JPH09105200A - Fireproof ventilation structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a support metal fitting by using an aluminum alloy, etc., by installing an incombustible cubic expansion material in an air passage for ventilation and making the area of a heat-receiving section on the fire high-temperature side smaller than that of a heat-dissipating section. SOLUTION: An incombustible ceiling board 1 is borne by a support metal fitting 2 made of an aluminum alloy as a low molten metal, and an air passage 6 for ventilation is formed between the support section 2a of the support metal fitting 2 and a finished wall 4. An incombustible cubic expansion material 7 being expanded by heat and closing the air passage 6 is installed into the ventilation passage 6 on the rear of the support section 2a. In the constitution, the area of a heat-receiving section on the fire high-temperature side of the underside of the support section 2a is made smaller than that of a heat-dissipating section consisting of the upright section 2b, horizontal support piece 2c, mounting piece 2d, etc., of the support metal fitting 2. It is desirable that the area of the heat-dissipating section is made approximately double or more than that of the heat-receiving section. Accordingly, the support metal fitting 2 exposed on the fire high-temperature side can be formed of the aluminum alloy, etc., and this structure can be made advantageous in surfaces by dimensional accuracy, appearance, cost, secondary working, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fireproof ventilation structure for ventilation of an attic of a building or the like, and in particular, a support fitting for a nonflammable ceiling plate can be constructed by using a low melting metal such as aluminum. It is related to the fire protection ventilation structure.

[0002]

2. Description of the Related Art As a conventional fireproof ventilation structure of this type,
8 (A), (B), (C) developed by the applicant of this patent
Techniques such as a fireproof ventilation structure (Japanese Patent Application No. 4-247154) shown in FIG. 9 or a fireproof ventilation structure (Japanese Patent Application No. 4-247155) shown in FIGS. 9A, 9B and 9C are known. .

That is, in the known technique shown in FIGS. 8A, 8B, and 8C, a nonflammable ceiling plate 51 is made of steel having a U-shaped cross section.
It is mounted and fixed to a wall surface 53 while being supported by a support metal fitting 52 formed of a high melting point metal such as stainless steel, and ventilation holes 54 and 55 are formed in an upper surface 52a and a lower surface 52b of the support metal fitting 52, respectively, and air on the ceiling side is provided. After entering the ventilation air passage 56 in the support fitting 52 from the ventilation hole 54 of the lower surface 52b, the upper surface 5
The structure is such that it is discharged from the ventilation hole 55 of 2a. In addition, a non-combustible volume expansion material 57 that expands due to heat is provided at a predetermined position in the ventilation air passage 56, and the non-combustible volume expansion material 57 is expanded at the time of fire or the like to expand the ventilation air passage
It is a technology that allows 6 to be completely closed and shut off.

Further, in the known technique shown in FIGS. 9A, 9B and 9C, a support metal fitting 58 which is different in shape from the support metal fitting 52 and similarly formed of steel, stainless steel or the like is used. A non-combustible volume expansion material 57 is provided in the ventilation air passage 56 that supports the non-combustible material 57 and is formed between the L-shaped substrate portion 58a of the support fitting 58 and the plate support portion 58b having an inverted U-shaped cross section. It has a different structure.

[0005]

Since the temperature of a flame or the like at the time of a fire reaches 850 to 900 ° C., in order to sufficiently withstand this temperature, the temperature of 1200 ° C. It was necessary to support the noncombustible ceiling board by using supporting brackets 52 and 58 made of various steel or stainless steel.

However, the above-mentioned conventional support fittings 52, 5 are used.
When 8 was made of a metal such as steel or stainless steel having a high temperature melting point, there were the following major problems. That is, with a focus on manufacturing costs, a thin plate is used to support the metal fitting 5.
In the case of forming Nos. 2 and 58, the shape accuracy was poor and there were deformations, etc., and there was a problem in terms of appearance. Therefore, in order to solve this problem, a cover material composed of a separate component or the like is used, but there is a problem that the structure is complicated and the assembling work is complicated.

Further, when a thick plate is used to improve the defects of the thin plate, the shape accuracy is improved, but there is a problem that the processing is difficult and the cost is increased and the whole is heavy. Further, these support fittings 52 and 58 require secondary processing such as cutting into a predetermined size at a construction site for use, but the support fittings 52 and 58 made of steel or stainless steel are thin plates. However, there is a problem that it is difficult to carry out secondary processing, not limited to thick plates. There is also a problem that commonly used steel is easily rusted.

The present invention is a new technique developed in view of the above-mentioned many problems of the prior art. Particularly, it has a good dimensional accuracy, a beautiful appearance, is resistant to rust, and can be mass-produced at low cost by extrusion molding or the like. A support metal fitting made of low-melting metal such as aluminum that can be manufactured and has good secondary workability.
The purpose of the present invention is to provide a completely new technology of fire protection ventilation structure that can support non-combustible ceiling panels.

[0009]

A fireproof ventilation structure according to the present invention is a technique that has fundamentally improved the above-mentioned conventional problems, and the gist of the first invention is to support a non-combustible ceiling plate as a support fitting. In a fireproof ventilation structure, which is configured to be provided with a non-combustible volume expandable material that is supported by a ventilation air passage in or around the support metal and that is expanded by heat in the ventilation air passage. When the supporting metal fitting is formed by using a low-melting metal and the position of the supporting metal fitting provided with the non-combustible volume expansion material is centered, the heat receiving part area on the high temperature side of the fire of the supporting metal fitting is reduced to the other area. This is a fireproof ventilation structure characterized by being configured to be smaller than the area of the heat radiation part on the temperature side.

The gist of the second invention of the fireproof ventilation structure is as follows.
The low-melting metal is an aluminum alloy, which is the fireproof ventilation structure of the first invention. The gist of the third invention is that the area of the heat radiating portion of the support fitting is about 2 times the area of the heat receiving portion.
It is the fireproof ventilation structure according to any one of the first invention and the second invention characterized in that it is more than double.

Further, the gist of the fourth invention of the fireproof ventilation structure is as follows.
It is the fire protection ventilation structure according to any one of the first to third inventions, characterized in that the heat dissipating portion of the support fitting is provided outside the ventilation air passage. The gist of the fifth invention is the fire protection ventilation structure according to any one of the first invention to the fourth invention, characterized in that the heat dissipating portion of the support fitting is provided with a heat dissipating fin.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In view of the above-mentioned many problems of the prior art, the inventors of the present invention can easily process without using steel and stainless steel, which have various problems, have good dimensional accuracy, and have a beautiful appearance. A support metal fitting that supports the non-combustible ceiling board along the ventilation air passage is configured by using a low-melting metal that is rust-resistant and can be mass-produced at low cost, for example, an aluminum alloy having a melting temperature of 640 to 655 ° C. After many years of research, it was 850-900 during a fire.
It was confirmed that even if the above-mentioned aluminum alloy whose melting temperature is lower than 0 ° C is used, it can be sufficiently used under certain conditions. The reason and the principle of the use thereof are as follows.

Generally, in order to melt a metal, it is necessary to place the metal in a temperature environment higher than the melting temperature to heat the metal. The melting mechanism generally receives heat from the surroundings, and reaches the melting temperature when it receives a mass and a specific heat and a heat amount corresponding to the product of the temperature difference between the initial temperature and the melting temperature.
For further melting, a heat quantity corresponding to the product of the mass and the latent heat of melting is required. Therefore, the relation between them is as follows.

Heat quantity until reaching melting temperature = mass × specific heat × temperature difference (melting temperature−initial temperature) (1), heat quantity for melting = mass × melting latent heat (2)

However, when a part of the metal is placed in a temperature environment higher than the melting temperature and another part is placed in a temperature environment lower than the melting temperature, the heat does not reach the melting temperature because heat flows from the higher side to the lower side. Things are well known.

The above-mentioned relationship is shown in FIG.
When the left piece 31a of the H-shaped metal fitting 31 is exposed to the high temperature section 32 side, the right piece 31b is exposed to the low temperature section 33 side, and the left and right pieces 31a and 31b are cut off by the heat insulating section 34,
The high heat of the left piece 31a exposed to the high temperature part 32 and heated,
In order to flow to the right piece 31b through the connection transmission piece 31c,
It is known that the temperature of the left piece 31a does not reach the temperature of the high temperature portion 32. Further, as shown in FIG. 1, it was also found that when the area of the left piece 31a was made smaller than the area of the right piece 31b, the temperature of the left piece 31a on the heat receiving side did not become higher.

Next, as shown in FIG. 2, a metal material 35 used as a support fitting for the ventilation air passage is erected in a partition shape between the heating side 36 and the heat radiating side 37, and the metal 3 is heated on the heating side 36.
5 to a high temperature ambient temperature 39a of 38 or higher,
When the low temperature ambient temperature 39b on the heat radiation side 37 is set to the melting temperature 38 or lower, the high temperature side metal temperature 39c on the surface of the metal material 35 becomes a temperature significantly lower than the melting point temperature 38, and the metal on the heat radiation side 37 is It has been found that the surface low temperature side metal temperature 39d of the material 35 is higher than the low temperature atmosphere temperature 39b.

Therefore, even if the support made of the metal material 35 is used within a high temperature where the temperature of the heating side 36 is higher than the metal melting point temperature 38, the support can be used without melting. It became clear.

However, even if the above conditions are met, (1) the heat conduction path is narrow, (2) the heat conduction path is long, and (3) the heat conductivity is small and heat is not generated. When heat transfer is insufficient, such as when it is difficult to flow, the metal on the heating side 36 may melt. When (4) the heat radiation area is small and the heat radiation amount is insufficient, (5) the low temperature side ambient temperature 3
It has been found that the metal on the heating side 36 may be melted even when the heat radiation is insufficient, such as when the heat radiation amount is insufficient and the heat radiation amount is high.

From the above, it was found that the following points should be taken into consideration when the support metal fittings are made of a low melting metal such as an aluminum alloy. That is, (1) a non-combustible volume expansion material is attached along the ventilation air passage of the support fitting, and when heat is applied, the air passage is closed by foaming to prevent heat from entering the inside. (2) The heat receiving part placed in a high temperature atmosphere is limited to a small range by foaming the noncombustible volume expansion material. (3) Combine the foamed non-combustible volume expansion material and the periphery of the metal object with a high heat insulating property (a material with a high specific heat is preferable) to suppress an increase in the internal (low temperature side) atmosphere temperature. (4) The area of the heat transfer portion is sufficient and sufficient to transfer the amount of heat received by the heat receiving portion limited to a small range. (5) The area of the heat radiating portion is sufficient and sufficient to radiate the amount of heat received by the heat receiving portion.

Next, the relationship between the area of the heat receiving portion on the heating side of the support fitting and the area of the heat radiating portion on the heat radiating side is clearly shown to satisfy the following relationship.

(A) Amount of heat received by the heat receiving part: Q1, ambient temperature of high temperature part: t1, temperature of metal desired to be suppressed in consideration of strength: t2, heat transmission coefficient for transmitting temperature from the surroundings to the metal: k
1, surface area of heat receiving part: S1 Q1 = k1 × S1 ×
(T1-t2).

(B) Heat conduction area: s1, heat conductivity: α
1, conduction length: L1, allowable temperature drop: t3

[0024]

(Equation 1)

(C) Heat dissipation area: S2, average temperature of low temperature part: t5, average metal temperature of low temperature part: t4, heat transmission coefficient for transmitting temperature from metal surface to surroundings: k2

[0026]

(Equation 2)

For simplicity, k1 = k2, and the heat conduction length is short and can be neglected. Therefore, the heat receiving portion area and the heat radiating portion area have the following relationship.

[0028]

(Equation 3)

Based on the above-mentioned relations and calculations, concretely determine the kind of metal used for the support metal fitting, the allowable temperature, the heat insulation state of the surroundings, the ambient temperature, the mounting method and the size of the support metal fitting. Can be done.

Next, the inventors of the present invention confirmed whether or not the above relations and mathematical formulas were satisfied based on a concrete test. That is, ventilation holes and passages communicating with the inside and outside are provided at the corners of the calcium silicate-based plate that are orthogonal to each other, and the melting temperature is 640 to 65.
The ventilation port and the passage are covered with a metal plate made of an aluminum alloy at 5 ° C, and a part of the covered metal plate is exposed to the inside to serve as a heat receiving portion, and the remaining metal plate is exposed to the outside to radiate heat. Configured as a part. When heat is further applied, the entrance of the passage is blocked and blocked by the noncombustible volume expansion material.

The temperature conditions on the high temperature side are set to JIS A1304.
According to the basic condition of the fire resistance test of 45 minutes, the allowable temperature target of the high temperature side metal was set to 540 ° C. In addition, the high temperature atmosphere temperature is 890 ° C, and the low temperature side atmosphere average temperature is 200.
℃, the high temperature part metal temperature is 540 ° C. (temperature difference from the high temperature part atmosphere temperature is 350 ° C.), and the low temperature side metal average temperature is 350 ° C. (temperature difference from the low temperature side atmosphere average temperature is 150 ° C.). As a result of trial calculation of the ratio of the heat receiving area on the high temperature side and the heat radiating area on the low temperature side of the metal plate covering the ventilation port and passage of
From S ₂ = S ₁ × (350/150) ≈2.34, it became clear that the heat radiating portion area needs to be 2.34 times the heat receiving portion area or more.

In consideration of all the above-mentioned relations, the present inventors have embodied the fireproof ventilation structure described below as an example, and will be described with reference to the drawings. That is, FIG. 3 (A), (B)
5 is a cross-sectional explanatory view of a main part of the fireproof ventilation structure of the first embodiment according to the present invention, FIG. 4 is a perspective explanatory view of the fireproof ventilation structure of FIG. 3, and FIG.
3 is a cross-sectional explanatory view showing the supporting metal fittings and the temperature around the metal fitting in the fire-proof ventilation structure of FIG. 3, FIG. 6 is a cross-sectional explanatory view of a main part of the fire-proof ventilation structure of the second embodiment, and FIG. 7 is of the third embodiment. It is a section explanatory view of the important section of fire prevention ventilation structure.

In FIGS. 3A, 3B and 4, 1
Is a non-combustible ceiling plate, and is attached to the wall plate 3 on the building skeleton side through the support fitting 2. The support fitting 2 used in the present invention is made of an aluminum alloy which is a low melting metal. The supporting metal fitting 2 has a supporting portion 2a having a substantially U-shaped cross section into which a side edge portion of the non-combustible plate 1 can be fitted, and a vertical rising portion which is continuously vertical to the upper edge of the U-shaped supporting portion 2a. A piece 2b is provided, and a horizontal support piece 2c is horizontally connected to the upper end of the rising piece 2b.
A mounting piece 2d is continuously provided in the vertical direction at the tip of c.

Reference numeral 4 denotes a finishing wall made of a non-combustible material, which is laminated on the side surface of the wall plate 3 on the building skeleton side.
The horizontal width of the horizontal support piece 2c of the support fitting 2 is formed larger than the horizontal width of the support portion 2a, and a large number of ventilation holes 5 are formed in parallel on the left side of the horizontal support piece 2c.
The right side portion of the horizontal support piece 2c is in contact with the upper edge of the finishing wall 4, and a ventilation air passage 6 is provided between the rear surface of the supporting portion 2a and the finishing wall 4. Has been done.

On the back surface of the support portion 2a, a noncombustible volume expansion material 7 which is expanded by heat along the ventilation air passage 6 is attached. This non-combustible volume expansion material 7
Has a property of expanding about 10 times when the temperature of hot air in the passage at the time of fire reaches 150 to 170 ° C. The composition and the like are already known from JP-B-63-132968 (fireproof composition), JP-B-3-235 (fireproof / fireproof coated mat) and the like.

In the fireproof ventilation structure according to the present invention, as described above, the nonflammable volume expansion material 7 is attached along the ventilation air passage 6 provided on the back surface of the support portion 2a of the support fitting 2, so that the outdoor side When a fire occurs and the hot air temperature passing through the ventilation air passage 6 reaches about 150 ° C or higher, the noncombustible volume expansion material 7
Foams and completely closes the ventilation air passage 6,
This can prevent hot air from entering the back of the hut.

As described above, assuming that the ventilation air passage 6 is closed by the non-combustible volume expandable material 7 as shown in FIG. It can be divided into a heat receiving part X on the high temperature side of the fire and a heat radiating part Y on the low temperature side with the attached position as the center. Therefore, in the case of the embodiment shown in FIGS. 3 and 4, the lower surface piece of the supporting portion 2a of the support fitting 2 becomes the heat receiving portion X, and the upper surface piece of the supporting portion 2a, the rising piece 2b, and the horizontal supporting piece 2 are formed.
c and the attachment piece 2d are the heat dissipation portion Y. The area of the heat radiating portion Y with respect to the heat receiving portion X in the embodiment is about 6.8.
It is doubled.

As shown in FIG. 5, the following data could be obtained by conducting an experiment on the fireproof ventilation structure of the present invention having the above-mentioned structure. That is, the heating temperature of the fireproof test according to JIS A1304 is designed to increase with time,
It will be explained with data for 10 minutes from 36 minutes to 45 minutes, which is a stable heating state of high temperature after being sufficiently heated. First, the non-combustible ceiling plate 1 and the heat-foamed non-combustible volume expansion material 7 are used as a sakai, and the external high temperature side 8 becomes high temperature due to a fire.
And the internal low temperature side 9 can be divided.

The area of the heat receiving portion X of the support fitting 2 exposed on the external high temperature side 8 was set to 1, and the area of the heat radiating portion Y of the support fitting 2 exposed on the other internal low temperature side 9 was a ratio. Further, since the area of the heat radiating portion Y exposed on the internal low temperature side 9 is large and the ambient temperature is not uniform, the calculation was performed separately for four portions of A portion, B portion, C portion, and D portion. The temperature data from the experiment are shown in the following table.

[0040]

[Table 1]

Based on the temperature data obtained by the above experiment, k
The following table summarizes the product of the area and the temperature difference between the heat receiving portion X and the heat radiating portion Y when 1 = k2.

[0042]

[Table 2]

By summing up the above experimental results, the following was found. That is, (1) It was judged that the heat radiation side area Y was initially 6.8 times the heat receiving section area X, but in the experimental results, there was almost no heat radiation in the A section, and conversely, in the B section, the heat receiving section. Has become. The effective area for heat dissipation is C
Part and D part. (2) Since the temperature difference on the heat receiving side is larger than the assumed temperature difference, the amount of heat received is large. This is natural because it has not reached the allowable metal temperature of 540 ° C.
(3) The following features were seen on the heat dissipation part side. (3-
1) In part B, the ambient temperature is higher than the metal temperature and heating is performed in the opposite manner to heat radiation. This is because the part B is surrounded by the surroundings except the opening of the air passage, and the internal air pressure is set lower than the external air pressure, so that high temperature air passes through the inside of the foam material and accumulates. It is thought that it will be in a state of being stuck.
(3-2) The temperature difference between the metal and the atmosphere is smaller than the hypothesis, probably because the area of the other heat dissipation portion is larger than the assumption. (4) Since the amount of heat received exceeds the amount of heat released, the temperature of the metal on the heating side rises further, but if the temperature rises to the allowable temperature and the difference from the ambient temperature becomes smaller, the amount of heat received will reach a ceiling and It is easily assumed that the temperature rise will stop at the time of equilibrium.

From the results of this test, generally, the heating conditions of the fireproof test according to JIS A1304 assuming a fire in a house 45
It has been found that even with heating for a minute, the support metal fittings made of aluminum alloy can sufficiently function without being broken and melting such that the fireproof performance is lost.

In order to avoid the atmosphere shown in the above experimental results, in which the heat is accumulated in the heat radiating portion side at the low temperature, especially in the portion B, the inventors of the present invention have shown the fire preventive ventilation structure of the second embodiment as shown in FIG. Also developed. That is, the second embodiment shown in FIG. 6 uses the support metal fitting 10 having a structure in which the horizontal support piece 2c and the mounting piece 2d of the support metal fitting 2 as described above are completely eliminated, and the rising piece 2b is extended upward as it is. Fireproof ventilation structure. In the case of this embodiment, heat is not accumulated on the heat radiating portion side, so that the heat dissipation by the support fitting 10 can be smoothly performed.

Further, the inventors of the present invention, as shown in FIG.
When a structure for increasing the heat radiation area and improving the heat radiation efficiency is studied in a place where the space at the heat radiation portion side with a low internal temperature is small, etc., a heat radiation fin 12 is provided on the heat radiation portion side as shown in the support fitting 11 of FIG. It has been invented that the purpose can be sufficiently achieved by integrally mounting. 1 in the figure
3 is a wilderness and 14 is a rafter.

[0047]

Since the fireproof ventilation structure according to the present invention has the above-mentioned structure, it has the following great effects.

(1) The support fitting exposed on the high temperature side of the fire can be made of a low melting point metal such as an aluminum alloy. (2) Therefore, it is possible to form a support fitting having a good dimensional accuracy and a beautiful appearance. (3) Since extrusion molding is possible, mass production can be carried out at a lower cost than in press processing or roll processing. (4) Rust resistant and durable for many years. (5) It has excellent secondary workability and can facilitate work at the construction site.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional explanatory view showing a principle that heat of a metal exposed in a high temperature portion flows to a metal side exposed in a low temperature portion and is radiated.

FIG. 2 is an explanatory diagram showing changes in surface temperature when a single metal plate is exposed on a heating side and a heat radiating side, respectively.

3 (A) and 3 (B) are cross-sectional explanatory views of the essential parts of the fire protection ventilation structure of the first embodiment according to the present invention.

FIG. 4 is a perspective explanatory view of the fire protection ventilation structure of FIG.

5 is a cross-sectional explanatory view showing the temperature of the support fitting and its surroundings in the fireproof ventilation structure of FIG.

FIG. 6 is a cross-sectional explanatory view of the essential parts of the fire protection ventilation structure of the second embodiment.

FIG. 7 is an explanatory cross-sectional view of the main parts of the fire protection ventilation structure of the third embodiment.

8 (A), (B) and (C) are side sectional explanatory views showing a conventional fire protection ventilation structure.

9 (A), (B) and (C) are side sectional explanatory views showing another conventional fire protection ventilation structure.

[Explanation of symbols]

1 non-combustible ceiling board 2 support metal fitting 2a support part 2b rising part 2c horizontal support piece 2d mounting piece 3 wall plate 4 finishing wall 5 ventilation hole 6 ventilation air passage 7 non-combustible volume expansion material 8 external high temperature side 9 internal low temperature side 10 Supporting bracket 11 Supporting bracket 12 Radiating fin 13 Field rim 14 Tatari 31 H-shaped bracket 31a Left piece 31b Right piece 31c Transmission piece 32 High temperature part 33 Low temperature part 34 Insulation part 35 Metal material 36 Heating side 37 Radiating side 38 Melting point temperature 39a High temperature Ambient temperature 39b Low temperature ambient temperature 39c High temperature side metal temperature 39d Low temperature side metal temperature 51 Non-combustible ceiling plate 52 Support metal fitting 53 Wall surface 54,55 Ventilation hole 56 Ventilation air passage 57 Non-combustible volume expansion material 58 Support metal fitting

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Daisuke Kawana 2-20-5 Shimotani, Taito-ku, Tokyo Within Nippon Kagaku Kogyo Co., Ltd.

Claims (5)

[Claims] 1. A non-combustible ceiling plate is supported by a support fitting, and a ventilation air passage is provided in or around the support fitting and a non-combustible volume expansion material that expands by heat is provided in the ventilation air passage. In the fire protection ventilation structure configured to be provided in the above, when the supporting metal fitting is formed by using a low-melting metal, and the center of the supporting metal fitting where the non-combustible volume expansion material is provided is A fire prevention ventilation structure characterized in that the heat receiving portion area on the high temperature side of the fire is smaller than the heat radiating portion area on the other low temperature side. 2. The fire protection ventilation structure according to claim 1, wherein the low-melting metal is an aluminum alloy. 3. The fireproof ventilation structure according to claim 1, wherein the area of the heat radiating portion of the support fitting is about twice or more the area of the heat receiving portion. 4. The fire protection ventilation structure according to claim 1, wherein the heat dissipating portion of the support fitting is provided outside the ventilation air passage. 5. The fire protection ventilation structure according to claim 1, wherein a heat radiation fin is provided on a heat radiation portion of the support fitting.