WO2012046597A1

WO2012046597A1 - Method for producing ceramic tube and ceramic tube

Info

Publication number: WO2012046597A1
Application number: PCT/JP2011/072112
Authority: WO
Inventors: 宮澤杉夫; 渡邊敬一郎; 大橋玄章
Original assignee: 日本碍子株式会社
Priority date: 2010-10-08
Filing date: 2011-09-27
Publication date: 2012-04-12
Also published as: EP2626882A4; EP2626882A1; JPWO2012046597A1; CN103155087A

Abstract

This method for producing a ceramic tube produces a single ceramic tube for a high-brightness discharge lamp by joining a plurality of ceramic compacts, and has: a compact-producing step (step S1) for producing a plurality of ceramic compacts including at least one ceramic compact having a groove on the joining surface; and a compact-joining step (step S2) for joining the joining surfaces of the plurality of ceramic compacts to each other. The method for producing a ceramic tube produces a ceramic tube having a hole formed by means of the groove.

Description

Manufacturing method of ceramic tube and ceramic tube

The present invention relates to a method for producing a ceramic tube used for a high-intensity discharge lamp such as a high-pressure sodium lamp or a metal halide lamp, and a ceramic tube.

A ceramic metal halide lamp ionizes a metal halide with a pair of electrodes inserted in a ceramic tube for a high-intensity discharge lamp, thereby obtaining discharge light emission.

This type of ceramic tube has a pair of tubules formed so that each axis is positioned so as to face the light emitting portion. Each thin tube is provided with an electrode insertion hole, and an electrode is inserted through these electrode insertion holes. Various types of ceramic tubes are disclosed, such as those produced by assembling a plurality of members, those produced integrally as a single member, and those produced by joining two members (for example, JP 63-143738, JP 5-334962, JP 7-21990, JP 8-55606, JP 2010-514125, JP 2010-514127, US (See Japanese Patent Application Publication No. 2006/0001346, JP-T 2009-530127, JP-A 2008-44344).

For example, of the two narrow tubes (pores) provided in the ceramic tube, the electrode is inserted into one electrode insertion hole and sealed with frit glass or the like, and then the luminescent substance is introduced through the remaining electrode insertion hole. After introducing into the luminous container, an electrode is inserted into the other electrode insertion hole and sealed with frit glass or the like to assemble the luminous tube. As another structure, in addition to the above-described two capillaries in the ceramic tube, the third capillaries for introducing the luminescent substance into the luminescent container in order to introduce the luminescent substance after sealing the electrode or A structure is also known in which pores are provided separately from the thin tubes for inserting electrodes.

Specifically, Japanese Patent Application Laid-Open No. 63-143738 discloses that both ends of an arc tube bulb made of translucent ceramic are sealed by solid-phase bonding with a closed body made of a conductive cermet that supports the electrodes. An example of a ceramic discharge lamp in which a small hole used for exhaust in a tube and for supplying an enclosure is provided in an arc tube bulb is disclosed. This small hole is closed by welding a ceramic plug.

Japanese Patent Laid-Open No. 5-334962 discloses that closed bodies are respectively attached to cylindrical openings at both ends of a translucent valve made of polycrystalline alumina, and holes through which electrodes pass respectively are provided at the central positions of the closed bodies. An example is disclosed in which an opening for introducing a luminescent substance into a translucent bulb is formed at a position that is formed and decentered from the center of one closing member.

Japanese Patent Application Laid-Open No. 7-21990 discloses an example in which pin-shaped current conductors having a diameter of 300 μm are inserted into both ends of a discharge tube, and plugs at both ends are directly joined to both ends by sintering. 3 and 4 show an example in which a filling hole having a diameter of 1 mm or more for introducing a luminescent material into the discharge tube is formed in the wall portion of the discharge tube or the second plug near the second end portion. .

In JP-A-8-55606, a small-diameter tube whose lower end is closed downward from the center portion of the funnel-shaped portion of the arc tube is integrally suspended to provide a lower portion in the small-diameter tube (during lighting). An example is disclosed in which the liquid metal halide that remains in the arc tube without being evaporated is stored in the coldest part: the coldest part). In particular, one of the openings provided in the flange-shaped intermediate part that is removed from the coldest part is used as an inlet for sealing the metal halide and mercury in the arc tube, and the small-diameter pipe is used as the inlet pipe. There is a description that it can also be used.

In Japanese Translation of PCT International Application No. 2010-514125, one end of the discharge vessel and the wall of the tube are made as an integral part of the discharge vessel, and the other end of the discharge vessel is sealed with a ceramic end plug. A ceramic burner is disclosed. In particular, a tube is provided on the ceramic wall of the discharge vessel for introducing the ionized filler into the discharge vessel during the production of the ceramic burner and which projects outwardly from the ceramic wall of the discharge vessel. Examples have been disclosed. The tube is hermetically sealed.

In Japanese Translation of PCT International Publication No. 2010-514127, the discharge vessel is made, for example, substantially spherical or substantially elliptical by two different parts (separated by a broken line in FIG. 2A of the publication) Only a portion of one discharge vessel is provided with a tube for introducing an ionized filler into the discharge vessel during the production of the ceramic burner and protruding outward from the ceramic wall of the discharge vessel Examples have been disclosed. The tube is hermetically sealed.

U.S. Patent Application Publication No. 2006/0001346 has a cylindrical portion and end members respectively coupled to both ends of the cylindrical portion, and inward of the cylindrical portion at the center of each end member. An example in which an electrode extending in the direction is provided is disclosed, and in particular, one end member is provided with an introduction hole penetrating from the outer surface of the end member to the inner surface (the surface facing the inside of the tube portion). Yes. The introduction of the metal halide or the like into the cylindrical portion is performed through the introduction hole, and then the introduction hole is sealed with a plug member.

In addition, conventionally, a slurry can be applied to the joint surfaces of a plurality of inorganic powder compacts, and a plurality of compacts can be butted together to be integrated and sintered, whereby a strong joint sintered body can be obtained. There are known methods (for example, JP-T-2009-530127) and structures capable of obtaining a bonded inorganic powder molded body while suppressing or avoiding deformation of the bonded portion and increase in surface roughness (for example, JP, 2008-44344, A).

That is, JP-T-2009-530127 discloses a method for producing a sintered body suitable for use in an arc tube of a discharge lamp, containing an inorganic powder, an organic dispersion medium having a reactive functional group, and a gelling agent. And a step of obtaining a first inorganic powder molded body and a second inorganic powder molded body solidified by a chemical reaction between an organic dispersion medium and a gelling agent, and a powder component on a bonding surface of the first inorganic powder molded body And a step of applying a slurry containing the organic dispersion medium and an inorganic powder molded body in contact with the slurry interposed therebetween to obtain an integral joined body, and sintering and sintering the joined body. Obtaining a ligation.

Japanese Patent Application Laid-Open No. 2008-44344 discloses a sintered body suitable for use in an arc tube of a discharge lamp, and a sintered body of a joined body of two or more inorganic powder molded bodies is used as two or more of the joined bodies. A first component corresponding to the inorganic powder molded body and a second component corresponding to a bonded portion in the bonded body, and any of the following features (a) and (b) Or have both.

(A) The second component has a surface roughness equal to or less than that of the first component.

(B) The second constituent part has a light transmission greater than that of the first constituent part in the vicinity of the width center thereof.

By the way, Japanese Patent Laid-Open Nos. 63-143738, 5-334962, 7-21990, 8-55606, 2010-514125, 2010-514127. In US Patent Application Publication No. 2006/0001346, when a thin tube or pore for introducing a luminescent material is formed in this type of ceramic tube, either the side surface of the pre-formed ceramic tube or one of the ceramic tubes is used. A method is employed in which pores are processed in the plugs sealed at the ends of the pipes, or a method of assembling capillaries in the pores. However, in this case, there is a problem that a lot of man-hours are required for drilling and assembly. There is.

Of course, by adopting methods such as casting, injection molding, and gel casting, it is possible to mold a thin tube at the same time, but since the molded body does not have a simple axisymmetric shape, the structure of the mold becomes complicated, There is a problem that the manufacturing cost of the mold increases.

In the structures described in Japanese Patent Laid-Open Nos. 5-334962 and 7-21990, the pores are located at or near the coldest portion of the arc tube. When the arc tube is turned on, all of the metal halide does not evaporate, and a part of it becomes liquid and accumulates in the coldest part in the arc tube. As a result, the sealing portion (seal) of the pores may corrode.

When a thin tube is provided in a ceramic tube, especially when the axial direction of the thin tube is set perpendicular to the tangent to the outer diameter of the ceramic tube, the thin tube is very thin and easily breaks. In addition, since it is away from the light emitting part, it is likely to be the coldest point and is easily corroded.

The present invention has been made in consideration of such problems, and it is not necessary to perform hole processing or additional processing for providing a thin tube, and it is possible to provide pores or thin tubes in a ceramic tube with a simple process. Another object of the present invention is to provide a method for producing a ceramic tube for a high-intensity discharge lamp, which can reduce production costs and improve productivity.

Another object of the present invention is to prevent the thin tube from being damaged and to prevent the thin tube from being arranged at the coldest point, thereby improving yield and reliability. An object of the present invention is to provide a ceramic tube for a high-intensity discharge lamp.

[1] A method of manufacturing a ceramic tube according to the first aspect of the present invention is a method of manufacturing a ceramic tube in which a plurality of ceramic molded bodies are bonded to produce one ceramic tube for a high-intensity discharge lamp. A molded body producing step for producing a plurality of ceramic molded bodies including at least one ceramic molded body having a molded body joining step for joining the joining surfaces of the plurality of ceramic molded bodies. A ceramic tube in which a through hole is formed is produced.

[2] In the first aspect of the present invention, the molded body manufacturing step includes manufacturing one first ceramic molded body having a groove on the joint surface and one second ceramic molded body having no groove on the joint surface. The molded body joining step is characterized by joining one first ceramic molded body and one second ceramic molded body.

[3] In the first aspect of the present invention, the molded body producing step produces two first ceramic molded bodies having grooves on the joining surfaces, and the molded body joining step comprises two first ceramic molded bodies. In joining, the grooves formed on the joining surfaces of the first ceramic molded body are joined together and joined.

[4] A method for manufacturing a ceramic tube according to the second aspect of the present invention is a method for manufacturing a ceramic tube in which a plurality of ceramic molded bodies are bonded to produce a ceramic tube for a high-intensity discharge lamp. A plurality of ceramic molded bodies including at least one ceramic molded body having first protrusions constituting a portion and having through-grooves formed continuously from the end portion of the first protrusion to the inside on the joint surface And forming a ceramic tube in which a through hole is formed by the through groove. The forming body manufacturing step and the forming body joining step of joining the joint surfaces of the plurality of ceramic molded bodies to each other. .

[5] In the second aspect of the present invention, in the molded body manufacturing step, one third ceramic molded body having the first protrusion and a part of the joining surface are formed, and no through groove is formed. The molded body production step for producing at least one fourth ceramic molded body having a second projection, and the molded body joining step are performed such that the first projection and the second projection are respectively aligned with the joining surface. The third ceramic molded body and the fourth ceramic molded body are joined together.

[6] In the second aspect of the present invention, the molded body manufacturing step includes the molded body manufacturing process for manufacturing at least two third ceramic molded bodies having the first protrusions, and the molded body joining step includes the first molded body manufacturing process. The third ceramic molded body is bonded so that the protrusions are aligned with the bonding surfaces.

[7] In the second aspect of the present invention, when the intersection of the outer periphery of the joint surface having the first protrusion and the axis of the through groove in the first protrusion is the base point of the first protrusion, the joint surface The angle formed by the tangential direction at the base point and the axis of the through groove on the outer periphery is 30 ° to 60 °.

[8] In the second aspect of the present invention, the joint surface of the ceramic molded body is parallel to a surface orthogonal to the axial direction.

[9] A ceramic tube according to a third aspect of the present invention is formed by joining a plurality of ceramic molded bodies, and is provided with a light emitting portion that emits light inside, and on both sides of the light emitting portion, and each electrode is introduced and sealed. In a ceramic tube for a high-intensity discharge lamp integrally having an electrode introduction part for stopping, a through hole for introducing a luminescent substance into the light emission part is provided in the light emission part separately from the electrode introduction part. The protrusion is provided so that the axis of the protrusion is directed to the axis of the ceramic tube, and the angle formed by the axis of the protrusion and the axis of the ceramic tube is 90 °; The protrusion amount of the protrusion is in a range of 1/20 to 10/20 of the maximum diameter of the light emitting part.

[10] The ceramic tube according to the fourth aspect of the present invention is configured by joining a plurality of ceramic molded bodies, and is provided with a light emitting portion that emits light inside and on both sides of the light emitting portion, and each electrode is inserted therethrough. In a ceramic tube for a high-intensity discharge lamp integrally having an electrode introduction portion for providing a light-emitting substance, a through-hole for introducing a luminescent substance is provided in the light-emitting portion, separately from the electrode introduction portion. When the relationship between the contour line and the contour line obtained by cutting the outer surface of the light-emitting portion by a surface including the axis line of the projection and the axis line is seen at the intersection of the contour line and the axis line in the contour line The angle between the tangential direction and the axis is 30 ° to 60 °.

As described above, according to the method for manufacturing a ceramic tube according to the present invention, there is no need to perform hole processing or additional processing for providing a thin tube, and it is possible to provide pores or thin tubes in the ceramic tube in a simple process. Therefore, the manufacturing cost can be reduced and the productivity can be improved.

In addition, the ceramic tube according to the present invention can prevent the thin tube from being damaged and can avoid the thin tube from being disposed at the coldest point, thereby improving the yield and the reliability. be able to.

It is a process block diagram showing the 1st manufacturing method. It is a disassembled perspective view which shows the example of a combination of a 1st ceramic molded object and a 2nd ceramic molded object. FIG. 3A is a sectional view showing the first casting mold with a part omitted, and FIG. 3B is a sectional view showing the second casting mold with a part omitted. FIG. 4A is a cross-sectional view showing the first joined body, and FIG. 4B is a perspective view showing the first ceramic tube. It is a process block diagram which shows the conventional manufacturing method for producing the ceramic tube which has a through-hole. FIG. 6A is a cross-sectional view showing another example of the first joined body, and FIG. 6B is a perspective view showing another example of the first ceramic tube. It is a process block diagram showing the 2nd manufacturing method. It is a disassembled perspective view which shows the example of a combination of a pair of 1st ceramic molded object. FIG. 9A is a cross-sectional view showing the second joined body, and FIG. 9B is a perspective view showing the second ceramic tube. It is a process block diagram showing the 3rd manufacturing method. It is a disassembled perspective view which shows the example of a combination of a 3rd ceramic molded object and a 4th ceramic molded object. 12A is a cross-sectional view showing the third casting mold with a part thereof omitted, and FIG. 12B is a cross-sectional view showing a part of the fourth casting mold with a part omitted. It is a disassembled perspective view which shows the other example of a combination of a 3rd ceramic molded body and a 4th ceramic molded body. FIG. 14 is a diagram for explaining a protruding direction of the first protrusion and the second protrusion in the combination example of FIG. 13. FIG. 15A is a cross-sectional view showing a third joined body, and FIG. 15B is a perspective view showing a third ceramic tube based on the combination example of FIG. FIG. 16A is a perspective view showing a third ceramic tube based on the combination example of FIG. 13, and FIG. 16B is a diagram for explaining a protruding direction of a cylindrical protrusion. It is a process block diagram which shows the conventional manufacturing method for producing the ceramic tube which has a cylindrical protrusion. 18A is a diagram for explaining the protrusion amount of the cylindrical protrusion in the third ceramic tube shown in FIG. 15B, and FIG. 18B shows the protrusion amount of the cylindrical protrusion in the third ceramic tube shown in FIG. 16A. It is a figure for demonstrating. It is a process block diagram showing the 4th manufacturing method. It is a disassembled perspective view which shows the example of a combination of two 3rd ceramic molded bodies. It is a disassembled perspective view which shows the other example of the combination example of two 3rd ceramic molded bodies. 22A is a cross-sectional view showing a fourth joined body, and FIG. 22B is a perspective view showing a third ceramic tube based on the combination example of FIG. It is a perspective view which shows the 3rd ceramic tube based on the example of a combination of FIG. FIG. 3 is a diagram showing a pattern of screen plate making used in Example 1. 5 is a diagram showing a pattern of screen plate making used in Example 2. FIG.

Hereinafter, a method for manufacturing a ceramic tube and an embodiment of the ceramic tube according to the present invention will be described with reference to FIGS. In the present specification, “˜” in the numerical range is used as a meaning including numerical values described before and after the numerical value as a lower limit value and an upper limit value.

In the following embodiment, it is assumed that one ceramic tube is manufactured. Of course, the present invention can also be applied to the production of a large number of ceramic tubes.

Further, the ceramic tube is preferably used as an arc tube of a discharge lamp. The high pressure discharge lamp can be applied to various lighting devices such as road lighting, store lighting, automobile headlamps, and liquid crystal projectors. The arc tube includes an arc tube for a metal halide lamp and an arc tube for a high pressure sodium lamp.

The method of manufacturing a ceramic tube according to the first embodiment includes a molded body manufacturing step of manufacturing a plurality of ceramic molded bodies including at least one ceramic molded body having a groove on a joint surface, and each of the plurality of ceramic molded bodies. And forming a ceramic tube having a hole formed by a groove.

Several specific examples of the method for manufacturing a ceramic tube according to the first embodiment will be described with reference to FIGS.

First, a manufacturing method according to a first specific example (hereinafter referred to as a first manufacturing method) includes a first ceramic molded body 10A and a second ceramic molded body 10B, as shown in FIG. Is made. In the first ceramic molded body 10A, a groove 14 is formed on the joint surface 12a. The groove 14 is not formed on the joint surface 12b of the second ceramic molded body 10B.

Specifically, in step S1a, a ceramic powder, a dispersion medium, a gelling agent, and the like are mixed to prepare a gel casting slurry (referred to as a forming slurry). In step S1b, as shown in FIGS. 3A and 3B, the molding slurry 16 is fed into the first casting mold 18A for the first ceramic molded body 10A (see FIG. 3A) and the second for the second ceramic molded body 10B. After casting into a casting mold 18B (see FIG. 3B), it solidifies. In the first casting mold 18A, a projection 20 having a shape obtained by inverting the groove 14 is formed at a portion where the joining surface 12a is formed. Thereafter, in step S1c, the first casting mold 18A and the second casting mold 18B are released to obtain the first ceramic molded body 10A and the second ceramic molded body 10B as shown in FIG.

Both the first ceramic molded body 10 </ b> A and the second ceramic molded body 10 </ b> B are formed in a cylindrical shape having a hollow portion 22. More specifically, the first ceramic tube 24A (see FIG. 4B), which is a finished product, has a similar shape in which the first ceramic tube 24A is separated into two at the center in the longitudinal direction of the axis m1, and includes a cylindrical portion 26 and a curved portion 28 (a bowl shape). ) Are integrally formed. That is, the shape of the first bonded body 30A (see FIG. 4A) obtained by bonding the first ceramic molded body 10A and the second ceramic molded body 10B, and the first obtained by firing the first bonded body 30A. The shape of the ceramic tube 24A is similar, and the first ceramic tube 24A has a shape obtained by reducing the first joined body 30A.

The joining

surfaces

12a and 12b of the first ceramic molded body 10A and the second ceramic molded body 10B are located on the end surfaces of the curved portions 28, and are in the axial direction of the first ceramic molded body 10A and the second ceramic molded body 10B. Parallel to the orthogonal plane. One groove 14 is formed on the joint surface 12a of the first ceramic molded body 10A. The groove 14 has a semi-cylindrical shape, a prism shape, or a combination shape of a prism and a semi-cylindrical shape, and its axis n1 is directed to the axis m2 of the first ceramic molded body 10A, and an angle formed between the axis n1 and the axis m2 is set. It is 90 °. The length along the axis n1 of the groove 14 is the same as the thickness of the curved portion 28 of the first ceramic molded body 10A, and the length (width) orthogonal to the axis n1 of the groove 14 is inserted in a solid state. Therefore, the diameter of the inscribed circle is set to φ0.25 mm to φ0.9 mm. Although not shown, the outer peripheral portion and the inner peripheral portion of each

joint surface

12a and 12b of the first ceramic molded body 10A and the second ceramic molded body 10B are chamfered (for example, R surface, C surface). Also good.

In step S2 of FIG. 1, the first ceramic molded body 10A and the second ceramic molded body 10B are bonded to produce a first bonded body 30A.

Specifically, in step S2a, ceramic powder, a solvent, a binder, and the like are mixed to prepare a joining slurry (referred to as joining slurry 32). In step S2b, the joining slurry 32 is applied (supplied) to a portion excluding the groove 14 in the joining surface 12a of the first ceramic molded body 10A. Thereafter, in step S2c, the first bonded body 30A shown in FIG. 4A is obtained by pressure bonding together with the bonded surface 12b of the second ceramic molded body 10B.

Then, in step S3 of FIG. 1, the first bonded body 30A is fired to obtain a sintered body (first ceramic tube 24A). As shown in FIG. 4B, the first ceramic tube 24A has a bulging portion (light emitting portion 34) formed by joining and firing the curved portion 28 at the center, and electrode sealing formed integrally at both ends of the light emitting portion 34, respectively. And a hollow portion 37 communicating from one electrode introduction portion 36 to the other electrode introduction portion 36 is formed therein. A first through hole 38a (pore) is formed in the middle portion of the light emitting portion 34 of the first ceramic tube 24A by the groove 14 formed in the joining surface 12a of the first ceramic molded body 10A. The first through hole 38a is used as an introduction hole for introducing a luminescent substance into the light emitting portion 34 in the process of manufacturing the first ceramic tube 24A as an arc tube, for example. Therefore, the first through hole 38a is sealed after the introduction of the luminescent substance or the like. In addition to the inert start gas such as argon, mercury and a metal halide additive are enclosed inside the light emitting unit 34. However, it is not always necessary to enclose mercury.

Here, for comparison, a conventional manufacturing method for producing a ceramic tube having a through hole will be described with reference to FIG.

In step S11 of FIG. 5, two second ceramic molded bodies 10B having no grooves 14 on the joining surface 12b are produced.

Specifically, in step S11a, a molding slurry 16 is prepared by mixing ceramic powder, a dispersion medium, a gelling agent, and the like. In step S11b, the molding slurry 16 is cast into a second casting mold 18B for the second ceramic molded body 10B (see FIG. 3B), solidified, and then released from the second casting mold 18B. A second ceramic molded body 10B is obtained.

In step S12 of FIG. 5, a through hole is provided in the curved portion 28 of one second ceramic molded body 10B by, for example, drilling with a drill.

In step S13 of FIG. 5, the two second ceramic molded bodies 10B are joined.

Specifically, in step S13a, a ceramic powder, a solvent, a binder, and the like are mixed to prepare a joining slurry. In step S13b, the bonding slurry 32 is applied (supplied) to the bonding surface 12b of one second ceramic molded body 10B. Thereafter, in step S13c, the joined surfaces 12b of the two second ceramic molded bodies 10B are put together and bonded together to obtain a joined body.

Then, in step S14 of FIG. 5, the joined body is fired to obtain a sintered body (ceramic tube) in which through holes are formed.

In this conventional manufacturing method, since the through-hole is processed with a drill for the curved portion 28 of one second ceramic molded body 10B, the second ceramic molded body 10B is moved by the rotational vibration of the drill, In some cases, a through hole having a desired diameter cannot be formed. Therefore, the second ceramic molded body 10B is held and fixed with a jig or the like. However, it is necessary to hold and fix the second ceramic molded body 10B with such a strength that the second ceramic molded body 10B is not broken. is there. Moreover, it is necessary to prepare a jig and a drill in advance according to the size of the second ceramic molded body 10B, and there is a problem that the manufacturing cost is increased. In addition, since the second ceramic molded body 10B is damaged due to rotational vibration by a drill, collision of cutting waste, or the like, there is a possibility that cracks are likely to occur after the ceramic tube is formed.

On the other hand, in the first manufacturing method, the first ceramic molded body 10A having the groove 14 on the joining surface 12a and the second ceramic molded body 10B having no groove 14 on the joining surface 12b are joined, and the groove 14 is used. Since the first ceramic tube 24A in which the first through hole 38a is formed is manufactured, it is not necessary to perform drilling with a drill, simplifying the manufacturing process, reducing the number of steps, improving the throughput, and improving the yield. The improvement can be achieved, and the productivity of the first ceramic tube 24A having the first through hole 38a for introducing the luminescent material can be improved. And since a drill is not used, when it is set as the 1st ceramic tube 24A, generation | occurrence | production of the damage | wound which becomes a cause of generation | occurrence | production of a crack or a leak can be avoided. In addition, although the metal mold | die for obtaining the 1st ceramic molded object 10A is needed, when compared with the metal mold | die for obtaining the 2nd ceramic molded object 10B, the shape of this metal mold | die is the shape which reversed the groove | channel 14. Since the shape is simple with only the protrusions 20, the mold can be manufactured at low cost, and the cost can be increased when considering the above-described simplification of the manufacturing process, reduction in man-hours, improvement in throughput, improvement in yield, etc. Not connected.

In the above-described example, the example in which the first through holes 38a are formed in the intermediate portion of the light emitting portion 34 with the heights of the curved portions 28 of the first ceramic molded body 10A and the second ceramic molded body 10B being the same is shown. However, as shown in FIG. 6A, for example, the height of the curved portion 28 of the first ceramic molded body 10A may be larger than the height of the curved portion 28 of the second ceramic molded body 10B. The reverse is also possible. In this case, as shown in FIG. 6B, when the first ceramic tube 24A is formed, the first through hole 38a is located closer to one electrode introduction portion 36 or closer to the other electrode introduction portion 36 from the intermediate portion of the light emitting portion 34. It will be formed at an eccentric position.

Next, in the manufacturing method according to the second specific example (hereinafter referred to as the second manufacturing method), in step S101 of FIG. 7, as shown in FIG. A ceramic molded body 10A is produced.

Specifically, ceramic powder, a dispersion medium, a gelling agent, and the like are mixed to prepare a molding slurry 16 (step S101a in FIG. 7), and then the molding slurry 16 is cast into the first casting mold 18A ( Step S101b) solidifies. Thereafter, the first ceramic mold 10A is obtained by releasing the first casting mold 18A (step S101c).

As shown in FIG. 8, the length along the axis n1 of the groove 14 formed in the joint surface 12a of the first ceramic molded body 10A is the same as the thickness of the curved portion 28 of the first ceramic molded body 10A. The length (width) orthogonal to the axis n1 of the groove 14 needs to be 1 to 3 times the diameter of the luminescent material inserted in the solid state, so the diameter of the inscribed circle is φ0.25 mm. It is set to ~ 0.9mm.

7 In step S102 of FIG. 7, the two first ceramic molded bodies 10A are joined together. Specifically, after mixing ceramic powder, a solvent, a binder, and the like to prepare a bonding slurry 32 (step S102a), the bonding surface 12a of one first ceramic molded body 10A is bonded to a portion excluding the groove 14. The slurry 32 is applied (supplied) (step S102b). Thereafter, as shown in FIG. 9A, the joined surfaces 12a of the two first ceramic molded bodies 10A are bonded together to obtain a second joined body 30B (step S102c).

Then, in step S103 of FIG. 7, the second bonded body 30B is fired to obtain a sintered body (second ceramic tube 24B). As shown in FIG. 9B, the second ceramic tube 24B has a light emitting part 34 formed by joining and firing a curved part 28 at the center part, and electrode introducing parts 36 integrally formed at both ends of the light emitting part 34, respectively. The hollow portion 37 that communicates from one electrode introduction portion 36 to the other electrode introduction portion 36 is formed inside. A second through hole 38b (a through hole formed by the grooves 14 facing each other) is formed in the middle portion of the light emitting portion 34 of the second ceramic tube 24B by the grooves 14 formed in the joint surfaces 12a of the two first ceramic molded bodies 10A. ) Is formed. The second through hole 38b is used as an introduction hole for introducing a luminescent substance into the light emitting portion 34 in the process of manufacturing the second ceramic tube 24B as, for example, a light emitting tube.

In the second manufacturing method, similarly to the first manufacturing method described above, it is not necessary to perform drilling with a drill, and the manufacturing process is simplified, man-hours are reduced, throughput is improved, and yield is improved. Thus, the productivity of the second ceramic tube 24B having the second through hole 38b for introducing the luminescent material can be improved. In particular, in this second manufacturing method, since only the first casting mold 18B for producing the first ceramic molded body 10A is required as the casting mold to be prepared, the cost is further reduced.

In the above-described example, the example in which the second through-holes 38b are formed in the intermediate portion of the light-emitting portion 34 with the heights of the curved portions 28 of the first ceramic molded body 10A being the same is shown. Similarly to the case of 6A, for example, the height of the curved portion 28 of one first ceramic molded body 10A may be larger than the height of the curved portion 28 of the other first ceramic molded body 10A. The reverse is also possible. In this case, when the second ceramic tube 24B is formed, the second through hole 38b is formed at an eccentric position near the one electrode introduction portion 36 or the other electrode introduction portion 36 from the intermediate portion of the light emitting portion 34. It will be.

Next, a method for manufacturing a ceramic tube according to the second embodiment will be described.

The second embodiment has at least one ceramic having a first protrusion that constitutes a part of the joint surface, and a through groove is continuously formed on the joint surface from the end of the first protrusion to the inside. A hole formed by the through groove is formed, which includes a molded body manufacturing step for manufacturing a plurality of ceramic molded bodies including a molded body, and a molded body bonding step for bonding the bonding surfaces of the plurality of ceramic molded bodies. It is characterized by producing a ceramic tube.

Some specific examples of the method of manufacturing a ceramic tube according to the second embodiment will be described with reference to FIGS.

First, a manufacturing method according to a third specific example (hereinafter referred to as a third manufacturing method) includes one third ceramic molded body 10C and one first ceramic body as shown in FIG. 4 ceramic molded body 10D is produced. The third ceramic molded body 10C has a first protrusion 40a that constitutes a part of the joint surface 12c, and is continuous with the joint surface 12c from the end of the first protrusion 40a to the inside of the third ceramic molded body 10C. Thus, a through groove 42 is formed. The fourth ceramic molded body 10D has a second protrusion 40b that constitutes a part of the bonding surface 12d. The through-groove 42 is not formed on the joining surface 12d of the fourth ceramic molded body 10D from the end of the second protrusion 40b to the inner side of the fourth ceramic molded body 10D, and is a flat surface.

Specifically, in step S201a of FIG. 10, a molding slurry 16 is prepared by mixing ceramic powder, a dispersion medium, a gelling agent, and the like. In step S201b, as shown in FIGS. 12A and 12B, the molding slurry 16 is fed into the third casting mold 18C for the third ceramic molded body 10C (see FIG. 12A) and the fourth for the fourth ceramic molded body 10D. After casting into a casting mold 18D (see FIG. 12B), it solidifies. Thereafter, the third casting mold 10C and the fourth ceramic molding 10D are obtained by releasing the third casting mold 18C and the fourth casting mold 18D. In the third casting mold 18C, a first space 44a for forming the first protrusion 40a and the through groove 42 is formed in a portion where the joining surface 12c is formed, and the joining surface 12d is formed in the fourth casting mold 18D. A second space 44b for forming the second protrusion 40b is formed in the part to be molded.

The third ceramic molded body 10 </ b> C and the fourth ceramic molded body 10 </ b> D are both formed in a cylindrical shape having a hollow portion 22. More specifically, the third ceramic molded body 10C and the fourth ceramic molded body 10D are similar in shape in which the third ceramic tube 24C (see FIG. 15B), which is a finished product, is separated into two at the longitudinal center of the axis m1. In particular, the third ceramic molded body 10C has a shape in which the cylindrical portion 26, the curved portion 28 (saddle shape), and the first protrusion 40a are integrally formed, and the fourth ceramic molded body 10D has a shape. The cylindrical portion 26, the curved portion 28 (saddle shape), and the second protrusion 40 b are integrally formed.

The

joint surfaces

12c and 12d of the third ceramic molded body 10C and the fourth ceramic molded body 10D are located on the end surfaces of the curved portions 28, and are axial with respect to the third ceramic molded body 10C and the fourth ceramic molded body 10D. Parallel to the orthogonal plane. The joint surface 12c of the third ceramic molded body 10C is formed with the above-described through groove 42 formed continuously from the end of the first protrusion 40a toward the inside of the third ceramic molded body 10C. . As shown in FIG. 11, the first protrusion 40a is projected in a direction in which the axis line n2 is directed to the axis line m3 of the third ceramic molded body 10C and the angle formed between the axis line n2 and the axis line m3 is 90 °. Alternatively, as shown in FIGS. 13 and 14, when the intersection of the outer periphery of the joint surface 12c having the first protrusion 40a and the axis n2 of the first protrusion 40a is the base point 46 of the first protrusion 40a. Further, the angle θ formed by the direction of the tangent line K1 at the base point 46 on the outer periphery of the joint surface 12c and the axis n2 of the first protrusion 40a may be protruded in a direction of 30 ° to 60 °. The same applies to the second protrusion 40b.

The length along the axis n2 of the through groove 42 is the same as the sum of the height of the first protrusion 40a and the thickness of the curved portion 28 of the third ceramic molded body 10C, and is a length orthogonal to the axis n2 of the through groove 42. The length (width) is required to be 1 to 3 times the diameter of the light-emitting substance to be inserted, so that the diameter of the inscribed circle is set to φ0.25 mm to φ0.9 mm. Although not shown, the outer peripheral portion and the inner peripheral portion of each

joint surface

12c and 12d of the third ceramic molded body 10C and the fourth ceramic molded body 10D may be chamfered (for example, C surface).

In step S202 of FIG. 10, the third ceramic molded body 10C and the fourth ceramic molded body 10D are joined.

Specifically, in step S202a, a ceramic powder, a solvent, a binder and the like are mixed to prepare a joining slurry. In step S202b, the bonding slurry is applied (supplied) to a portion of the bonding surface 12c of the third ceramic molded body 10C excluding the through groove 42. Thereafter, in step S202c, the bonding surface 12c of the third ceramic molded body 10C and the bonding surface 12d of the fourth ceramic molded body 10D are bonded together to obtain a third bonded body 30C (see FIG. 15A). At this time, the bonding surface 12c of the first protrusion 40a and the bonding surface 12d of the second protrusion 40b are opposed to each other.

Then, in step S203 of FIG. 10, the third bonded body 30C is fired to obtain a sintered body (third ceramic tube 24C). As shown in FIG. 15B or FIG. 16A, the third ceramic tube 24C includes a light emitting part 34 formed by joining and firing a curved part 28 at the center part, and an electrode introducing part 36 integrally formed at both ends of the light emitting part 34, respectively. And has a shape in which a hollow part 37 communicating from one electrode introduction part 36 to the other electrode introduction part 36 is formed. The light emitting portion 34 of the third ceramic tube 24C is formed with a cylindrical protrusion 50 (a thin tube) that protrudes outward from a part of the light emitting portion 34.

A cylindrical protrusion 50 shown in FIG. 15B is formed by joining and firing the first protrusion 40a and the second protrusion 40b shown in FIG. 11, and the axis n3 thereof is the third ceramic tube 24C. It faces the axis m1 and protrudes in a direction in which the angle formed by the axis n3 and the axis m1 is 90 °. The cylindrical protrusion 50 shown in FIG. 16A is formed by joining and firing the first protrusion 40a and the second protrusion 40b shown in FIG. 13, and as shown in FIG. 16B, the light emitting portion 34 is formed. When the outer surface of the contour line 52 is cut by a plane including the axis n3 of the cylindrical projection 50 and the relationship between the contour line 52 and the axis n3 of the projection 50, the contour line 52 at the intersection 54 of the contour line 52 and the axis n3 is obtained. The angle formed by the direction of the tangent line K2 and the axis line n3 projects in a direction of 30 ° to 60 °.

Further, the cylindrical protrusion 50 has a third through hole 38c formed by the through groove 42 of the first protrusion 40a along the axis n3. The third through hole 38c is used as an introduction hole for introducing a luminescent substance into the light emitting portion 34 in the process of manufacturing the third ceramic tube 24C as an arc tube, for example.

Here, for comparison, a conventional manufacturing method for producing a sintered body having a cylindrical protrusion will be described with reference to FIG.

In step S211 (steps S211a to S211c) in FIG. 17, two second ceramic molded bodies 10B having no groove 14 on the joining surface 12b are produced. In step S212, a through hole is provided in the curved portion 28 of one second ceramic molded body 10B, for example, by drilling with a drill. In step S213 (steps S213a to S213c), the two second ceramic molded bodies 10B are joined. Thereafter, in step S214, a joining slurry is applied to the end face of the pipe formed of the ceramic molded body, and the pipe is joined so as to close the through hole to obtain a joined body. In step S215, the joined body is fired to obtain a sintered body (ceramic tube) on which cylindrical protrusions are formed.

In this conventional manufacturing method, since the through-hole is processed with a drill in the curved portion 28 of one second ceramic molded body 10B, in addition to the disadvantages described above, a step of manufacturing a pipe and a pipe are joined. Since a process is required, the entire manufacturing process becomes complicated, and there is a problem that the manufacturing cost is increased.

On the other hand, in the third manufacturing method, as in the first manufacturing method described above, it is not necessary to perform drilling with a drill, simplifying the manufacturing process, reducing the number of steps, improving the throughput, and improving the yield. Improvement can be achieved, and improvement in the productivity of the third ceramic tube 24C having the third through hole 38c for introducing the luminescent material can be realized. In particular, the first protrusion 40a having the through groove 42 and the second protrusion 40b are joined to form the cylindrical protrusion 50 having the third through hole 38c for introducing the luminescent material. The projection 50 acts as a guide for the introduction of the luminescent material and the exhaust of the gas, and the introduction of the luminescent material and the exhaust of the gas become easy. Further, the third through hole 38c can be easily sealed. For example, it is preferable to employ a method in which the tip of the cylindrical projection 50 is sealed by thermal fusion with a laser beam or the like, or a sealing member is packed into the tip of the cylindrical projection 50 in the third through hole 38c. And the sealing work is simplified.

Since the cylindrical protrusion 50 shown in FIG. 15B protrudes in a direction perpendicular to the axis m1 of the third ceramic molded body 10C, as shown in FIG. 18A, the protrusion amount La (of the light emitting portion 34) of the protrusion 50 is obtained. When the distance between the line segment connecting the center Oa and the tip point Pa of the projection 50 and the outer periphery of the light emitting portion 34 is large (distance from the tip point Pa to the tip point Pa), the completed arc tube is put into an outer sphere and ramped. It is necessary to increase the diameter of the outer sphere, which makes it difficult to reduce the size of the lamp. Moreover, it becomes easy to contact other objects, such as a lead wire in an outer sphere, and it becomes easy to break. Further, the tip portion (the portion to be sealed) of the protrusion 50 is far from the light emitting portion 34, and the tip portion becomes the coldest point. For this reason, corrosive luminescent substances are likely to accumulate, and when used as an arc tube, corrosion or the like may occur in the sealed portion. On the contrary, if the protrusion amount La of the protrusion 50 is too small, when the third through-hole 38c is heat-sealed, the volume to be dissolved is insufficient, or the sealing distance is shortened even when the sealing member is stuffed. There is a risk that sealing will be difficult, such as the occurrence of spillage. Therefore, the protrusion amount La of the protrusion 50 is preferably in the range of 1/20 to 10/20 of the maximum diameter of the light emitting portion 34, more preferably 2/20 to 5/20.

On the other hand, when the cylindrical protrusion 50 shown in FIG. 16A is formed, the protrusion amount La of the protrusion 50 can be shortened as shown in FIG. 18B. It is difficult to cause contact or damage to the object. Moreover, since the tip portion is closer to the light emitting portion 34 than in the case of FIG. 18A, it is possible to avoid the tip portion from becoming the coldest point, and when used as an arc tube, Corrosion and the like can be prevented, leading to improved reliability.

In the above-described example, the example in which the cylindrical protrusions 50 are formed in the intermediate portion of the light emitting portion 34 with the heights of the curved portions 28 of the third ceramic molded body 10C and the fourth ceramic molded body 10D being the same is shown. However, similarly to the case of FIG. 6A described above, for example, the height of the curved portion 28 of the third ceramic molded body 10C may be larger than the height of the curved portion 28 of the fourth ceramic molded body 10D. The reverse is also possible. In this case, when the third ceramic tube 24C is formed, the cylindrical protrusion 50 is formed at an eccentric position near the one electrode introduction portion 36 or the other electrode introduction portion 36 from the intermediate portion of the light emitting portion 34. It will be.

Next, the manufacturing method according to the fourth specific example (hereinafter referred to as the fourth manufacturing method) includes two third ceramic molded bodies 10C as shown in FIGS. 20 and 21 in step S301 of FIG. Make it.

Specifically, after mixing a ceramic powder, a dispersion medium, a gelling agent and the like to prepare a molding slurry (step S301a in FIG. 19), the molding slurry is cast into the third casting mold 18C (step S301b). ), Solidify. Thereafter, the third ceramic molded body 10C is obtained by releasing from the third casting mold 18C (step S301c).

The length along the axis n2 of the through groove 42 formed on the joint surface 12c of the third ceramic molded body 10C is the sum of the height of the first protrusion 40a and the thickness of the curved portion 28 of the third ceramic molded body 10C. Since the length (width) orthogonal to the axis n2 of the through groove 42 is required to be 1 to 3 times the diameter of the light emitting material to be inserted, the diameter of the inscribed circle is φ0. 25 mm to φ0.9 mm.

In step S302 of FIG. 19, two third ceramic molded bodies 10C are joined. Specifically, after mixing a ceramic powder, a solvent, a binder, and the like to prepare a bonding slurry 32 (step S302a), a portion of the bonding surface 12c of one third ceramic molded body 10C excluding the through groove 42 is prepared. The joining slurry 32 is applied (supplied) (step S302b). After that, the fourth bonded body 30D (see FIG. 22A) is obtained by bonding and bonding the bonding surfaces 12c of the two third ceramic molded bodies 10C together (step S302c).

In step S303 in FIG. 19, the fourth bonded body 30D is fired to obtain a sintered body (fourth ceramic tube 24D). As shown in FIG. 22B or FIG. 23, the fourth ceramic tube 24D includes a light emitting part 34 formed by joining and firing a curved part 28 at the center part, and an electrode introducing part 36 integrally formed at both ends of the light emitting part 34, respectively. And has a shape in which a hollow part 37 communicating from one electrode introduction part 36 to the other electrode introduction part 36 is formed. The light emitting portion 34 of the fourth ceramic tube 24D has a fourth through hole 38d formed by a through groove 42 formed in each joint surface 12c of the two third ceramic molded bodies 10C (through hole due to the through grooves 42 facing each other). Is formed. The fourth through hole 38d is used as an introduction hole for introducing a luminescent substance into the light emitting unit 30 in the process of manufacturing the fourth ceramic tube 24D as an arc tube, for example. Also in the protrusion of the fourth ceramic tube 24D, in the case of the configuration shown in FIG. 22B, the protrusion amount of the protrusion 50 is preferably in the range of 1/20 to 10/20 of the maximum diameter of the light emitting portion 34, more preferably 2 / 20 to 5/20. In the case of the configuration shown in FIG. 23, the protrusion amount of the protrusion 50 can be shortened, and when the lamp is formed, the size can be reduced, and contact with or damage to other objects hardly occurs. Moreover, since the tip portion is closer to the light emitting portion 34 than in the case of FIG. 22B, it is possible to avoid the tip portion from becoming the coldest point, and when used as a light emitting tube, Corrosion and the like can be prevented, leading to improved reliability.

In the fourth manufacturing method, similarly to the first manufacturing method described above, it is not necessary to perform drilling with a drill, and the manufacturing process is simplified, man-hours are reduced, throughput is improved, and yield is improved. Thus, the productivity of the fourth ceramic tube 24D having the fourth through hole 38d for introducing the luminescent material can be improved. Further, similarly to the third manufacturing method described above, the introduction of the luminescent material and the exhaust of the gas are facilitated, and the fourth through hole 38d can be easily sealed. In particular, in the fourth manufacturing method, since only the third casting mold 18C for producing the third ceramic molded body 10C is required as the casting mold to be prepared, the cost is further reduced.

In the above-described example, the example in which the cylindrical protrusions 50 are formed in the intermediate portion of the light emitting unit 34 with the heights of the curved portions 28 of the two third ceramic molded bodies 10C being the same is shown. Similarly to the case of FIG. 6A, for example, the height of the curved portion 28 of one third ceramic molded body 10C may be made larger than the height of the curved portion 28 of the other third ceramic molded body 10C. The reverse is also possible. In this case, when the fourth ceramic tube 24d is formed, the cylindrical protrusion 50 is formed at an eccentric position near the one electrode introduction portion 36 or the other electrode introduction portion 36 from the intermediate portion of the light emitting portion 34. It will be.

Here, preferable modes of materials and the like used in the manufacturing method according to the present embodiment will be described. Note that the above-described first to fourth manufacturing methods are collectively referred to as “manufacturing method”. Further, when the first ceramic molded body 10A to the fourth ceramic molded body 10D are not distinguished and referred to, they are simply referred to as “ceramic molded body 10”, and when the joint surfaces 12a to 12d are not distinguished and referred to, When the first through hole 38a to the fourth through hole 38d are not distinguished and referred to simply as “joining surface 12”, they are simply referred to as “through hole 38”.

(Ceramic molded body)
In the manufacturing method described above, the ceramic molded body 10 is prepared. Various methods are conventionally known for producing the ceramic molded body 10 and can be easily obtained using such methods. As a manufacturing method of the ceramic molded body 10, for example, a molding slurry 16 containing an inorganic powder and an organic compound is cast into a casting mold, and a chemical reaction between organic compounds, for example, a chemical reaction between a dispersion medium and a gelling agent or a gelling agent. After solidifying, it can be prepared by a gel casting method for releasing the mold. Such a forming slurry 16 contains a dispersion medium and a gelling agent in addition to the raw material powder, and may contain a dispersing agent and a catalyst for adjusting viscosity and solidification reaction. Hereinafter, these various components will be described.

(Raw material powder)
Examples of the ceramic powder contained in the ceramic molded body 10 include alumina, aluminum nitride, zirconia, YAG, and a mixture of two or more thereof. Examples of the sintering aid for improving the sinterability and characteristics include magnesium oxide, and ZrO ₂ , Y ₂ O ₃ , La ₂ O ₃ and Sc ₂ O ₃ are preferable.

(Dispersion medium)
As the dispersion medium, it is preferable to use a reactive dispersion medium. For example, it is preferable to use an organic dispersion medium having a reactive functional group. The organic dispersion medium having a reactive functional group is chemically bonded to a gelling agent to be described later, that is, a liquid substance capable of solidifying the molding slurry 16, and a highly fluid molding slurry 16 that is easy to cast. It is preferable to satisfy the two conditions of being any liquid substance that can be formed. In order to chemically bond with the gelling agent and solidify the molding slurry 16, a reactive functional group, that is, a functional group capable of forming a chemical bond with the gelling agent such as a hydroxyl group, a carboxyl group, or an amino group is formed in the molecule. It is preferable to have.

On the other hand, in order to form the molding slurry 16 having high fluidity that can be easily cast, it is preferable to use an organic dispersion medium having a viscosity as low as possible, and in particular, a substance having a viscosity of 20 cps or less at a temperature of 20 ° C. is used. It is preferable to do.

Further, if the amount of polyhydric alcohol or polybasic acid is an amount that does not greatly increase the viscosity of the molding slurry 16, it is effective to use it for strength reinforcement.

(Gelling agent)
The gelling agent reacts with a reactive functional group contained in the dispersion medium to cause a solidification reaction, and is described in, for example, International Publication No. 2002/085590 pamphlet. Can do.

The reactive functional group of the gelling agent does not cause deformation of the groove shape by causing a solidification reaction and then deforming the groove shape in order to perform bonding while maintaining the groove shape. It is desirable to have a strength sufficient to prevent deformation with a load of. From this point of view, an isocyanate group (—N═C═O) and / or an isothiocyanate group (—having a high solvent resistance after the solidification reaction and a high reactivity with the reactive dispersion material in particular. It is preferred to select a gelling agent having N = C = S).

The molding slurry 16 for producing the ceramic molded body 10 can be exemplified by the contents described in Japanese Patent Application Laid-Open No. 2008-44344 and International Publication No. 2002/085590, for example, prepared as follows. can do. That is, first, the raw material powder is dispersed in the dispersion medium to form the molding slurry 16, and then the gelling agent is added, or the raw material powder and the gelling agent are added to the dispersion medium simultaneously and dispersed to form the molding slurry 16. It can be.

(Joining slurry)
In order to obtain a bonded body, a bonding slurry 32 for bonding the ceramic molded bodies 10 to each other is prepared. The joining slurry 32 is preferably a non-self-curing slurry that does not solidify due to a chemical reaction. Since it is a non-self-curing slurry, a layer of the bonding slurry 32 is formed in a state in which surface tension is applied. Therefore, the shape of the layer of the bonding slurry 32 is easily controlled to clog pores obtained after bonding. , It will be possible to prevent deformation.

As the joining slurry 32, various binders such as polyvinyl acetal resin and ethyl cellulose can be used in addition to the raw material powder and the non-reactive dispersion medium that can be used for the molding slurry 16 described above.

The joining slurry 32 can be obtained by mixing the raw material powder, the solvent, and the binder by using a normal ceramic paste or slurry manufacturing method using a tri-roll mill, a pot mill, or the like. A dispersant and an organic solvent can be appropriately mixed. Specifically, butyl carbitol, butyl carbitol acetate, terpineol, or the like can be used. The viscosity of the bonding slurry 32 at a temperature of 20 ° C. is preferably 10,000 cps or more and 400,000 cps or less. Within this range, the bonding slurry 32 layer is appropriately deformed during bonding, so that bubbles can be prevented from remaining in the bonding slurry 32 layer. In addition, it is convenient for forming the bonding slurry 32 layer. This is because a good surface tension can be maintained, so that the groove of the ceramic molded body 10 can be avoided from being filled. More preferably, it is 30000 cps or more and 200000 cps or less. In this range, since the supply shape of the joining slurry 32 can be made clear, even when the diameter of the through hole 38 is φ0.6 mm or less, the through hole 38 after joining is deformed of the joining slurry 32, By protruding, it is not buried and can be controlled to a desired shape.

(Preparation of joined body)
Next, the prepared two or more ceramic molded bodies 10 are joined using the joining slurry 32 to produce a joined body.

(Joint slurry layer forming process)
In order to obtain a bonded body, first, a layer of the bonding slurry 32 is formed by maintaining a state in which surface tension acts between the bonding surfaces 12 of the two or more ceramic molded bodies 10 to be bonded to each other. Form. At this time, it is desirable not to supply the joining slurry 32 to the groove portion provided in the ceramic molded body 10 from the viewpoint of preventing clogging or deformation of the through hole 38 after joining.

In order to supply the bonding slurry 32 between the bonding surfaces 12 of the ceramic molded body 10, known methods such as dispenser, dipping, spraying, screen printing, and metal mask printing can be used.

For example, when the thickness of the layer of the bonding slurry 32 supplied onto the bonding surface 12 of the ceramic molded body 10 is 200 μm or less (preferably 10 μm or more), it is preferable to supply the bonding slurry 32 by screen printing. According to the screen printing, the joining slurry 32 can be supplied with high precision and uniform thickness, and the joining slurry 32 can be formed in the groove portion of the molded body by appropriately designing the screen plate-making pattern. The supply location such as no supply can be selected, and clogging or deformation of the through hole 38 can be prevented. For this reason, it is possible to obtain an accurate through-hole 38 that is free from clogging and deformation due to protrusion of the joining slurry 32. If the thickness of the layer of the joining slurry 32 is too thin, bubbles are likely to remain. If the thickness is too thick, the through-holes 38 are likely to be clogged due to deformation of the joining slurry 32 during joining. Therefore, the thickness of the layer of the bonding slurry 32 after bonding is preferably 5 μm to 100 μm, and the amount of the bonding slurry 32 to be supplied is preferably adjusted so as to be within this range. In particular, when the diameter of the through hole 38 is φ0.6 mm or less, the thickness of the layer of the bonding slurry 32 after bonding is preferably 5 μm to 40 μm, and the bonding slurry 32 supplied so as to fall within this range is used. It is preferable to adjust the amount.

In order to maintain the surface tension of the bonding slurry 32 and to form a layer of the bonding slurry 32 without generating bubbles, the bonding slurry 32 needs to be deformed to some extent during bonding. What is necessary is just to hold | maintain between the joining surfaces 12 of the ceramic molded body 10 at the intended distance, without drying, after supplying the joining slurry 32 between the joining surfaces 12 of the body 10, or the joining surface 12. FIG. When the bonding slurry 32 is non-self-curing, after being supplied to the bonding surface 12 and the like and before drying, it is held for a certain period by surface tension, but deformed by external force. This is because a possible state is easily maintained.

In particular, it is possible to easily control the thickness of the layer of the bonding slurry 32 by securing the degree of the load applied in the direction orthogonal to the bonding surface 12 and / or the distance between the bonding surfaces 12, and the bonding slurry 32 having a desired thickness. This makes it easier to obtain a through hole 38 having a desired shape without clogging or deformation.

(Drying process)
When the layer of the bonding slurry 32 is formed between the bonding surfaces 12 of the ceramic molded body 10 arranged to face each other, the layer of the bonding slurry 32 is dried. The drying process can be appropriately set according to the composition and supply amount of the bonding slurry 32. Usually, it can be carried out at a temperature of 40 ° C. or more and 200 ° C. or less for about 5 to 120 minutes. Further, by applying a load in a direction orthogonal to the bonding surface 12 during drying, it is easy to obtain a layer of the bonding slurry 32 having a desired thickness while suppressing generation of bubbles due to drying shrinkage of the layer of the bonding slurry 32.

The thus obtained joined body is a state in which at least two ceramic molded bodies 10 are joined by a joined portion (after drying) in which the layer of the joining slurry 32 is dried, and through holes are provided in advance by grooves provided in the ceramic molded body 10. It has become. In the production of the joined body described above, the case where two ceramic molded bodies 10 are joined has been described. However, the present invention is not limited to this, and three or more ceramic molded bodies 10 can be joined simultaneously or sequentially. A layer of the slurry 32 can be formed and bonded to obtain a bonded body.

(Production of sintered body (ceramic tube))
Next, the joined body is fired to sinter the sinterable component in the ceramic molded body 10 and the joined portion (after drying) to obtain a sintered body. Prior to the sintering step, the joined body can be degreased or calcined.

[First embodiment]
The occurrence of cracks in the sintered bodies (ceramic tubes) produced by the production methods according to Examples 1 to 4 and Comparative Examples 1 and 2 and the amount of leakage of the light emitting part were measured.

Example 1
Based on the second manufacturing method shown in FIG. 7, ten second ceramic tubes 24B shown in FIG. 9B were produced.

First, a molding slurry 16 for producing the first ceramic molded body 10A (see FIG. 8) was prepared as follows. That is, 100 parts by weight of alumina powder as a raw material powder and 0.025 part by weight of magnesia, 30 parts by weight of a polybasic acid ester as a dispersion medium, 4 parts by weight of MDI resin as a gelling agent, 2 parts by weight of a dispersant, 0. 2 parts by weight were mixed to form a molding slurry 16.

The molding slurry 16 was cast in an aluminum alloy first casting mold 18A (see FIG. 3A) at room temperature, left at room temperature for 1 hour, solidified, and then released. Further, it was allowed to stand at room temperature and then at a temperature of 90 ° C. for 2 hours to obtain 20 first ceramic molded bodies 10A. The chamfering (for example, the R surface) of the outer peripheral portion and the inner peripheral portion of each joint surface 12a of the first ceramic molded body 10A was performed within a radius of 0.05 to 0.15 mm.

The joining slurry 32 was prepared as follows. That is, 100 parts by weight of alumina powder, 0.025 parts by weight of magnesia, 100 parts by weight of terpineol, 30 parts by weight of butyl carbitol, and 8 parts by weight of polyvinyl acetal resin were mixed as a raw material powder to form a joining slurry 32.

As the screen plate making, an emulsion thickness of 100 μm, # 290 mesh, and a ring-shaped pattern 62 (inner diameter 12.8 mm) having notches 60 corresponding to the grooves 14 of the first ceramic molded body 10A as shown in FIG. And a screen plate having an outer diameter of 13.7 mm). Then, the screen plate was fixed to the stage of the screen printing machine so as to be parallel to the joining surface 12a (inner diameter 12.5 mm, outer diameter 14.0 mm) of the first ceramic molded body 10A, and was aligned with the screen plate making. . Next, the prepared bonding slurry 32 was supplied to the bonding surface 12a of the first ceramic molded body 10A using a screen printing machine with a screen printing machine. Thereafter, the bonding surfaces 12a of the pair of first ceramic molded bodies 10A were respectively pressure-bonded and dried for 15 minutes with a drier at a temperature of 95 ° C., thereby producing ten second bonded bodies 30B (see FIG. 9A).

Next, the second bonded body 30B manufactured as described above is calcined in the atmosphere at a temperature of 1200 ° C., and then fired at a temperature of 1800 ° C. in an atmosphere of hydrogen: nitrogen = 3: 1, thereby densifying and translucent. Made it. As a result, as shown in FIG. 9B, the light emitting portion 34 has a second through hole 38b, the light emitting portion 34 has an outer diameter of 11 mm, and the electrode introduction portion 36 has a length of 17 mm (second ceramic tube). 24B) was obtained.

None of the ten sintered bodies (second ceramic tube 24B) obtained in Example 1 were found to be cracked or deformed. When the thermal shock resistance was evaluated by an underwater quenching method, each sintered body did not generate cracks even at a temperature of 150 ° C., and was at the same level as a ceramic tube having the same shape without the second through hole 38b. Further, for these sintered bodies, after the thermal shock resistance evaluation, the second through-hole 38b formed in the light emitting portion 34 is blocked, and the leakage amount of the light emitting portion 34 is measured with a He (helium) leak measuring machine. , Both were 1 × 10 ⁻⁸ atm · cc / sec or less.

(Example 2)
Based on the 4th manufacturing method shown in FIG. 19, the 10 sintered compacts (4th ceramic tube 24D) which concern on Example 2 shown to FIG. 22B were produced.

First, a molding slurry 16 was prepared in the same manner as in Example 1 described above, and this molding slurry 16 was cast into a third casting mold 18C (see FIG. 12A) made of an aluminum alloy at room temperature and left at room temperature for 1 hour. Then, after solidifying, the mold was released. Furthermore, it was left to stand at room temperature and then at a temperature of 90 ° C. for 2 hours to obtain 20 third ceramic molded bodies 10C. The first protrusions 40a of each third ceramic molded body 10C were adjusted so that the projecting amount was 4.0 mm, the outer width was 0.9 mm, and the width of the through groove 42 was 0.3 mm in the dimensions after firing shrinkage. . Also in this case, the outer peripheral portion and the inner peripheral portion of each joint surface 12c of the third ceramic molded body 10C were chamfered.

The joining slurry 32 was prepared in the same manner as in Example 1 described above, and the prepared joining slurry 32 was supplied to the joining surface 12a of the third ceramic molded body 10C using a screen printing machine with a screen printing machine. As in the case of Example 1, the screen plate making was made with an emulsion thickness of 100 μm and # 290 mesh. However, as shown in FIG. 25, the screen plate-making pattern has a notch 64 corresponding to the through groove 42 of the third ceramic molded body 10C, and the joining surface 12c of the third ceramic molded body 10C (the through groove 42 is formed). To form a ring-shaped pattern 68 in which protrusions 66 are formed at opposite ends.

Then, the joint surfaces 12c of the pair of third ceramic molded bodies 10C were respectively pressure-bonded and dried for 15 minutes with a dryer having a temperature of 95 ° C., thereby producing ten fourth joined bodies 30D (see FIG. 22A).

Next, the second bonded body 30B produced as described above was preliminarily fired and fired in the same manner as in Example 1 to be densified and translucent. As a result, as shown in FIG. 22B, the outer diameter of the light emitting portion 34 is 11 mm, the length of the electrode introducing portion 36 is 17 mm, and the light emitting portion 34 protrudes outward from the intermediate portion of the light emitting portion 34. A sintered body (fourth ceramic tube 24D) having a cylindrical projection 50 (projection amount is 4.0 mm and the diameter of the fourth through hole 38d is 0.4 mm) was obtained.

None of the ten obtained sintered bodies according to Example 2 were found to be cracked or deformed. When the thermal shock resistance was evaluated by an underwater quenching method, each sintered body did not generate cracks even at a temperature of 150 ° C., and was at the same level as the arc tube having the same shape without the cylindrical protrusion 50. Furthermore, after evaluating the thermal shock resistance of these sintered bodies, the amount of leak was measured with a He leak measuring machine, and all of them were 1 × 10 ⁻⁸ atm · cc / sec or less.

(Example 3)
In the same manner as in Example 2, a fourth ceramic tube 24D was produced. However, in Example 3, two cylindrical ceramic bodies 10C each having a different height of the curved portion 28 are joined, so that the cylindrical protrusion 50 is moved from the intermediate portion of the light emitting portion 34 to one electrode introduction portion. It was formed at a position eccentric by 1 mm toward 36.

In the ten sintered bodies obtained in Example 3, no cracks or deformations were observed. When the thermal shock resistance was evaluated by an underwater quenching method, each sintered body did not generate cracks even at a temperature of 150 ° C., and was at the same level as the arc tube having the same shape without the cylindrical protrusion 50. Furthermore, after evaluating the thermal shock resistance of these sintered bodies, the amount of leak was measured with a He leak measuring machine, and all of them were 1 × 10 ⁻⁸ atm · cc / sec or less.

Example 4
In the same manner as in Example 2, a fourth ceramic tube 24D was produced. However, in Example 4, the two third ceramic molded bodies 10C shown in FIG. 13 are joined, so that the cylindrical protrusion 50 is formed as shown in FIGS. 16A and 16B. Direction of the tangent line K2 at the intersection 54 of the contour line 52 and the axis n3 in the contour line 52 when viewed in relation to the contour line 52 cut by the plane including the axis line n3 of the projection 50 and the axis line n3 of the projection 50 And the axis n3 are projected in a direction of 45 °.

In the ten sintered bodies obtained in Example 4, no cracks or deformations were observed. When the thermal shock resistance was evaluated by an underwater quenching method, each sintered body did not generate cracks even at a temperature of 160 ° C., and was at the same level as the arc tube having the same shape without the cylindrical protrusion 50. Furthermore, after evaluating the thermal shock resistance of these sintered bodies, the amount of leak was measured with a He leak measuring machine, and all of them were 1 × 10 ⁻⁸ atm · cc / sec or less.

(Comparative Example 1)
Ten sintered bodies according to Comparative Example 1 were produced based on the manufacturing method shown in FIG.

First, a molding slurry 16 was prepared in the same manner as in Example 1 described above, and this molding slurry 16 was cast into a second casting mold 18B (see FIG. 3B) made of aluminum alloy at room temperature and left at room temperature for 1 hour. Then, after solidifying, the mold was released. Furthermore, it was allowed to stand at room temperature and then at a temperature of 90 ° C. for 2 hours to obtain 20 second ceramic molded bodies 10B. Next, each curved portion 28 of one of the second ceramic molded bodies 10B was provided with a through hole that was drilled to adjust the diameter after firing shrinkage to be φ0.4 mm.

Thereafter, the joining slurry 32 was prepared in the same manner as in Example 1 described above, and the prepared joining slurry 32 was applied to the joining surface 12b of one second ceramic molded body 10B by using a screen printing machine with a screen printer. Supplied. And each joined surface 12b of a pair of 2nd ceramic molded object 10B was crimped | bonded, and it dried for 15 minutes with the dryer of temperature 95 degreeC, and produced 10 joined bodies. Subsequently, the joined body produced as described above was pre-fired and fired in the same manner as in Example 1 to obtain 10 sintered bodies according to Comparative Example 1.

None of the obtained 10 sintered bodies according to Comparative Example 1 were found to be cracked or deformed. However, when the thermal shock resistance was evaluated by an underwater quenching method, cracks occurred in each sintered body at a temperature of 150 ° C. Furthermore, after evaluating the thermal shock resistance of these sintered bodies, the amount of leak was measured with a He leak measuring machine, and all of them were 1 × 10 ⁻⁸ atm · cc / sec or less.

(Comparative Example 2)
Based on the manufacturing method shown in FIG. 17, ten sintered bodies according to Comparative Example 2 were produced.

First, in the same manner as in Comparative Example 1, 20 second ceramic molded bodies 10B were obtained. Next, each curved portion 28 of one of the second ceramic molded bodies 10B was provided with a through-hole adjusted so that the diameter after firing shrinkage was 0.9 mm by drilling with a drill, for example.

Thereafter, after each pair of second ceramic molded bodies 10B are joined, pipes adjusted to have an outer diameter φ0.9 mm and an inner diameter φ0.4 mm of the ceramic molded body after firing shrinkage are connected to the through holes. Ten bonded bodies were obtained by bonding to the portion. Subsequently, the joined body produced as described above was pre-fired and fired in the same manner as in Example 1 to obtain 10 sintered bodies according to Comparative Example 2.

No cracks or deformations were observed in any of the obtained 10 sintered bodies according to Comparative Example 2. However, when the thermal shock resistance was evaluated by an underwater quenching method, cracks occurred in each sintered body at a temperature of 140 ° C. Furthermore, after the thermal shock resistance evaluation of these sintered bodies, the amount of leak was measured with a He leak measuring machine, and leakage occurred in two of the 10 sintered bodies.

[Second Embodiment]
For Examples 11 to 15 and Reference Examples 1 and 2, the characteristics when the protruding amount of the cylindrical protrusion was changed were confirmed.

(Example 11)
Ten sintered bodies according to Example 11 were produced in the same manner as Example 2 described above. Except that the protrusion amount of the cylindrical protrusion 50 is set to 1/20 (= D / 20) of the maximum diameter D of the light emitting portion 34, it is the same as the sintered body according to the second embodiment.

(Example 12)
Ten sintered bodies according to Example 12 were produced in the same manner as Example 2 described above. Except that the protrusion amount of the cylindrical protrusion 50 is 2D / 20, it is the same as the sintered body according to the second embodiment.

(Example 13)
Ten sintered bodies according to Example 13 were produced in the same manner as Example 2 described above. Except that the protrusion amount of the cylindrical protrusion 50 is 3D / 20, it is the same as the sintered body according to the second embodiment.

(Example 14)
Ten sintered bodies according to Example 14 were produced in the same manner as Example 2 described above. Except for the amount of protrusion of the cylindrical protrusion 50 being 5D / 20, it is the same as the sintered body according to Example 2.

(Example 15)
Ten sintered bodies according to Example 15 were produced in the same manner as Example 2 described above. Except for the amount of protrusion of the cylindrical protrusion 50 being 10D / 20, this is the same as the sintered body according to Example 2.

(Reference Example 1)
Ten sintered bodies according to Reference Example 1 were produced in the same manner as Example 2 described above. Except for the amount of protrusion of the cylindrical protrusion 50 being 0.5 D / 20, this is the same as the sintered body according to Example 2.

(Reference Example 2)
Ten sintered bodies according to Reference Example 2 were produced in the same manner as Example 2 described above. Except for the amount of protrusion of the cylindrical protrusion 50 being 12D / 20, it is the same as the sintered body according to Example 2.

<Evaluation>
The evaluation items are as follows.

・ Check for cracks and deformations Check if the sintered body has cracks or deformations at the stage of obtaining the sintered body ・ Heat-resistant shock resistance If evaluated by an underwater quenching method and cracks occur at a temperature of 140 ℃ “X”, “△” if there was a crack generated at a temperature of 150 ° C., “◯” if there was a crack generated at a temperature of 160 ° C., “No” if there was no crack generated at a temperature of 160 ° C. ◎ ”.

・ Leak inspection After thermal shock resistance evaluation, cover the through hole by thermal fusion and measure the leak amount of the light emitting part 34 with a He leak measuring machine. Out of 10 pieces, it exceeds 1 × 10 ⁻⁸ atm · cc / sec. Confirm the number (evaluation result)
The evaluation results are shown in Table 1.

From this evaluation result, good results were obtained in all of Examples 11 to 15. In particular, in Examples 12 to 14, cracks did not occur even when the thermal shock resistance was 160 ° C. On the other hand, in Reference Example 1, as compared with Examples 11 to 15, sealing with respect to the through hole was difficult, and leakage occurred in 3 of the 10 sintered bodies. In the evaluation of thermal shock resistance, cracks occurred at a temperature of 150 ° C. This is thought to be because the deformation due to heat fusion reached the light emitting portion 34 and the portion was weakened. In Reference Example 2, in the evaluation of thermal shock resistance, cracks occurred at a temperature of 150 ° C., and leaks occurred in two of the ten sintered bodies. This is presumably because the rigidity of the root portion was weakened by fatigue as a result of the cylindrical protrusion being too long.

[Third embodiment]
With respect to Examples 21 to 25 and Reference Examples 11 and 12, as shown in FIGS. 16A and 16B, characteristics when the angle φ formed by the direction of the tangent line K2 at the intersection 54 and the axis n3 of the protrusion 50 is changed are shown. confirmed.

(Example 21)
Ten sintered bodies according to Example 21 were produced in the same manner as Example 4 described above. Except that the angle φ formed by the direction of the tangent line K2 at the intersection 54 and the axis n3 of the protrusion 50 is 30 °, it is the same as the sintered body according to the fourth embodiment.

(Example 22)
Ten sintered bodies according to Example 22 were produced in the same manner as Example 4 described above. The sintered body according to Example 4 is the same as the sintered body except that the formed angle φ is 40 °.

(Example 23)
Ten sintered bodies according to Example 23 were produced in the same manner as Example 4 described above. As in Example 4, the angle φ formed was 45 °.

(Example 24)
Ten sintered bodies according to Example 24 were produced in the same manner as Example 4 described above. The sintered body according to Example 4 is the same as the sintered body except that the formed angle φ is 50 °.

(Example 25)
Ten sintered bodies according to Example 25 were produced in the same manner as Example 4 described above. The sintered body according to Example 4 is the same as the sintered body except that the formed angle φ is 60 °.

(Reference Example 11)
Ten sintered bodies according to Reference Example 11 were produced in the same manner as in Example 4 described above. The sintered body according to Example 4 is the same as the sintered body except that the formed angle φ is 20 °.

(Reference Example 12)
Ten sintered bodies according to Reference Example 12 were produced in the same manner as in Example 4 described above. The sintered body according to Example 4 is the same as the sintered body except that the formed angle φ is 70 °.

<Evaluation>
Since the evaluation items are the same as in the case of the second embodiment described above (Examples 11 to 15, Reference Examples 1 and 2), description thereof is omitted here.

(Evaluation results)
The evaluation results are shown in Table 2.

From this evaluation result, good results were obtained in all of Examples 21 to 25, and no crack was generated even when the thermal shock resistance was 160 ° C. In Reference Example 11, in thermal shock resistance evaluation, cracks occurred at a temperature of 150 ° C., and two of the ten sintered bodies leaked. This is presumably because the protrusion 50 and the light emitting portion 34 were too close, and the light emitting portion 34 was deformed during heat fusion. In Reference Example 12, cracks occurred at a temperature of 160 ° C. in the evaluation of thermal shock resistance.

It should be noted that the ceramic tube manufacturing method and the ceramic tube according to the present invention are not limited to the above-described embodiments, and various configurations can be adopted without departing from the gist of the present invention.

Claims

In a method of manufacturing a ceramic tube, a ceramic tube for a high-intensity discharge lamp is manufactured by joining a plurality of ceramic molded bodies.
A molded body producing step of producing a plurality of ceramic molded bodies (10) including at least one ceramic molded body (10A) having a groove (14) on the joining surface (12a);
A molded body joining step for joining the joint surfaces (12) of the plurality of ceramic molded bodies (10),
A method for producing a ceramic tube, comprising producing a ceramic tube having a through hole (38) formed by the groove (14).
In the manufacturing method of the ceramic tube of Claim 1,
In the molded body manufacturing step, one first ceramic molded body (10A) having the groove (14) on the joining surface (12a) and one first ceramic body (10A) not having the groove (14) on the joining surface (12b). 2 ceramic molded body (10B),
The said molded object joining process joins one said 1st ceramic molded object (10A) and one said 2nd ceramic molded object (10B), The manufacturing method of the ceramic tube characterized by the above-mentioned.
In the manufacturing method of the ceramic tube of Claim 1,
In the molded body production step, two first ceramic molded bodies (10A) having the groove (14) on the joining surface (12a) are produced,
In the molded body joining step, when the two first ceramic molded bodies (10A) are joined, the grooves (14) formed on each joint surface (12a) of the first ceramic molded body (10A) are joined together. A method for manufacturing a ceramic tube, characterized by joining together.
In a method of manufacturing a ceramic tube, a ceramic tube for a high-intensity discharge lamp is manufactured by joining a plurality of ceramic molded bodies.
A first protrusion (40a) constituting a part of the joint surface (12a) is provided, and the through groove (42) is continuously formed on the joint surface (12a) from an end portion of the first protrusion (40a) to the inside. Forming a plurality of ceramic molded bodies (10) including at least one ceramic molded body (10C) formed with:
A molded body joining step for joining the joint surfaces (12) of the plurality of ceramic molded bodies (10),
A method for producing a ceramic tube, comprising producing a ceramic tube having a hole formed by the through groove (42).
In the manufacturing method of the ceramic tube of Claim 4,
In the molded body manufacturing step, one third ceramic molded body (10C) having the first protrusion (40a) and a part of the joining surface (12d) are formed, and the through groove (42) is formed. A molded body producing step for producing at least one fourth ceramic molded body (10D) having a second protrusion (40b) that has not been formed;
In the molded body joining step, the first projection (40a) and the second projection (40b) are aligned with the joining surfaces (12c, 12d), respectively, and the third ceramic molded body (10C) and the A method for producing a ceramic tube, comprising joining a fourth ceramic molded body (10D).
In the manufacturing method of the ceramic tube of Claim 4,
The molded body manufacturing step includes a molded body manufacturing process of manufacturing at least two third ceramic molded bodies (10C) having the first protrusions (40a),
In the molded body joining step, the third ceramic molded body (10C) is joined so that the first protrusions (40a) are aligned with the joining surface (12c). Method.
The method for manufacturing a ceramic tube according to any one of claims 4 to 6,
The intersection of the outer periphery of the joint surface (12c) having the first protrusion (40a) and the axis (n2) of the through groove (42) in the first protrusion (40a) is defined as the intersection of the first protrusion (40a). As a base point (46),
The angle (θ) between the direction of the tangent (K1) at the base point (46) on the outer periphery of the joint surface (12c) and the axis (n2) of the through groove (42) is 30 ° to 60 °. A method for producing a ceramic tube characterized by the above.
The method for manufacturing a ceramic tube according to any one of claims 1 to 7,
The method for manufacturing a ceramic tube, wherein the joint surface (12) of the ceramic molded body (10) is parallel to a surface orthogonal to the axial direction.
A plurality of ceramic molded bodies (10) joined to each other, and a light emitting portion (34) that emits light inside, and electrodes provided on both sides of the light emitting portion (34) for introducing and sealing electrodes, respectively. In the ceramic tube (24C) for a high-intensity discharge lamp integrally having the introduction portion (36),
The light emitting part (34) is provided separately from the electrode introducing part (36), and has a protrusion (50) provided with a through hole (38c) for introducing a light emitting substance into the light emitting part (34). And
The protrusion (50) has an axis (n3) of the protrusion (50) directed toward the axis (m1) of the ceramic tube (24C), and the axis (n3) of the protrusion (50) and the ceramic tube (24C). ) Protrudes in a direction where the angle formed with the axis (m1) is 90 °,
The ceramic tube according to claim 1, wherein a protrusion amount of the protrusion (50) is in a range of 1/20 to 10/20 of a maximum diameter of the light emitting part (34).
A plurality of ceramic molded bodies (10) are joined to each other, and a light emitting section (34) that emits light inside, and an electrode introduction section that is provided on both sides of the light emitting section (34) and through which an electrode is inserted. (36) in a ceramic tube for a high-intensity discharge lamp,
The light emitting part (34) is provided separately from the electrode introducing part (36), and has a protrusion (50) provided with a through hole (38c) for introducing a light emitting substance into the light emitting part (34). And
When the relationship between the contour line (52) obtained by cutting the outer surface of the light emitting section (34) with a surface including the axis (n3) of the protrusion (50) and the axis (n3) is viewed,
The angle between the direction of the tangent line (K2) at the intersection (54) of the contour line (52) and the axis (n3) in the contour line (52) and the axis (n3) is 30 ° to 60 °. A ceramic tube characterized by being.