facing each other, a discharge medium sealed in the light-transmitting ceramic hermetic container, and a gas-tightness in the light-transmitting ceramic hermetic container An arc tube with a current introduction conductor introduced and connected to the electrode;
A current supply conductor having a sliding contact portion that is airtightly introduced into the inside and acts in the axial direction, and at least one current introduction conductor is slidably connected in the axial direction to the sliding contact portion of the current supply conductor And an outer tube that is hermetically sealed against the outside air and forms an airtight space therein.
A high-pressure discharge lamp comprising: A light-transmitting ceramic hermetic container, a pair of electrodes sealed in a light-transmitting ceramic hermetic container, facing each other, a discharge medium sealed in the light-transmitting ceramic hermetic container, and a gas-tightness in the light-transmitting ceramic hermetic container An arc tube with a current introduction conductor introduced and connected to the electrode;
A tubular outer tube main portion having an inner diameter larger than the maximum outer diameter of the translucent ceramic hermetic container, a thin tube portion connected to one end of the outer tube main portion, and a first seal formed at the other end of the outer tube main portion Part, the second sealing part formed in the narrow tube part, and the base end are hermetically introduced into the inside via the first and second sealing parts, respectively, and the tip is connected to the current introduction conductor to emit light An outer tube with a pair of current supply conductors supporting the tube;
A high-pressure discharge lamp comprising:   The current supply conductor has a sealing body made of a functionally graded material having a conductive portion, an intermediate portion, and a non-conductive portion, and sealing the outer tube at the non-conductive portion. The high-pressure discharge lamp according to claim 1 or 2, wherein the high-pressure discharge lamp is hermetically introduced into the outer tube through a sexual part.   4. The high pressure discharge lamp according to claim 3, wherein the seal body forms a shrink seal portion in the outer tube in cooperation with the outer tube. A light-transmitting ceramic hermetic container, a pair of electrodes sealed in a light-transmitting ceramic hermetic container, facing each other, a discharge medium sealed in the light-transmitting ceramic hermetic container, and a gas-tightness in the light-transmitting ceramic hermetic container A first step of fabricating an arc tube with a current introduction conductor introduced and connected to the electrode;
A sealing glass bulb having a first sealing portion in which one current supply conductor is hermetically sealed is prepared, and at least one current introduction conductor of the arc tube is connected to one current supply conductor to emit light. A second step of supporting the tube on a sealing glass bulb;
Prepare a glass outer tube having a tubular outer tube main body having an inner diameter larger than the maximum outer diameter of the translucent ceramic hermetic container and having one end opened and a thin tube connected to the other end of the outer tube main body. The arc tube supported by the sealing glass bulb obtained in the second step from the open end of the outer tube main portion is inserted into the outer tube main portion, and the open end of the outer tube main portion and the sealing glass bulb are inserted. A third step of sealingly sealing the open end of the main portion of the outer tube by glass-sealing between the two;
With the other current introduction conductor of the arc tube connected to the other current supply conductor, the other current supply conductor was inserted into the thin tube of the outer tube, and the current supply conductor was hermetically sealed to the thin tube portion. A fourth step of forming a second sealing portion;
A method for producing a high-pressure discharge lamp, comprising: A lighting device body;
The high-pressure discharge lamp according to claim 1 or 2, which is disposed in the lighting device body;
A lighting device for lighting the high-pressure discharge lamp;
An illumination device comprising:

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