JP4606019B2 - High pressure discharge lamp manufacturing method, high pressure discharge lamp and lamp unit - Google Patents

Description

  The present invention relates to a method for manufacturing a high-pressure discharge lamp, a high-pressure discharge lamp, and a lamp unit. In particular, the present invention relates to a method for manufacturing a high-pressure discharge lamp used for general illumination or a combination of a reflector and a projector, an automobile headlamp, and the like.

  In recent years, image projection apparatuses such as liquid crystal projectors and DMD projectors are widely used as systems for realizing large screen images, and high-pressure discharge lamps exhibiting high brightness are generally widely used for such image projection apparatuses. ing. A configuration of a conventional high-pressure discharge lamp 1000 is schematically shown in FIG. A lamp 1000 shown in FIG. 12 is a so-called ultra-high pressure mercury lamp, and is disclosed in Patent Document 1, for example.

  The lamp 1000 includes an arc tube (bulb) 101 made of quartz glass and a pair of sealing portions (seal portions) 102 extending from both ends of the arc tube 101. Inside the arc tube 101 (discharge space), a luminescent substance (mercury) 106 is sealed, and a pair of tungsten electrodes (W electrodes) 103 made of tungsten are opposed to each other at a certain interval. Are arranged. One end of the W electrode 103 is welded to a molybdenum foil (Mo foil) 104 in the sealing portion 102, and the W electrode 103 and the Mo foil 104 are electrically connected. An external lead (Mo bar) 105 made of molybdenum is electrically connected to one end of the Mo foil 104. In addition to the mercury 106, the arc tube 101 is also filled with argon (Ar) and a small amount of halogen.

  The operation principle of the lamp 1000 will be briefly described. When a starting voltage is applied between the W electrodes 103 and 103 via the external lead 105 and the Mo foil 104, discharge of argon (Ar) occurs, and this discharge causes the arc tube. The temperature in the discharge space 101 increases, and the mercury 106 is heated and vaporized. Thereafter, mercury atoms are excited at the center of the arc between the W electrodes 103 and 103 to emit light. The higher the mercury vapor pressure of the lamp 1000 is, the more the emitted light is. Therefore, the higher the mercury vapor pressure, the more suitable as the light source of the image projection apparatus, but from the viewpoint of the physical pressure strength of the arc tube 110, 15-20 MPa (150 The lamp 1000 is used at a mercury vapor pressure in the range of ~ 200 atmospheres).

In addition, there exists patent document 2 mentioned later as a related literature.
JP-A-2-148561 JP 2001-23570 A

  The conventional lamp 1000 has a pressure strength of about 20 MPa. However, research and development for further increasing the pressure strength have been conducted in order to further improve the lamp characteristics (see, for example, Patent Document 2). This is because today, in order to realize a higher-performance image projection apparatus, a lamp with higher output and higher power is required, and in order to satisfy this requirement, a lamp with higher pressure resistance is required. Because.

  More specifically, in the case of a high-power / high-power lamp, in order to prevent the electrode from evaporating faster as the current increases, more mercury is enclosed than usual to increase the lamp voltage. There is a need. If the amount of enclosed mercury is not sufficient for the lamp power, the lamp voltage cannot be increased to the required level, which increases the lamp current, and as a result, the electrodes evaporate quickly, resulting in a practical lamp. Can not. In other words, from the viewpoint of realizing a high output lamp, it is sufficient to increase the lamp power and to produce a short arc type lamp in which the distance between the electrodes is shorter than the conventional one. In producing a high-power / high-power lamp, it is necessary to improve the pressure strength and increase the amount of enclosed mercury. And in today's technology, a high-pressure discharge lamp that can be put to practical use with an extremely high pressure strength (for example, about 30 MPa or more) has not yet been realized.

  The inventors of the present application have succeeded in developing a high-pressure discharge lamp exhibiting extremely high pressure strength (for example, about 30 MPa or more), and disclosed it in Japanese Patent Application No. 2002-351524. However, it has been found that even such an excellent high-pressure discharge lamp can be further improved by improving the manufacturing method.

  The present invention has been made in view of such various points, and a main object of the present invention is to provide a method capable of more effectively manufacturing a high-pressure discharge lamp having high pressure strength.

The method for producing a high-pressure discharge lamp according to the present invention is a method for producing a high-pressure discharge lamp having an arc tube in which a luminescent material is sealed in a tube and a sealing portion for maintaining the hermeticity of the arc tube. Preparing a glass pipe for a discharge lamp having an arc tube portion to be an arc tube and a side tube portion extending from the arc tube portion, and introducing mercury bromide (HgBr ₂ ) into the arc tube portion And a step of forming the sealing portion from the side tube portion, and the step of forming the sealing portion includes a second softening point lower than that of the first glass constituting the side tube portion. A glass member composed of the glass of No. 2 is inserted into the side tube portion, and then the step of heating the side tube portion to closely contact the glass member and the side tube portion, The glass part at a temperature higher than the strain point temperature of the second glass. And it includes a heating step of heating the at least containing part of the side tube portion.

  The heating step is preferably performed at a temperature lower than the strain point temperature of the first glass.

In a preferred embodiment, the glass member is a glass tube or glass plate made of SiO ₂ and at least one of 15% by weight or less of Al ₂ O ₃ and 4% by weight or less of B.

Another method for producing a high-pressure discharge lamp of the present invention is a method for producing a high-pressure discharge lamp having an arc tube in which a luminescent material is sealed in a tube and a pair of sealing portions extending from both ends of the arc tube. A step of preparing a discharge lamp glass pipe having an arc tube portion serving as an arc tube of a high-pressure discharge lamp and a pair of side tube portions extending from both ends of the arc tube portion; A glass tube made of a second glass having a softening point lower than that of the first glass constituting the side tube portion, and an electrode structure including at least an electrode rod, Next, a step of forming one sealing portion of the pair of sealing portions by heat shrinking the side tube portion; and after forming the one sealing portion, in the arc tube portion, introducing a luminous substance and mercury bromide (HgBr _2); After the light emitting material is introduced, a glass tube made of the second glass and an electrode structure including at least an electrode rod are inserted into the other side tube portion of the one side, and then the side tube portion A step of forming an arc tube in which the other sealing portion with respect to the one and the luminescent material are encapsulated by heating and shrinking; for a lamp complete body in which both the sealing portion and the arc tube are formed, A heating step of heating a portion including at least the glass tube and the side tube at a temperature higher than the strain point temperature of the second glass and lower than the strain point temperature of the first glass; Including.

  The heating step is preferably performed for 2 hours or more.

  In a preferred embodiment, the heating step is performed for 100 hours or more.

In a preferred embodiment, when the sealing portion is measured using a sensitive color plate method using a photoelastic effect, the region constituted by the second glass is 10 kgf / cm ² or more and 50 kgf / cm ^2. The heating step is performed so that the following compressive stress in the longitudinal direction of the side tube portion exists.

  In a preferred embodiment, the compressive stress is generated for each of the pair of sealing portions.

  In a preferred embodiment, the heating is performed by placing the finished lamp body in a furnace having a temperature higher than the strain point temperature of the second glass and lower than the strain point temperature of the first glass. Executed.

  In a preferred embodiment, the inside of the furnace is in a vacuum or a reduced pressure state.

In a preferred embodiment, the first glass contains 99% by weight or more of SiO _2, and the second glass contains at least one of 15% by weight or less of Al ₂ O ₃ and 4% by weight or less of B. One and SiO ₂ are included.

  In a preferred embodiment, the heating temperature is 1030 ° C. ± 40 ° C.

In one embodiment, the high-pressure discharge lamp is a high-pressure mercury lamp, and mercury as the luminescent material is sealed in an amount of 150 mg / cm ³ or more based on the inner volume of the arc tube.

The high-pressure discharge lamp of the present invention includes an arc tube in which a luminescent material is enclosed in a tube, and a sealing portion that maintains the hermeticity of the arc tube, and the sealing portion extends from the arc tube. 1 glass part, and the 2nd glass part provided in at least one part inside the said 1st glass part, and the said sealing part is the site | part to which the compressive stress is applied Mercury bromide (HgBr ₂ ) is enclosed in the arc tube.

Another high-pressure discharge lamp of the present invention includes an arc tube in which a luminescent material is sealed in a tube, and a pair of sealing portions that maintain the hermeticity of the arc tube, and each of the pair of sealing portions includes: The first glass part extending from the arc tube and the second glass part provided at least in part inside the first glass part, and the pair of sealing parts Each of which has a portion to which a compressive stress is applied, and the compressive stress is measured when the sealing portion is measured using a sensitive color plate method utilizing a photoelastic effect, the second glass. 10 kgf / cm ² or more and 50 kgf / cm ² or less in a region corresponding to the portion, and a pair of electrode rods are arranged to face each other in the arc tube, and each electrode rod of the pair of electrode rods Is connected to the metal foil, the metal foil is the sealing part And at least a connection portion between the metal foil and the electrode rod is located in the second glass portion, and mercury bromide (HgBr ₂ ) is used as a halogen precursor in the arc tube. Is enclosed.

  The lamp unit of the present invention includes the high-pressure discharge lamp and a reflecting mirror that reflects light emitted from the high-pressure discharge lamp.

  In one embodiment, the electrode structure includes the electrode rod, a metal foil connected to the electrode rod, and an external lead connected to the metal foil.

  It is preferable that a metal film made of at least one metal selected from the group consisting of Pt, Ir, Rh, Ru, and Re is formed on at least a part of the electrode rod.

  In one embodiment, a coil having at least a surface of at least one metal selected from the group consisting of Pt, Ir, Rh, Ru, and Re is wound around at least a part of the electrode rod.

  In one embodiment, a small-diameter portion in which an inner diameter of the side tube portion is smaller than other portions is provided around the boundary between the side tube portion and the arc tube portion in the discharge lamp glass pipe. .

  A high-pressure discharge lamp according to an embodiment includes an arc tube in which a luminescent material is sealed in a tube, and a sealing portion that maintains airtightness of the arc tube, and the sealing portion extends from the arc tube. It has a first glass part and a second glass part provided on at least a part of the inside of the first glass part, and performs strain measurement by a sensitive color plate method using a photoelastic effect. Then, compressive stress is observed in at least a part of a region corresponding to the second glass portion in the sealing portion.

  The strain measurement may be performed using a SVP-200 strain tester manufactured by Toshiba.

In the present invention, since mercury bromide (HgBr ₂ ) is introduced into the arc tube portion, composition deformation of the second glass can be suppressed. Therefore, compressive strain can be effectively applied to the second glass portion, or cracks can be prevented from occurring between the second glass portion and the first glass portion. As a result, a high-pressure discharge lamp having a high pressure strength can be manufactured more effectively.

  The present invention can be applied not only to a high-pressure mercury lamp but also to other high-pressure discharge lamps such as a metal halide lamp and a xenon lamp, and can also be applied to a mercury-free metal halide lamp containing no mercury. Since the mercury-free metal halide lamp according to the present invention has a high pressure resistance, it is possible to enclose a rare gas at a high pressure. As a result, the efficiency can be easily improved, and in addition, the startability of lighting can be improved. Note that the present invention can be applied not only to a high-pressure mercury lamp but also to a light bulb (for example, a halogen light bulb), thereby preventing bursting compared to the conventional one.

According to the present invention, since mercury bromide (HgBr ₂ ) is sealed in the arc tube, the compositional deformation of the second glass can be suppressed, and as a result, a high-pressure discharge lamp having high pressure strength can be more reliably obtained. Can be manufactured and provided.

  First, before explaining the embodiment of the present invention, a high pressure mercury lamp exhibiting a very high pressure resistance with a lighting operating pressure of about 30 to 40 MPa or more (about 300 to 400 atmospheres or more) will be explained. Details of these high-pressure mercury lamps are disclosed in Japanese Patent Application No. 2001-371365. Japanese Patent Application No. 2002-351524 discloses a mechanism in which distortion occurs in the sealing portion of the high-pressure discharge lamp disclosed in Japanese Patent Application No. 2001-371365. Here, these patent applications are incorporated herein by reference.

  Although the development of a high-pressure mercury lamp that can withstand practical use despite the operating pressure of about 30 MPa or more has been extremely difficult, for example, the configuration shown in FIG. The lamp was completed successfully. FIG. 1B is a cross-sectional view taken along the line bb in FIG.

  A high-pressure discharge lamp (for example, a high-pressure mercury lamp or an ultrahigh-pressure mercury lamp) 100 shown in FIG. 1 is disclosed in Japanese Patent Application No. 2001-371365, and maintains the arc tube 1 and the air-tightness of the arc tube 1. A pair of sealing portions 2 are provided, and at least one of the sealing portions 2 is provided on the first glass portion 8 extending from the arc tube 1 and at least a part of the inside of the first glass portion 8. It has the 2nd glass part 7, and the said one sealing part 2 has the site | part (20) to which the compressive stress is applied.

The compressive stress applied to a part of the sealing portion 2 only needs to exceed substantially zero (that is, 0 kgf / cm ² ). Due to the presence of this compressive stress, the pressure strength can be improved as compared with the conventional structure. This compressive stress is preferably about 10 kgf / cm ² or more (about 9.8 × 10 ⁵ N / m ² or more), and about 50 kgf / cm ² or less (about 4.9 × 10 ⁶ N / m 2). ² or less). This is because if it is less than 10 kgf / cm ² , the compressive strain is weak and the pressure strength of the lamp cannot be sufficiently increased. And, in order to achieve a configuration exceeding 50 kgf / cm ² , there is no practical glass material for realizing it. However, even if it is less than 10 kgf / cm ² , if the value exceeds substantially 0, the breakdown voltage can be increased as compared with the conventional structure, and a configuration that can exceed 50 kgf / cm ² can be realized. If a new material is developed, the second glass part 7 may have a compressive stress exceeding 50 kgf / cm ² .

First glass portion 8 in the sealing section 2 is for containing SiO ₂ 99 wt% or more, for example, and a quartz glass. On the other hand, the second glass part 7 contains at least one of 15 wt% or less of Al ₂ O ₃ and 4 wt% or less of B and SiO _2, and is made of, for example, Vycor glass. Yes. When Al ₂ O ₃ or B is added to SiO ₂ , the softening point of the glass is lowered. Therefore, the softening point of the second glass part 7 is lower than the softening point temperature of the first glass part 8. Thus, in order to lower the softening point of the second glass part 7, the total amount of Al ₂ O ₃ and B contained in the second glass part 7 is preferably greater than 1% by weight. Vycor glass (trade name) is a glass in which additives are mixed into quartz glass to lower the softening point and improve workability compared to quartz glass. For example, borosilicate glass is heated -It can be produced by chemical treatment to bring it closer to the characteristics of quartz. The composition of Vycor glass is, for example, 96.5% by weight of silica (SiO ₂ ), 0.5% by weight of alumina (Al ₂ O ₃ ), and 3% by weight of boron (B). In the present embodiment, the second glass portion 7 is formed from a glass tube made of Vycor glass. Instead of the glass tube made of Vycor, SiO _2: 62 wt%, Al ₂ O _3: 13.8 wt%, CuO: may 23.7% by weight using a glass tube whose components.

  The electrode rod 3 whose one end is located in the discharge space is connected to the metal foil 4 provided in the sealing portion 2 by welding, and at least a part of the metal foil 4 is in the second glass portion 7. positioned. In the configuration shown in FIG. 1, the second glass portion 7 covers a portion including the connection portion between the electrode rod 3 and the metal foil 4. As shown in FIG. 1B, the entire periphery of the metal foil 4 is covered with the second glass portion 7 in the cross section of the sealing portion 2 (the cross section orthogonal to the longitudinal direction of the sealing portion 2). . Thus, at least a part of the metal foil 4 is entirely covered with the second glass portion 7 in the width direction, and the edge portion of the metal foil 4 is surrounded by the second glass portion 7 in this portion. ing. When the dimension of the 2nd glass part 7 in the structure shown in FIG. 1 is illustrated, it is about 2-20 mm (for example, 3 mm, 5 mm, 7 mm) in the length of the longitudinal direction of the sealing part 2, and the 1st The thickness of the 2nd glass part 7 pinched | interposed between the glass part 8 and the metal foil 4 is about 0.01-2 mm (for example, 0.1 mm). The distance H from the end surface of the second glass portion 7 on the arc tube 1 side to the discharge space 10 of the arc tube 1 is about 0 mm to about 6 mm (for example, 0 mm to about 3 mm, or 1 mm to 6 mm). When it is not desired to expose the second glass portion 7 in the discharge space 10, the distance H is greater than 0 mm, for example, 1 mm or more. The distance B from the end face of the metal foil 4 on the arc tube 1 side to the discharge space 10 of the arc tube 1 (in other words, the length embedded in the sealing portion 2 only by the electrode rod 3) is, for example, About 3 mm.

  Next, the compressive strain in the sealing part 2 will be described. 2 (a) and 2 (b) schematically show the distribution of compressive strain along the longitudinal direction (electrode axis direction) of the sealing portion 2, and FIG. 2 (a) shows the second glass portion. On the other hand, in the case of the configuration of the lamp 100 provided with 7, FIG. 2B shows the case of the configuration of the lamp 100 ′ without the second glass portion 7 (comparative example).

  In the sealing portion 2 shown in FIG. 2A, there is a compressive stress (compression strain) in a region (shaded region) corresponding to the second glass portion 7, and the location of the first glass portion 8 ( The magnitude of the compressive stress in the hatched area is substantially zero. On the other hand, as shown in FIG. 2B, in the case of the sealing part 2 without the second glass part 7, there is no portion where local compressive strain exists, and the compressive stress of the first glass part 8. Is substantially zero.

  The inventor of the present application actually measured the distortion of the lamp 100 quantitatively, and observed that compressive stress was present in the second glass portion 7 of the sealing portion 2. This strain was quantified using a sensitive color plate method utilizing a photoelastic effect. The measuring instrument used for the quantification of the strain is a strain tester (Toshiba: SVP-200). When this strain tester is used, the magnitude of the compressive strain of the sealing part 2 is determined by the sealing part. 2 can be obtained as an average value of the stress applied to 2.

  The principle of strain measurement by the sensitive color plate method using the photoelastic effect will be briefly described with reference to FIG. FIGS. 13A and 13B schematically show a state where linearly polarized light transmitted through the polarizing plate is incident on the glass. Here, if the vibration direction of the linearly polarized light is u, u can be regarded as a combination of u1 and u2.

As shown in FIG. 13A, when the glass is not distorted, u1 and u2 pass through the glass at the same speed, so that there is no deviation between u1 and u2 of the transmitted light. On the other hand, as shown in FIG. 13 (b), when the glass is distorted and the stress F is applied, u1 and u2 do not pass through it at the same speed. Deviation occurs between the two. That is, one of u1 and u2 is delayed from the other. This delayed distance is called the optical path difference. Since the optical path difference R is proportional to the stress F and the glass passage distance L, if the proportionality constant is C,
R = C ・ F ・ L
Can be expressed as Here, the unit of each symbol is R (nm), F (kgf / cm ² ), L (cm), and C ({nm / cm} / {kgf / cm ² }), respectively. C is made of a material such as glass and is called a photoelastic constant. As can be seen from the above equation, if C is known, F can be obtained by measuring L and R.

  The inventor of the present application measures the light transmission distance L in the sealing portion 2, that is, the outer diameter L of the sealing portion 2, and uses the distortion standard to determine the optical path from the color of the sealing portion 2 at the time of measurement. The difference R was read. As the photoelastic constant C, the photoelastic constant 3.5 of quartz glass was used. These were substituted into the above formula, and the compressive strain in the longitudinal direction of the metal foil 4 was quantified from the result of the calculated stress value.

  In this measurement, the stress in the longitudinal direction of the sealing portion 2 (the direction in which the electrode shaft 3 extends) was observed, but this does not mean that there is no compressive stress in the other direction. Absent. It is measured whether there is a compressive stress in the radial direction of the sealing portion 2 (the direction from the central axis toward the outer periphery or the opposite direction) or in the circumferential direction of the sealing portion 2 (for example, clockwise direction). In this case, it is necessary to cut the arc tube 1 and the sealing portion 2, but as soon as such cutting is performed, the compressive stress of the second glass portion 7 is relaxed. Therefore, since what can be measured without cutting the lamp 100 is the compressive stress in the longitudinal direction of the sealing portion 2, the inventor of the present application at least quantified the compressive stress in that direction. It is.

  In the lamp 100 of the present embodiment, the second glass portion 7 provided at least in part inside the first glass portion 8 has a compressive strain (at least a compressive strain in the longitudinal direction). The pressure strength of the discharge lamp can be improved. In other words, the lamp 100 of the present embodiment shown in FIGS. 1 and 2A can have higher withstand pressure strength than the lamp 100 'of the comparative example shown in FIG. 2B. The lamp 100 of the present embodiment shown in FIG. 1 can be operated at an operating pressure of 30 MPa or more, which exceeds about 20 MPa, which is the highest operating pressure of the conventional level.

  Next, the reason why the pressure strength of the lamp 100 is increased due to the compressive strain in the second glass portion 7 will be described with reference to FIG. FIG. 14A is an enlarged view of the main part of the sealing part 2 of the lamp 100, while FIG. 14B is an enlarged view of the main part of the sealing part 2 of the lamp 100 'of the comparative example.

  Although there is a part that is not clearly understood about the mechanism of increasing the pressure strength of the lamp 100, the present inventor inferred as follows.

  First, as a premise, since the metal foil 4 in the sealing part 2 is heated and expanded during the lamp operation, stress from the metal foil 4 is applied to the glass part of the sealing part 2. More specifically, in addition to a metal having a higher coefficient of thermal expansion than glass, the metal foil 4 that is thermally connected to the electrode rod 3 and through which an electric current passes is sealed. Since it is more easily heated than the glass part of the stop part 2, stress is easily applied from the metal foil 4 (particularly, from the side of the foil having a small area) to the glass part.

  Here, as shown to Fig.14 (a), when the compressive stress is added to the longitudinal direction of the 2nd glass part 7, it is thought that generation | occurrence | production of the stress 16 from the metal foil 4 can be suppressed. In other words, it is considered that the generation of the large stress 16 by the compressive stress 15 of the second glass portion 7 can be suppressed. As a result, for example, cracks are generated in the glass portion of the sealing portion 2 or the occurrence of leakage between the glass portion of the sealing portion 2 and the metal foil 4 is reduced, and the strength of the sealing portion 2 is improved. Will do.

  On the other hand, as shown in FIG. 14B, in the case of the structure without the second glass portion 7, the stress 17 from the metal foil 4 is larger than in the case of the configuration shown in FIG. I think. That is, since there is no region where compressive stress is applied around the metal foil 4, the stress 17 from the metal foil 4 seems to be larger than the stress 16 shown in FIG. Therefore, it is inferred that the configuration shown in FIG. 14A can improve the withstand pressure strength than the configuration shown in FIG. This idea seems to be compatible with the general property of glass that it is easy to break if the glass has tensile strain (tensile stress) and that it is difficult to break if it has compressive strain (compressive stress).

  However, it cannot be inferred that the sealing part 2 of the lamp 100 has a high pressure resistance because of the general property of the glass that it is difficult to break if the glass has compressive stress. Because, even if the strength of the glass in the region where the compressive strain is increased, the load is generated as compared with the case where there is no strain when viewed as the sealing portion 2 as a whole. This is because the idea that the strength of the sealing portion 2 as a whole is lowered can also hold. The result that the pressure strength of the lamp 100 has been improved is the first time that the inventor of the present application has made a prototype of the lamp 100 and experimented with it, and could not be derived from theory alone. If a larger compressive stress than necessary is left in the second glass portion 7 (or its peripheral peripheral region), the sealing portion 2 is actually damaged when the lamp is turned on, and the life of the lamp is reduced. It may be shortened. Considering such a situation, it is considered that the structure of the lamp 100 having the second glass portion 7 exhibits its high pressure strength under an exquisite balance. If the portion of the arc tube 1 is cut, the stress strain of the second glass portion 7 is relieved, so that the load due to the stress strain of the second glass portion 7 is well received by the entire arc tube 1. It may be.

  In addition, it is thought that the structure which shows the high pressure strength is brought about by the site | part 20 to which the compressive stress produced by the difference of the compressive stress of the 1st glass part 8 and the 2nd glass part 7 is applied. It is done. In other words, the second glass portion 7 (or the periphery of the outer periphery thereof) located on the center side of the portion 20 to which the compressive stress is applied is not applied to the first glass portion 8 substantially. The reason that the compression strain is successfully confined in the only area is that the inference that it has succeeded in exhibiting excellent pressure resistance characteristics can be established. As a result of the stress values being discretely indicated due to the principle of strain measurement by the sensitive color plate method, the portion 20 to which compressive stress is applied is clearly shown in FIG. However, even if the actual stress value can be shown continuously, it is considered that the stress value is changing steeply in the portion 20 to which the compressive stress is applied. It is considered that the portion 20 to which a compressive stress is applied can be defined.

When manufacturing the lamp 100, first, after forming a sealing portion from one side tube portion of the glass pipe for discharge lamp, as shown in FIG. 3A, the arc tube portion 1 ′ to be the arc tube 1 is formed. An issuance substance (mercury) 6 is introduced inside, and at this time, as shown by an arrow 60 in the figure, CH ₂ Br ₂ , which is a halogen precursor substance that decomposes to become halogen, is introduced. Next, the electrode structure 50 including the electrode rod 3 is inserted into the other side tube portion 2 ′. FIG. 3B shows a cross section taken along the line bb in FIG. Finally, when the side tube portion 2 ′ is sealed, a lamp provided with the sealing portion 2 having the second glass portion 7 is obtained.

In order to extend the life of a high-pressure discharge lamp, it is necessary to use a halogen cycle. Therefore, in order to realize a long-life lamp, a halogen precursor (CH ₂ Br ₂ ) that decomposes to generate halogen is introduced. The process becomes important. Alternatively, HBr may be introduced instead of CH ₂ Br ₂ . The amount of halogen necessary for maintaining a good halogen cycle is described in International Application No. PCT / JP00 / 04561 (International Application Date; July 6, 2000, Applicant; Matsushita Electric Industrial Co., Ltd.). It has been detailed. Here, the international application number PCT / JP00 / 04561 is incorporated herein by reference. Although bromine itself (Br ₂ ) can be used as a halogen species, bromine is a highly reactive substance, and in consideration of handling, bromine precursors that decompose to generate halogen (for example, CH ₂ Br ₂ , HBr), it is preferable to introduce the halogen.

In the state shown in FIG. 3, if there is no glass tube 70 to be the second glass portion 7, there is no particular problem in introducing CH ₂ Br ₂ or HBr. The inventor of the present application introduced a halogen precursor (for example, CH ₂ Br ₂ ) as a halogen species in the same manner as when the glass tube 70 is not inserted, but notices that the following problems occur. It was.

The glass tube 70 is made of glass (for example, Vycor glass) having a melting point lower than that of the quartz glass constituting the side tube portion 2 ′, and as described above, the glass is mixed with an additive in the quartz glass. It has a different form. Halogen precursors (CH ₂ Br ₂ and HBr) do not substantially react with quartz glass (side tube portion 2 ′), but affect the glass (Vycor glass) constituting the glass tube 70, The composition is changed. In particular, after the state shown in FIG. 3A in which the introduction of the halogen precursor has been completed, when the periphery of the side tube portion 2 ′ is heated with a burner or the like in order to form a sealing portion, Since the gas composed of the halogen precursor that is attached or exists in the arc tube portion 1 ′ acts as a corrosive gas for the glass tube 70, the glass tube 70 is exposed to a high temperature corrosive gas. End up. If it does so, the composition of the glass tube 70 will change, for example, when the Na component of the glass tube 70 lose | disappears. As a result, along with the change in composition, the thermal properties of the glass change, for example, the strain point becomes high. If the strain point of the glass constituting the glass tube 70 becomes high and approaches the strain point of the quartz glass too much, strain (compression strain) becomes difficult to enter or cannot enter the second glass portion 7. Alternatively, there is a possibility that a crack may enter between the first glass portion 8 and the second glass portion 7.

  Further, when impurities in the glass constituting the glass tube 70 are affected by the halogen or the halogen precursor and the impurities enter (exude) into the arc tube 1, the halogen cycle is caused by the impurities. It can also be disturbed. If the halogen cycle is not operated well, it is difficult to realize a long-life lamp.

The present inventors, in order to prevent the deterioration of the glass pipe 70, was examined the use of mercuric bromide (HgBr ₂₎ as the halogen precursor, the use of the mercuric bromide (HgBr _2), the glass tube 70 It turned out that alteration can be suppressed, and came to this invention. Mercury bromide (HgBr ₂ ), unlike CH ₂ Br ₂ and HBr, which are gases, is a solid, so that the influence on the glass tube 70 can be reduced.

  Embodiments according to the present invention will be described below with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity. In addition, this invention is not limited to the following embodiment.

(Embodiment 1)
In the high-pressure discharge lamp according to the embodiment of the present invention, mercury bromide (HgBr ₂ ) is sealed in the arc tube, and in this respect, halogen precursors (eg, CH ₂ Br ₂ , HBr) or halogens (eg, Br) ) Is not particularly limited as long as it is enclosed, or in some cases, it is different from the high-pressure discharge lamp shown in FIG. Since the other points are basically the same as the configuration shown in FIG. 1, the high-pressure discharge lamp according to Embodiment 1 of the present invention will be described with reference to FIG. For ease of explanation, the reference numeral of the high-pressure discharge lamp of the present embodiment is also “100”, and the points that overlap the configuration shown in FIG. 1 are omitted or simplified.

  The lamp 100 according to this embodiment is a double-ended lamp having two sealing portions 2. As shown in FIG. 1, the arc tube 1 is chipless. Therefore, it is necessary to introduce the luminescent substance and the halogen from the side tube portion instead of providing the arc tube 1 with an opening. Moreover, since the 2nd glass part 7 can arrange | position so that the welding part of the electrode rod 3 and the metal foil 4 may be covered at least, it can reduce a failure | damage probability also on ultrahigh pressure conditions, such as 35 MPa, for example. preferable. As a configuration example for covering the welded portion between the electrode rod 3 and the metal foil 4, a configuration in which the entire metal foil 4 in the portion embedded in the sealing portion 2 and a part of the electrode rod 3 are covered is arranged. There is also.

Mercury bromide (HgBr ₂ ) is sealed in the arc tube 1 as a halogen precursor that decomposes to generate halogen. Halogen generated by decomposition from HgBr ₂ (ie, Br) plays a role of a halogen cycle for returning W (tungsten) evaporated from the electrode rod 3 to the electrode rod 3 again during the lamp operation. The amount of HgBr ₂ enclosed is, for example, about 0.002 to 0.2 mg / cc, and this corresponds to, for example, about 0.01 to 1 μmol / cc when converted to the halogen atom density during lamp operation.

The first advantage when HgBr ₂ is used as the halogen precursor is that the second glass part 7 can be prevented from being deteriorated and the second glass part 7 can be appropriately compressed and strained. . As a result, a high-pressure discharge lamp can be realized more reliably.

A _second advantage of using HgBr ₂ is that what is generated after HgBr ₂ is decomposed is Br and Hg. That is, the same mercury as the element in which components other than halogen are already enclosed. This is different from CH ₂ Br ₂ and HBr in which hydrogen (H) can be generated. Since hydrogen may be combined with halogen again, the amount of free halogen may not be determined depending on the amount of free hydrogen. As disclosed in the above-mentioned International Application No. PCT / JP00 / 04561, the arc tube 1 is secured by always ensuring the halogen contributing to the halogen cycle in the arc tube 1, and the arc cycle is reliably executed. 1 can be positively prevented. However, assuming that hydrogen generated by decomposition (free hydrogen) is generated, it can be said that the halogen associated with the free hydrogen is not necessarily a halogen that contributes to the halogen cycle, and thus can reliably contribute to the halogen cycle. There is a possibility that blackening cannot be positively prevented because the amount of free halogen is not fixed.
Then, it can be seen that HgBr ₂ which can eliminate such a possibility is easier to calculate the amount of introduced halogen and has a larger advantage. In addition, since HgBr ₂ is a solid, there is a possibility that impurities are attached to HgBr _{2. In} such a case, the introduction amount should be defined in consideration of the impurities, or a device for eliminating the impurities should be added. You can do it.

In the present embodiment, the number of moles of halogen generated from HgBr ₂ enclosed in the arc tube 1 is a metal element having a property of binding to halogen (excluding tungsten element and mercury element), and the arc tube It is preferable that the total number of moles of metal elements present in 1 be greater than the sum of the number of moles of tungsten present in the arc tube 1 by evaporation from the electrode 3 during lamp operation. By doing so, it is possible to always ensure the halogen contributing to the halogen cycle in the arc tube 1 and to execute the halogen cycle reliably. A typical example of a metal element having a property of binding to a halogen is an alkali metal element (Na, K, Li, etc.) excluding tungsten element and mercury element.

The pressure strength (operating pressure) of the lamp 100 of this embodiment can be 20 MPa or more (for example, about 30 to 50 MPa or more). Moreover, the tube wall load is, for example, about 60 W / cm ² or more, and no upper limit is set. When exemplarily shown, the tube wall load is, for example, from above about ^{60W / cm 2, 300W / cm} 2 in the range of about (preferably, 80~200W / cm about ²⁾ can be achieved lamp. If a cooling means is provided, it is possible to achieve a tube wall load of about 300 W / cm ² or more. The rated power is, for example, 150 W (in this case, the tube wall load corresponds to about 130 W / cm ² ).

  The configuration of the present embodiment will be described in further detail as follows.

The arc tube 1 of the lamp 100 has a substantially spherical shape, and is made of quartz glass in the same manner as the first glass portion 8. In order to realize a high-pressure mercury lamp (particularly an ultra-high pressure mercury lamp) that exhibits excellent characteristics such as long life, quartz glass constituting the arc tube 1 has a low alkali metal impurity level (for example, Na, It is preferable to use high-purity quartz glass in which the respective amounts of K and Li are 1 ppm or less. Of course, it is also possible to use quartz glass having a normal alkali metal impurity level. The outer diameter of the arc tube 1 is, for example, about 5 mm to 20 mm, and the glass thickness of the arc tube 1 is, for example, about 1 mm to 5 mm. The volume of the discharge space (10) in the arc tube 1 is, for example, about 0.01 to 1 cc (0.01 to 1 cm ³ ). In the present embodiment, the arc tube 1 having an outer diameter of about 9 mm, an inner diameter of about 4 mm, and a discharge space capacity of about 0.06 cc is used.

  A pair of electrode bars (electrodes) 3 are disposed in the arc tube 1 so as to face each other. The tips of the electrode rods 3 are arranged in the arc tube 1 at intervals (arc length) of about 0.2 to 5 mm (for example, 0.6 to 1.0 mm), and each of the electrode rods 3 is made of tungsten. (W). It is preferable to use a tungsten electrode rod 3 having a low alkali metal impurity level (for example, the amount of each of Na, K, and Li is 1 ppm or less). It is also possible to use it. A coil 12 is wound around the tip of the electrode rod 3 for the purpose of lowering the electrode tip temperature during lamp operation. In this embodiment, a coil made of tungsten is used as the coil 12, but a coil made of thorium-tungsten may be used. The electrode bar 3 may be a bar made of thorium-tungsten as well as a tungsten bar.

In the arc tube 1, mercury 6 is enclosed as a luminescent substance. When operating the lamp 100 as an ultrahigh pressure mercury lamp, for example, about 200 mg / cc or more (220 mg / cc or more, 230 mg / cc or more, or 250 mg / cc or more), based on the inner volume of the arc tube 1, Preferably, about 6 mg / cc or more (for example, 300 mg / cc to 500 mg / cc) of mercury 6, noble gas (for example, argon) of 5 to 30 kPa, and HgBr ₂ as a halogen precursor are arc tube 1. It is enclosed inside.

  As described above, the cross-sectional shape of the sealing portion 2 is substantially circular, and the metal foil 4 is provided at the substantially central portion thereof. The metal foil 4 is, for example, a rectangular molybdenum foil (Mo foil), and the width (the length on the short side) of the metal foil 4 is, for example, about 1.0 mm to 2.5 mm (preferably 1.0 mm). About 1.5 mm). The thickness of the metal foil 4 is, for example, about 15 μm to 30 μm (preferably about 15 μm to 20 μm). The ratio of thickness to width is about 1: 100. Moreover, the length (length on the long side) of the metal foil 4 is, for example, about 5 mm to 50 mm.

  An external lead 5 is provided by welding on the side opposite to the side where the electrode rod 3 is located. An external lead 5 is connected to the side of the metal foil 4 opposite to the side to which the electrode rod 3 is connected, and one end of the external lead 5 extends to the outside of the sealing portion 2. By electrically connecting the external lead 5 to a lighting circuit (not shown), the lighting circuit and the pair of electrode rods 3 are electrically connected. The sealing part 2 plays a role of maintaining the hermeticity of the discharge space 10 in the arc tube 1 by crimping the glass parts (7, 8) of the sealing part and the metal foil 4. The sealing mechanism by the sealing part 2 will be briefly described below.

  Since the material constituting the glass part of the sealing part 2 and the molybdenum constituting the metal foil 4 have different coefficients of thermal expansion, they are not integrated from the viewpoint of the coefficient of thermal expansion. . However, in the case of this configuration (foil sealing), the metal foil 4 can be plastically deformed by the pressure from the glass portion of the sealing portion, and the gap generated between the two can be filled. Thereby, the glass part of the sealing part 2 and the metal foil 4 can be brought into a pressure-bonded state, and the inside of the arc tube 1 can be sealed by the sealing part 2. That is, the sealing part 2 is sealed by foil sealing by pressure bonding between the glass part of the sealing part 2 and the metal foil 4. In the present embodiment, since the second glass portion 7 having compressive strain is provided, the reliability of the seal structure is improved.

In the lamp 100 of the present embodiment, the second glass portion 7 provided at least in part inside the first glass portion 8 has a compressive strain (at least a compressive strain in the longitudinal direction). The pressure strength of the discharge lamp can be improved. Since the HgBr ₂ as the halogen precursor is introduced into the arc tube 1, by suppressing the plastic deformation of the second glass portion 7, it is possible to secure an improvement of the pressure resistance.

  In the configuration shown in FIG. 1, the second glass portion 7 is provided in any of the pair of sealing portions 2, but the present invention is not limited thereto, and the second glass portion is provided only in one sealing portion 2. Even if the portion 7 is provided, the pressure resistance can be improved as compared with the lamp 100 ′ of the comparative example shown in FIG. However, it is preferable to have a configuration in which the second glass portion 7 is provided in both the sealing portions 2 and a configuration in which both the sealing portions 2 have portions to which compressive stress is applied. This is because it is possible to achieve higher pressure resistance when both sealing portions 2 have a portion to which compressive stress is applied than one sealing portion, and simply consider The probability that leakage occurs in the sealing portion (that is, a certain level of high withstand voltage) when two sealing portions are provided rather than when one sealing portion having a portion to which compressive stress is applied is provided. This is because it is possible to halve the probability of not being held.

In the present embodiment, a high-pressure mercury lamp with a large amount of mercury 6 enclosed (for example, an ultra-high pressure mercury lamp with a mercury enclosed amount of 150 mg / cm ³ or more) has been described. However, the mercury vapor pressure is not so high. It can be suitably applied to a mercury lamp. This is because the fact that the lamp can be stably operated even when the operating pressure is extremely high means that the reliability of the lamp is high. That is, when the configuration of the present embodiment is applied to a lamp having a low operating pressure (the operating pressure of the lamp is less than about 30 MPa, for example, about 20 MPa to 1 MPa), the reliability of the lamp operating at the operating pressure is improved. This is because it can be improved. In the configuration of the present embodiment, it is only necessary to introduce the member of the second glass portion 7 as a new member into the sealing portion 2, so that the effect of improving the pressure resistance can be obtained with a small improvement. Therefore, it is very suitable for industrial applications. In addition, as a technique for preventing the compositional deformation of the second glass portion 7, HgBr ₂ was used as a halogen precursor in consideration of the mechanism of the compositional deformation. It is suitable for industrial use.

  Next, a method for manufacturing the lamp 100 according to the present embodiment will be described with reference to FIGS.

  First, a glass tube 80 for a discharge lamp having an arc tube portion 1 'serving as an arc tube (1) of the lamp 100 and a side tube portion 2' extending from the arc tube portion 1 'is prepared. The glass pipe 80 of this embodiment is formed by heating and expanding a predetermined position of a cylindrical quartz glass having an outer diameter of 6 mm and an inner diameter of 2 mm to form a substantially spherical arc tube portion 1 ′. Separately, a glass tube 70 to be the second glass portion 7 is prepared. The glass tube 70 of this embodiment is a Vycor glass tube having an outer diameter of 1.9 mm, an inner diameter of 1.7 mm, and a length (length in the longitudinal direction) of 7 mm. The outer diameter of the glass tube 70 is smaller than the inner diameter of the side tube portion 2 ′ so that it can be inserted into the side tube portion 2 ′ of the glass pipe 80.

  Next, as shown in FIG. 4, after fixing the glass tube 70 to the side tube portion 2 ′ of the glass pipe 80, the separately produced electrode structure 50 is attached to the side tube portion 2 ′ to which the glass tube 70 is fixed. Then, both ends of the glass pipe 80 after the electrode structure 50 is inserted are attached to a rotatable chuck 82 while maintaining airtightness. The chuck 82 is connected to a vacuum system (not shown), and the inside of the glass pipe 80 can be depressurized. After evacuating the inside of the glass pipe 80, a rare gas (Ar) of about 200 torr (about 20 kPa) is introduced. Thereafter, the glass pipe 80 is rotated in the direction of the arrow 81 with the electrode rod 3 as the rotation center axis.

  The electrode structure 50 includes an electrode rod 3, a metal foil 4 connected to the electrode rod 3, and an external lead 5 connected to the metal foil 4. The electrode rod 3 is a tungsten electrode rod, and a tungsten coil 12 is wound around the tip thereof. A support member (metal clasp) 11 for fixing the electrode structure 50 to the inner surface of the side tube portion 2 ′ is provided at one end of the external lead 5. The support member 11 shown in FIG. 4 is a molybdenum tape (Mo tape) made of molybdenum, but instead of this, a ring-shaped spring made of molybdenum may be used.

  Next, the side tube portion 2 ′ and the glass tube 70 are heated and shrunk to seal the electrode structure 50, whereby the first glass portion that was the side tube portion 2 ′ as shown in FIG. The sealing part 2 in which the 2nd glass part 7 which was the glass tube 70 was provided inside 8 is formed. The sealing portion 2 is formed by sequentially connecting the side tube portion 2 ′ and the glass tube 70 from the boundary portion between the arc tube portion 1 ′ and the side tube portion 2 ′ to the vicinity of the middle of the external lead 5. This is done by heating and shrinking. By this sealing portion forming step, the sealing portion 2 including a portion where a compressive stress is applied at least in the longitudinal direction (the axial direction of the electrode rod 3) is obtained from the side tube portion 2 'and the glass tube 70. Note that heating / shrinking may be performed from the external lead 5 toward the arc tube portion 1 ′.

Thereafter, a predetermined amount of mercury 6 (for example, about 200 mg / cc, about 300 mg / cc, or more) is introduced from the open end of the side tube portion 2 ′. At this time, solid HgBr ₂ is also introduced. The order of introduction of mercury 6 and HgBr ₂ is not particularly limited. Both may be simultaneous, or one of them may be introduced first.

After the introduction of mercury 6 and HgBr ₂ , the same process as described above is performed for the other side tube portion 2 ′. As shown in FIG. 3, after the electrode structure 50 is inserted into the side tube portion 2 ′ that has not been sealed, the inside of the glass pipe 80 is evacuated (preferably, the pressure is reduced to about 10 ⁻⁴ Pa ), A rare gas is sealed, and then heat-sealed. In this case, it is preferable to perform the heat sealing while cooling the arc tube portion 1 ′ in order to prevent mercury from evaporating. In this way, when both the side tube portions 2 ′ are sealed, a lamp having the second glass portion 7 in the sealing portion 2 is completed. It is also possible to introduce the electrode structure 50 after introducing the mercury 6 first, and then introduce HgBr ₂ .

  Next, a mechanism for applying a compressive stress to the second glass portion 7 (or the outer peripheral portion thereof) in the sealing portion forming step will be described with reference to FIGS. 15 (a) and 15 (b). Note that this mechanism has been invented by the inventor of the present application, and it cannot be said that this is always the case. However, for example, as shown in FIG. 3A, it is true that the second glass portion 7 (or its peripheral peripheral portion) has a compressive stress (compressive strain), and the compressive stress is applied. It is also a fact that the pressure resistance is improved by the sealing part 2 including the part.

FIG. 15A schematically shows a cross-sectional configuration at the time when the second glass portion 7a in the state of the glass tube 70 is inserted into the first glass portion 8 in the state of the side tube portion 2 ′. 15 (b) schematically shows a cross-sectional configuration when the second glass portion 7a is softened to a molten state 7b in the configuration of FIG. 15 (a). In the present embodiment, the first glass portion 8 is composed of a quartz glass containing SiO ₂ or 99 wt%, and, second glass portion 7a is constituted by a Vycor glass.

First, as a premise, the presence of compressive stress (compression strain) often has a difference in the coefficient of thermal expansion between the materials in contact with each other. That is, the reason why compressive stress is applied to the second glass portion 7 provided in the sealing portion 2 is generally considered that there is a difference in thermal expansion coefficient between them. However, in this case, actually, there is no big difference between the thermal expansion coefficients of the two, and it can be said that they are almost equal. More specifically, when the thermal expansion coefficients of tungsten and molybdenum, which are metals, are about 46 × 10 ⁻⁷ / ° C. and about 37 to 53 × 10 ⁻⁷ / ° C., respectively, the first glass portion 8 The thermal expansion coefficient of quartz glass constituting the glass is about 5.5 × 10 ⁻⁷ / ° C., and the thermal expansion coefficient of Vycor glass is about 7 × 10 ⁻ that can be regarded as the same level as the thermal expansion coefficient of quartz glass. ⁷ / ° C. It is unlikely that a compressive stress of about 10 kgf / cm ² or more is generated between the two due to such a slight difference in thermal expansion coefficient. The difference between the two properties lies in the softening point or the strain point rather than the thermal expansion coefficient. From this point of view, it can be explained that compressive stress is applied by the following mechanism. The softening point and strain point of quartz glass are 1650 ° C. and 1070 ° C. (annealing point is 1150 ° C.), respectively, while the softening point and strain point of Vycor glass are 1530 ° C. and 890 ° C., respectively. (Annealing point is 1020 ° C.).

  When the first glass portion 8 (side tube portion 2 ′) is heated and shrunk from the outside in the state shown in FIG. 15A, the gap 7 c between the two is initially filled and the two come into contact with each other. After shrinking, as shown in FIG. 15 (b), when the first glass portion 8 having a higher softening point and a larger area in contact with the outside air is released from the softened state first (that is, when it hardens). However, the second glass portion 7b located on the inner side and having a low softening point is still softened (still in a molten state). The second glass portion 7b at this time has fluidity as compared with the first glass portion 8, and the thermal expansion coefficients of both at the normal time (when not in the softened state) are almost the same. However, it is considered that the properties (for example, elastic modulus, viscosity, density, etc.) of the two at this point are greatly different. And when time passes further and the 2nd glass part 7b which had fluidity cools, and the temperature of the 2nd glass part 7b is also less than a softening point, the 2nd glass part 7 will also be 1st. It will harden similarly to the glass part 8. Here, if the softening point of the 1st glass part 8 and the 2nd glass part 7 is the same, both glass parts will harden so that it may cool gradually from an outer side and a compression strain may not remain. In the case of the configuration of the present embodiment, the outer glass portion (8) hardens early, and after a while, the inner glass portion (7) hardens, so that the inner second glass portion 7 is compressed and strained. Seems to remain. Considering this, it may be said that the second glass portion 7 is in a state where a kind of pinching is indirectly performed.

  If such compressive strain remains, the close contact state between the two (7, 8) will usually end at a certain temperature due to the difference in thermal expansion coefficient between the two. In the case of the configuration of the form, since the thermal expansion coefficients of both are substantially equal, it is presumed that the close contact state of both (7, 8) can be maintained even if compressive strain exists.

Further, in order to give a compressive stress of about 10 kgf / cm ² or more to the second glass part 7, the strain point of the second glass part is compared with the lamp (lamp complete body) completed by the above-described manufacturing method. It has been found necessary to heat at a temperature higher than the temperature. It was also found that heating at 1030 ° C. for 2 hours or more is preferable. Specifically, the completed lamp 100 may be put in a furnace at 1030 ° C. and annealed (for example, vacuum baking or vacuum baking). In addition, the temperature of 1030 degreeC is an illustration, and should just be a temperature higher than the strain point temperature of the 2nd glass part (Vycor glass) 7. FIG. That is, it should be higher than the strain point temperature of Vycor 890 ° C. A preferable range is a temperature higher than the strain point temperature of Vycor of 890 ° C. and lower than the strain point temperature of the first glass part (quartz glass) (the strain point temperature of SiO ₂ is 1070 ° C.). In some cases, the inventor of the present application experimented at a temperature of about 0C.

For comparison, a high pressure discharge lamp that was not annealed was measured by a sensitive color plate method, and the second glass portion 7 was provided in the sealing portion of the high pressure discharge lamp. Nevertheless, a compressive stress of about 10 kgf / cm ² or more was not observed in the sealed portion.

  As long as the annealing (or vacuum baking) time is 2 hours or longer, there is no particular upper limit except for an upper limit from an economical viewpoint. What is necessary is just to set suitable time suitably in the range of 2 hours or more. Further, if the effect is observed even in less than 2 hours, heat treatment (annealing) in less than 2 hours may be performed. This annealing process may achieve a high purity of the lamp, in other words, a reduction in impurities. This is because it is considered that by annealing the finished lamp body, moisture (for example, moisture in Vycor) considered to have an adverse effect on the lamp can be discharged from the lamp. If the annealing is performed for 100 hours or longer, it is possible to almost completely remove the water in the Vycor from the lamp.

In the above description, the example in which the second glass portion 7 is made of Vycor glass has been described. However, SiO ₂ : 62 wt%, Al ₂ O ₃ : 13.8 wt%, CuO: 23.7 wt% are constituents. It was also found that even when the second glass part 7 is composed of glass (trade name: SCY2, manufactured by SEMCOM, strain point: 520 ° C.), a compressive stress is applied at least in the longitudinal direction.

  Next, referring to FIG. 16, a mechanism in which compressive stress is applied to the second glass portion 7 of the lamp when the lamp inferred by the inventor of the present application is annealed for a predetermined time at a predetermined temperature. explain.

  First, as shown in FIG. 16A, a completed lamp is prepared. The method for manufacturing the finished lamp is as described above.

  Next, when the lamp complete body is heated, as shown in FIG. 16B, mercury (Hg) 6 starts to evaporate. As a result, pressure is also applied to the inside of the arc tube 1 and the second glass portion 7. . The arrow in the figure represents the pressure (for example, 100 atmospheres or more) due to the mercury 6 vapor. The reason why the vapor pressure of mercury 6 is applied not only to the inside of the arc tube 1 but also to the second glass portion 7 is that there is a gap 13 in the sealing portion of the electrode rod 3 that is invisible.

  When the heating temperature is further raised and the heating is continued at a temperature exceeding the strain point of the second glass part 7 (for example, 1030 ° C.), the second glass part 7 is in a soft state and the vapor pressure of mercury is second. Therefore, compressive stress is generated in the second glass portion 7. The time for generating the compressive stress is estimated to be about 4 hours when heated at the strain point and about 15 minutes when heated at the annealing point, for example. This time is derived from the definitions of strain point and annealing point. That is, the strain point means a temperature at which internal strain can be substantially removed if kept at this temperature for 4 hours, and the annealing point means a temperature at which internal stress can be substantially removed if kept at this temperature for 15 minutes. From the point of view, the above time is estimated.

  Next, the heating is stopped and the finished lamp is cooled. Even after the heating is stopped, as shown in FIG. 16C, the mercury remains evaporated, so that the temperature of the second glass portion 7 becomes lower than the strain point while continuing to receive the pressure due to the mercury vapor. 19, the compressive stress remains in the second glass portion 7 not only in the longitudinal direction but also in the radial direction of the metal foil 4 (however, in the strain tester, the compressive stress in the longitudinal direction is left). Can only confirm).

Finally, when the cooling proceeds to about room temperature, a lamp 100 having a compressive stress of about 10 kgf / cm ² or more in the second glass portion 7 is obtained as shown in FIG. As shown in FIGS. 16B and 16C, since the vapor pressure of mercury applies pressure to both the second glass parts 7, according to this method, about 10 kgf is applied to both the sealing parts 2. A compressive stress of / cm ² or more can be applied reliably.

This heating profile is schematically shown in FIG. First, when heating is started (time O), the temperature reaches the strain point (T ₂ ) of the second glass portion 7 (time A). Next, at a temperature between the strain point of the second glass portion 7 (T ₂₎ and the strain point of the first glass portion 8 (T _1), holding the lamp a predetermined time. This temperature region can basically be regarded as a range in which only the second glass portion 7 can be deformed. During this holding, as shown in the schematic diagram of FIG. 18, a compressive stress is applied to the second glass portion 7 due to mercury vapor pressure (for example, 100 atm or more).

Note that applying the pressure to the second glass portion 7 by the mercury vapor pressure seems to be the most effective method of using the annealing treatment, but the lamp is held in the temperature range of T _{2 to} T ₁ in FIG. If it is possible to apply some force to the second glass part 7, not only the mercury vapor pressure but also the force (for example, by pressing the external lead 5), the second glass part 7 is applied to the second glass part 7. It is assumed that compressive stress can be applied.

Next, when the heating is stopped, the lamp is cooled, and after time B, the temperature of the second glass portion 7 is lower than the strain point (T ₂ ). Below the strain point (T ₂ ), the compressive stress of the second glass portion 7 remains. In this embodiment, after holding at 1030 ° C. for 150 hours, cooling (natural cooling) is applied to apply the compressive stress of the second glass portion 7 to leave it.

  With the mechanism described above, compressive stress is generated by the mercury vapor pressure. Therefore, the magnitude of the compressive stress depends on the mercury vapor pressure (in other words, the amount of enclosed mercury).

  In general, as the amount of mercury increases, the lamp easily bursts. However, when the sealing structure of this embodiment is used, the compressive stress increases as the amount of mercury increases, and the breakdown voltage improves. That is, according to the configuration of the present embodiment, as the amount of mercury is increased, a high withstand voltage structure can be realized. Therefore, stable lighting at an extremely high withstand voltage that cannot be realized with the current technology is enabled. .

  In the state shown in FIG. 4, it is also possible to use a long glass tube (long bicol tube) 70 as shown in FIG. The glass tube 70 shown in FIG. 6 has a small diameter at one end (that is, the end opposite to the arc tube portion 1 ′), whereby the glass tube 70 is fixed. As a fixing method, the external lead 5 may be pressed at a location where the diameter is reduced, or after the pipe 80 is substantially vertical, the location where the diameter of the glass tube 70 is reduced is a metal foil ( Molybdenum foil) may be hooked on the corner of 4.

According to the manufacturing method of the high-pressure discharge lamp of the present embodiment, mercury bromide (HgBr ₂ ) is introduced into the arc tube portion 1 ′ as a halogen precursor, so that the alteration of the second glass portion 7 is suppressed. Can do. As a result, a compressive strain can be effectively put into the second glass portion 7, and a high-pressure discharge lamp can be realized more reliably. Moreover, it can prevent that a crack arises between the 2nd glass part 7 and the 1st glass part 8. FIG.

(Embodiment 2)
A high-pressure discharge lamp according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 7 schematically shows the configuration of the high-pressure discharge lamp 200 of the present embodiment. The point that mercury bromide (HgBr ₂ ) is enclosed as a halogen precursor in the arc tube 1 of the lamp 200 is the same as the high-pressure discharge lamp 100 of the first embodiment. Mercury bromide (HgBr ₂ ) is omitted in the drawings in the present embodiment and the first embodiment.

  In order to further improve the pressure resistance of the lamp 100 of the first embodiment, as in the lamp 200 shown in FIG. 7, at least a part of the surface of the electrode rod 3 in the portion embedded in the sealing portion 2 is used. A metal film (for example, Pt film) 30 is preferably formed. The metal film 30 only needs to be made of at least one metal selected from the group consisting of Pt, Ir, Rh, Ru, and Re. For example, the metal film 30 may be a single layer made of a Pt layer, or from the viewpoint of adhesion, the lower layer may be an Au layer and the upper layer may be a Pt layer, for example.

  In the lamp 200, since the metal film 30 is formed on the surface of the electrode rod 3 in the portion embedded in the sealing portion 2, a minute crack is generated in the glass positioned around the electrode rod 3. Can be prevented. That is, in the lamp 200, in addition to the effect obtained by the lamp 100, an effect of preventing the occurrence of cracks can be obtained, whereby the pressure strength can be further improved. Hereinafter, the description of the effect of preventing cracks will be continued.

  In the case of a lamp without the metal film 30 on the electrode rod 3 located in the sealing portion 2, after forming the sealing portion in the lamp manufacturing process, the glass of the sealing portion 2 and the electrode rod 3 are brought into close contact with each other. During cooling, the two are separated due to the difference in thermal expansion coefficient between the two. At this time, a crack occurs in the quartz glass around the electrode rod 3. Due to the presence of this crack, the pressure resistance is lower than that of an ideal lamp without a crack.

  In the case of the lamp 200 shown in FIG. 7, since the metal film 30 having the Pt layer on the surface is formed on the surface of the electrode rod 3, the quartz glass of the sealing portion 2 and the surface of the electrode rod 3 (Pt layer) The wettability between is worse. In other words, the combination of platinum and quartz glass worsens the wettability between the metal and quartz glass than the combination of tungsten and quartz glass. It is. As a result, due to the poor wettability between the electrode rod 3 and the quartz glass, the separation between the two at the time of cooling after heating is improved, and it becomes possible to prevent the occurrence of fine cracks. The lamp 200 manufactured based on the technical idea of preventing the occurrence of cracks by utilizing such poor wettability exhibits a higher pressure strength than the lamp 100.

  Instead of the configuration of the lamp 200 shown in FIG. 7, the configuration of the lamp 300 shown in FIG. 8 may be used. In the configuration of the lamp 100 shown in FIG. 1, the lamp 300 is obtained by winding a coil 40 whose surface is covered with a metal film 30 around the surface of the electrode rod 3 in a portion embedded in the sealing portion 2. In other words, the lamp 300 has a configuration in which a coil 40 having at least a surface of at least one metal selected from the group consisting of Pt, Ir, Rh, Ru, and Re is wound around the base of the electrode rod 3. Yes. In the configuration shown in FIG. 8, the coil 40 is wound up to the portion of the electrode rod 3 located in the discharge space 10 of the arc tube 1. Also in the configuration of the lamp 300 shown in FIG. 8, the metal film 30 on the surface of the coil 40 can deteriorate the wettability between the electrode rod 3 and the quartz glass, and as a result, the generation of fine cracks can be prevented. it can.

  The metal on the surface of the coil 40 may be formed by plating, for example. As in the configuration shown in FIG. 7, here, the metal film 30 may be a single layer made of, for example, a Pt layer, or from the viewpoint of adhesion, the lower layer is an Au layer and the upper layer is, for example, a Pt layer. It may be. From the viewpoint of adhesion, it is preferable to first form an Au layer as a lower layer on the coil 40 and then form, for example, a Pt layer as an upper layer, but Pt (upper layer) / Au (lower layer) plating. A practically sufficient adhesion can be ensured even with the coil 40 subjected to only Pt plating without using the two-layer structure.

  In the case of a configuration in which at least one metal selected from the group consisting of Pt, Ir, Rh, Ru, Re (also referred to as “Pt etc.”) is provided on the surface of the electrode rod 3 or the surface of the coil 40, The significance that the second glass portion 7 exists around the metal foil 4 as in the configuration of the embodiment of the invention is very significant. This will be further explained. Since metal such as Pt may evaporate somewhat in the lamp manufacturing process (sealing process) due to heating during processing, if it diffuses to the metal foil 4, the adhesion between the metal foil and the glass is weakened. This can result in a decrease in breakdown voltage. However, when the second glass portion 7 is provided around the metal foil 4 as in the configuration of the present embodiment, and compressive strain is present there, the poor wettability between Pt and the glass is no longer present. As a result, it is possible to prevent a decrease in breakdown voltage caused by diffusion of Pt or the like.

In the configuration shown in FIG. 7 and FIG. 8, the halogen (more specifically, the halogen precursor) is enclosed in a form such as HgBr ₂ (at room temperature) rather than using a gas such as CH ₂ Br _2. Note that it is preferable to adopt a solid form. The reason is that metal such as Pt may be etched by the gaseous halogen in the same manner as when the Vycor glass reacts with the gaseous halogen and changes its quality when sealed.

  Also in the lamps 200 and 300 of the present embodiment, as shown in FIG. 6, the second glass portion 7 that covers the entire metal foil 4 is formed using the glass tube 70 that covers the entire metal foil 4. May be.

  Furthermore, the lamps 100, 200, and 300 according to the embodiment of the present invention can be combined with a reflecting mirror to form a mirrored lamp or a lamp unit.

  FIG. 9 schematically illustrates a cross section of a mirror-equipped lamp 900 including the lamp 100 of the present embodiment.

  The mirror-equipped lamp 900 includes a lamp 100 having a substantially spherical arc tube 1 and a pair of sealing portions 2, and a reflecting mirror 60 that reflects light emitted from the lamp 100. The lamp 100 is an example, and of course, the lamp 200 or 300 may be used. Further, the mirror-equipped lamp 900 may further include a lamp house that holds the reflecting mirror 60. Here, the thing provided with the lamp house is included in a lamp unit.

  For example, the reflecting mirror 60 reflects the radiated light from the lamp 100 so as to be a parallel light beam, a condensed light beam that converges to a predetermined minute region, or a divergent light beam that is equivalent to a divergent light beam that diverges from the predetermined minute region. It is configured. As the reflecting mirror 60, for example, a parabolic mirror or an ellipsoidal mirror can be used.

  In the present embodiment, a base 56 is attached to one sealing part 2 of the lamp 100, and the external lead (5) extending from the sealing part 2 and the base 56 are electrically connected. The sealing part 2 and the reflecting mirror 60 are fixed and integrated with, for example, an inorganic adhesive (for example, cement). A lead wire 65 is electrically connected to the external lead 5 of the sealing portion 2 located on the front opening side of the reflecting mirror 60, and the lead wire 65 is connected to the reflecting mirror 60 from the lead wire 5. It extends to the outside of the reflecting mirror 60 through the lead wire opening 62. For example, a front glass can be attached to the front opening of the reflecting mirror 60.

  Such a mirror-equipped lamp or lamp unit can be attached to an image projection apparatus such as a projector using liquid crystal or DMD, and is used as a light source for the image projection apparatus. Further, an image projection apparatus can be configured by combining such a mirror-equipped lamp or lamp unit and an optical system including an image element (such as a DMD (Digital Micromirror Device) panel or a liquid crystal panel). For example, it is possible to provide a projector using a DMD (digital light processing (DLP) projector) and a liquid crystal projector (including a reflective projector employing an LCOS (Liquid Crystal on Silicon) structure). Furthermore, the lamp of this embodiment and the lamp or lamp unit with a mirror are not only a light source for an image projection apparatus but also a light source for an ultraviolet stepper, a light source for a sports stadium, a light source for an automobile headlight, and a projector for illuminating a road sign. It can also be used as a light source.

(Other embodiments)
In the above embodiment, the mercury lamp using mercury as the luminescent material has been described as an example of the high-pressure discharge lamp. It can also be applied to a discharge lamp. For example, it can be applied to a high pressure discharge lamp such as a metal halide lamp or xenon in which a metal halide is sealed. This is because even with a metal halide lamp or the like, the higher the withstand voltage, the better. That is, it is possible to realize a highly reliable and long-life lamp by preventing leakage and cracking. Further, when the configuration of the above embodiment is applied to a metal halide lamp in which not only mercury but also a metal halide is enclosed, the following effects can be obtained. That is, by providing the second glass part 7, the adhesion of the metal foil 4 in the sealing part 2 can be improved, and the reaction between the metal foil 4 and the metal halide (or halogen and alkali metal). As a result, it is possible to improve the reliability of the structure of the sealing portion. In particular, when the second glass portion 7 is located in the portion of the metal rod 3 as in the configurations shown in FIGS. 1, 7, and 8, the glass of the metal rod 3 and the sealing portion 2 is made of glass. The second glass portion 7 can effectively reduce the penetration of the metal halide that enters through a slight gap between them and reacts with the metal foil 4 to cause embrittlement of the foil. Thus, the structure of the said embodiment is applicable suitably for a metal halide lamp.

  In recent years, the development of mercury-free metal halide lamps that do not enclose mercury is also progressing, but the technology of the above-described embodiment can also be applied to such mercury-free metal halide lamps. The details will be described below.

  As the mercury-free metal halide lamp to which the technique of the above embodiment is applied, in the configuration shown in FIG. 1, FIG. 7 or FIG. 8, mercury is not substantially enclosed in the arc tube 1, and at least the first One in which a halide of No. 1, a second halide, and a rare gas are encapsulated. At this time, the metal of the first halide is a light emitting substance, and the second halide has a vapor pressure higher than that of the first halide, and the metal of the first halide. In comparison, it is one or more halides of metals that do not easily emit light in the visible range. For example, the first halide is one or more halides selected from the group consisting of sodium, scandium, and rare earth metals. The second halide is one or a plurality of halides having a relatively high vapor pressure and hardly emitting light in the visible region as compared with the metal of the first halide. The specific second halide is at least one selected from the group consisting of Mg, Fe, Co, Cr, Zn, Ni, Mn, Al, Sb, Be, Re, Ga, Ti, Zr and Hf. Metal halide. A second halide containing at least Zn halide is more preferable.

As another example of combination, a translucent arc tube (airtight container) 1, a pair of electrodes 3 provided in the arc tube 1, and a pair of sealing portions 2 connected to the arc tube 1. In an arc tube 1 of a mercury-free metal halide lamp equipped with a light emitting material, ScI ₃ (scandium iodide) and NaI (sodium iodide) as light emitting materials, and InI ₃ (indium iodide) and TlI (substitute mercury materials). (Thallium iodide) and a rare gas (for example, 1.4 MPa Xe gas) as a starting auxiliary gas are enclosed. In this case, the first halide is ScI ₃ (scandium iodide) and NaI (sodium iodide), and the second halide is InI ₃ (indium iodide) and TlI (thallium iodide). Note that the second halide only needs to have a relatively high vapor pressure and take the place of mercury, so that, for example, Zn iodide is used instead of InI ₃ (indium iodide) or the like. May be.

  The reason why the technique of Embodiment 1 can be suitably applied to such a mercury-free metal halide lamp will be described next.

  First, in the case of a mercury-free metal halide lamp using an alternative substance of Hg (such as a halide of Zn), the efficiency is lower than that of a mercury-containing lamp. In order to increase the efficiency, it is very advantageous to increase the lighting operation pressure. In the case of the lamp of the above-described embodiment, since the structure has an improved breakdown voltage, a rare gas can be sealed at a high pressure, and thus the efficiency can be easily improved. Therefore, a practical mercury-free metal halide lamp can be easily realized. be able to. In this case, Xe having a low thermal conductivity is preferable as the rare gas.

  In the case of mercury-free metal halide lamps, it is necessary to enclose more halogen than mercury-containing metal halide lamps because mercury is not encapsulated. Therefore, the amount of halogen that reaches the metal foil 4 through the gap near the electrode rod 3 also increases, and the halogen reacts with the metal foil 4 (in some cases, the root portion of the electrode rod 3). It becomes weaker and more likely to leak. In the configuration shown in FIGS. 7 and 8, since the surface of the electrode rod 3 is covered with the metal film 30 (or the coil 40), the reaction between the electrode rod 3 and the halogen can be effectively prevented. Further, as shown in FIG. 1, in the case where the second glass portion 7 is located around the electrode rod 3, the second glass portion 7 intrudes halide (for example, Sc halide). It is possible to prevent the occurrence of leakage. Therefore, in the case of the mercury-free metal halide lamp having the structure of the above-described embodiment, higher efficiency and longer life can be achieved than the conventional mercury-free metal halide lamp. This is true for general illumination lamps. Speaking of lamps for car headlamps, there are the following advantages.

  When used as a headlight of a car, there is a demand to obtain 100% light at the next moment when the switch is turned on. In order to meet this requirement, it is effective to enclose a rare gas (specifically, Xe) at a high pressure. However, if Xe is sealed at a high pressure with a normal metal halide lamp, the possibility of explosion increases. This is not preferable as a lamp for a headlamp that requires a higher level of safety. That is, a headlight failure at night leads to a car accident. In the case of the mercury-free metal halide lamp having the structure of the above embodiment, since it has a structure with improved withstand voltage, the startability of lighting can be ensured even when encapsulating such high-pressure Xe while ensuring safety. Can be improved. In addition, since the life is extended, it can be more suitably applied for a headlamp.

  Further, in the above embodiment, the case where the mercury vapor pressure is about 20 MPa or about 30 MPa or more (in the case of a so-called ultra-high pressure mercury lamp) has been described. However, as described above, it is applied to a high-pressure mercury lamp having a mercury vapor pressure of about 1 MPa. It does not exclude doing. That is, the present invention can be applied to all high-pressure discharge lamps including ultra-high pressure mercury lamps and high-pressure mercury lamps. In addition, the mercury vapor pressure of what is called today's ultra-high pressure mercury lamp is 15 MPa or more (encapsulated mercury amount 150 mg / cc or more).

  The fact that the lamp can be stably operated even when the operating pressure is extremely high means that the reliability of the lamp is high. Therefore, the configuration of the present embodiment is applied to a lamp (the lamp operating pressure is about 30 MPa). Less than, for example, about 20 MPa to about 1 MPa), it is possible to improve the reliability of the lamp operating at the operating pressure.

  The technical significance of the lamp capable of realizing a high pressure strength will be further described as follows. In recent years, in order to obtain a high-power and high-power high-pressure mercury lamp, the development of a short arc type mercury lamp (for example, the distance between electrodes is 2 mm or less) with a short arc length (distance between electrodes) is progressing. In the case of the short arc type, it is necessary to enclose a larger amount of mercury than usual in order to prevent the electrode from evaporating faster with increasing current. As described above, since the conventional structure has an upper limit on the pressure resistance, there is also an upper limit (for example, about 200 mg / cc or less) in the amount of enclosed mercury, and it is possible to realize a lamp exhibiting further excellent characteristics. Restrictions were added. The lamp according to the present embodiment can remove such limitations in the prior art, and can promote the development of a lamp exhibiting excellent characteristics that could not be realized in the past. In the lamp according to the present embodiment, it is possible to realize a lamp with an enclosed mercury amount exceeding about 200 mg / cc or about 300 mg / cc or more.

  As described above, a technology capable of realizing an enclosed mercury amount of about 300 to 400 mg / cc or more (lighting operation pressure 30 to 40 MPa) is particularly a lamp at a level exceeding the lighting operation pressure 20 MPa (that is, today). Lamps having a lighting operating pressure exceeding 15 MPa to 20 MPa lamps (for example, lamps having a pressure of 23 MPa or more or 25 MPa or more) have the significance of ensuring safety and reliability. In other words, in the case of mass production of lamps, the characteristics of the lamps may inevitably vary. Therefore, even with a lamp whose lighting operating pressure is about 23 MPa, it is necessary to secure a breakdown voltage in consideration of the margin. The technology that can achieve a withstand pressure of 30 MPa or more has a great advantage from the viewpoint of actually supplying a product even for a lamp of less than 30 MPa. Of course, safety and reliability can be improved by producing a lamp that may have a withstand pressure of 23 MPa or less using a technique capable of achieving a withstand pressure of 30 MPa or more.

  Therefore, the configuration of this embodiment can improve the lamp characteristics from the viewpoint of reliability and the like. In the lamp of the above embodiment, the sealing portion 2 is manufactured by the shrink method, but may be manufactured by a pinching method. Further, although the double-end type high-pressure discharge lamp has been described, the technique of the above embodiment can be applied to a single-end type discharge lamp. In the embodiment described above, the second glass portion 7 is formed from, for example, a glass tube (70) made of Vycor, but it is not necessarily formed from a glass tube. It is not limited to a glass tube as long as it is not limited to a configuration that covers the entire periphery of the metal foil 4, as long as it is a glass structure that can contact the metal foil 4 and cause compressive stress to exist in a part of the sealing portion 2. For example, a glass structure having a “C shape” with a slit in a part of the glass tube 70 is also used. For example, a carat made of Vycor (glass piece or (Glass plate) may be arranged, or glass fiber made from Vycor, for example, may be arranged so as to cover the periphery of the metal foil 4. However, even if a glass powder, for example, a sintered glass body formed by compressing and sintering glass powder, is used instead of a glass structure, a compressive stress may exist in a part of the sealing portion 2. Because it is not possible, it is better not to use glass powder.

  In addition, the interval (arc length) between the pair of electrodes 3 may be a short arc type or a longer interval. The lamp of the above embodiment can be used in any lighting system of an AC lighting type and a DC lighting type. Further, the configuration and the modification examples shown in the above embodiment can be mutually adopted. In addition, although the sealing part structure containing the metal foil 4 was demonstrated, it is also possible to apply the structure of the said embodiment about the sealing part structure without foil. This is because even in the case of a sealing part structure without a foil, it is important to increase the breakdown voltage and to improve the reliability. More specifically, a single electrode rod (tungsten rod) 3 is used as the electrode structure 50 without using the molybdenum foil 4 as the electrode structure 50. The second glass portion 7 is disposed on at least a part of the electrode rod 3, the first glass portion 8 is formed so as to cover the second glass portion 7 and the electrode rod 3, and the sealing portion structure is formed. It is also possible to construct. In the case of this configuration, the external lead 5 can also be configured by the electrode rod 3.

  In the above-described embodiment, the discharge lamp has been described. However, the technique of the first embodiment is not limited to the discharge lamp, and any discharge lamp can be used as long as the lamp has a configuration in which the arc tube is hermetically sealed by a sealing portion (seal portion). The present invention can also be applied to lamps other than lamps (for example, light bulbs). A light bulb to which the technique of the first embodiment is applied is shown in FIGS.

  A light bulb 500 shown in FIG. 10 is a double-ended light bulb (for example, a halogen light bulb) in which the filament 9 is provided in the arc tube 1 in the configuration shown in FIG. The filament 9 is connected to an inner lead (internal lead wire) 3a. An anchor may be provided in the arc tube 1.

  The light bulb 600 shown in FIG. 11 is a single-end type light bulb as can be seen from the drawing. In this example, a single-ended halogen bulb is shown. The light bulb 600 includes, for example, a glass bulb 1 made of quartz, a sealing part 2 (first glass part 8, second glass part 7, molybdenum foil 4), filament 9, inner lead 31, anchor 32, outer lead ( External lead wire 5, insulator 51, and base 52. Even in such a halogen bulb, the problem of bursting is an important issue, and the technical significance of being able to prevent bursting by the technique of the above-described embodiment of the present invention is great.

  As mentioned above, although the preferable example of this invention was demonstrated, such description is not a limitation matter and of course, a various deformation | transformation is possible.

  As described above, in the high pressure discharge lamp manufacturing method, the high pressure discharge lamp and the lamp unit according to the present invention, the composition deformation of the second glass can be suppressed in the high pressure discharge lamp having the first and second glass portions. High pressure discharge lamps with high pressure strength can be obtained, and high pressure discharge lamps with high pressure strength can be effectively manufactured. In combination with general lighting and reflectors, projectors, automotive headlamps, etc. It is useful as a high-pressure discharge lamp used for

(A) And (b) is sectional drawing which shows typically the structure of the high pressure discharge lamp 100 concerning embodiment of this invention. (A) And (b) is a principal part enlarged view which shows typically distribution of the compressive strain along the longitudinal direction (electrode-axis direction) of the sealing part 2. FIG. (A) And (b) is process sectional drawing for demonstrating the predetermined process of the manufacturing method of the lamp | ramp 100. FIG. FIG. 6 is a process cross-sectional view for explaining a manufacturing method of the lamp 100. FIG. 6 is a process cross-sectional view for explaining a manufacturing method of the lamp 100. FIG. 6 is a process cross-sectional view for explaining a manufacturing method of the lamp 100. It is sectional drawing which shows typically the structure of the high pressure discharge lamp 200 concerning embodiment of this invention. It is sectional drawing which shows typically the structure of the high pressure discharge lamp 300 concerning embodiment of this invention. It is sectional drawing which shows the structure of the lamp | ramp 900 with a mirror typically. 3 is a cross-sectional view schematically showing a configuration of a light bulb 500. FIG. 2 is a perspective view schematically showing a configuration of a light bulb 600. FIG. It is sectional drawing which shows the structure of the conventional high pressure mercury lamp typically. (A) And (b) is a figure for demonstrating the principle of the distortion measurement by the sensitive color plate method using a photoelastic effect. (A) And (b) is a principal part enlarged view for demonstrating the reason why the compressive strength of the lamp | ramp 100 goes up by the compressive distortion having entered into the 2nd glass part. (A) And (b) is sectional drawing for demonstrating a compression distortion | strain insertion mechanism in the 2nd glass part. (A) to (d) are cross-sectional views for explaining a mechanism in which compressive stress is applied by annealing. It is a graph which shows typically the profile of a heating process (annealing process). It is the schematic for demonstrating the mechanism in which compressive stress enters into the 2nd glass part by mercury vapor. (A) is a figure which shows typically the compressive stress of the longitudinal direction which exists in a 2nd glass part, (b) is the sectional view on the AA line of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Arc tube 1 'Arc tube part 2 Sealing part 2' Side tube part 3 Electrode rod 4 Metal foil 5 External lead 6 Luminescent substance (mercury)
7 Second glass part 8 First glass part 9 Filament 10 Discharge space (in the tube)
DESCRIPTION OF SYMBOLS 11 Support member 12 Coil 50 Electrode structure 56 Base 60 Reflector 62 Lead wire opening 65 Lead wire 70 Glass tube 80 Glass tube for discharge lamp 82 Chuck 100, 200, 300 High pressure discharge lamp 500, 600 Light bulb (halogen light bulb)
900 Lamp with mirror (lamp unit)
1000 Super high pressure mercury lamp

Claims (15)

A method for producing a high-pressure discharge lamp, comprising: a light-emitting tube in which a light-emitting substance is sealed in a tube; and a sealing portion that maintains the airtightness of the light-emitting tube,
The method of manufacturing the high-pressure discharge lamp is as follows:
A step of preparing a discharge pipe glass pipe having an arc tube portion to be an arc tube of a high pressure discharge lamp and a side tube portion extending from the arc tube portion;
Introducing mercury bromide (HgBr ₂ ) into the arc tube portion;
Forming the sealing portion from the side tube portion,
The step of forming the sealing portion includes
A glass member made of a second glass having a softening point lower than that of the first glass constituting the side tube portion is inserted into the side tube portion, and then the side tube portion is heated to A step of closely contacting the side tube portion;
A heating step of heating a portion including at least the glass member and the side tube portion at a temperature higher than the strain point temperature of the second glass after the adhesion step.   The method for manufacturing a high-pressure discharge lamp according to claim 1, wherein the heating step is performed at a temperature lower than a strain point temperature of the first glass. A method for manufacturing a high-pressure discharge lamp, comprising: a light-emitting tube in which a light-emitting substance is sealed in a tube; and a pair of sealing portions extending from both ends of the light-emitting tube,
Preparing a discharge pipe glass pipe having an arc tube portion to be an arc tube of a high-pressure discharge lamp and a pair of side tube portions extending from both ends of the arc tube portion;
One side tube portion of the pair of side tube portions includes a glass tube made of a second glass having a softening point lower than that of the first glass constituting the side tube portion, and at least an electrode rod. Inserting the electrode structure, and then forming one sealing portion of the pair of sealing portions by heating and shrinking the side tube portion; and
After forming the one sealing portion, introducing a luminescent material and mercury bromide (HgBr ₂ ) into the arc tube portion;
After introducing the luminescent material, a glass tube made of the second glass and an electrode structure including at least an electrode rod are inserted into the other side tube portion of the one side, and then the side tube portion Forming the arc tube in which the other sealing portion with respect to the one and the luminescent material are sealed by heating and shrinking,
With respect to the complete lamp body in which both the sealing portion and the arc tube are formed, at a temperature higher than the strain point temperature of the second glass and a temperature lower than the strain point temperature of the first glass. And a heating step of heating a portion including at least the glass tube and the side tube portion.   The method for manufacturing a high-pressure discharge lamp according to claim 1 or 3, wherein the heating step is performed for 2 hours or more.   The said heating process is a manufacturing method of the high pressure discharge lamp of Claim 3 performed for 100 hours or more. When the sealing portion is measured using a sensitive color plate method using a photoelastic effect, the side tube portion of 10 kgf / cm ² or more and 50 kgf / cm ² or less is formed in the region constituted by the second glass. The method for manufacturing a high-pressure discharge lamp according to claim 3, wherein the heating step is performed so that a longitudinal compressive stress exists.   The method for manufacturing a high-pressure discharge lamp according to claim 6, wherein the compressive stress is generated for each of the pair of sealing portions. The heating in the heating step is performed by placing the lamp complete body in a furnace having a temperature higher than the strain point temperature of the second glass and lower than the strain point temperature of the first glass. The manufacturing method of the high pressure discharge lamp of Claim 3.   The method for manufacturing a high-pressure discharge lamp according to claim 8, wherein the furnace is in a vacuum or a reduced pressure state. The first glass contains 99% by weight or more of SiO ₂ ;
10. The high pressure according to claim 1, wherein the second glass includes at least one of 15 wt% or less of Al ₂ O ₃ and 4 wt% or less of B and SiO _2. A method for manufacturing a discharge lamp. The method for manufacturing a high-pressure discharge lamp according to claim 10, wherein the heating temperature in the heating step is 1030 ° C ± 40 ° C. The high-pressure discharge lamp is a high-pressure mercury lamp,
The method for manufacturing a high-pressure discharge lamp according to any one of claims 1 to 11, wherein mercury as the luminescent material is sealed in an amount of 150 mg / cm ³ or more based on an inner volume of the arc tube. A luminous tube in which a luminescent material is enclosed, and
A sealing portion for maintaining the airtightness of the arc tube,
The sealing portion includes a first glass portion extending from the arc tube, and a second glass portion provided on at least a part of the inside of the first glass portion, and
The second glass part is applied with a compressive stress in a direction in which at least the first glass part extends from the arc tube,
A high-pressure discharge lamp in which mercury bromide (HgBr ₂ ) is sealed in the arc tube. A luminous tube in which a luminescent material is enclosed, and
A pair of sealing portions for maintaining the airtightness of the arc tube,
Each of the pair of sealing portions includes a first glass portion extending from the arc tube and a second glass portion provided at least at a part of the inside of the first glass portion. And
Each of the pair of sealing portions has a portion to which a compressive stress is applied,
The compressive stress is 10 kgf / cm ² or more and 50 kgf / cm ² or less in a region corresponding to the second glass portion when the sealing portion is measured using a sensitive color plate method using a photoelastic effect. Yes,
In the arc tube, a pair of electrode rods are arranged facing each other,
Each electrode rod of the pair of electrode rods is connected to a metal foil,
The metal foil is provided in the sealing portion, and at least a connection portion between the metal foil and the electrode rod is located in the second glass portion,
A high-pressure discharge lamp in which mercury bromide (HgBr ₂ ) is enclosed as a halogen precursor in the arc tube.   A lamp unit comprising the high-pressure discharge lamp according to claim 13 and a reflecting mirror that reflects light emitted from the high-pressure discharge lamp.

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