JP2003263971A - Tubular bulb - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tubular bulb which has a blocking body composed mainly of a gradient functional material and not liable to break. <P>SOLUTION: The main part of the tubular bulb is composed of a nonconductive material. The tubular bulb is integrally constituted of a bulb 1 having opening sections 1b and the blocking bodies 2 composed mainly of the gradient functional material which includes third regions 2c of being conductive material-rich, second regions 2b and forth regions 2d of gradient material continuing from both ends of the third regions 2c, and first regions 2a and fifth regions 2e of being nonconductive material-rich continuing from other ends of the second regions 2b and the forth regions 2d, wherein the opening sections 1b of the bulb 1 is closed with the first regions 2a and the fifth regions 2e and equipped with the blocking bodies 2 forming first sealing portions s1 and second sealing portions s2. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bulb sealed with a closure body mainly composed of functionally graded material.

[0002]

2. Description of the Related Art For example, Japanese Unexamined Patent Publication No. 10-188897 discloses a high pressure discharge lamp in which a bulb is sealed by using a closing body made of a functionally graded material. This high-pressure discharge lamp is, as shown in FIG. 1 of the above publication,
The ends of the quartz glass arc tube, that is, the end portions of the closing portions formed at both ends of the bulb are hermetically closed by sealing the non-conductive material rich region of the closing body made of the functionally gradient material in the opening portion of the bulb. . The closing body has a cylindrical shape with a central hole, and is a mixture of silica powder and molybdenum powder, and one end of the closing portion of the arc tube is almost Si.
O ₂ 100%, the other end exposed to the outside is SiO ₂ and M
o Each has a composition of 50%, and the mixing ratio of the powders differs continuously or stepwise in the length direction. Then, the electrode mandrel is inserted through the central hole of the closing body, and airtightly fixed by metal wax on the end face of the other end exposed to the outside. (Prior Art 1) Further, as shown in FIG. 2 of the above-mentioned publication, first and second center holes are formed from both end surfaces of the closing body that reach the portions having electrical conductivity but do not penetrate, A configuration is also described in which an electrode mandrel is inserted from the first center hole and a terminal is inserted from the second center hole, respectively, and the electrode mandrel is connected to the closing body by using a metal wax in an intermediate portion of the first center hole. . (Prior Art 2) Then, Conventional Art 1
According to (2) and (2), there is an advantage that defects such as cracking of the sealing portion and foil breakage due to the oxidation of the metal foil and the entry of the halide into the sealing portion of the metal halide lamp, which are defects in the conventional foil sealing method, do not occur.

[0003]

However, in each of the prior arts 1 and 2, the bending strength between the conductive material rich region and the non-conductive material rich region of the closing body is not sufficient, and the closing body is There is a problem that it is easy to break.

An object of the present invention is to provide a tube in which a closing body mainly composed of a functionally graded material is hard to break.

[0005]

According to a first aspect of the present invention, there is provided a bulb having a main portion made of a non-conductive material and having an opening; a conductive material-rich region and a conductive material-rich region on both sides of the valve. The functionally graded material mainly includes a pair of gradient material regions having one continuous end and a pair of non-conductive material rich regions continuous with the other end of the pair of gradient material regions. And a closing body that closes the opening of the valve in a region.

In the present invention and each of the following inventions, the definitions and technical meanings of terms are as follows unless otherwise specified.

The "tube" means a structure including a valve which is hermetically sealed, and a functional portion is sealed inside the valve. In this case, the functional unit may be any function, for example, a light emitting function, a light receiving function, a sensor function, or the like. The light emitting function may be based on any operating principle, and examples thereof include a discharge lamp, an incandescent lamp, a chemiluminescent body, and a luminous body using a radioisotope. As described above, the bulb of the present invention has an extremely broad concept, but among them, the discharge lamp is suitable, and therefore the discharge lamp will be described below. "Discharge lamp" is a broad concept including various kinds of discharge lamps in which at least one electrode is sealed inside a bulb. For example, it may be either a high pressure discharge lamp or a low pressure discharge lamp.
The high-pressure discharge lamp described above has a discharge medium filled in the bulb that has a pressure of about atmospheric pressure during lighting.
It includes a discharge lamp called an ultra-high pressure discharge lamp that has a pressure higher than atmospheric pressure. The discharge generated inside the bulb may be either a metal vapor discharge or a gas discharge. Therefore, as the high pressure discharge lamp, for example, a metal halide lamp, a mercury lamp, a high pressure sodium lamp, a high pressure xenon lamp or the like is allowed. On the other hand, the low-pressure discharge lamp includes a low-pressure mercury vapor discharge lamp such as a fluorescent lamp and a germicidal lamp and a low-pressure rare gas discharge lamp such as a neon lamp, which is lit when the discharge medium is at a pressure lower than atmospheric pressure.

The main part of the bulb is made of a non-conductive material, and its opening is sealed with a closing body as described later to form an airtight discharge vessel having a functional part sealed therein. , The functional part is housed inside. In addition, the bulb has a substantial transparency to a desired radiation in order to guide the radiation generated inside the bulb to the outside or to introduce the radiation from the outside into the inside of the bulb. There is. However, the radiation transparency of the bulb does not have to be the entire extent of the bulb, and it is sufficient that the desired portion is transparent.

The opening portion of the valve is formed of a non-conductive material as a part of the main portion and can be arranged at a desired position of the valve, and its number, size and shape are specified. The configuration is not limited to the above. For example, the openings may be provided at both ends and one end of the valve.

Further, the bulb is not limited to a particular material as long as it is fire resistant, permeable to radiation and processable. The “fire resistance” may be sufficient to withstand the operating temperature of the tube. In addition, the transparency to the radiation may be such that at least a main part of the bulb that guides the radiation to the outside is transparent to the radiation. Further, "workability" means that it is possible to cope with the processing when the opening of the valve is airtightly closed by the closing body. As the constituent material of the valve, for example, glass and translucent ceramics can be widely used. The term "glass" includes quartz glass, hard glass, soft glass, crystallized glass and diamond. The "translucent ceramics" means translucent polycrystalline aluminum oxide, single crystal aluminum oxide (sapphire), yttrium-aluminum-gallium oxide (YAG), yttrium oxide (YO), aluminum nitride. It is meant to include such things as.

The closing body is for closing the opening of the valve in an airtight manner, and is mainly composed of a functionally gradient material.
At least both sides of the conductive material rich region are integrally provided with a pair of non-conductive material rich regions via inclined material regions.

The conductive material rich region is a region where the content ratio of the conductive material is 30% by mass or more, preferably 50% by mass or more, and a portion where the content ratio of the conductive material in the gradient material region is relatively large. It can be configured by. But,
If necessary, a separately prepared member can be sintered together with the gradient material region and integrally to obtain a functionally gradient material in which the conductive material rich region and the gradient material region are integrated. You can It should be noted that the separate body may be any of a pre-sintered body containing a conductive material and a non-conductive material, a main sintered body, and a metal solid. As the conductive material, one or more kinds of conductive metals such as W, Mo, Ta, Pt and V, or a conductive metal oxide can be used.

The gradient material region is formed between the conductive material rich region and a non-conductive material rich region described later.
It intervenes in the state integrated with these. Then, the conductive material and the non-conductive material are mixed, and the mixing ratio thereof is continuously or stepwise changed from at least one end to the other end. Further, the portion where the mixing ratio of the conductive material is large is continuous to the conductive material rich region. As the conductive material, one or more kinds of conductive metals such as W, Mo, Ta, Pt and V, or a conductive metal oxide can be used. Further, it is preferable to use the same kind of material as the conductive material in the gradient material region in terms of the coefficient of thermal expansion as the conductive material in the conductive material rich region, but if necessary, a different type of material may be used. Good. The non-conductive material is not particularly limited.

In the non-conductive material rich region, at least the surface region facing the opening of the valve is rich in the non-conductive material. Therefore, the inside may be in a state of being rich in non-conductive material or in a state of being rich in conductive material, like the surface region.

The non-conductive material rich region may be composed of a portion having a large mixing ratio of the non-conductive material in the gradient material region, or may be formed separately. In the latter case, the non-conductive material rich region prepared as a separate body can be sintered and integrated together with the functionally graded region as a part of the functionally graded material. It should be noted that, when integrated, the non-conductive material is melted and fused to the gradient material region, or the powder of the non-conductive material is interposed and fused by melting the powder, or the low melting point glass is interposed. It can be fused.

Further, the constituent material of the non-conductive material rich region is not particularly limited, but if a material similar to the material forming the opening of the valve is used, the difference in coefficient of thermal expansion becomes small. Therefore, it is preferable. However, different materials may be used if desired.

Furthermore, the non-conductive material rich region is
The non-conductive material may be about 80 to 100 mass%.
However, it is preferable to obtain 90-
It is in the range of 100% by mass.

Next, the structure for closing the opening of the valve with the closing member will be described. According to the present invention, the closing body includes a pair of non-conductive material rich regions that are separated by a conductive material rich region and a pair of gradient material regions, and the valve is formed by the pair of non-conductive material rich regions. It has a characteristic configuration of closing the opening of the. And, suitable means can be used for sealing. For example, the non-conductive material rich region and the opening of the bulb can be directly melted, or can be sealed by using frit glass or metal wax. In addition, a powder of the same material as the non-conductive material in the non-conductive material rich area, for example, SiO ₂ powder or Al ₂ O ₃ powder, is interposed between the non-conductive material rich area and the opening of the valve for heating. It can also be sealed by melting. In any case, it is necessary to perform sealing so that the heat during the operation of the tube does not hinder the sealing. It should be noted that the conductive material rich region and the graded material region located between the pair of non-conductive material rich regions must be prevented from being sealed in the valve opening.

Means for externally supplying electric power to the functional portion of the bulb sealed inside the valve can be performed by using known means, and is not particularly limited.
For example, it is possible to form an insertion hole that penetrates the closing body from the outside to the inside of the valve, insert the introduction body airtightly into the insertion hole, and supply power via the introduction body. In addition, the first insertion hole reaching from the end surface of the one non-conductive material rich region located outside the closing body to the conductive material rich region is formed, and the other end surface of the other non-conductive material rich region is made conductive. A second insertion hole that reaches the material rich region but does not communicate with the first insertion hole is formed, an external introduction body is inserted into the first insertion hole, and an internal introduction body is inserted into the second insertion hole. For example, it is possible to supply power to the functional unit in the valve via the external introduction body, the conductive material rich region and the internal introduction body. The internal introduction body may also serve as a part of the functional portion, for example, an electrode.

The functionally gradient material can be manufactured by known means. For example, a slip casting method, a flock casting method, a pressing method, and a partial material discharging method (tentative name) can be used. The slip cast method is
It is a manufacturing method for obtaining a functionally gradient material by casting a slurry containing a conductive material and a non-conductive material into a mold having water absorbency such as gypsum, and drying and sintering the molded body obtained by gradient precipitation. .

The flock casting method is a method in which the composition ratio is continuously changed by utilizing the difference in specific gravity in the process of molding a slurry containing a solvent, a coagulant, a conductive material and a non-conductive material in a hot water bath. is there.

In the pressing method, a plurality of kinds of mixed powders having different mixing ratios of the conductive material and the non-conductive material are prepared and wet mixed with a solvent to which an organic binder is added for each kind of mixed powder. In the manufacturing method, the granulated and dried material is filled in layers in the mold in order of mixing ratio, pressed to obtain a molded body, the organic binder is volatilized by temporary sintering, and the functionally graded material is obtained by main sintering. is there.

In the partial material discharge method, first, molybdenum which is a conductive material and SiO _{2 which} is a non-conductive material are uniformly mixed as a material before the discharge treatment of a desired material component, or a mixing ratio of these is inclined. And prepare the distributed sintered body. Then, the sintered body is heated in an oxidizing atmosphere. Since molybdenum in the sintered body is oxidized and sublimated, molybdenum in the surface layer is reduced according to the depth. As a result, a functionally gradient material having a mixed ratio inclined in the depth direction of the sintered body can be obtained.

Thus, in the present invention, since the pair of non-conductive material rich regions, which are separated by sandwiching the conductive material rich region and the inclined material region of the closing body, seal the opening of the valve, the conductivity is improved. Bending strength between the material-rich region and the non-conductive material-rich region is increased. As a result, the closing body is less likely to break.

Further, since the sealing is carried out at two places separated from each other in the tube axis direction, good sealing can be obtained.

According to a second aspect of the present invention, in the first aspect of the present invention, the conductive material rich region and the non-conductive material rich region are formed as part of the gradient material region. .

The present invention defines a configuration in which the conductive material rich region, the graded material region and the non-conductive material rich region are present in one graded material region. Therefore,
The functionally graded material region of the present invention constitutes a functionally graded material having three above-mentioned regions by itself. In order to form such a functionally graded material, for example, two unsintered bodies of a unidirectionally graded material region are formed, and the conductive material rich regions are pressed against each other and sintered to form an integrated body. A closed occlusion body can be obtained.

Thus, in the present invention, by having the above-mentioned constitution, the manufacture of the closing body becomes relatively easy.

According to a third aspect of the present invention, in the bulb according to the first or second aspect, the bulb is mainly made of quartz glass; and the closing body is mainly made of SiO ₂ as a non-conductive material. The conductive material is mainly composed of Mo.

The present invention defines suitable materials of construction for the valves and closures. That is, since the main part of the bulb is made of quartz glass, the problem of sealing with a metal foil in the conventional sealing of quartz glass is solved. In addition, since the conductive material is mainly composed of Mo in the blocker, the non-conductive material is mainly composed of SiO ₂ and the thermal expansion coefficients of the both are relatively close to each other. Less cracks. Moreover, since the non-conductive material and the material of the bulb are the same, excellent sealing can be performed.

Thus, according to the present invention, it is possible to obtain a tube having an excellent sealing portion which does not cause a problem as in the case of the sealing portion using the metal foil in the conventional quartz glass bulb. it can.

A tube according to a fourth aspect of the present invention is the tube according to any one of the first to third aspects, wherein the electrode is supported by the closing body, and the discharge medium is sealed inside the bulb.
It is characterized in that it is a discharge lamp equipped with.

The electrode can be supported by embedding the base end of the electrode in the closing body or by integrally disposing the electrode at the tip of the closing body. The electrodes may be cold cathodes or hot cathodes. If necessary, an electron emissive substance can be attached to the electrode.

The distance between the electrodes may be set to either a short arc type or a long arc type. Further, while one electrode is supported by the closing body and sealed inside the valve, the other electrode is disposed on the outer surface of the valve,
It can also be configured to perform a dielectric barrier discharge. Furthermore, if the electrode is made of tungsten, it is preferable because it has excellent heat resistance and electron emission. However, if necessary, molybdenum, nickel, titanium or the like may be used.

The discharge medium may be a suitable one depending on the type and structure of the discharge lamp. INDUSTRIAL APPLICABILITY The present invention is suitable for a metal halide lamp in which a halide of a luminescent metal is enclosed because it is not sealed with a metal foil.

Thus, in the present invention, by having the above-mentioned structure, it is possible to obtain a bulb which is a discharge lamp that is well sealed.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a metal halide lamp as an embodiment of the discharge lamp of the present invention.
Is a front view, and FIG. 2 is an enlarged cross-sectional view of the closing body. In each figure, 1 is a valve, 2 is a pair of closures, 3 is a pair of electrodes, 4 is a pair of external lead wires.

The bulb 1 is made of quartz glass and has a surrounding portion 1a and an opening 1b. The surrounding portion 1a has, for example, a spheroidal shape, has a hollow interior, and has a discharge space 1a.
form c. The maximum inner diameter of the surrounding portion 1a as one example is about 6 mm. A pair of openings 1b are formed at both ends in the tube axis direction of the surrounding portion 1a, communicate with the discharge space 1c, and have an inner diameter slightly smaller than the outer diameter of the closing body 2 in the state before sealing. It has a large tubular shape.

As shown in the enlarged view of FIG.
It has a columnar shape, and has five regions in the length direction, that is, a first region 2a and a second region 2b from the distal end toward the proximal end.
Third region 2c, fourth region 2d and fifth region 2e
Are integrally formed.

The first area 2a and the fifth area 2e are
Both are non-conductive material-rich regions and are separated from each other with the second to fourth regions 2b to 2d described later interposed therebetween. In addition, the first region 2a and the fifth region 2e are S
iO ₂ is 100% by mass. Then, as will be described later, a pair of sealing portions s1 and s2, which are spaced apart from each other, are formed in cooperation with the opening 1b of the valve 1.

The second area 2b and the fourth area 2d are
Both are gradient material regions, and are separated from each other with a third region 2c described later interposed therebetween. In the gradient material region, the conductive material is made of Mo, the non-conductive material is made of SiO ₂ , and the content ratio of the conductive material is 20% by mass or less at one end portion adjacent to the first and fifth regions. Although it is relatively small, the ratio of the conductive material is gradually increased, and the content ratio of the conductive material is relatively large at the other end portion adjacent to the third region, for example, 40% by mass or more. Has become.

The third region 2c is a conductive material rich region, and the conductive material is 50% by mass or more. In addition, as one example, the closing body 2 has a diameter of 2 mm and a length of 20 mm.

Thus, the closing body 2 is made of a functionally graded material in which the first region 2a to the fifth region 2e are integrated. Further, a first insertion hole 2f reaching from the end face of the fifth region 2e to the third region 2c is formed along the central axis. Furthermore, from the first area 2a to the third area
A second insertion hole 2g reaching the area 2c is formed along the central axis. The first and second insertion holes 2
f and 2g are not in communication.

The electrode 3 includes an electrode shaft portion 3a and a coil portion 3
b. The electrode shaft portion 3a is made of a tungsten rod, and the base end thereof is inserted into the second insertion hole 2g to form a third rod.
Is connected to the conductive rich region of the region 2c. The coil portion 3b is made of a tungsten wire and is wound around the tip of the electrode shaft portion 3a.

The external lead-in wire 4 is made of a molybdenum rod,
The tip is inserted into the first insertion hole 2f and the third region 2c
Connected to. In addition, the base end side of the external lead-in wire 4 is led out from the base end of the closing body 2.

Thus, the closing body 2, the electrode 3 and the external lead-in wire 4 constitute an electrode mount M, and the opening 2b of the valve 1 is closed by the closing body 2. That is, the closure body 2
Is inserted into the opening 1b of the valve 1 from the first region 2a at the tip to the planned sealing portion of the fifth region 2e, and the first region 2a and the fifth region which are the non-conductive material rich region and the fifth region 2e are inserted. Region 2e and the opening 2b are heated and melted by an argon plasma burner, an oxygen-hydrogen burner or the like to hermetically seal them to form a first sealing part s1 and a second sealing part s2, respectively. is doing. As a result, both ends of the surrounding portion 1a of the bulb 1 are sealed so that the discharge space 1c is hermetically sealed inside.
Are formed.

Further, a pair of electrodes 3 and 3 whose base ends are supported by the pair of closing bodies 2 and 2 project from both ends of the discharge space 1c and face each other at a distance. The distance between the electrodes is 1.4 mm as an example. Prior to the above-mentioned sealing, the discharge space 1c is filled with, for example, mercury, Sc and Na iodides, and argon as an example of the discharge medium to form a metal halide lamp. The rated lamp power is 100 W and the lamp voltage is 83V.

The discharge lamp can be turned on by connecting the pair of external introduction lines 4 and 4 between the output terminals of the lighting circuit.

[0050]

According to each of the first to fourth aspects of the invention, the conductive material rich region, the pair of gradient material regions whose one ends are continuous to both sides of the conductive material rich region, and the other end of the pair of gradient material regions. A functionally-graded material including a pair of non-conductive material rich regions that are continuous with each other is integrally formed, and a pair of non-conductive material rich regions that closes the valve opening. Thus, it is possible to provide a tube in which the closing body is hard to break and which is well sealed.

According to the second aspect of the present invention, the conductive material rich region and the non-conductive material rich region are formed as a part of the gradient material region, so that the structure of the closing body is relatively simple. A sphere can be provided.

According to the invention of claim 3, since the main part of the bulb is made of quartz glass, the non-conductive material of the closing body is mainly SiO ₂ , and the conductive material is mainly Mo. It is possible to provide a tube provided with a sealing portion that can achieve excellent sealing without problems such as in a sealing portion using a metal foil.

According to the invention of claim 4, it is possible to provide a bulb comprising a discharge lamp provided with an electrode supported by the closing body and a discharge medium sealed in the bulb.

[Brief description of drawings]

FIG. 1 is a front view showing a metal halide lamp as an embodiment of a discharge lamp of the present invention.

FIG. 2 is an enlarged sectional view of the closing body.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bulb, 1a ... Enclosing part, 1b ... Opening part, 1c ... Discharge space, 2 ... Closing body, 2a ... 1st area, 2b ... 2nd area, 2c ... 3rd area, 2d ... 4th Area, 2e ... Fifth
Area, 3 ... Electrode, 3a ... Electrode shaft, 3b ... Coil, M ...
Electrode mount, s1 ... First sealing portion, s2 ... Second sealing portion, 4 ... External lead-in wire

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshihiko Ishigami             4-3-1, Higashishinagawa, Shinagawa-ku, Tokyo             Itec Co., Ltd. (72) Inventor Kozo Uemura             4-3-1, Higashishinagawa, Shinagawa-ku, Tokyo             Itec Co., Ltd. (72) Inventor Nobuhiro Tamura             4-3-1, Higashishinagawa, Shinagawa-ku, Tokyo             Itec Co., Ltd. (72) Inventor Takuya Honma             4-3-1, Higashishinagawa, Shinagawa-ku, Tokyo             Itec Co., Ltd. (72) Inventor Ikue Kanabe             1 Hariso at 5-2 Asahi-cho, Imabari-shi, Ehime             Within Toshiba Lighting Co., Ltd. F term (reference) 5C043 AA14 CC01 CC04 CD01 DD03                       EB15

Claims (4)

[Claims] 1. A valve having a main part made of a non-conductive material and having an opening; a conductive material rich region; a pair of gradient material regions having one end continuous to both sides of the conductive material rich region;
And a functionally gradient material including a pair of non-conductive material rich regions that are continuous with the other ends of the pair of gradient material regions, and is integrally formed, and the pair of non-conductive material rich regions closes the valve opening. A bulb comprising: a closed occlusion body; 2. The tube according to claim 1, wherein the conductive material rich region and the non-conductive material rich region are formed as a part of the gradient material region. 3. The bulb is mainly made of quartz glass;
The non-conductive material of the blocker is mainly composed of SiO ₂ ,
3. The tube according to claim 1, wherein the conductive material is mainly Mo. 4. A discharge lamp comprising: an electrode supported by a closing body; and a discharge medium sealed inside a bulb. Tube.