JP2017162548A - Flashing discharge tube and method for manufacturing the same, and strobe device with flashing discharge tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a flashing discharge tube which can materialize the significant improvement in a high heat resistance property and a high thermal shock resistance property, and which can be formed inexpensively; a method for manufacturing the flashing discharge tube; and a strobe device with the flashing discharge tube.SOLUTION: A flashing discharge tube 1 is configured so that a pair of discharge electrodes consisting of an anode A and a cathode C are air-tightly sealed at both ends of a light transmissive envelope 2 with a xenon gas 3 filled in the envelope. The envelope 2 is formed by aluminosilicate glass. Of the discharge electrodes, at least the cathode C is air-tightly sealed in the aluminosilicate glass tube so as to have an outer diameter smaller than an inner diameter of the aluminosilicate glass tube, by locally heat-melting only a second end vicinity including a cathode bead 5 formed on an electrode pin and a second end of the aluminosilicate glass tube and thus causing the second end to sink into a substantially central portion of a side face of the cathode bead 5 to form a concave portion in the substantially central portion of the side face of the cathode bead 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a flash discharge tube using an aluminosilicate glass tube containing aluminosilicate as a main component and containing almost no alkali metal component, a method for manufacturing the same, and a strobe device equipped with the flash discharge tube.

  Conventionally, a flash discharge tube has been useful as a light source of a strobe device that is an artificial light source for illuminating a subject at the time of taking a photograph, for example, and forms a subject image in a camera that performs the above-described photography. As so-called photosensitive materials are increasingly digitized using electro-optical elements such as CCDs, the number of shots has increased dramatically. As a result, there has been a strong demand for significant improvement in the light-emission life durability characteristics of the previous strobe devices. It has been.

  By the way, in order to improve the light emission life durability characteristics of the strobe device, it is essential to improve the durability characteristics of the flash discharge tube which is a light source. It goes without saying that it will be detailed.

  Here, when looking at the configuration of the flash discharge tube, in the state where xenon gas is sealed inside both ends of the glass tube constituting the translucent envelope of the flash discharge tube, the electrode pin and A structure is known in which a pair of discharge electrodes consisting of a cathode formed mainly of a sintered body attached to the electrode pin and an anode formed mainly of the electrode pin itself are hermetically sealed. It has been strongly desired to strengthen the constituent materials including the glass tube. The material of the electrode pin must be selected from a material that can withstand this large current because the flash discharge is an arc discharge phenomenon and a large current flows instantaneously. In general, tungsten, which is a refractory metal, which is relatively easy to process into an electrode pin state, is used.

  Under such circumstances, the applicant of the present application has previously proposed a flash discharge tube and a light irradiation apparatus including the flash discharge tube in consideration of the above-mentioned request in Japanese Patent Application No. 2015-51572.

This proposal is to provide a light emitting device that is excellent in light emitting life durability against light emission and a short time repeated light emitting durability and is inexpensive, and a light irradiation device that is, for example, a strobe device equipped with the light emitting tube as a light source. Specifically, in the flash discharge tube having a configuration in which a pair of discharge electrodes are hermetically sealed at both ends of a light-transmitting envelope with xenon gas sealed therein. The envelope part surrounding the arc discharge region between the discharge electrodes is formed of aluminosilicate glass containing aluminosilicate as a main component and almost no alkali metal component. .
This aluminosilicate glass is a well-known borosilicate glass that has been conventionally used as a glass of a flash discharge tube envelope, that is, a thermal expansion coefficient similar to that of tungsten, and sodium oxide or alkali metal component. Compared to so-called tungsten sealing glass designed to lower the softening point by appropriately containing an alkali metal oxide such as potassium oxide, the softening point is high, thereby improving the heat resistance characteristics, In addition, although it contains almost no alkali metal component, the thermal expansion coefficient is increased, but the elution phenomenon of the alkali metal component into the glass tube due to the thermal shock associated with the light emission of the flash discharge tube can be drastically reduced, thereby greatly improving the thermal shock resistance. It can be improved.

  In other words, widely accepted in the field of glass so far, it is commonly used that the thermal expansion coefficient is small if the thermal expansion coefficient is small, and the practice of eg quartz glass with a small thermal expansion coefficient is used. Although it is different from the usual measures for strengthening glass tubes, it is possible to greatly improve the durability characteristics (heat resistance characteristics, thermal shock characteristics) against the phenomenon that occurred only in the envelope of the flash discharge tube, that is, thermal shock during arc discharge. Become.

In addition, since tungsten mentioned above is employ | adopted about an electrode pin, it cannot be overemphasized that consideration with respect to a thermal expansion coefficient is needed for realization of airtight sealing. That is, when looking at the characteristics of, for example, SCHOTT Glass 8253, which is known as an aluminosilicate glass, the softening point is about 1000 ° C., which is higher than about 700 to 830 ° C. of borosilicate glass containing an alkali metal component. The thermal expansion coefficient is 4.7 × 10 ⁻⁶ · K ^−1, which is close to that of tungsten, which is 4.4 to 4.5 × 10 ⁻⁶ · K ⁻¹ . It is large and also has characteristics larger than 3.2 to 4.1 × 10 ⁻⁶ · K ⁻¹ of borosilicate glass and 0.55 × 10 ⁻⁶ · K ^{−1 of} quartz glass.

  For this reason, a hermetic sealing process using a well-known bead winding configuration, for example, bead processing with borosilicate glass is performed in advance on tungsten, which is an electrode pin, and the outer surface of the bead and the inner surface of the glass tube are heated and melted to perform hermetic sealing. Assuming this process, during the cooling, the shrinkage of the glass (aluminosilicate glass) is larger than that of tungsten or borosilicate glass. As a result, stress in the direction to be separated is generated, and as a result, there is a possibility that a strong hermetic seal state may not be realized. Consideration is required.

Various methods have been conventionally known as such a method of consideration. For example, a plurality of heat treatments are used to hermetically seal quartz glass and tungsten, which are not aluminosilicate glasses, but have different thermal expansion coefficients. Prepare a relay valve composed of glass tubes with different expansion coefficients in advance, weld one end of the relay valve and one end of the quartz glass tube, and then add a thermal expansion coefficient to the other end of the relay valve. By welding an end bulb formed from a conventional borosilicate glass that approximates that of tungsten and then hermetically sealing the end bulb and tungsten through a heating process, resulting in a quartz glass tube A method of indirectly hermetically sealing tungsten and tungsten is known. (Patent Document 1)
In consideration of the fact that tungsten as an electrode is expensive and difficult to seal, it is composed of a plurality of layers having different expansion coefficients on both end faces of a glass tube as a discharge tube made of quartz glass or hardened glass. A circular shoulder formed opposite to the end face of the glass tube at the time of forming a sintered intermediate formed by sintering the glass powder is bonded via a glass brazing ring as a brazing surface, and the other is the glass tube Adhering via an organic adhesive at the end of the tube peripheral surface formed so as to be in contact with the other end surface of the tube, the electrode lead wire embedded in these sintered intermediates and the previous glass tube are hermetically bonded Gas discharge flash tubes are also well known. (Patent Document 2)
Of course, the earlier application by the present applicant is no exception, and the hermetically sealed structure is one where the end surface of the aluminosilicate glass tube and the end surface of the bead made of borosilicate glass (tungsten sealed glass) are butt-matched. The other is formed of borosilicate glass and has the same inner and outer diameters including the same inner and outer diameters of the aluminosilicate glass tube, and is melt-bonded to the other end of the aluminosilicate glass tube via an end face. And a structure in which the inner wall surface of the bonded glass tube and the side surface portion of the bead made of borosilicate glass are heat-welded.

Japanese Patent No. 5262911 Japanese Patent Publication No. 61-57653

  The flash discharge tube disclosed in Patent Document 1 is a quartz glass tube having a small thermal expansion coefficient, a high thermal shock resistance and a large mechanical strength in order to reinforce the glass tube constituting the envelope, or this quartz tube. In order to use a glass tube having a durability function equivalent to that of the glass tube, considering the difference in thermal expansion coefficient between the electrode pin and the glass tube constituting the envelope, both ends of the glass tube constituting the envelope are provided. Since the structure using the intermediate glass body is provided, a complicated processing step for forming the intermediate glass body is required, and there is a problem in that the flash discharge tube is greatly increased in cost. In addition, the example which employ | adopted the joining glass tube in the prior application by this applicant also requires the joining process process of this joining glass tube, and had the subject by a cost side like the cited reference 1.

  Reference 2 starts from the fact that tungsten is expensive and difficult to braze, and it is premised on the use of inexpensive nickel, nickel-iron alloy, or nickel-iron-cobalt alloy as an electrode. In addition, one of the sintered glass bodies (intermediate bodies) obtained by sintering glass powder that can be manufactured at low cost by a machine is connected to a glass tube via a glass brazing ring. For this reason, it is possible to obtain a highly durable discharge tube in which the glass tube is reinforced by using quartz glass as the glass tube, but the electrode material is not tungsten which is a refractory metal. Therefore, for example, when the input load to the electrode becomes large, for example, when high power is input, it is considered that the damage to the electrode is large and it melts relatively easily. When it sees, it was hard to say that the high durability characteristic was fully implement | achieved compared with the case where tungsten is used as an electrode.

  In view of the above problems, the present invention realizes a flash discharge tube that can achieve a significant improvement in high heat resistance and high thermal shock resistance with respect to a borosilicate glass tube, and can be formed at low cost, a method for manufacturing the same, and the flash It is an object of the present invention to provide a strobe device including a discharge tube.

  A flash discharge tube according to the present invention is a flash discharge tube in which discharge electrodes are hermetically sealed at both ends of a light-transmitting envelope in a state where xenon gas is sealed inside the envelope. Is composed of an aluminosilicate glass tube containing aluminosilicate as a main component and containing almost no alkali metal component, and the discharge electrode is composed of a first electrode pin and borosilicate glass, and the first electrode pin is formed of the aluminosilicate glass tube. The first bead is formed of a first bead that is directly wound and sealed to have an outer diameter less than the inner diameter, and is hermetically sealed. The first outer diameter is substantially equal to the outer diameter of the aluminosilicate glass tube. An aluminosilicate comprising an anode bead comprising a second bead that is formed by being wound around the bead with a length shorter than the axial length of the first bead and hermetically sealed; An anode that is hermetically bonded to the aluminosilicate glass tube by being melt-bonded to an end portion of the second bead forming the anode bead at one end of the glass tube, a second electrode pin, and borosilicate glass A cathode bead that is formed by being directly wound around the second electrode pin so as to have an outer diameter less than the inner diameter of the aluminosilicate glass tube, and is hermetically sealed, and is fixed to the tip of the second electrode pin The other end portion of the aluminosilicate glass tube including the other end portion of the aluminosilicate glass tube is heated and melted so that the other end portion is submerged in a substantially central portion of the side surface of the cathode bead. By forming a recess in the center, the aluminosilicate glass tube and a cathode hermetically sealed are formed.

  According to this configuration, the anode and the aluminosilicate glass tube are welded by heat welding in the axial direction instead of the radial direction of the aluminosilicate glass tube, which is the thickness portion of the end surface of the second bead and the one end surface of the aluminosilicate glass tube. As a result, the influence on the welded portion between the first bead and the electrode pin can be reduced. As a result, there is a problem such as a leak due to a peeling phenomenon that may occur due to a difference in thermal expansion coefficient. Occurrence can be suppressed.

  Further, the welding of the cathode and the aluminosilicate glass tube is performed by heating and melting only the vicinity of the tube end including the substantially central portion of the side surface of the cathode bead and the other end surface of the aluminosilicate glass tube. Since it is realized by being embedded so as to form a recess in the substantially central part, the influence of heating to the side part other than the substantially central part can be reduced, and the difference in thermal expansion coefficient can be achieved without using a bonded glass tube. As a result, it is possible to suppress the occurrence of inconveniences that may occur due to this, and as a result, a difficult processing step for joining the bonded glass tubes becomes unnecessary, and thus the process can be simplified, whereby a flash discharge tube can be formed at a low cost. become.

  That is, according to the structure of claim 1, the envelope of the flash discharge tube is called the thermal shock at the time of arc discharge by forming the envelope of the flash discharge tube with an aluminosilicate glass tube containing almost no alkali metal component. Achieving significant improvements in durability characteristics (heat resistance characteristics, thermal shock characteristics) against phenomena that have occurred only in the vessel, while suppressing the occurrence of inconveniences that may arise due to differences in thermal expansion coefficients, and at low cost Become. Therefore, it is possible to realize at a low cost a significant improvement in the light emission life durability characteristics of a flash discharge tube that is useful as a light source of a strobe device.

  The invention according to claim 2 is characterized in that the outer surface of the envelope is provided with a transparent conductive film to which a trigger voltage is applied.

  According to such a configuration, the same trigger voltage application configuration as before can be realized.

  The invention according to claim 3 is characterized in that a silicon dioxide film having a thickness of 130 to 400 nm formed by applying and baking a silanol solution on the inner surface of the envelope is provided.

  According to such a configuration, since the envelope is an aluminosilicate glass tube having a softening point higher than that of the borosilicate glass tube containing an alkali metal component and having a lowered softening point, the firing temperature of the silanol solution is increased. Therefore, a strong silicon dioxide film having a thickness of 130 to 400 nm can be formed on the inner surface of the envelope.

  According to a fourth aspect of the present invention, there is provided a strobe device including the flash discharge tube according to any one of the first to third aspects as a light source.

  According to such a configuration, an aluminosilicate glass tube containing almost no alkali metal component is used as an envelope constituting an arc discharge space, and a flash discharge tube having greatly improved heat resistance and thermal shock characteristics is used as a light source. Therefore, it is possible to provide a strobe device that is excellent in the light emission life durability characteristics and the short-time repeated light emission durability characteristics.

  According to a fifth aspect of the present invention, there is provided a method of manufacturing a flash discharge tube according to the present invention, wherein both ends of a translucent envelope made of an aluminosilicate glass tube containing aluminosilicate as a main component and containing almost no alkali metal component, A method of manufacturing a flash discharge tube in which a discharge electrode is hermetically sealed with a xenon gas sealed therein, wherein a first bead made of borosilicate glass is used as a first electrode pin and is less than the inner diameter of the aluminosilicate glass tube. And the second bead made of borosilicate glass is wound around the first bead so as to have an outer diameter substantially equal to the outer diameter of the aluminosilicate glass tube. An anode forming step of forming an anode by winding it at a length shorter than the axial length; and a cathode bead made of borosilicate glass on the second electrode pin. A cathode forming step of forming a cathode by directly winding the glass tube so as to have an outer diameter smaller than the inner diameter of the glass tube, and fixing a metal sintered body to the tip of the second electrode pin, and forming the anode bead An anode sealing step for hermetically sealing the aluminosilicate glass tube and the anode by melt-bonding an end surface of the second bead and one end of the aluminosilicate glass tube; and the other end of the aluminosilicate glass tube Is positioned in the vicinity of the central portion of the side surface of the cathode bead, and only the vicinity of the other end is heated and melted in a state where the xenon gas is sealed inside the aluminosilicate glass tube, and the other end is heated to the cathode bead. A cathode sealing step of hermetically sealing the aluminosilicate glass tube and the cathode by being embedded so as to form a recess at a substantially central portion of the side surface of Characterized by comprising a.

  According to this configuration, the anode and the aluminosilicate glass tube are welded by heat welding in the axial direction instead of the radial direction of the aluminosilicate glass tube, which is the thickness portion of the end surface of the second bead and the one end surface of the aluminosilicate glass tube. As a result, the influence on the welded portion between the first bead and the electrode pin can be reduced, and as a result, the occurrence of inconveniences such as leakage due to a peeling phenomenon that may occur due to a difference in thermal expansion coefficient is suppressed. It will be possible.

  Further, the welding of the cathode and the aluminosilicate glass tube is performed by heating and melting only the vicinity of the tube end including the substantially central portion of the side surface of the cathode bead and the other end surface of the aluminosilicate glass tube. Since it is realized by being embedded so as to form a recess in the side surface, it is possible to reduce the influence of heating to other than the substantially central portion of the side surface portion, thereby causing a difference in thermal expansion coefficient without using a bonded glass tube. The occurrence of inconvenience that may be feared can be suppressed. As a result, a simple process that does not require a difficult processing step for joining the joined glass tubes can be achieved, and the flash discharge tube can be formed at a low cost.

  That is, according to the manufacturing method of claim 5, there is a disadvantage that a flash discharge tube using an aluminosilicate glass tube containing almost no alkali metal component as an envelope may be caused due to a difference in thermal expansion coefficient. This can be realized at a low cost while suppressing the occurrence.

  According to a sixth aspect of the present invention, there is provided a flash discharge tube comprising: a pair of discharge electrodes each including an anode and a cathode, hermetically sealed at both ends of a translucent envelope, with xenon gas sealed therein. The envelope is a flash discharge tube made of an aluminosilicate glass tube containing aluminosilicate as a main component and containing almost no alkali metal component, and at least the cathode of the discharge electrode includes an electrode pin and a boron. A cathode bead made of silicate glass and directly wound around the electrode pin so as to have an outer diameter less than the inner diameter of the aluminosilicate glass tube and hermetically sealed, and a fired electrode fixed to the tip of the electrode pin The tube end portion is substantially in the side surface of the cathode bead by locally heating and melting the central portion of the side surface of the cathode bead and the vicinity of the end portion of the aluminosilicate glass tube. Was sink into parts, characterized in said aluminosilicate glass tube and be hermetically sealed by forming a recess on a side surface substantially central portion of the cathode bead.

  According to such a configuration, the welding between the cathode and the aluminosilicate glass tube is performed by heating and melting only the vicinity of the tube end including the substantially central portion of the side surface of the cathode bead and the end surface of the aluminosilicate glass tube. Because it is realized by submerging so as to form a recess in the substantially central part, the influence of heating to the side part other than the substantially central part can be reduced, thereby causing a difference in thermal expansion coefficient without using a bonded glass tube Therefore, it is possible to suppress the occurrence of inconvenience that may occur as a result, and as a result, it is possible to make a simple process that does not require a difficult processing step for joining the bonded glass tubes, thereby enabling a flash discharge tube to be formed at a low cost. Become.

  According to a seventh aspect of the present invention, there is provided a method of manufacturing a flash discharge tube according to the present invention, wherein both ends of a translucent envelope made of an aluminosilicate glass tube containing aluminosilicate as a main component and containing almost no alkali metal component, A method of manufacturing a flash discharge tube in which a pair of discharge electrodes consisting of an anode and a cathode is hermetically sealed in a state where xenon gas is sealed inside, wherein at least a cathode bead made of borosilicate glass is used as an electrode pin. A cathode forming step of forming a cathode by directly winding the silicate glass tube so that the outer diameter is less than the inner diameter of the silicate glass tube and fixing the metal sintered body to the tip of the electrode pin; and other than the aluminosilicate glass tube In the state where the end is positioned in the vicinity of the substantially central portion of the side surface of the cathode bead and the xenon gas is sealed inside the aluminosilicate glass tube A cathode that hermetically seals the aluminosilicate glass tube and the cathode by heating and melting only the vicinity of the other end portion and by inserting the other end portion into a substantially central portion of the side surface of the cathode bead so as to form a recess. And a sealing step.

  According to such a configuration, the welding of the cathode and the aluminosilicate glass tube is performed by heating and melting only the vicinity of the tube end including the substantially central portion of the side surface of the cathode bead and the other end surface of the aluminosilicate glass tube. Since it is realized by sinking so as to form a recess in the substantially central portion of the side surface, the influence of heating to other than the substantially central portion of the side surface portion can be reduced, thereby making it possible to reduce the difference in thermal expansion coefficient without using a bonded glass tube. The occurrence of inconveniences that may occur due to this can be suppressed, and as a result, a simple process that does not require a difficult processing step for joining the joined glass tubes can be achieved, and the flash discharge tube can be formed at low cost. .

  According to the flash discharge tube and the method of manufacturing the flash discharge tube of the present invention, the envelope of the flash discharge tube is composed of an aluminosilicate glass tube that hardly contains an alkali metal component, so that the thermal shock during arc discharge is called. While significantly improving durability characteristics (heat resistance characteristics, thermal shock characteristics) against phenomena that occurred only in the envelope of the flash discharge tube, while suppressing the occurrence of inconveniences that may arise due to differences in thermal expansion coefficients, As a result, it has the effect of providing an inexpensive flash discharge tube that is excellent in lifetime durability against light emission and short-term repeated emission durability.

  According to the stroboscopic device of the present invention, the flash discharge tube according to the present invention having greatly improved heat resistance and thermal shock characteristics is used as a light source. It has the effect that a device can be provided.

Schematic including a partial cross section showing an embodiment of a flash discharge tube according to the present invention Schematic showing an example of the manufacturing process of the anode of the flash discharge tube according to the embodiment Schematic showing a manufacturing process example of the cathode of the flash discharge tube according to the embodiment Schematic showing a manufacturing process example of a flash discharge tube according to the embodiment The schematic block diagram which shows one Embodiment of the strobe device which is an example of the light irradiation apparatus using the flash discharge tube concerning this invention

  Hereinafter, a flash discharge tube according to the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view including a partial cross section showing an embodiment of a flash discharge tube according to the present invention. As shown in the drawing, the flash discharge tube 1 is disposed at both ends of an envelope 2. 2, an electrode pin 6 that forms part of the discharge electrode A (anode) via the anode bead 4 with the xenon gas 3 sealed, and a part of the discharge electrode C (cathode) via the cathode bead 5. Is formed by hermetically sealing the electrode pins 7 forming the.

The envelope 2 of the flash discharge tube 1 according to the present invention is composed of an aluminosilicate glass tube (for example, Glass 8253 manufactured by SCHOTT) containing almost no alkali metal component, and the anode bead 4 and the cathode bead 5 are softened. It consists of a borosilicate glass tube designed to have a low point. (For example, SCHOTT Glass 8487)
By the way, although the aluminosilicate glass tube itself is a conventionally well-known glass tube, the present invention employs a glass tube containing almost no alkali metal component as described above, that is, the alumino glass employed in the present invention. The silicate glass tube is an alkali metal oxide-free aluminosilicate glass tube that contains almost no alkali metal component, and its component composition is about 20 w% aluminum oxide, about 60 w% silicon dioxide, and most of the remainder. It is a glass configured to contain less than 0.03 w% of the alkali metal oxide, which is an alkali metal component, containing an alkaline earth metal occupying as a main composition.

As a specific example, looking at the composition of the previous SCHOTT Glass 8253, 16.5 w% aluminum oxide, 61 w% silicon dioxide, 13 w% calcium oxide as an alkaline earth metal oxide, 8 w% barium oxide, The alkali metal oxide is configured to contain less than 0.02 w% sodium oxide and the like, and the alkali metal oxide is set to be less than 0.03 w% in total. Regarding the characteristics of the glass 8253, the softening point is about 1000 degrees, which is higher than about 700 to 830 degrees of borosilicate glass containing an alkali metal component, and the thermal expansion coefficient is 4.7 × 10 ^−6. K- ¹ , which is larger than 3.2 to 4.1 × 10 ⁻⁶ · K ⁻¹ of borosilicate glass and 0.55 × 10 ⁻⁶ · K ^{−1 of} quartz glass.

The discharge electrode A which is an anode is composed of an electrode pin 6 to which the anode bead 4 is welded and an external pin 8 welded to the electrode pin 6 as shown in the figure. Further, the electrode pin 6 has a thermal expansion coefficient. It is 4.4 to 4.5 × 10 ⁻⁶ · K ⁻¹ , and is composed of tungsten having a very high melting point of about 3400 ° C. The anode bead 4 is made of a conventionally known borosilicate glass (for example, Glass 8487 manufactured by SCHOTT), and the external pin 8 is made of nickel-based metal such as nickel.

  Further, the anode bead 4 is formed of a first bead 4a that is directly welded to the electrode pin 6 and a second bead 4b that is welded to the outside of the first bead 4a. The second bead 4b is configured such that the outer diameter of the end portion is substantially equal to the same as the outer diameter of the aluminosilicate glass tube constituting the envelope 2, and as described later, The hermetic sealing between the envelope 2 and the electrode pin 6 is indirectly realized by being melt-bonded to the thickness portion of the end surface of the envelope 2 (aluminosilicate glass tube) via the end surface.

  The discharge electrode C, which is a cathode, was welded to an electrode pin 7 on which a cathode bead 5 is hermetically welded as shown in the figure, and a sintered electrode 9 and an electrode pin 7 attached to the electrode pin 7 by a caulking method or the like. The cathode bead 5, the electrode pin 7 and the external pin 10 are made of borosilicate glass, tungsten, and nickel-based metal, respectively, like the discharge electrode A. Yes.

  As shown in the cross section in FIG. 1, the cathode bead 5 is directly wound around the electrode pin 7 so as to have a side portion outer diameter that is less than the inner diameter of the envelope 2 (aluminosilicate glass tube). By locally heating the central portion of the side surface together with the vicinity of the end portion of the envelope 2, the tube end portion of the envelope 2 is submerged in the substantially central portion of the side surface portion to form a recess. The envelope 2 is hermetically sealed, thereby indirectly realizing the hermetic seal between the envelope 2 and the electrode pins 7.

  Next, an outline of a process for manufacturing the flash discharge tube 1 according to the first embodiment of the present invention will be briefly described with reference to FIGS.

  2 (a) and 2 (b) show a process schematic diagram for manufacturing the discharge electrode A as an anode, and FIGS. 3 (a) and 3 (b) show a process schematic diagram for manufacturing a discharge electrode C as a cathode. 4 (a) and 4 (b) show process schematic diagrams for manufacturing the flash discharge tube 1 according to the first embodiment of the present invention using the process members manufactured in FIGS.

Both the discharge electrodes A and C shown in FIGS. 2 and 3 have a hollow cylindrical shape on tungsten having a thermal expansion coefficient of 4.4 to 4.5 × 10 ⁻⁶ · K ^{−1 as} the electrode pins 6 and 7. An anode bead 4 (first bead 4a and second bead 4b) and cathode bead 5 made of borosilicate glass having a thermal expansion coefficient of 3.2 to 4.1 × 10 ⁻⁶ · K ⁻¹ are shown in FIG. , Moved in the direction indicated by the arrow in FIG. 3 (a), and then inserted, and then heated by bead heating burners B1 and B2 as shown in FIG. 2 (b) and FIG. 3 (b), for example. By doing so, it is melt-bonded to the previous electrode pins 6 and 7.

  That is, the discharge electrode A is directly wound around the electrode pin 6 made of tungsten so that the first bead 4a made of borosilicate glass has an outer diameter smaller than the inner diameter of the envelope 2, and the second electrode 4 made of borosilicate glass is also formed. The bead 4b is wound around the first bead so as to have an outer diameter substantially equal to the outer diameter of the envelope 2 with a length shorter than the axial length of the first bead.

  The discharge electrode C is directly wound around the electrode pin 7 made of tungsten so that the cathode bead 5 made of borosilicate glass has an outer diameter smaller than the inner diameter of the envelope 2.

At this time, the difference between the thermal expansion coefficients of the electrode pins 6 and 7 and the anode bead 4 and the cathode bead 5 is small, specifically, it is set to 1 × 10 ⁻⁶ · K ⁻¹ or less. It is possible to prevent the occurrence of inconvenience based on the difference in thermal expansion coefficient during melt bonding by heating.

  As shown in FIG. 3B, the discharge electrode C is completed by attaching the sintered electrode 9 to the electrode pin 7 through a known caulking process (not shown).

  Further, it is described in detail that a transparent conductive film functioning as a trigger electrode to which a trigger voltage is applied may be formed on the envelope 2 in a predetermined region on the outer surface by a known method as necessary. Needless to do.

  Next, as shown in FIG. 4, the discharge electrodes A and C manufactured as described in FIGS. 2 and 3 are combined as follows to complete the flash discharge tube 1 according to the present invention.

  First, the discharge electrode A which is an anode is moved in the direction of the arrow in FIG. 4A, and the end face of the second bead 4b forming the anode bead 4 is brought into contact with the one end 2a of the envelope 2, and thereafter For example, the end face of the second bead 4b and one end portion 2a of the envelope 2 are melt-bonded through the thickness (end face) of the end portion of the envelope 2 by heating with the burner B3, whereby the anode The discharge electrode A is hermetically sealed to the envelope 2 through the anode bead 4.

  Next, as shown in FIG. 4 (a), the discharge electrode C is moved in the direction of the arrow, and the outer end 2b of the envelope 2 is positioned in the vicinity of the substantially central portion of the side surface of the cathode bead 5. The envelope 2 is filled with a desired amount of xenon gas 3, and only the vicinity of the other end 2b is locally heated and melted by, for example, a burner B4. The other end 2b of the envelope 2 heated and melted is composed of the aluminosilicate glass constituting the envelope 2 and the borosilicate glass constituting the cathode bead 5 in the cooling process after the heating is stopped. The cathode bead 5 sinks into the substantially central portion of the side surface of the cathode bead 5 based on the difference in thermal expansion coefficient of the cathode bead 5, and a recess is formed in the substantially central portion of the side surface of the cathode bead 5. The envelope 2 is hermetically sealed.

  Thereafter, although not shown in the drawing, the steps of setting the length of the external pins 8 and 10 to a desired length, the step of applying preliminary solder to the external pins 8 and 10 and the like are performed as necessary. The flash discharge tube 1 according to the present invention shown in FIG.

  As described above, the embodiment of the flash discharge tube 1 according to the present invention is configured without using an intermediate glass body or a stepped glass tube that requires a complicated processing step. It is clear that the manufacturing process described in 4 etc. can be simplified, and as a result, the flash discharge tube 1 according to the present invention can be provided at low cost.

  The flash discharge tube according to the present invention is not limited to the above-described embodiment. For example, the hermetically sealing discharge electrode A and the xenon gas sealing method can be variously changed as follows. Needless to say, it can be done.

  That is, in the above-described embodiment, the discharge electrode A is directly melt-bonded to one end of the envelope 2 through the thickness thereof, but the outer diameter of the anode bead 4 is set to the cathode bead. The outer diameter of the envelope 2 is formed to be smaller than the inner diameter of the envelope 2 and one end portion of the envelope 2 is disposed so as to be positioned at the substantially central portion of the side surface of the anode bead 4. It goes without saying that the gas-sealing configuration of the discharge electrode A serving as the anode can be changed to the same hermetic-sealing configuration as the discharge electrode C serving as the cathode by heating and melting only (local heating).

  At this time, each of the anode bead 4 and the cathode bead 5 is elongated in the axial direction of the envelope 2, for example, formed so as to have a dimension more than twice the inner diameter, thereby being sealed with the envelope 2. Of course, it may be configured so that the melt-bonded portion between the anode bead 4 and the cathode bead 5 and the electrode pins 6 and 7 exists inside and outside the envelope 2 except the portion.

  Further, as another example of a method for realizing the hermetic sealing process while enclosing the xenon gas 3 in the envelope 2 of the discharge electrode C described above, for example, a carbon heater is used instead of the burner B4. 4 includes the envelope 2 with the discharge electrode A sealed as shown in FIG. 4 excluding the burner B4, the discharge electrode C and the carbon heater, and a working space in which the inside can be evacuated and filled with xenon gas at a predetermined pressure. In the vacuum vessel, the end of the envelope 2 is disposed so as to be positioned at the substantially central portion of the side surface of the cathode bead 5 of the discharge electrode C. In this vacuum vessel, the xenon gas is filled and the discharge is performed by the carbon heater. Of course, it is possible to employ a method of performing local heating and fusion bonding between the cathode bead 5 of the electrode C and the envelope 2.

  Further, it goes without saying that a silicon dioxide film formed by applying and baking a silanol solution on the inner surface of the envelope 2 may be formed as necessary.

  At this time, the softening point of the aluminosilicate glass tube is higher than that of the borosilicate glass tube, and thus the above silanol solution firing operation is carried out at a higher temperature than when applied to the borosilicate glass tube and fired. In addition, since the aluminosilicate glass tube forming the envelope 2 of the flash discharge tube according to the present invention does not substantially contain an alkali metal component as described above, the previous silanol solution is fired. Depending on the working temperature, the components of the silanol solution can be diffused into the aluminosilicate glass tube, unlike the firing operation with a borosilicate glass tube containing an alkali metal component.

  Therefore, by setting the firing temperature of the silanol solution to a temperature higher than that for the borosilicate glass tube and a temperature at which the silanol solution component diffuses inside the aluminosilicate glass tube, the thickness is as strong as 130 to 400 nm. Thus, a silicon dioxide film can be formed on the inner surface of the envelope 2, and as a result, a flash discharge tube having further excellent durability can be obtained.

  Next, an embodiment of a strobe device according to the present invention will be described.

  FIG. 5 is a schematic configuration diagram showing an embodiment of a strobe device S using the flash discharge tube 1 according to the present invention.

  As shown in the figure, a strobe device S according to an embodiment of the present invention includes a flash discharge tube 1 according to the present invention, which serves as a light source for illuminating a subject 12, and light emitted from the flash discharge tube 1. Reflective umbrella 13 guided toward the direction of the subject 12, an optical member 14 disposed between the flash discharge tube 1 and the subject 12, light in a short wavelength region, for example, light having a wavelength of 400 nm or less, and light incident through the optical member 14 The optical control means 15 for controlling the emission direction, the emission angle, and the like, and the light emission operation control means 16 for controlling the light emission operation of the flash discharge tube 1 are provided.

  For this reason, when the flash discharge tube 1 performs a light emission operation by the light emission operation control means 16, the emitted light emitted from the flash discharge tube 1 is reflected directly and by the reflector 13 and reaches the optical member 14 to reach a short wavelength. The light of the region is controlled to light that is blocked (for example, light that does not include light having a wavelength of 400 nm or less), and the irradiation angle is controlled by the optical control unit 15 so that the subject 12 is irradiated.

  At this time, the flash discharge tube according to the present invention, that is, the envelope is constituted by an aluminosilicate glass tube as a light source of the strobe device according to the present invention, and the elution phenomenon of the alkali metal component is drastically reduced, thereby achieving high heat resistance and high performance. Thermal shock characteristics can be realized. As a result, the flash discharge tube has excellent lifetime durability against light emission and repeated repeated emission durability for a short time, and an inexpensive flash discharge tube. Thus, a significant improvement in the repeated light emission durability characteristics can be realized at a low cost.

  Needless to say, the use of the flash discharge tube according to the present invention is not limited to the use in the above-described strobe device. For example, an aircraft obstruction light, an aircraft or an aircraft installed in a high place such as a bridge or a high-rise building. Of course, it can be applied as a light source such as a warning light mounted on an emergency vehicle such as a police car.

  The flash discharge tube according to the present invention and the method for manufacturing the flash discharge tube comprise an envelope composed of an aluminosilicate glass tube containing almost no alkali metal component, without using a well-known relay bulb or the like, which is a countermeasure for the coefficient of thermal expansion. Because it can realize high heat resistance and high thermal shock resistance by drastically reducing the elution phenomenon of metal components, it is applied to obtain a flash discharge tube that has excellent emission lifetime durability and short-term repeated emission durability and is inexpensive. be able to.

  In addition, since the strobe device of the present invention uses the flash discharge tube as a light source, the strobe device can be applied to obtain a strobe device that can significantly improve the light emission life durability characteristics and the repeated light emission durability characteristics for a short time at a low cost. can do.

1 Flash discharge tube 2 Envelope 2a One end 2b Other end 3 Xenon gas 4 Anode bead 4a First anode bead 4b Second anode bead 5 Cathode bead 6 Electrode pin 7 Electrode pin 8 External pin 9 Sintered body 10 External pin DESCRIPTION OF SYMBOLS 11 Main body 12 Subject 13 Reflector 14 Optical member 15 Optical control means 16 Light emission operation control means

Claims (7)

A flash discharge tube in which a discharge electrode is hermetically sealed at both ends of a translucent envelope with xenon gas sealed therein, and the envelope is mainly composed of aluminosilicate. The discharge electrode is made of an aluminosilicate glass tube containing almost no alkali metal component, and the discharge electrode is made of a borosilicate glass and has a first electrode pin and an outer diameter less than the inner diameter of the aluminosilicate glass tube. A first bead formed by being directly wound and hermetically sealed, and made of borosilicate glass. The first bead is formed around the first bead so as to have an outer diameter substantially equal to the outer diameter of the aluminosilicate glass tube. An anode bead composed of a second bead formed by being wound with a length shorter than the axial length and hermetically sealed, and is attached to one end surface of the aluminosilicate glass tube end The anode is hermetically bonded to the aluminosilicate glass tube by being melt-bonded through the end face of the second bead forming the polar bead, the second electrode pin, and borosilicate glass. The aluminosilicate glass tube is composed of a cathode bead that is directly wound to have an outer diameter that is less than the inner diameter of the aluminosilicate glass tube and is hermetically sealed, and a sintered body that is fixed to the tip of the second electrode pin. By heating and melting the vicinity of the other end portion of the silicate glass tube end portion, the other end portion is brought into the substantially central portion of the side surface of the cathode bead to form a recess in the substantially central portion of the side surface of the cathode bead. A flash discharge tube comprising a silicate glass tube and a hermetically sealed cathode. The flash discharge tube according to claim 1, further comprising a transparent conductive film formed on an outer surface of the envelope and applied with a trigger voltage. 3. A flash discharge tube according to claim 1, further comprising a silicon dioxide film having a thickness of 130 to 400 nm formed by applying and baking a silanol solution on the inner surface of the envelope. A strobe device comprising the flash discharge tube according to claim 1 as a light source. A discharge electrode is hermetically sealed with xenon gas sealed at both ends of a translucent envelope made of an aluminosilicate glass tube containing aluminosilicate as a main component and almost no alkali metal component. A method of manufacturing a flash discharge tube, wherein a first bead made of borosilicate glass is directly wound around a first electrode pin so as to have an outer diameter less than the inner diameter of the aluminosilicate glass tube, and a first bead made of borosilicate glass is used. An anode for forming an anode by winding two beads around the first bead so as to have an outer diameter substantially equal to the outer diameter of the aluminosilicate glass tube with a length shorter than the axial length of the first bead. When forming a cathode bead made of borosilicate glass directly on the second electrode pin so that the outer diameter is less than the inner diameter of the aluminosilicate glass tube, A cathode forming step of forming a cathode by fixing a metal sintered body to the tip of the second electrode pin, an end face of the second bead forming the anode bead, and one end of the aluminosilicate glass tube. An anode sealing step in which the aluminosilicate glass tube and the anode are hermetically sealed by fusion bonding, the other end portion of the aluminosilicate glass tube is positioned in the vicinity of the substantially central side surface of the cathode bead, and By heating and melting only the vicinity of the other end in a state where the xenon gas is sealed inside the aluminosilicate glass tube, and by letting the other end enter into a substantially central portion of the side surface of the cathode bead so as to form a recess. A method of manufacturing a flash discharge tube comprising a cathode sealing step for hermetically sealing the aluminosilicate glass tube and the cathode. A flash discharge tube in which a pair of discharge electrodes consisting of an anode and a cathode are hermetically sealed at both ends of a light-transmitting envelope with xenon gas sealed therein, It consists of an aluminosilicate glass tube containing aluminosilicate as a main component and almost no alkali metal component. A cathode bead that is directly wound and sealed to have an outer diameter of less than, and a hermetic sealed cathode bead, and a sintered body fixed to the tip of the electrode pin, and a substantially central side surface of the cathode bead; The vicinity of the end of the aluminosilicate glass tube is locally heated and melted so that the end of the tube enters the substantially central part of the side surface of the cathode bead, and the central part of the side surface of the cathode bead Flash discharge tube, characterized in that said the aluminosilicate glass tube and hermetically sealed by forming a recess. A pair of discharge electrodes consisting of an anode and a cathode with a xenon gas sealed inside both ends of a translucent envelope made of an aluminosilicate glass tube containing aluminosilicate as a main component and containing almost no alkali metal component Is a method of manufacturing a flash discharge tube, wherein at least a cathode bead made of borosilicate glass is directly wound around an electrode pin so that the outer diameter is less than the inner diameter of the aluminosilicate glass tube, A cathode forming step of forming a cathode by fixing a metal sintered body to the tip of the electrode pin; and the other end of the aluminosilicate glass tube is positioned in the vicinity of the substantially central side of the cathode bead, and In the state where the xenon gas is sealed inside the aluminosilicate glass tube, only the vicinity of the other end is heated and melted, and the other end is connected to the cathode bead. The aluminosilicate production method of the glass tube and the flash discharge tube comprising a cathode sealing step of hermetically sealed and a cathode by causing submerge to form a recess on a side surface substantially central portion of.