JP3153445B2 - Method of manufacturing a combustion plate for a surface combustion burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a combustion plate for a surface combustion burner used in various combustion devices such as a water heater.

[0002]

2. Description of the Related Art Conventionally, as a surface combustion burner used for various combustion devices such as a water heater, a combustion plate is attached so as to cover one surface of a gas burner main body, and gas ejected from the combustion plate is used for the combustion plate. There is known a configuration in which combustion occurs on the surface of an object.

In recent years, it has been studied to use a compact obtained by laminating silicon carbide-coated Si—CO—based silicon carbide fibers on the combustion plate. As the silicon carbide fibers, SiC _1.20 O _0.42 SiC-O type silicon carbide fiber having a composition of (Nippon Carbon Co., Ltd., Nicalon (trademark)) is known. This fiber is a flexible continuous filament yarn which is susceptible to pyrolysis itself, but which can be chemically vapor deposited (abbreviated as CVD) or chemical vapor infiltration (Chemical VaporInf).
illumination, abbreviated as CVI method)
By coating the surface with silicon carbide, excellent heat resistance suitable for the combustion plate can be obtained.

Si—C coated with silicon carbide
When a molded body obtained by laminating -O-based silicon carbide fibers is used for the combustion plate, gas is ejected from gaps between the fibers, so that the entire surface of the combustion plate can be a combustion surface. Depending on the state of lamination of the fibers in the above, it is desired to further provide a flame port that penetrates the combustion plate, and to mainly eject and burn gas from the flame port.

However, when the surface of the Si-CO-based silicon carbide fiber is coated with silicon carbide, the silicon carbide fiber tends to harden and increase rigidity. When it is attempted to form the flame port by penetrating a drilling member such as a drill or a punch into a molded product obtained by laminating fibers, the fiber is moved from the axis of the flame port formed at the time of penetration of the drilling member to the outer circumferential direction. However, when the perforated member is pulled out, the once displaced fiber swells from the outer peripheral side of the flame port formed by its rigidity into the flame port, so that a flame port having a desired diameter is formed. There is a disadvantage that it is difficult to be performed.

[0006] The silicon carbide fibers having a surface coated with silicon carbide tend to have high rigidity and tend to be brittle, so that a molded article obtained by laminating such silicon carbide fibers has the above-mentioned properties. When the flame port is formed as described above, the shape of the formed flame port is easily collapsed, and in a portion where the flame port is densely arranged, when the piercing member collides with the surface of the molded body. There is an inconvenience that the impact may cause the molded body to break.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned disadvantages.
It is an object of the present invention to provide a method of manufacturing a combustion plate for a surface combustion burner, which can easily manufacture a combustion plate in which a molded body on which a -CO-based silicon carbide fiber is laminated is provided with a flame port having a predetermined shape. And

[0008]

In order to achieve the above object, a method of manufacturing a combustion plate for a surface combustion burner according to the present invention is provided so as to cover one surface of a gas burner body of the surface combustion burner. Si coated with silicon carbide
A method for manufacturing a combustion plate, comprising: forming a plurality of flame ports penetrating a molded body on which a -CO-based silicon carbide fiber is laminated, wherein the Si-CO-based silicon carbide fiber is dispersed. A male mold having a protrusion forming the flame outlet is immersed in the liquid, and the fibers are taken out with the male mold and laminated to a predetermined thickness, and a hole corresponding to the protrusion is formed. The molded body having a predetermined shape is formed by compressing the laminated fiber between the male mold and the female mold so that the female mold provided has the protrusion fitted into the hole. Forming a molded body, and removing the male and female molds from the molded body and removing the liquid from the molded body, and forming a flame port in the trace of the protrusion, The formed body having the flame outlet is opposed to an air flow containing a raw material gas for reaction under high temperature and low pressure, and silicon carbide is formed on the surface of the fiber. Characterized by comprising a coating step of coating with silicon carbide film by precipitating.

In the method for producing a combustion plate for a surface combustion burner according to the present invention, the liquid is water or starch paste,
1 selected from ceramic adhesive or synthetic resin adhesive
Different binder solutions are used. When the liquid is water, in the flame port forming step, the molded body is dried to remove water from the molded body. Further, when the liquid is the binder solution, in the flame port forming step, the molded body is incinerated at a temperature within a range where the Si-CO-based silicon carbide fiber is not thermally deteriorated. Remove the binder solution.

[0010]

According to the manufacturing method of the present invention, first, Si-C-
O-type silicon carbide fibers are dispersed in a liquid, and the male mold is immersed in the liquid to extract the fibers, whereby the fibers adhere along the outer surface shape of the male mold, and Laminated to thickness. Next, the laminated fiber is inserted into the male mold and the female mold so that the male mold is fitted into the female mold having a hole corresponding to the protrusion. When compressed, the fibers adhere to the outer shape of the male mold, so that the inner surface shape is shaped along the outer shape of the protrusion at the mark of the male protrusion. Is formed, and a molded article in which the fibers are laminated is obtained.
Next, the male mold and the female mold are removed from the molded body, and the liquid is removed from the molded body to obtain a molded body composed of only the fibers.

Next, silicon carbide is precipitated on the surface of the fiber by facing the molded body having the flame port formed therein at a high temperature and a low pressure to an air current containing a raw material gas for reaction, and the surface of the fiber is coated with a silicon carbide film. By coating, a combustion plate having a flame port having a predetermined shape is obtained.

At this time, the liquid may be simple water as long as the liquid adheres the fibers to the male mold.
By using a binder solution such as starch paste, a ceramic adhesive or a synthetic resin adhesive, the fiber adheres to the male mold, and the flame outlet having an inner surface shape shaped along the outer surface shape of the protrusion is formed. In addition to being easily formed, the porosity required when the molded body is used as a combustion plate is easily adjusted.

[0013] When the liquid is water, the water is removed by drying the molded body, and when the liquid is the binder solution, the molded body is dried with the Si-CO-based silicon carbide fiber. The binder solution is removed by incineration at a temperature within a range that does not cause thermal deterioration, and a molded body consisting of only the fibers is obtained.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a method of manufacturing a combustion plate for a surface combustion burner according to the present invention. FIG. 1 is a perspective view showing an example of the configuration of a surface combustion burner using the combustion plate of the present invention, FIG. 2 is an end view taken along the line II-II of FIG. 1, and FIGS. FIG. 6 is an explanatory sectional view showing a method, and FIG.
Is an explanatory sectional view showing a method of coating the compact shown in FIG. 5 with silicon carbide, and FIG. 7 is an explanatory sectional view showing a method of manufacturing a combustion plate of another embodiment.

The surface combustion burner of the present embodiment is used in a rear exhaust type combustion apparatus for cooking grilled fish such as grilled fish, which is generally called a grill, and is mounted on a ceiling of a combustion chamber in which a material to be burned is placed. And a burner for the upper fire, which is disposed so as to face the above-mentioned fired material. As shown in FIG. 1, the surface combustion burner 1 of the present embodiment is a flat box-type having a gas mixing pipe 2 for mixing a gas ejected from a nozzle (not shown) and primary air to supply a gas mixture. Si coated with silicon carbide so as to cover one surface of the gas burner main body 3 of FIG.
Combustion plate 4 formed by laminating CO-based silicon carbide fibers
However, at the time of the coating, the surface facing the airflow containing the raw material gas for reaction is attached as a combustion surface. In the surface combustion burner 1, as shown in FIG. 2, a gap between the gas burner main body 3 and the combustion plate 4 forms a gas passage 5 for flowing a gas mixture supplied from a gas mixing pipe 2. The combustion plate 4 is provided with a large number of small-diameter flame ports 6 that penetrate the combustion plate 4 to eject and burn the gas mixture.

The diameter of the flame port 6 is 0.8 to 0.8 depending on the gas type.
It is appropriately selected within a range of up to 1.2 mm. In the surface combustion burner 1 of the present embodiment, a main combustion flame is mainly formed by the combustion of the gas mixture ejected from the flame port 6, and
Even in the portion where the flame opening 6 is not provided, a small flame is formed by the secondary combustion of the gas mixture ejected from the gap between the fibers.

Next, a method of manufacturing the combustion plate 4 of this embodiment will be described with reference to FIGS.

In the manufacturing method of the present embodiment, first, as shown in FIG. 3, the Si—CO—O-based silicon carbide fibers 33 are dispersed in water 32 or a binder solution liquid 32 contained in a storage tank 31. . The Si-CO-based silicon carbide fibers 33 are:
With a diameter of 9 to 25 μm and a density of 2.0 to 3.0 g / cm ³ ,
Dispersed in liquid 32. The storage tank 31 is provided with a male mold 35 having a columnar protrusion 34 so as to be able to move up and down by a liquid-tight cylinder 36. Above the storage tank 31, a peripheral portion of the male mold 35 is provided. Outer frame 37 attached along
And a female mold 39 having a hole 38 corresponding to the projection 34.

Next, the Si-CO-based silicon carbide fiber 3
A male mold 35 having a protrusion 34 forming the flame port 6 is immersed in a liquid 32 in which the male mold 35 is dispersed, and the male mold 35 is swung up and down by a cylinder 36, whereby paper is formed by the male mold 35. As described above, the Si-CO-based silicon carbide fiber 33
And adhered along the outer surface shape of the male mold 35 and laminated to a predetermined thickness. Then, as indicated by the imaginary line in FIG. 3, the male mold 35 is raised by the cylinder 36 together with the laminated Si—CO-based silicon carbide fibers 33 (not shown).

Then, as shown in FIG.
An outer frame 37 provided above 1 is attached to male mold 35, and the shape of Si—CO—based silicon carbide fibers 33 laminated on male mold 35 is defined according to the shape of outer frame 37. . Next, the projections 34 of the male mold 35 are fitted into the holes 38 of the female mold 39, and the Si—CO—based silicon carbide fibers 33 stacked on the male mold 35 are combined with the male mold 35 and the female mold 39. The compact 40 is obtained by compressing between the two.

Next, as shown in FIG. 5, when the male mold 35, the outer frame 37 and the female mold 39 are released from the molded body 40, the Si-C
-O-based silicon carbide fiber 33 is a male type 3 using liquid 32 as a medium.
5 is attached along the outer surface shape of the projection 34 provided in 5, so that the flame hole 6 whose inner surface is shaped into a cylindrical shape along the columnar projection 34 is formed in the trace of the projection 34. Is done. The liquid 32 is made of starch paste, ceramic adhesive,
Synthetic resin adhesive [for example, polyvinyl alcohol (PV
A)] or the like, so that Si—C
The —O-based silicon carbide fibers 33 easily adhere along the outer surface shape of the columnar projections 34, and the porosity required for the combustion plate 4 is easily adjusted.

After the male mold 35, the outer frame 37 and the female mold 39 are released from the molded body 40 as described above, the liquid 32 is removed from the molded body 40 in which the flame opening 6 is formed. The removal of the liquid 32 is performed by naturally drying the molded body 40 when the liquid 32 is water. When the liquid 32 is the binder solution, the molding is performed by incinerating the molded body 40 at a temperature within a range where the Si-CO-based silicon carbide fibers 33 are not thermally deteriorated.

Next, the molded body 40 on which the flame port 6 is formed
Is coated with silicon carbide by a CVD method,
A SiC coating is further formed on the surface of the CO-based silicon carbide fiber. In the CVD method, as shown in FIG. 6, the compact 40 is horizontally arranged in a CVD furnace under high temperature and low pressure, and raw material gases for reaction (SiCl ₄ and CH ₄ ) are supplied from above the compact 40 vertically. This is performed by flowing down an air flow 41 of a carrier gas (H ₂ ) containing the gas. The CVD furnace is 1200-1
While heated to a temperature in the range of 300 ° C.,
The pressure is reduced to a pressure in the range of 0 Torr.

When the treatment is performed under the high temperature and low pressure conditions for 5 to 30 minutes, the surface 4 of the molded body 40 on the side facing the airflow 41 is formed.
0a, the surface of the Si-CO-based silicon carbide fiber is 0.1
The surface of the fiber is thicker than the surface 40a because the surface 40b on the opposite side is coated with a SiC film (not shown) having a thickness of .about.0.7 .mu.m and the raw material gas for reaction increases on the opposite surface 40b under the influence of gravity. Coated with a SiC coating (not shown). The Si-CO-based silicon carbide fibers tend to have lower heat resistance as the thickness of the SiC film formed on the surface thereof increases, but the thickness of the SiC film is 0.1 to 0.7.
The surface 40a in the range of μm exhibits heat resistance at a temperature of 1300 to 1400 ° C., and the surface 40b having a SiC coating thickness of more than 0.7 μm exhibits heat resistance up to a temperature of about 800 ° C. Is obtained.

In this embodiment, after the Si-CO-based silicon carbide fibers 33 are taken out by the male mold 35 and laminated to a predetermined thickness, the outer frame 37 is attached to the male mold 35 and the male mold 35 is attached. Although the shape of the Si-CO-based silicon carbide fibers 33 laminated on the upper surface 35 is defined, as shown in FIG. Immersion in Si-CO
The base silicon carbide fiber 33 may be removed.

Although the male mold 35 used in the above embodiment may be made of metal, it is detachable from the cylinder 36 by using a combustible material such as paper, and the molded body 40 is detached from the outer frame 37.
After the female mold 39 is released from the mold, the male mold 35 may be removed together with the molded body 40 by incineration at a temperature at which the Si-CO-based silicon carbide fibers do not thermally deteriorate. Male type 3
If the mold 5 is made of metal, the protrusion 34 may deform the shape of the flame port 6 when mechanically demolding from the molded body 40, but as described above, the male mold 35 made of a flammable material is used. When burning is to be removed by incineration, since no mechanical force acts on the molded body 40, the shape of the flame port 6 is not deformed, and the flame port 6 having excellent dimensional accuracy is formed at the mark of the projection 34. Can be. Also, at this time, the molded body 40 is dried and the liquid 32 is removed simultaneously with the incineration of the male mold 35, which is convenient.

In the above embodiment, the coating of the molded body 40 is performed by the CVD method, but may be performed by the CVI method. Furthermore, in the above-described embodiment, the surface combustion burner used in the rear-exhaust type combustion device for cooking grilled food is described. However, the surface combustion burner of the present invention is not limited to this. It can be used for combustion equipment.

[0028]

As is apparent from the above, according to the method of manufacturing a combustion plate for a surface combustion burner of the present invention,
Easily manufacture a combustion plate provided with a flame hole of a predetermined shape in the molded body without forming a flame hole with a perforated member in a molded body in which Si-CO-based silicon carbide fibers coated with silicon carbide are laminated. can do.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a surface combustion burner according to an embodiment.

FIG. 2 is an end view taken along line II-II of FIG.

FIG. 3 is an explanatory sectional view showing a method of manufacturing the surface combustion burner according to the embodiment.

FIG. 4 is an explanatory cross-sectional view illustrating a method of manufacturing the surface combustion burner of the present embodiment.

FIG. 5 is an explanatory sectional view showing the method for manufacturing the surface combustion burner according to the embodiment.

FIG. 6 is an explanatory sectional view showing a method of coating the compact shown in FIG. 5 with silicon carbide.

FIG. 7 is an explanatory sectional view showing a method of manufacturing a surface combustion burner according to another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Surface burning burner, 4 ... Burning plate, 6 ... Flame port, 32 ... Water or binder solution, 33 ... Si-
CO-based silicon carbide fiber, 34: protrusion, 35: male, 38: hole, 39: female, 40: molded body,
41 ... A gas stream containing a raw material gas for reaction.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kazuto Inoue 2-26 Fukuzumi-cho, Nakagawa-ku, Nagoya-shi, Aichi Rinnai Co., Ltd. (56) References JP-A-52-7037 (JP, A) JP-A-57 JP-A-129313 (JP, A) JP-A-60-99918 (JP, A) JP-A-63-207915 (JP, A) JP-A-4-335910 (JP, A) JP-A-8-334216 (JP, A) (58) Field surveyed (Int.Cl. ⁷ , DB name) F23D 14/12-14/18

Claims (4)

(57) [Claims] 1. A molded body in which Si-CO-based silicon carbide fibers coated with silicon carbide are attached so as to cover one surface of a gas burner body of a surface combustion burner. What is claimed is: 1. A method for manufacturing a combustion plate comprising a plurality of flame ports penetrating, comprising: a male mold having a projection forming the flame port in a liquid in which Si-CO-based silicon carbide fibers are dispersed. Dipped, the fibers are taken out with the male mold, laminated to a predetermined thickness, and a female mold having a hole corresponding to the protrusion is so fitted that the protrusion is fitted into the hole. Forming a molded body having a predetermined shape by compressing the laminated fibers between the male mold and the female mold; and forming the male mold and the female mold from the molded body. A flame that removes and removes the liquid from the molded body to form the flame opening at the mark of the protrusion A forming step, and a coating step of coating the formed body on which the flame port is formed with a silicon carbide film by causing silicon carbide to precipitate on the fiber surface while facing a gas flow containing a raw material gas for reaction under high temperature and low pressure. A method for producing a combustion plate for a surface combustion burner, comprising: 2. The method according to claim 1, wherein the liquid is water or one kind of binder solution selected from starch paste, ceramic adhesive and synthetic resin adhesive. . 3. The surface combustion burner according to claim 2, wherein when the liquid is water, in the flame port forming step, the molded body is dried to remove water from the molded body. Of manufacturing a combustion plate for use. 4. When the liquid is the binder solution, in the flame port forming step, the molded body is
The method for producing a combustion plate for a surface combustion burner according to claim 2, wherein the binder solution is removed from the molded body by incineration at a temperature within a range where the -CO-based silicon carbide fiber does not thermally deteriorate.