JP2014039357A - Fire-protection structure for outlet box and construction method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fire-protection structure for an outlet box that enables construction and inspection of fire-protection to be easily performed even after the outlet box is secured to a wall, and has excellent fire-resistant properties.SOLUTION: In a fire-protection structure for an outlet box which is installed on a wall having a through-hole so as to cover the through-hole, the outlet box has a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate, the outlet box is installed on the wall so that the opening portion side thereof faces to the wall side and a gap is formed between the wall and the outlet box, an electric wire cable group is inserted through an insertion hole formed in at least one of the back plate and the side plate of the outlet box, a first thermal-expansion type fire-resisting seat is inserted into the back plate side in the outlet box, and a second thermal-expansion type fire-resisting seat is installed on the inner periphery of the through-hole of the wall.

Description

  The present invention relates to a fire prevention structure for an outlet box used for indoor wiring and a construction method thereof.

Many outlets and switches installed inside the walls of buildings such as hollow walls contain plastic parts, so when a fire breaks out, these outlets and switches melt and deform, and the flame of the fire is May penetrate the inside of the wall.
When a fire flame enters the inside of a wall such as a hollow wall, there is a problem that the fire spreads through an electric cable connected to an outlet or a switch.
In order to cope with this problem, there has been proposed a fire prevention structure in which an outlet box is provided on the back of an outlet, a switch, or the like provided in a room, that is, inside a wall such as a hollow wall.

FIG. 17 is a schematic cross-sectional view for explaining a fire prevention structure of a first conventional outlet box.
A through hole is provided in the walls 40 and 40 forming the hollow wall, and the outlet box 1 is installed so as to cover the through hole from the inside of the walls 40 and 40. The outlet box 1 has a metal box shape having an opening. The outlet box 1 attached to the stud with a metal fitting or the like is installed inside the walls 40 and 40 in a state where the opening of the outlet box 1 faces the through hole of the walls 40 and 40.
An insertion hole is provided in the upper surface of the outlet box 1, and the electric cables 50 are inserted through the insertion hole. A fire spread prevention portion 21 made of a thermally expandable resin composition is provided outside the outlet box 1 so as to be in close contact with the outer periphery of the electric cables 50. The fire spread prevention portion 21 is exposed inside the outlet box 1 and closes the insertion hole of the outlet box 1 and the electric cables 50.
The ends of the electric cables 50 are connected to a wiring terminal 74. Further, a holding frame 73 holding the wiring terminal 74 is attached to the walls 40 and 40.
According to the first conventional outlet box fire prevention structure, it is said that the fire spread can be prevented even when the outlet box is exposed to a flame such as a fire (Patent Document 1).

However, as is clear from FIG. 17, after the outlet box 1 is installed inside the walls 40, 40, the outlet box 1 closes the through hole of the wall 40, so It is difficult to install the fire spread prevention part 21 with respect to the electric cables 50 from the outside.
For this reason, it is very difficult to install the outlet box 1 inside the walls 40 and 40 unless the cable 50 is inserted into the outlet box 1 and the fire spread prevention portion 21 is installed. Therefore, depending on the level of proficiency of the installer, there are problems that the construction time is delayed or that the finishing accuracy is deficient.
Further, after the outlet box 1 is installed inside the walls 40, 40, it is inspected from the outside of the walls 40, 40 whether there is a defect in the fire prevention structure of the first conventional outlet box installed. There was also a problem that was difficult to do.

FIG. 18 is a schematic cross-sectional view for explaining a fire prevention structure of a second conventional outlet box.
The second conventional outlet box fire prevention structure has a tubular structure when the electric cables 50 are fixed to the insertion hole of the outlet box 1 as compared to the first conventional outlet box fire prevention structure. The point which uses the cylindrical fixture 60 and the cylindrical fixture 61 is different.
A cylindrical fixture 60 is fixed to the electric cables 50 with a heat-resistant adhesive or the like, a cylindrical fixed receiver 61 is fixed to the insertion hole of the outlet box 1, and the cylindrical fixture 60 and the cylindrical fixed receiver are fixed. By fitting 61, the electric cables 50 can be fixed in the insertion hole of the outlet box 1.
In addition, the second conventional outlet box fire prevention structure has a gap between the tubular fixed receiver 61 and the electric cables 50 as compared with the first conventional outlet box fire prevention structure. The gap between the outlet box 1 and the wall 41 is closed with a heat-resistant putty 80, and the thermally expandable refractory sheet 20 is inserted into the outlet box 1, and further, a cylindrical tubular fixture 60 and a tubular fixed receiver. The difference is that the periphery of the tool 61 is wound by a thermally expandable refractory sheet 81.
According to this second conventional outlet box fire-protection structure, more reliable fire-proof performance can be secured (Patent Document 2).

However, even in the case of the second conventional outlet box fire prevention structure, after the outlet box is installed on the wall 41, the clearance between the outlet box 1 and the wall 41 is formed with a heat-resistant putty 80 from the outside of the wall 41. There was a problem that it was difficult to block.
In addition, after the outlet box 1 is installed inside the wall 41, the connection state between the cylindrical fixture 60 and the cylindrical fixture 61 cannot be observed from the outside of the wall 41. There remains a problem that it is difficult to inspect from the outside of the wall 41 whether there is a defect in the fire prevention structure of the conventional outlet box.

JP 2009-055697 A JP 2011-193717 A

Furthermore, as a result of repeated studies by the present inventors, it was discovered that there are the following problems.
When the fire prevention structure of the second conventional outlet box described above is exposed to heat such as a fire, the cylindrical fixture 60 and the cylindrical fixture 61 are melted, burned, etc., and the cylindrical fixture is fixed. The heat-resistant putty 80 installed in the receiver 61 may hang down inside the outlet box 1 along the electric cables 50.
When the heat-resistant putty 80 is inside the outlet box 1, free expansion of the heat-expandable fireproof sheet 20 inserted into the outlet box 1 is prevented.
As a result, the inside of the outlet box 1 is not completely closed by the expansion residue due to the heat-expandable fireproof sheet 20, and there is a possibility that flames such as fire, smoke, and the like pass through.

  The object of the present invention is to be able to carry out fire prevention measures even after the outlet box is installed inside the wall, and to check whether the fire prevention measures as designed are being carried out from the outside of the wall, An object of the present invention is to provide a fire prevention structure for an outlet box and its construction method capable of preventing the flame, smoke, etc. from passing through the outlet box when the outlet box is exposed to heat such as a fire. .

  As a result of intensive studies by the present inventors in order to solve the above-mentioned problems, it is a structure of an outlet box installed so as to cover the through hole with respect to a wall having a through hole, and the wall and the outlet box Fire prevention measures for the outlet box, in which a thermally expandable fireproof sheet is inserted on the back plate side inside the outlet box, and a thermally expandable fireproof sheet is installed on the inner periphery of the through hole of the wall The inventors have found that the structure is suitable for the purpose of the present invention, and have completed the present invention.

That is, the present invention
[1] A structure of an outlet box installed so as to cover the through hole with respect to the wall having the through hole,
The outlet box has a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate, and is installed on the wall with the opening side of the outlet box facing the wall,
There is a gap between the wall and the outlet box,
Wire cables are inserted through an insertion hole formed in at least one of the back plate and the side plate of the outlet box,
A first thermally expandable fireproof sheet is inserted on the back plate side inside the outlet box;
The second heat-expandable fireproof sheet is provided on the inner periphery of the through hole of the wall, and provides a fireproof structure for an outlet box.

One of the present invention is
[2] The outlet box is a combination of an outlet box body and a gutter having an opening, which is detachable.
A gutter having the opening is installed on the opening side of the outlet box body,
The support frame is installed outside the through hole of the wall opposite to the side where the outlet box is installed,
A connecting member is inserted through the through-hole of the wall, and the reed plate having the opening and the support frame are removably connected;
The outlet box fire prevention structure according to the above [1], wherein an end portion of the second thermally expandable fireproof sheet reaches the opening of the roof plate.

One of the present invention is
[3] The outlet box fire prevention structure according to [1] or [2], wherein the connecting member supports the second thermally expandable fireproof sheet.

One of the present invention is
[4] The first thermally expandable fireproof sheet is composed of two or more thermally expandable fireproof sheets,
[2] The above [1] to [3], wherein the two or more thermally expandable fireproof sheets are inserted on the back plate side inside the outlet box with the side surfaces of the two or more thermally expandable fireproof sheets facing each other. A fire prevention structure for an outlet box according to any of the above is provided.

One of the present invention is
[5] The first thermally expandable refractory sheet comprises two or more thermally expandable refractory sheets,
The two or more thermally expandable fireproof sheets include a thermally expandable fireproof sheet (A) having a low thermal expansion start temperature and a thermally expandable fireproof sheet (B) having a high thermal expansion start temperature,
The low thermal expansion start temperature thermal expansion fireproof sheet (A) starts expanding at a lower temperature than the high thermal expansion start temperature thermal expansion fireproof sheet (B),
With reference to the direction perpendicular to the back plate of the outlet box, the thermally expandable fireproof sheet (A) having the low thermal expansion start temperature and the thermally expandable fireproof sheet (B) having the high thermal expansion start temperature are (A), (B )
The low thermal expansion start temperature thermal expansion fireproof sheet (A) is disposed on the side opposite to the back plate side inside the outlet box,
The outlet box fire prevention structure according to any one of the above [1] to [4], wherein the thermally expandable fireproof sheet (B) having the high thermal expansion start temperature is disposed on the back plate side inside the outlet box. Is to provide.

One of the present invention is
[6] The first thermally expandable refractory sheet is formed by laminating at least a thermally expandable refractory layer (a) having a low thermal expansion start temperature and a thermal expandable refractory layer (b) having a high thermal expansion start temperature,
The thermally expandable refractory layer (a) having the low thermal expansion start temperature corresponds to the thermal expandable refractory sheet (A) having the low thermal expansion start temperature,
The fireproof structure for an outlet box according to the above [5], wherein the heat-expandable fireproof layer (b) having the high thermal expansion start temperature corresponds to the heat-expandable fireproof sheet (B) having the high thermal expansion start temperature. Is.

One of the present invention is
[7] The wire cables are inserted through the inside of a flexible conduit having a cylindrical fixture at the end,
A cylindrical fixed receiver is installed in the insertion hole of the outlet box,
A cylindrical fixture installed at the end of the flexible conduit is fitted to a cylindrical fixture installed in the insertion hole of the outlet box,
A switchboard is installed on the support frame,
The wire cables inserted through the inside of the flexible conduit are introduced into the outlet box and connected to the switchboard,
The switchboard includes at least one selected from the group consisting of a wired communication outlet, a power outlet, a power switch, a power breaker, a power indicator, and an information display device,
The switchboard and the support frame are covered from the outside of the wall by a decorative plate, and a power outlet, a power switch, and a power breaker of the switchboard can be operated through the opening of the decorative plate, An outlet box fire prevention structure according to any one of the above [1] to [6], in which the indicator lamp and the information display device can be visually recognized.

The present invention also provides
[8] Step (1) of installing an outlet box having a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate, with the opening side of the outlet box facing the wall side When,
A step (2) of inserting an electric cable into an insertion hole formed in at least one of a back plate and a side plate of the outlet box;
Providing a through hole in the wall at a position where a part or all of the through hole of the wall and a part or all of the opening of the outlet box overlap with each other on the basis of the vertical direction of the wall (3) When,
Inserting the first thermally expandable fireproof sheet into the back plate inside the outlet box (4);
Installing a second thermally expandable fireproof sheet on the inner periphery of the through hole in the wall;
A construction method of a fire-protection structure of an outlet box having at least
When carrying out the step (1), a gap is installed between the wall and the outlet box,
After the implementation of the step (1), the step (4) and the step (5) are carried out in any order, and the construction method of the fire prevention structure for the outlet box is provided.

One of the present invention is
[9] A step (6) of installing the support frame outside the through hole of the wall opposite to the side on which the outlet box is installed;
A mortar plate having the opening portion installed in an outlet box, which is a detachable combination of an outlet box body and a mortar plate having an opening portion;
The support frame,
A step (7) of detachably connecting the connecting member inserted through the through-hole of the wall;
Have
When the second thermally expandable refractory sheet in the step (5) is installed on the inner periphery of the through hole of the wall, the end of the second thermally expandable refractory sheet is at the opening of the plate. The construction method of the fireproof structure of the outlet box according to the above [8] is provided.

One of the present invention is
[10] In the step (4), the first thermally expandable fireproof sheet composed of two or more thermally expandable fireproof sheets is inserted into the back plate side inside the outlet box,
The construction method of the fireproof structure for the outlet box according to the above [8] or [9], which is a step of making the side surfaces of the two or more thermally expandable fireproof sheets face each other.

One of the present invention is
[11] In the step (4), the thermally expandable refractory sheet (B) having a high thermal expansion start temperature is inserted on the back plate side inside the outlet box, and then the thermal expandable refractory sheet (A ) Is inserted into the outlet box inside the outlet box, and the thermal expansion refractory sheet having the low thermal expansion start temperature (in the order of (A) and (B) in the order of the vertical direction with respect to the rear panel of the outlet box ( A) is arranged on the side opposite to the back plate side inside the outlet box, and the thermally expandable refractory sheet (B) having the high thermal expansion start temperature is arranged on the back plate side inside the outlet box,
Any of the above [8] to [10], wherein the thermally expandable fireproof sheet (A) having the low thermal expansion start temperature starts expanding at a lower temperature than the thermally expandable fireproof sheet (B) having the high thermal expansion start temperature. The construction method of the fire-protection structure of the outlet box of a crab is provided.

The present invention also provides
[12] A structure of an outlet box installed so as to cover the through hole with respect to the wall having the through hole,
The outlet box has a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate, and is installed on the wall with the opening side of the outlet box facing the wall,
There is a gap between the wall and the outlet box,
For the structure of the outlet box in which the electric cables are inserted through the insertion hole formed in at least one of the back plate and the side plate of the outlet box,
Insert the first thermally expandable fireproof sheet on the back plate side inside the outlet box,
A second heat-expandable fireproof sheet is provided on the inner periphery of the through-hole of the wall, and a fireproof reinforcement method for an outlet box structure is provided.

The fire prevention structure of the outlet box according to the present invention can perform a fire prevention measure on the outlet box even after the outlet box used in the present invention is installed on the wall.
In the conventional fire prevention structure of the outlet box, before installing the outlet box on the wall, fire prevention measures should be taken unless a fire-resistant material such as a heat-expandable fire-resistant sheet or heat-resistant putty is installed at the designated position in the design. Could not do. For this reason, in the conventional fire prevention structure of the outlet box, a wall or the like cannot be installed unless the fire prevention structure of the outlet box is completed, and it takes time to construct the fire prevention structure of the outlet box. There was a problem that the whole construction work was delayed.
On the other hand, the fire prevention structure of the outlet box of the present invention can be easily constructed since it is obtained by using a heat-expandable fireproof sheet after the outlet box is installed on the wall.
If the outlet box can be installed on the wall first, it is not necessary to wait for the completion of the fire prevention structure of the outlet box of the present invention when performing the next construction work, and the building work can be efficiently advanced in a short time. it can.

In the case of the outlet box fire prevention structure of the present invention, the first thermally expandable fireproof sheet and the second thermally expandable fireproof sheet are determined by observing the inside of the outlet box through the through-hole of the wall. It can be easily confirmed whether it is installed at the position of.
The fire prevention structure of the outlet box of the present invention can be easily inspected as to whether it is constructed as designed.

Further, in the case of the outlet box fire prevention structure of the present invention, when the outlet box fire prevention structure is exposed to heat such as a fire, the first thermal expansion as in the conventional outlet box fire prevention structure. There is nothing that prevents the expansion of the refractory fireproof sheet, and the inside of the outlet box is closed by the expansion residue due to the first thermally expandable refractory sheet.
Further, the gap between the outlet box and the wall is also closed by the expansion residue due to the second thermally expandable fireproof sheet.
For this reason, it is possible to prevent the inside of the outlet box from passing flames such as fire, smoke and the like, so that the fire prevention structure of the outlet box of the present invention is excellent in fire resistance.

When the outlet box used in the present invention is directly exposed to a flame such as a fire, there is no particular problem because the first thermally expansive fireproof sheet installed in the outlet box expands quickly.
However, in an actual fire site, the outlet box is not directly exposed to a flame such as a fire, and a flame such as a fire may enter from the through hole side of the wall toward the opening of the outlet box. There is.
When the outlet box is not directly exposed to flames such as fire, before the first thermally expandable fireproof sheet installed in the outlet box expands, flames, smoke, etc. due to fire etc. Concerned about passing through.
For this problem, the fireproof structure of the outlet box of the present invention is used in combination with a thermally expandable fireproof sheet (A) having a low thermal expansion start temperature and a thermally expandable fireproof sheet (B) having a high thermal expansion start temperature. Can be solved.
Even when the outlet box is not sufficiently heated, the thermally expandable refractory sheet (A) having a low thermal expansion start temperature expands to form an expansion residue. The inside of the outlet box is closed by the expansion residue due to the heat-expandable fireproof sheet (A) having a low thermal expansion start temperature from the stage where the liquid does not expand sufficiently.
Thereby, before the first thermally expansible fireproof sheet installed in the outlet box expands, it is possible to solve the problem that flames, smoke and the like due to fire pass through the outlet box.

When installing a conventional fire prevention structure for an outlet box, a sealant such as a heat-resistant putty was used, so the problem was that the area near the construction site of the conventional fireproof structure for an outlet box was soiled by a sealant such as a heat-resistant putty. was there.
On the other hand, when constructing the fire prevention structure of the outlet box of the present invention, it is possible to construct by using the first thermally expandable fireproof sheet and the second thermally expandable fireproof sheet. It is not necessary to use a sealing agent such as putty, and since it can be applied simply by using these thermally expandable fireproof sheets, anyone can easily install it. There is no problem of soiling around the construction site.

FIG. 1 is a schematic perspective view illustrating an outlet box used in the present invention. FIG. 2 is a schematic perspective view illustrating an outlet box used in the present invention. FIG. 3 is a schematic perspective view for explaining the shape of the first thermally expandable fireproof sheet used in the present invention. FIG. 4 is a schematic cross-sectional view of an outlet box used in the present invention. FIG. 5 is a schematic diagram for explaining the shape of a cross section obtained by cutting the internal space surrounded by the side plate of the outlet box by a plane parallel to the wall and the arrangement state of the first thermally expandable fireproof sheet. It is sectional drawing. FIG. 6 is a schematic cross-sectional view of a main part for explaining a construction process of the fire prevention structure 100 for an outlet box according to the first embodiment. FIG. 7 is a schematic cross-sectional view of an essential part for explaining a construction process of the fire prevention structure 100 for an outlet box according to the first embodiment. FIG. 8 is a schematic cross-sectional view of an essential part for explaining a construction process of the fire prevention structure 100 for an outlet box according to the first embodiment. FIG. 9 is a schematic cross-sectional view of an essential part for explaining a construction process of the fire prevention structure 100 for an outlet box according to the first embodiment. FIG. 10 is a schematic diagram for explaining a state in which the inside of the outlet box is observed. FIG. 11 is a schematic cross-sectional view of the fire prevention structure 100 for an outlet box according to the first embodiment. FIG. 12 is a schematic diagram for explaining the fire prevention structure 110 for an outlet box according to the second embodiment. FIG. 13 is a schematic diagram for explaining the fire prevention structure 120 of the outlet box according to the third embodiment. FIG. 14 is a schematic cross-sectional view for explaining an outlet box fire prevention structure 130 according to the fourth embodiment. FIG. 15 is a schematic cross-sectional view for explaining an outlet box fire prevention structure 140 according to the fifth embodiment. FIG. 16 is a schematic cross-sectional view for explaining an outlet box fire prevention structure 150 according to the sixth embodiment. FIG. 17 is a schematic cross-sectional view for explaining a fire prevention structure of a first conventional outlet box. FIG. 18 is a schematic cross-sectional view for explaining a fire prevention structure of a second conventional outlet box.

First, the outlet box used in the present invention will be described.
1 and 2 are schematic perspective views illustrating an outlet box used in the present invention.
An outlet box main body 1a is formed by joining the upper side plate 2, the lateral side plate 3 and the lower side plate 4 to the outer periphery of the back plate 5 without gaps. A rectangular parallelepiped space surrounded by the back plate 5, the upper side plate 2, the lateral side plate 3 and the lower side plate 4 is formed inside the outlet box body 1a, and electric cables are introduced into this space from the outside. Can do.
The side plate composed of the upper side plate 2, the lateral side plate 3 and the lower side plate 4 and the back plate 5 may be joined at a right angle or may be joined so as to include a curved surface.

Further, a flange plate 6 is detachably combined with a screw 7 on each end surface 11 side of the upper side plate 2, the lateral side plate 3 and the lower side plate 4, that is, on the opening 10 side.
The outlet box 1 used in the present invention can be obtained, for example, by detachably combining the outlet box body 1a and the saddle plate 6.

  The said board 6 is provided with respect to the said outlet box main body 1a so that a switchboard etc. (not shown) can be installed easily, The inside of the said board 6 is illustrated in FIG. Thus, a substantially rectangular opening 14 is provided.

The said board 6 has a magnitude | size which can cover the through-hole normally provided in the wall.
Thereby, the outlet side is covered so that the end surface side of the side plate composed of the upper side plate 2, the lateral side plate 3 and the lower side plate 4, that is, the opening 10 side of the outlet box body 1a faces the wall side. A box can be installed.

  As shown in FIG. 2, after the cover plate 6 is detachably combined with the outlet box main body 1a, the opening 10 of the outlet box main body 1a shown in FIG. The part 14 is the same. Thus, the opening of the outlet box 1 is shown in FIG.

  Further, an insertion hole 8 is formed in the upper side plate 2. The unused insertion hole is closed and sealed with a non-combustible material 9. In FIG. 1, a non-combustible material 9 is disposed inside the upper side plate 2 and the through hole is closed and sealed. The same material as the outlet box 1 can be used as the material of the non-combustible material 9.

As shown in FIG. 2, the side plate is screwed into the screw hole 12 including the notch provided in the flange plate 6 and the screw hole 13 provided in the end surface 11 of the side plate. The end plate 6 can be installed on the end surface 11 of the plate. As a result, the outlet box 1 used in the present invention shown in FIG. 1 is obtained.
In addition, a screw hole for fixing a switchboard or the like can be provided in the cover plate 6 as appropriate.

The material of the outlet box 1 used in the present invention is not particularly limited as long as it has fireproof properties. For example, inorganic materials, metals, and the like are used.
As an inorganic thing, things made from ceramics, ceramics, etc. are mentioned, for example.
Moreover, as a metal thing, the thing of 1 type or 2 types or more of things, such as aluminum, copper, steel, stainless steel, tin, lead, etc. are mentioned, for example.
If the outlet box 1 used for this invention will give an example, the metal box for metal conduits and a box cover etc. which are prescribed | regulated to IJSC C8340 will be mentioned, for example. Specifically, those made of soft steel are preferable, and those made of hot-rolled soft iron steel plates are more preferable. More preferably, the hot-rolled mild steel sheet is one specified in JIS G3131.

Next, the first thermally expandable fireproof sheet used in the present invention will be described.
FIG. 3 is a schematic perspective view for explaining the shape of the first thermally expandable fireproof sheet 20 used in the present invention.
The first heat-expandable fireproof sheet 20 used in the present invention may be composed of, for example, two or more strip-shaped heat-expandable fireproof sheets 20a as illustrated in FIG. , as illustrated in FIG. 3 (b), in the thickness direction of the thermally expandable fireproof sheets, it may be made of a combination of two or more of the heat-expandable fire-sheet 20b _1, 20b ₂ and the like, FIG. As illustrated in 3 (c), thermal expansion fireproof layers 20c ₁ and 20c ₂ having different components of the resin composition may be laminated in the thickness direction of the thermally expandable fireproof sheet 20. Good.

The first thermally expandable refractory sheet 20 used in the present invention can be used in combination of a plurality of different thermal expansion start temperatures.
The thermal expansion start temperature in the present invention is a value when the volume increase of the first thermally expandable refractory sheet 20 is started when measurement is performed at a temperature rising rate of 10 ° C./min using a thermomechanical analyzer. Refers to temperature.
In order to change the thermal expansion start temperature of the first thermally expandable fireproof sheet 20, the thermal expansion components contained in the first thermally expandable fireproof sheet 20 are appropriately selected to have different thermal expansion start temperatures. do it. The detailed composition of the first thermally expandable fireproof sheet 20 will be described later.

  There is no limitation in the shape of said 1st thermally expansible fireproof sheet 20, and it can select suitably according to the shape of the backplate 5 of the outlet box used for this invention.

  The first thermally expandable fireproof sheet 20 used in the present invention is preferably flexible. The flexible, heat-expandable fireproof sheet can be easily applied because it can be appropriately deformed when passing through the through-holes in the wall.

When the first thermally expandable fireproof sheet 20 used in the present invention is installed in the outlet box 1, for example, the thermally expandable fireproof sheet 20 a illustrated in FIG. 3 is attached to the back plate 5 inside the outlet box 1. It is preferable to arrange in contact with each other, and it is more preferable to fix the thermally expandable fireproof sheet 20a and the like to the back plate 5 inside the outlet box 1.
As a method of fixing the thermally expandable fireproof sheet 20a or the like to the inner wall of the outlet box, for example, the thermally expandable fireproof sheet 20a or the like is used inside the outlet box by using an adhesive tape having an adhesive layer on one or both sides. A method of fixing the thermally expandable refractory sheet 20a and the like to the back plate 5 inside the outlet box 1 using an adhesive, and a sticky thermally expandable refractory sheet 20a and the like. A method for fixing the thermally expandable fireproof sheet 20a and the like to the back plate 5 inside the outlet box 1 by using a screw, and the like. And the like.
The thermally expandable fireproof sheet having adhesiveness will be described later. For example, a method of adding an adhesive component to the resin component constituting the thermally expandable fireproof sheet, a method of adding an adhesive layer to the thermally expandable fireproof sheet and laminating Etc.

FIG. 4 is a schematic cross-sectional view of an outlet box used in the present invention.
The outlet box 1 used for this invention is installed in a wall with the end surface 11 (refer FIG. 2) of the said side plate facing the wall side. A dashed line aa in FIG. 4 illustrates a cut surface that cuts an internal space surrounded by the side plate of the outlet box by a plane parallel to the wall.

  FIG. 5 is a cross-sectional view obtained by cutting the internal space surrounded by the side plate of the outlet box by a plane parallel to the wall, and the arrangement state of the first thermally expandable fireproof sheet. It is a schematic cross section.

  In FIG. 5, the shape of a cross section obtained by cutting the internal space surrounded by the side plate of the outlet box by a plane parallel to the wall (a dashed line aa in FIG. 4) is represented by reference numeral 15. The shape of the first heat-expandable fireproof sheet 20 is represented by reference numeral 20a.

Of the vertical, horizontal, and thickness of the respective thermally expandable fireproof sheet 20a used for the first thermally expandable fireproof sheet 20, the vertical and horizontal portions are shown as the thermally expandable fireproof sheet 20a in FIG. Yes.
The area of the first heat-expandable fireproof sheet 20 used in the present invention, that is, the area represented by the length and width of each of the heat-expandable fireproof sheets 20a is the side plates 2 and 3 of the outlet box 1. , 4 is preferably in the range of 55 to 100% with respect to the maximum value of the cross-sectional area of the cross-section 15 obtained by cutting the internal space surrounded by a plane parallel to the wall.
When the area of the thermally expandable fireproof sheet 20 is 55% or more with respect to the maximum value of the cross-sectional area of the cross section 15, even when the fire prevention structure of the outlet box of the present invention is exposed to heat such as fire. , Flames and the like can be prevented from passing through the outlet box.
This range is preferably in the range of 65 to 100%, more preferably in the range of 71% to 100%.

The thickness of the first thermally expandable fireproof sheet 20 before heating is t ₀ , and the thickness after heating the heat expandable fireproof sheet before heating under the heating condition of 50 kw / m ² for 30 minutes is defined as t ₁ . In this case, the coefficient of thermal expansion of the first thermally expansible fireproof sheet 20 is defined by t ₁ / t ₀ .
The first thermal expansion fireproof sheet 20 used in the present invention preferably has a thermal expansion ratio in a range of 3 to 100 times.
When the thermal expansion ratio is 3 times or more, the expansion residue of the first heat-expandable fireproof sheet 20 sufficiently closes the inside of the outlet box 1. Further, when the thermal expansion ratio is 100 times or less, the density of the expansion residue of the thermally expandable fireproof sheet can be prevented from being reduced, so that the strength of the expansion residue can be maintained, hot air generated by a fire, etc. This can prevent the expansion residue from collapsing.

Among the first thermally expandable fireproof sheets used in the present invention, the thermal expansion ratio of the first thermally expandable fireproof sheet 20 inserted into the outlet box is in the range of 20 to 100 times. Is preferred. If it is this range, since it will be excellent in shape retainability, it will become easy to insert said 1st thermally expansible fireproof sheet 20 in the outlet box 1 inside.
The thermal expansion ratio of the first thermally expandable fireproof sheet 20 is more preferably in the range of 20 to 60, and even more preferably in the range of 20 to 50.

In the present invention, in addition to the first thermally expandable refractory sheet, a second thermally expandable refractory sheet to be installed inside the through hole of the wall is also used.
The second thermally expandable fireproof sheet is the same as that of the first thermally expandable fireproof sheet described above. When exposed to heat such as a fire, the inside of the through hole of the wall is sufficiently What has the expansion ratio which can be obstruct | occluded is used.

Next, the thickness of the first thermally expandable fireproof sheet 20 used in the present invention will be described.
The distance from the inner surface of the back plate 5 of the outlet box 1 in FIG. 4 described above to the outermost surface of the cover plate 6 of the outlet box 1 is the length L of the depth inside the outlet box 1.
When the length L of the depth varies depending on the location, such as when the back plate 5 of the outlet box 1 includes a curved surface, the value of L is determined from the inner surface of the back plate 5 of the outlet box 1. It is assumed that the maximum distance to the outermost surface of the plate 6 is adopted.

A total thickness t of the thermally expandable refractory sheet, a depth length L (see FIG. 4) inside the outlet box, and a thermal expansion ratio of the thermally expandable refractory sheet represented by t ₁ / t ₀ Is preferably in the range of 1.5 to 8 on the basis of t × (t ₁ / t ₀ ) / L.
When the value of t × (t ₁ / t ₀ ) / L is 1.5 or more, the expansion residue of the thermally expandable refractory sheet 20 can sufficiently block the inside of the outlet box 1. Moreover, when the value of t × (t ₁ / t ₀ ) / L is 8 or less, the expansion residue of the thermally expandable refractory sheet 20 can be maintained densely.
The value of t × (t ₁ / t ₀ ) / L is preferably in the range of 1.5 to 5, and more preferably in the range of 2 to 4.

Next, the material of the first thermally expandable fireproof sheet 20 used in the present invention will be described.
Examples of the material of the heat-expandable fireproof sheet 20 include a material obtained by molding a heat-expandable resin composition into a sheet shape, and a material obtained by laminating a heat-expandable resin composition and a base material into a sheet shape. Etc.
Examples of the substrate include metal plates, metal foils, metal fiber sheets, metal nets, inorganic plates, inorganic fiber sheets, inorganic fiber nets, organic resin plates, organic resin films, organic fiber sheets, and organic fiber nets. It is done.

  Examples of the metal used for the metal plate, metal foil, metal fiber sheet, metal net, and the like include one or more alloys such as aluminum, copper, steel, stainless steel, tin, and lead.

Regarding the relationship between the metal plate and the metal foil, a thickness that can hold a certain shape when one end is fixed and held horizontally with reference to a planar shape that can be inserted into the outlet box 1. In the following description, a metal plate is used as the metal plate, and a metal foil is used that is bent when one end is fixed and held horizontally.
The relationship between the organic resin plate and the organic resin film described later is the same as the relationship between the metal plate and the metal foil.

Examples of the metal fiber sheet include a sheet formed by knitting metal fibers and a sheet formed using a resin or the like without knitting metal fibers.
Examples of the metal net include those formed by combining metal wires into a net shape, and those in which a large number of holes are formed by punching the metal plate or metal fiber sheet using a mold or the like.

Examples of the inorganic plate include a ceramic plate, a calcium silicate plate, a gypsum plate, and a pearlite plate.
Examples of the inorganic fiber used in the inorganic fiber sheet and the inorganic fiber network include rock wool, ceramic wool, glass fiber, silica alumina fiber, alumina fiber, silica fiber, zirconia fiber, and ceramic blanket.
Examples of the inorganic fiber sheet include a sheet formed by knitting inorganic fibers and a sheet formed using a resin or the like without knitting the inorganic fibers.
Examples of the inorganic fiber net include those formed by combining inorganic fibers into a net shape, and those obtained by punching the inorganic plate or inorganic fiber sheet using a mold or the like to form a large number of holes.

Examples of the organic resin plate include a thermoplastic resin plate and a thermosetting resin plate.
Examples of the organic resin film include a thermoplastic resin film and a thermosetting resin film.
Examples of the organic fiber sheet include a thermoplastic resin fiber sheet and a thermosetting resin fiber sheet.
Examples of the organic fiber network include a thermoplastic resin fiber network and a thermosetting resin fiber network.

  There is no particular limitation on the thermoplastic resin and thermosetting resin used for the organic resin plate, the organic resin film, the organic fiber sheet, and the organic fiber network. It is the same as that of the resin component used for a thing.

  Specifically, a thermoplastic resin is preferably used for the organic resin plate and the organic resin film, a polyolefin resin such as a polyethylene resin, a polypropylene resin and a polypentene resin, a polyester resin such as a polyethylene terephthalate resin and a polybutylene terephthalate resin. Etc.

  Examples of organic fibers used in the organic fiber sheet and the organic fiber network include polyolefin resins such as polyethylene resin, polypropylene resin, and polypentene resin, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polyurethane resins, and polyamides. Resin, aramid resin, cotton, cellulose, etc. are mentioned.

Examples of the organic fiber sheet include a woven fabric formed into a sheet shape by knitting organic fibers, and a non-woven fabric formed into a sheet shape using a resin or the like without knitting organic fibers.
Examples of the organic fiber net include those formed by combining organic fibers into a net shape, the organic resin plate, and the organic fiber sheet formed by punching the organic fiber sheet using a mold or the like. .

  There is no limitation in particular in the base material used for this invention, 1 type, or 2 or more types can be selected suitably and can be used.

  If an example of embodiment of the base material used for this invention is given, the aluminum foil laminated glass cloth etc. which are obtained by laminating | stacking aluminum foil and a glass fiber sheet etc. will be mentioned, for example.

Examples of the method of forming the thermally expandable resin composition into a sheet shape include a method of forming the thermally expandable resin composition into a sheet shape by melt extrusion, hot press molding, or the like.
Examples of the method of laminating the thermally expandable resin composition and the base material to form a sheet shape include, for example, a method of melt extruding and laminating the thermally expandable resin composition to the base material, and the base material. And a method of laminating the thermally expandable resin composition by hot press molding or the like, a method of spraying or applying a paint in which the thermally expandable resin composition is dissolved or suspended in a solvent, etc. It is done.

Next, the thermally expandable resin composition will be described.
Examples of the thermally expandable resin composition include those containing a resin component, a thermally expandable component, an inorganic filler, and the like.
Although there is no limitation in the said resin component, if an example is given, a thermoplastic resin, a thermosetting resin, etc. will be mentioned, for example.

Specific examples of the thermoplastic resin include polyolefin resins such as polyethylene resin, polypropylene resin, and polypentene resin, silicone resin, polysulfide resin, polystyrene resin, ABS resin, polycarbonate resin, polyphenylene ether resin, acrylic resin, and polyamide. Resin, polyvinyl chloride resin, polyalkylene ether resin, polyethylene terephthalate resin, polybutylene terephthalate resin,
Natural rubber, butyl rubber, silicone rubber, polychloroprene rubber, polybutadiene rubber, polyisoprene rubber, polyisobutylene rubber, styrene / butadiene rubber, butadiene / acrylonitrile rubber, nitrile rubber, ethylene / α-propylene / diene copolymer, etc. Examples thereof include rubber resins such as olefin copolymer rubber.

Moreover, as said thermosetting resin, an epoxy resin, a polyurethane resin, a polyphenol resin etc. are mentioned, for example.
When using the said resin component, the prepolymer which made the monomer used as the raw material of a resin component react preliminarily can be used.
The said resin component can use 1 type, or 2 or more types.

  Among the resin components used in the present invention, polyolefin resin, rubber resin, urethane resin, and epoxy resin are preferable, and urethane resin and epoxy resin are more preferable. When an epoxy resin is used, it is more preferable to use an epoxy resin because the outlet box forms a dense and firm expansion residue when exposed to heat such as a fire.

As said urethane resin, what is obtained by making isocyanate and polyhydric alcohol react is mentioned, for example.
Examples of the isocyanates include phenylene diisocyanate, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate, dimethyldiphenylmethane diisocyanate, and the like.
Examples of the polyhydric alcohol include polyoxyalkylene polyol, polyester polyol, polyolefin polyol, and acrylic polyol.

  Examples of the epoxy resin include resins obtained by reacting a monomer having an epoxy group with a curing agent.

  Examples of the monomer having an epoxy group include, as a bifunctional glycidyl ether type, a polyethylene glycol type, a polypropylene glycol type, a neopentyl glycol type, a 1,6-hexanediol type, a trimethylolpropane type, and a propylene oxide-bisphenol A. And monomers such as hydrogenated bisphenol A type, bisphenol A type, and bisphenol F type.

  Examples of the glycidyl ester type include monomers such as hexahydrophthalic anhydride type, tetrahydrophthalic anhydride type, dimer acid type, and p-oxybenzoic acid type.

  Further, examples of the polyfunctional glycidyl ether type include monomers such as phenol novolac type, orthocresol type, DPP novolac type, dicyclopentadiene, and phenol type.

  These can use 1 type, or 2 or more types.

Examples of the curing agent include a polyaddition type curing agent and a catalyst type curing agent.
Examples of the polyaddition type curing agent include polyamines, acid anhydrides, polyphenols, polymercaptans, and the like.

  Examples of the catalyst-type curing agent include tertiary amines, imidazoles, and Lewis acid complexes. The method for curing these epoxy resins is not particularly limited, and can be performed by a known method.

  In addition, what adjusted the melt viscosity of the said resin component, a softness | flexibility, adhesiveness, etc. can use what mixed 2 or more types of resin components.

Moreover, a phosphorus compound can be added to the heat-expandable resin composition used in the present invention.
The phosphorus compound is not particularly limited, and examples thereof include red phosphorus,
Various phosphate esters such as triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate,
Metal phosphates such as sodium phosphate, potassium phosphate, magnesium phosphate,
Ammonium polyphosphates,
The compound etc. which are represented by Chemical formula 1 are mentioned.

  These phosphorus compounds can be used alone or in combination of two or more.

  Among these, from the viewpoint of fire resistance, red phosphorus, a compound represented by the following chemical formula, and ammonium polyphosphates are preferable, and ammonium polyphosphates are more preferable in terms of performance, safety, cost, and the like.

In the above chemical formula, R ¹ and R ³ represent hydrogen, a linear or branched alkyl group having 1 to 16 carbon atoms, or an aryl group having 6 to 16 carbon atoms.

R ² is a hydroxyl group, a linear or branched alkyl group having 1 to 16 carbon atoms, a linear or branched alkoxyl group having 1 to 16 carbon atoms, an aryl group having 6 to 16 carbon atoms, or carbon. The aryloxy group of Formula 6-16 is represented.

  Examples of the compound represented by the chemical formula include methylphosphonic acid, dimethyl methylphosphonate, diethyl methylphosphonate, ethylphosphonic acid, propylphosphonic acid, butylphosphonic acid, 2-methylpropylphosphonic acid, t-butylphosphonic acid, 2, 3-dimethyl-butylphosphonic acid, octylphosphonic acid, phenylphosphonic acid, dioctylphenylphosphonate, dimethylphosphinic acid, methylethylphosphinic acid, methylpropylphosphinic acid, diethylphosphinic acid, dioctylphosphinic acid, phenylphosphinic acid, diethylphenylphosphinic acid , Diphenylphosphinic acid, bis (4-methoxyphenyl) phosphinic acid and the like.

  Among them, t-butylphosphonic acid is preferable in terms of high flame retardancy although it is expensive.

  The ammonium polyphosphates are not particularly limited, and examples thereof include ammonium polyphosphate and melamine-modified ammonium polyphosphate. Ammonium polyphosphate is preferable from the viewpoint of flame retardancy, safety, cost, and handleability.

  Examples of commercially available products include “trade name: EXOLIT AP422” and “trade name: EXOLIT AP462” manufactured by Clariant.

  It is considered that the phosphorus compound reacts with metal carbonates such as calcium carbonate and zinc carbonate to promote the expansion of the metal carbonate. In particular, when ammonium polyphosphate is used as the phosphorus compound, a high expansion effect is obtained. can get. It also acts as an effective aggregate and forms a highly shape-retaining residue after combustion.

Next, the thermal expansion component among the components of the thermal expansion resin composition will be described. The thermal expansion component expands upon heating, but the thermal expansion component is not particularly limited, and examples thereof include thermal expansion layered inorganic materials such as vermiculite, kaolin, mica, and thermal expansion graphite.
The said thermal expansion component can obtain as a commercial item what the thermal expansion start temperature changes with structural components. In the present invention, the thermal expansion start temperature of the first thermally expandable refractory sheet 20 can be changed by selecting the thermal expansion components having different thermal expansion start temperatures.

  The thermally expandable graphite is a conventionally known substance, and powders such as natural scaly graphite, pyrolytic graphite, quiche graphite, etc., inorganic acid such as concentrated sulfuric acid, nitric acid, selenic acid, concentrated nitric acid, perchloric acid, Crystalline compound that maintains a carbon layered structure by generating a graphite intercalation compound by treatment with a strong oxidant such as perchlorate, permanganate, dichromate, or hydrogen peroxide. It is a kind of.

  The heat-expandable graphite obtained by acid treatment as described above is preferably further neutralized with ammonia, an aliphatic lower amine, an alkali metal compound, an alkaline earth metal compound, or the like.

  Examples of the aliphatic lower amine include monomethylamine, dimethylamine, trimethylamine, ethylamine, propylamine, and butylamine.

  Examples of the alkali metal compound and the alkaline earth metal compound include hydroxides such as potassium, sodium, calcium, barium, and magnesium, oxides, carbonates, sulfates, and organic acid salts.

  The thermal expandable graphite preferably has a particle size in the range of 20 to 200 mesh.

  When the particle size is smaller than 20 mesh, the degree of expansion of graphite is small, and it is difficult to obtain a sufficient expansion residue. When the particle size is larger than 200 mesh, there is an advantage that the degree of expansion of graphite is large. Or when knead | mixing with an epoxy resin, a dispersibility worsens and a physical property falls easily.

Examples of commercially available neutralized thermally expandable graphite include “GRAFGUARD # 160”, “GRAFGUARD # 220” manufactured by UCAR CARBON, and “GREP-EG” manufactured by Tosoh Corporation.

Next, among the components of the above-mentioned thermally expandable resin composition, the inorganic filler will be described.
The inorganic filler is not particularly limited. For example, silica, diatomaceous earth, alumina, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, calcium hydroxide, hydroxide Magnesium, aluminum hydroxide, basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dosonite, hydrotalcite, calcium sulfate, barium sulfate, gypsum fiber, potassium silicate and other potassium salts, talc, clay, Mica, montmorillonite, bentonite, activated clay, ceviolite, imogolite, sericite, glass fiber, glass beads, silica-based balun, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon bal , Charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum borate, molybdenum sulfide, silicon carbide, stainless steel fiber, zinc borate, various magnetic powders, slag fiber, fly ash, inorganic phosphorus Compound, silica alumina fiber, alumina fiber, silica fiber, zirconia fiber and the like can be mentioned.

  These can use 1 type, or 2 or more types.

  The inorganic filler plays an aggregate role and contributes to an improvement in the strength of expansion residue generated after heating and an increase in heat capacity.

  For this reason, a calcium carbonate, a metal carbonate represented by zinc carbonate, an aluminum hydroxide that gives an endothermic effect during heating in addition to an aggregate role, and a water-containing inorganic material represented by magnesium hydroxide are preferred. An earth metal and a metal carbonate of the periodic table IIb or a mixture of these with the water-containing inorganic substance are preferable.

  When the inorganic filler used in the present invention is granular, the particle size is preferably in the range of 0.5 to 200 μm, more preferably in the range of 1 to 50 μm.

  When the amount of the inorganic filler added is small, the dispersibility largely affects the performance, so that a small particle size is preferable. However, when the particle size is 0.5 μm or more, secondary aggregation can be prevented, and the dispersibility is good. It can prevent getting worse.

  In addition, when the amount of inorganic filler added is large, the viscosity of the resin composition increases and moldability decreases as high filling proceeds, but the viscosity of the resin composition is decreased by increasing the particle size. From the point of being able to do, the thing with a large particle size is preferable among the said range.

  In addition, if a particle size is 200 micrometers or less, it can prevent that the surface property of a molded object and the mechanical physical property of a resin composition fall.

Among the inorganic fillers, calcium carbonate, zinc carbonate and other metal carbonates that play an aggregate role in particular,
Aluminum hydroxide that gives an endothermic effect during heating in addition to the aggregate role,
A hydrous inorganic material such as magnesium hydroxide is preferred.

  It is considered that the combined use of the hydrated inorganic substance and the metal carbonate greatly contributes to improving the strength of the combustion residue and increasing the heat capacity.

  Among the inorganic fillers, in particular, water-containing inorganic substances such as aluminum hydroxide and magnesium hydroxide are endothermic due to the water generated by the dehydration reaction during heating, and the temperature rise is reduced and high heat resistance is obtained. This is preferable in that the oxide remains as a combustion residue and this acts as an aggregate to improve the strength of the combustion residue.

  Magnesium hydroxide and aluminum hydroxide have different temperature ranges that exhibit dehydration effects, so when used together, the temperature range that exhibits dehydration effects becomes wider, and more effective temperature rise suppression effects can be obtained. It is preferable to do.

  When the particle size of the water-containing inorganic substance is small, the bulk increases and it becomes difficult to achieve high filling. Therefore, in order to increase the dehydration effect, a large particle size is preferable. Specifically, it is known that when the particle size is 18 μm, the filling limit amount is improved by about 1.5 times compared to the particle size of 1.5 μm. Further, by combining a large particle size and a small particle size, higher packing can be achieved.

  As a commercial item of the said water-containing inorganic substance, for example, as aluminum hydroxide, “trade name: Hygielite H-42M” (manufactured by Showa Denko) with a particle diameter of 1 μm, “trade name: Hygilite H-31 with a particle diameter of 18 μm”. (Made by Showa Denko KK) and the like.

  Examples of commercially available calcium carbonate include “trade name: Whiten SB red” (manufactured by Shiraishi Calcium Co., Ltd.) having a particle size of 1.8 μm, and “trade name: BF300” (manufactured by Bihoku Flour & Chemical Co., Ltd.) having a particle size of 8 μm. Etc.

  As explained at the beginning, examples of the thermally expandable resin composition used in the present invention include those composed of the resin composition described above, the thermally expanded component, the resin composition containing the inorganic filler, and the like. Although possible, the following describes these formulations.

  The resin composition preferably contains 20 to 350 parts by weight of the thermal expansion component and 50 to 400 parts by weight of the inorganic filler with respect to 100 parts by weight of the resin component. The total of the thermal expansion component and the inorganic filler is preferably in the range of 200 to 600 parts by weight.

  Such a resin composition expands by heating to form an expansion residue. According to this composition, the thermally expandable resin composition expands by heating such as a fire, and can obtain a necessary volume expansion coefficient. After expansion, a residue having a predetermined heat insulation performance and a predetermined strength is obtained. It can be formed, and stable fireproof performance can be achieved.

When the amount of the thermal expansion component is 20 parts by weight or more, the expansion ratio is improved, and sufficient fire resistance and fire prevention performance can be obtained.
On the other hand, when the amount of the thermal expansion component is 350 parts by weight or less, the pseudo-collecting force is improved, and the strength of the molded product is increased.
Moreover, since the remaining volume after combustion can be ensured as the amount of the inorganic filler is 50 parts by weight or more, a sufficient expansion residue can be obtained. Furthermore, since the ratio of combustibles decreases, flame retardance improves.

  On the other hand, when the amount of the inorganic filler is 400 parts by weight or less, the blending ratio of the resin component increases, and sufficient cohesive force can be obtained, so that strength as a molded product can be ensured.

  When the total amount of the thermal expansion component and the inorganic filler in the resin composition is 200 parts by weight or more, the amount of residue after combustion can be ensured, and sufficient fireproof performance can be obtained. It can prevent deterioration of physical properties and can withstand long-term use.

  Further, the thermally expandable resin composition used in the present invention is a range that does not impair the object of the present invention, and, if necessary, in addition to antioxidants such as phenol-based, amine-based, sulfur-based, etc. Additives such as additives, antistatic agents, stabilizers, crosslinking agents, lubricants, softeners, pigments, and tackifiers such as polybutenes and petroleum resins.

Next, the manufacturing method of the said thermally expansible resin composition is demonstrated.
The method for producing the thermally expandable resin composition is not particularly limited, for example, a method in which the thermally expandable resin composition is suspended in an organic solvent, heated and melted to form a paint, The thermally expandable resin composition can be obtained by a method of dispersing in a solvent to prepare a slurry, or a method of melting the thermally expandable resin composition under heating.

  The thermally expandable resin composition is obtained by kneading the above components using a known apparatus such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneader mixer, a kneading roll, a lycra machine, and a planetary stirrer. Can be obtained.

  In addition, when using a thermosetting resin as a resin component of the thermally expandable resin composition, a filler is kneaded separately into a thermoplastic resin monomer and a curing agent, and a static mixer immediately before molding, It can also be obtained by kneading with a dynamic mixer or the like.

  By the method described above, the thermally expandable resin composition used in the present invention can be obtained. The first thermally expandable refractory sheet 20 can be obtained by a method such as melt extrusion or hot press molding of the thermally expandable resin composition. The same applies to the second thermally expandable fireproof sheet 30 used in the present invention.

  As described above, the first thermally expandable fireproof sheet 20 and the second thermally expandable fireproof sheet 30 used in the present invention are obtained by molding a thermally expandable resin composition into a sheet shape, The thing etc. which laminated | stacked the functional resin composition and the base material and shape | molded in the shape of the sheet | seat can be used.

  From the viewpoint of handleability, the first heat-expandable fireproof sheet 20 and the second heat-expandable fireproof sheet 30 are made by laminating a metal foil layer, a heat-expandable resin layer, an inorganic fiber layer, and the like. Is preferred. In addition to melt coextrusion, hot pressing, etc., these layers include means for attaching each layer with an adhesive.

  Commercially available products can be appropriately selected and used for the first heat-expandable fireproof sheet 20 and the second heat-expandable fireproof sheet 30 used in the present invention. As such a commercial product, for example, Fibro (manufactured by Sekisui Chemical Co., Ltd. (registered trademark. Sheet material containing a resin composition containing epoxy resin, rubber, and thermally expandable graphite)), manufactured by Sumitomo 3M Co., Ltd. Fire barrier (sheet material composed of a resin composition containing chloroprene rubber and verculite, expansion coefficient: 3 times, thermal conductivity: 0.20 kcal / m · h · ° C.), medhicut (manufactured by Mitsui Kinzoku Paint Chemical Co., Ltd.) Sheet material comprising a resin composition containing a polyurethane resin and thermally expandable graphite, expansion coefficient: 4 times, thermal conductivity: 0.21 kcal / m · h · ° C.) and the like.

Next, the wall used in the present invention will be described.
Examples of the wall used in the present invention include a building wall, a partition wall, a floor, a ceiling, and the like, a steel plate provided in a waterproof compartment of a ship and a cabin.

Examples of the material used for the wall include concrete, incombustible board, steel plate and the like.
Examples of the non-combustible board include inorganic fiber boards formed from inorganic fibers, heat-resistant panels, and the like.

  As the inorganic fiber board, for example, a glass wool, rock wool, ceramic wool, gypsum fiber, carbon fiber, stainless steel fiber, slag fiber, silica alumina fiber, alumina fiber, silica fiber, zirconia fiber and other inorganic fibers as a sintering agent, Examples include boards obtained by molding using thermoplastic resins, adhesives, and the like.

Examples of the heat resistant panel include a cement panel and an inorganic ceramic panel.
Examples of the cement-based panel include hard wood piece cement boards, inorganic fiber-containing slate boards, lightweight cellular concrete boards, mortar boards, and precast concrete boards.
Examples of the inorganic ceramic panel include a gypsum board, a calcium silicate board, a calcium carbonate board, a mineral wool board, and a ceramic board.

  Here, as the gypsum board, specifically, a lightweight material such as saw dust or pearlite is mixed into calcined gypsum, and cardboard is formed on both sides. For example, ordinary gypsum board (JIS A6901 compliant: GB-R) is used. ), Decorative gypsum board (JIS A6911 compliant: GB-D), waterproof gypsum board (JIS A6912 compliant: GB-S), reinforced gypsum board (JIS A6913 compliant: GB-F), sound-absorbing gypsum board (JIS A6301 compliant: GB) -P) and the like.

  The material used for the said wall can use 1 type, or 2 or more types.

Moreover, there is no limitation in the wall used for this invention, What is normally used for a wall can be selected suitably, and can be used. As a specific shape of the wall, for example, a wall having no space inside, a hollow wall having a space inside, or the like can be used.
Examples of the hollow wall include a structure in which the heat-resistant panel or the like is fixed to a frame material such as a metal frame or a steel frame.
When a hollow wall is used as the wall, inorganic fibers or the like can be installed inside the hollow wall.
Examples of the inorganic fiber include glass wool, rock wool, ceramic wool, gypsum fiber, carbon fiber, stainless steel fiber, slag fiber, silica alumina fiber, alumina fiber, silica fiber, and zirconia fiber.

Next, an embodiment of the present invention using the outlet box will be described in more detail with reference to the drawings.
In addition, this invention is not limited at all by these Examples.

FIGS. 6 to 9 are schematic cross-sectional views of main parts for explaining the construction process of the outlet box fire prevention structure 100 according to the first embodiment.
As shown in FIG. 6, the outlet box 1 attached to the stud with a metal fitting or the like is installed inside the wall 40.
The outlet box is made of metal, and the wall 40 is formed by stacking two reinforced gypsum boards 41a having a thickness of 21 mm.
The structure of the outlet box 1 used in Example 1 is the same as that used in FIGS.
The outlet box 1 shown in FIG. 6 can be installed on a wall (not shown) by fixing it to a stud using a metal fitting or the like. Metal fittings, studs, and the like for installing the outlet box 1 on the wall are commercially available, and commercially available metal fittings, studs, and the like can be appropriately selected and used.

When the outlet box 1 is installed on the wall 40 using a stud, it is preferably installed close to the wall 40.
In the case of the outlet box 1 used in the first embodiment shown in FIG. 6, the screw 7 protrudes on the opening 14 side of the outlet box 1. Therefore, when the outlet box 1 is fixed to a wall, a gap 44 is formed between the wall and the outlet box 1.

Next, as shown in FIG. 6, electric cables 50 are inserted into the outlet box 1 from the insertion hole 8 (see FIG. 1) formed in the outlet box 1.
Examples of the electric cables 50 used in the present invention include power line cables, antenna line cables, and optical fiber cables. Electric wires and cables can be single core or two or more cores.

The power line cable, the antenna line cable, and the like are preferably made by coating a metal wiring such as copper with an insulator such as polyethylene resin, vinyl chloride resin, or glass fiber.
As the optical fiber cable, an optical fiber made of synthetic resin, glass, or the like can be used.

In the electric cable 50 used in the first embodiment, the power line cable 51 is inserted through the flexible electric cable 52.
The flexible electric conduit 52 is made of a synthetic resin and can be freely bent, and a commercially available product can be appropriately selected and used. The flexible conduit 52 is preferably one that conforms to JIS C8411.

A cylindrical fixture 60 is fixed to the end of the flexible conduit 52 on the outlet box 1 side. On the other hand, a cylindrical fixed receiver 61 is closely attached to the insertion hole 8 of the outlet box 1 without a gap. By fitting and fixing the cylindrical fixture 60 and the cylindrical fixture 61, the end of the flexible conduit 52 can be installed in close contact with the outlet box 1.
As the tubular fixture 60 and the tubular fixture 61, those commercially available as pipe connectors can be appropriately selected and used.

  Next, as shown in FIG. 7, a through hole 43 is formed in the wall 40. The opening 14 of the outlet box 1 and the through hole 43 of the wall 40 are a part or all of the through hole 43 of the wall 40 and the opening of the outlet box 1 with respect to the vertical direction of the wall 40. 14 is adjusted so that part or all of 14 overlap each other.

In the case of the first embodiment, the outlet box 1 attached to the stud with a metal fitting or the like is installed inside the wall 40. A through hole 43 was made in the wall 40 corresponding to the position of the outlet box 1.
On the other hand, after the through hole 43 is opened in the wall 40, the outlet box 1 attached to the stud with a metal fitting or the like can be installed in the wall 40 so as to cover the through hole 43.

Next, as shown in FIG. 8, the first heat-expandable fireproof sheet 20 is inserted into the back plate 5 inside the outlet box 1.
The shape of the first thermally expandable fireproof sheet 20 is the same as that of the two or more strip-shaped thermally expandable fireproof sheets 20a shown in FIG.

In the case of Example 1, Fiblock (registered trademark, a thermally expandable fireproof sheet containing an epoxy resin) manufactured by Sekisui Chemical Co., Ltd. was used as the thermally expandable fireproof sheet 20a.
The heat-expandable fireproof sheet 20a can be attached to the back plate 5 inside the outlet box 1 because an adhesive component is added.
The thermally expandable fireproof sheets 20a were laid on the back plate 5 inside the outlet box 1 so that the side surfaces of the two or more thermally expandable fireproof sheets 20a face each other.
The first thermally expandable fireproof sheet 20 used in Example 1 has an expansion residue that sufficiently closes the inside of the outlet box 1 when the outlet box 1 is heated by a flame such as a fire. The expansion factor, thickness, etc. can be determined as will occur.

Next, as shown in FIG. 9, the second thermally expandable refractory sheet 30 is installed on the inner periphery 42 of the through hole 43 formed in the wall 40.
When the outlet box 1 is heated by a flame such as a fire, the second thermally expandable fireproof sheet 30 used in the first embodiment includes the inside of the through hole 43 formed in the wall 40 and the wall. The expansion ratio, thickness, and the like can be determined so that an expansion residue that sufficiently closes the gap 44 between the outlet 40 and the outlet box 1 is generated.

The end of the second thermally expandable fireproof sheet 30 reaches the opening 14 of the wall plate 6 of the outlet box 1.
Here, the meaning that the end portion of the second thermally expandable fireproof sheet 30 reaches the opening portion 14 of the plate 6 of the outlet box 1 means that the plate is parallel to the wall 40. 6 refers to the case where the end of the second thermally expandable fireproof sheet 30 is inside the outlet box 1 with reference to the cross section taken along the line 6, and the outermost surface of the opening 14 of the outlet box 1 and the second And the end of the second thermally expandable fireproof sheet 30 may be located inside the outlet box 1 with respect to the outermost surface of the outlet box 1. included.

  In the case of the first embodiment, the first thermally expandable fireproof sheet 20 is installed in the outlet box 1, and then the second perimeter is formed on the inner periphery 42 of the through hole 43 formed in the wall 40. Although the heat-expandable fireproof sheet 30 is installed, the installation order of the first heat-expandable fireproof sheet 20 and the second heat-expandable fireproof sheet 30 may be reversed.

FIG. 10 is a schematic diagram for explaining a state in which the inside of the outlet box 1 is observed from the side of the wall 40 opposite to the side on which the outlet box 1 is installed, with the vertical direction of the wall 40 as a reference. .
For convenience of explanation, FIG. 10 shows only the wall 40, the flange plate 6, the first thermally expandable fireproof sheet 20, and the second thermally expandable fireproof sheet 30.

As shown in FIG. 10, the second heat-expandable fireproof sheet 30 is installed in the through hole 43 of the wall 40 without any gap, and the first heat-expandable sheet is disposed on the back plate 5 side of the outlet box 1. Fireproof sheets 20 are laid down.
In FIG. 10, the portion where the first thermally expandable fireproof sheet 20 is visible is represented by a solid line, and the first thermally expandable fireproof sheet 20 is covered by the second thermally expandable fireproof sheet 30. The parts that cannot be seen are represented by broken lines.
In addition, a cut 31 is provided in the second thermally expandable fireproof sheet 30 so that the connecting member 62 can be installed in the saddle plate 6 from the front side of the wall 40.

  As shown in FIG. 10, the installation state of the first thermally expandable fireproof sheet 20 with respect to the outlet box 1 and the second thermally expandable fireproof sheet 30 with respect to the inner periphery 42 of the through hole 43 of the wall 40. The installation status can be confirmed directly with the naked eye even after the outlet box 1 is installed on the wall 40.

In the case of the conventional fire prevention structure of the outlet box, after installing the outlet box on the wall, it was difficult to confirm from the outside of the wall whether or not the fire prevention measures were implemented for the outlet box as designed. .
On the other hand, in the case of the outlet box fire prevention structure 100 according to the first embodiment, it can be easily confirmed from the outside of the wall 40 whether or not the outlet box 1 is being fired as designed. . This also applies to the following embodiments.

Next, as shown in FIG. 11, the end of the power line cable 51 is connected to the switchboard 70.
The switchboard 70 includes a wired communication outlet for connecting an Internet line, a telephone line, etc., a power outlet for supplying power such as 100 V and 200 V, a power switch for controlling the supply of power, a constant Power breaker for cutting off current when using the above power, Energizing indicator lamp for displaying whether or not power is being supplied, Information display for displaying current time, operating status of control equipment, etc. Equipment etc. can be installed.
After the end of the power line cable 51 is connected to the switchboard 70, the switchboard 70 is installed on the support frame 71.

Next, the support frame 71 was installed outside the through hole 43 of the wall 40 on the side opposite to the side on which the outlet box 1 was installed.
Subsequently, the connecting member 62 was inserted through the through hole 43 of the wall 40, and the flange plate 6 and the support frame 71 of the outlet box 1 were detachably fixed by screws.
The support frame member 71 and the connecting member 62 are made of metal, and as with the outlet box 1, the outlet box fire prevention structure 100 according to the first embodiment has a constant shape even when exposed to heat such as a fire. Can be maintained.

As shown in FIG. 11, the connecting member 62 supports the second thermally expandable fireproof sheet 30 installed on the inner periphery 42 of the through hole 43 formed in the wall 40.
The connecting member 62 supports the second thermally expandable fireproof sheet 30 installed on the inner periphery 42 of the through hole 43 formed in the wall 40, so that the second thermally expandable fireproof sheet 30 is It is possible to prevent the inside of the through-hole 43 formed in the wall 40 from hanging down, and to exhibit the fire resistance performance as designed.

The second thermally expansible fireproof sheet 30 is provided with a cut 31, and the connecting member 62 is inserted through the cut 31.
The shape of the connecting member 62 is not particularly limited as long as it can detachably fix the flange plate 6 and the support frame 71, and a shape that matches the shape of the outlet box 1 or the like is appropriately selected. You can select and use.

Next, the decorative plate 72 is installed so as to cover the switchboard 70 and the support frame 71 from the outside of the wall 40. The decorative plate 72 can be fixed to the support frame 71 by fixing means such as screws.
The decorative plate 72 is provided with an opening, and from the outside of the wall 40, through the opening of the decorative plate 72, a wired communication outlet, a power outlet, a power switch, a power breaker, etc. of the switchboard are provided. It can be operated and the power indicator lamp, the information display device, etc. of the switchboard can be visually recognized.

Through the above steps, the outlet box fire prevention structure 100 according to the first embodiment is obtained.
When the outlet box fire protection structure 100 according to the first embodiment is exposed to heat such as a fire, the expansion residue generated by the first thermally expandable fireproof sheet 20 closes the inside of the outlet box 1. Further, the expansion residue generated by the second thermally expandable fireproof sheet 30 closes the inside of the through hole 43 of the wall 40 and the gap 44 between the wall 40 and the outlet box 1.
In this way, due to the expansion residue generated by each of the first thermally expandable fireproof sheet 20 and the second thermally expandable fireproof sheet 30, the through hole 43 of the wall 40, the interior of the outlet box 1, It is possible to prevent flames such as fire, smoke, and the like from diffusing through the gap 44 between the outlet box 1 and the wall 40.
Further, the fire prevention structure 100 for an outlet box according to the first embodiment does not require the use of a sealant such as a heat-resistant putty and can be easily constructed.

FIG. 12 is a schematic diagram for explaining the fire prevention structure 110 for an outlet box according to the second embodiment.
The outlet box fire prevention structure 110 according to the second embodiment is a modification of the outlet box fire prevention structure 100 according to the first embodiment.
In the case of FIG. 12, for convenience of explanation, only the first thermally expandable refractory sheet 20, the roof plate 6, the wall 40, and the second thermally expandable refractory sheet 30 are described by solid lines, A part of the roof plate 6 covered with the second thermally expandable fireproof sheet 30 and a space 90 on the back side of the wall 40 are indicated by broken lines.

The outlet box fire prevention structure 110 according to the second embodiment has a larger through-hole 43 provided in the wall 40 than the outlet box fire prevention structure 100 according to the first embodiment. Other than that is the same as the case of the fire prevention structure 100 of the outlet box according to the first embodiment.
When the through hole 43 provided in the wall 40 is large, a gap is likely to be generated between the wall plate 6 of the outlet box 1 and the wall 40.
However, in the case of the outlet box fire prevention structure 110 according to the second embodiment, the second thermally expandable fireproof sheet 30 is installed on the inner periphery 42 of the through hole 43 formed in the wall 40. For this reason, when the fire protection structure 110 of the outlet box according to the second embodiment is exposed to heat such as a fire, the expansion residue generated by the second thermally expandable fireproof sheet 30 penetrates the wall 40. The inside of the hole 43 and the gap between the wall 40 and the outlet box 1 are closed. Thereby, the fire-protection structure 110 of the outlet box according to the second embodiment is excellent in fire resistance.
Further, the fire prevention structure 100 for an outlet box according to the second embodiment does not require the use of a sealant such as a heat-resistant putty, and can be easily constructed.

FIG. 13 is a schematic diagram for explaining the fire prevention structure 120 of the outlet box according to the third embodiment.
The outlet box fire prevention structure 120 according to the third embodiment is a modification of the outlet box fire prevention structure 100 according to the first embodiment.
In the case of FIG. 13, for convenience of explanation, only a part of the first thermally expandable fireproof sheet 20, the second thermally expandable fireproof sheet 30, a part of the roof plate 6, and the wall 40 are indicated by solid lines. It describes, and a part of said 1st thermally expansible fireproof sheet 20 and a part of said gutter board 6 are described with the broken line.

  The outlet box fire-protection structure 120 according to the third embodiment is smaller in the through hole 43 provided in the wall 40 than the case of the outlet box fire-protection structure 100 according to the first embodiment. Other than that is the same as the case of the fire prevention structure 100 of the outlet box according to the first embodiment.

When the through hole 43 provided in the wall 40 is small, a gap is likely to be generated between the outlet box 1 and the wall 40.
However, even in the case of the outlet box fire-protection structure 120 according to the third embodiment, the first thermally expandable fireproof sheet 20 is installed inside the outlet box 1. Therefore, by adjusting the expansion ratio and thickness of the first heat-expandable fireproof sheet 20, even when the fire prevention structure 120 of the outlet box according to the third embodiment is exposed to heat such as fire, the first The expansion residue generated by the heat-expandable fireproof sheet 20 closes the gap between the wall 40 and the outlet box 1. Thereby, the fire prevention structure 120 of the outlet box according to the third embodiment is excellent in fire resistance.
Further, the outlet box fire prevention structure 100 according to the third embodiment does not require the use of a sealant such as a heat-resistant putty and can be easily constructed.

FIG. 14 is a schematic cross-sectional view for explaining an outlet box fire prevention structure 130 according to the fourth embodiment.
The outlet box fire-protection structure 130 according to the fourth embodiment is a modification of the outlet box fire-protection structure 100 according to the first embodiment.
The outlet box 1 used in the outlet box fire prevention structure 100 according to the first embodiment is installed inside the wall 40. For this reason, the outlet box 1 may not be directly heated by a flame such as a fire, and a flame such as a fire may enter the opening 14 of the outlet box 1 from the through hole 43 side of the wall 40.

The second heat-expandable fireproof sheet 30 is adhered to the inner surface of the through hole 43 of the wall 40, but the temperature of the wall 40 does not rise easily even when exposed to a flame such as a fire. Therefore, the expansion timing of the second thermally expandable fireproof sheet 30 may be delayed.
When the outlet box 1 is not directly exposed to a flame such as a fire, before the first thermally expansible fireproof sheet 20 installed in the outlet box 1 expands, the flame, smoke, etc. due to the fire etc. Passing through the outlet box 1 can be considered.

The outlet box fire prevention structure 130 according to the fourth embodiment has a structure that can solve this problem. Specifically, as in the case of FIG. 3B, the first thermally expansive fireproof sheet 20 used in the fireproof structure 130 of the outlet box according to the fourth embodiment has two or more thermal expansions. The fireproof sheets 20b ₁ and 20b ₂ are used in combination.

In the case of Example 4, the first thermal expansion fireproof sheet 20 has a thermal expansion start temperature in the range of 80 to 250 ° C., a low thermal expansion start temperature thermal expansion fireproof sheet (A), and a high thermal expansion start temperature. In combination with the thermally expandable fireproof sheet (B).
The thermal expansion start temperature of the low thermal expansion start temperature thermal expansion fireproof sheet (A) is preferably in the range of more than 80 ° C. and 150 ° C. or less, and the high thermal expansion start temperature thermal expansion fireproof sheet (B ) Is preferably in the range of more than 150 ° C. and 250 ° C. or less.

The low thermal thermal expansion fireproof sheet expansion starting temperature (A) corresponds to the thermal expansion fireproof sheet 20b _1, intumescent fireproof sheets of high thermal expansion starting temperature (B) corresponds to the thermal expansion fireproof sheet 20b ₂ .
The heat-expandable fireproof sheet (A) having the low thermal expansion start temperature starts expanding from a temperature lower than that of the heat-expandable fireproof sheet (B) having the high thermal expansion start temperature.
Inside the outlet box 1, the low thermal expansion start temperature thermal expansion fireproof sheet (A) is arranged on the opening 14 side of the outlet box 1 with respect to the vertical direction of the wall 40, and the high thermal expansion start temperature By disposing the thermally expandable fireproof sheet (B) on the back plate 5 side of the outlet box 1, the inside of the outlet box 1 can be closed even at a relatively low temperature in the initial stage of the fire.

  Normally, expansion of a thermally expandable refractory sheet that begins to expand at a relatively low temperature tends to end at a relatively low temperature. On the other hand, the expansion of the thermally expandable refractory sheet that begins to expand at a relatively high temperature tends to end at a relatively high temperature.

  When only the thermal expansion fireproof sheet (A) having the low thermal expansion start temperature is used as the first thermal expansion fireproof sheet 20 used in the present invention, the wire cables inserted through the outlet box 1 are used. In some cases, the expansion of the heat-expandable fireproof sheet (A) having the low thermal expansion start temperature may stop before 50 or the like is sufficiently melted and burnt down by the heat of a fire or the like.

  On the other hand, in the case of the fireproof structure 130 of the outlet box according to Example 4, the thermally expandable fireproof sheet (A) having the low thermal expansion start temperature and the thermally expandable fireproof sheet (B) having the high thermal expansion start temperature are used. Even if the expansion of the thermally expandable refractory sheet (A) having the low thermal expansion start temperature stops, the high thermal expansion is performed when the outlet box 1 is continuously heated by heat such as a fire. The thermal expansion refractory sheet (B) at the start temperature continues to expand. For this reason, the inside of the outlet box 1 can be reliably closed.

Further, the thermal expansion fireproof sheet 20b ₂ having a thickness of the thermal expansion fireproof sheet (A) having the low thermal expansion start temperature smaller than the thickness of the thermal expansion fireproof sheet (B) having the high thermal expansion start temperature is used. Thus, the first thermally expandable fireproof sheet 20 can be more easily inserted into the back plate 5 side of the outlet box 1.

  In the case of Example 4, two types of first thermally expandable fireproof sheets 20 having different thermal expansion start temperatures were used, but three or more types of first thermally expandable fireproof sheets 20 having different thermal expansion start temperatures were used. It can also be used.

FIG. 15 is a schematic cross-sectional view for explaining an outlet box fire prevention structure 140 according to the fifth embodiment.
The outlet box fire prevention structure 140 according to the fifth embodiment is a modification of the outlet box fire prevention structure 130 according to the fourth embodiment.
In the case of Example 4, two or more heat-expandable fireproof sheets 20b1 and 20b2 were used in combination as the first heat-expandable fireproof sheet 20. On the other hand, in the case of Example 4, as illustrated in FIG. 3 (c), the resin composition in the thickness direction of the thermally expandable fireproof sheet 20 c is used as the first thermally expandable fireproof sheet 20. The difference is that the thermally expanded refractory layers 20c ₁ and 20c ₂ having different components are laminated.
The thermal expansion refractory layer 20c ₁ corresponds to the thermal expansion refractory sheet 20b ₁ in Example 4, and the thermal expansion refractory layer 20c ₂ corresponds to the thermal expansion refractory sheet 20b ₂ .
As said 1st thermally expansible fireproof sheet 20 used for this invention, what contains two or more thermal expansion fireproof layers which have different thermal expansion start temperature can also be used.

FIG. 16 is a schematic cross-sectional view for explaining an outlet box fire prevention structure 150 according to the sixth embodiment.
The outlet box fire prevention structure 150 according to the sixth embodiment is a modification of the outlet box fire prevention structure 100 according to the first embodiment.

In the outlet box fire prevention structure 150 according to the sixth embodiment, the clearance 44 between the outlet box 1 and the wall 40 is larger than that in the outlet box fire prevention structure 100 according to the first embodiment. Other than that is the same as the case of the fire prevention structure 100 of the outlet box according to the first embodiment.
The gap 44 between the outlet box 1 and the wall 40 is preferably in the range of 1 to 50 mm, more preferably in the range of 5 to 40 mm, and even more preferably in the range of 10 to 30 mm.
In the case of the outlet box fire prevention structure 150 according to the sixth embodiment, the connecting member 62 supports the second thermally expandable fireproof sheet 30. For this reason, the second thermally expandable fireproof sheet 30 is fixed to the inner periphery of the through hole 43 formed in the wall 40.
When the fire prevention structure 150 of the outlet box according to the sixth embodiment is exposed to heat such as a fire, the second thermally expandable fireproof sheet 30 expands.
As described above, even if the outlet box 1 and the wall 40 are separated from each other, the second thermally expandable fireproof sheet 30 can fill the gap 44.

DESCRIPTION OF SYMBOLS 1 Outlet box 1a Outlet box main body 2 Upper side plate 3 Lateral side plate 4 Lower side plate 5 Back plate 6 Girder plate 7 Screw 8 Insertion hole 9 Nonflammable material 10 Opening part 11 of outlet box main body End face 12, 13 Screw hole 14 Outlet box 1 of the opening 15 outlet box cross section 20 first intumescent fireproof sheets _{20a, 20b 1, 20b 2,} 81 thermally expandable fireproof sheet _20c 1, 20c ₂ intumescent fireproof layer 21 spread preventing portion 30 second Thermally expandable fireproof sheet 31 Cuts 40, 41 Wall 41a Reinforced gypsum board 42 Inner circumference 43 of through-holes Through-hole 44 Clearance 50 Electric cable 51 Power cable 52 Flexible electric wire tube 60 Cylindrical fixture 61 Cylindrical fixed fixture 62 connecting member 70 switchboard 71 support frame 72 decorative plate 73 holding frame 74 wiring terminal 80 heat resistant putty 9 Cutting surface length of L outlet box Depth of the wall inside the space 100,110,120,130,140,150 outlet box fire measures structure dashed line a-a outlet box

Claims (12)

For a wall having a through hole, the outlet box is installed so as to cover the through hole,
The outlet box has a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate, and is installed on the wall with the opening side of the outlet box facing the wall,
There is a gap between the wall and the outlet box,
Wire cables are inserted through an insertion hole formed in at least one of the back plate and the side plate of the outlet box,
A first thermally expandable fireproof sheet is inserted on the back plate side inside the outlet box;
A fireproof structure for an outlet box, wherein the second thermally expandable fireproof sheet is installed on the inner periphery of the through hole of the wall. The outlet box is a detachable combination of an outlet box main body and a plate having an opening,
A gutter having the opening is installed on the opening side of the outlet box body,
The support frame is installed outside the through hole of the wall opposite to the side where the outlet box is installed,
A connecting member is inserted through the through-hole of the wall, and the reed plate having the opening and the support frame are removably connected;
The fireproof structure for an outlet box according to claim 1, wherein an end of the second thermally expandable fireproof sheet reaches an opening of the roof plate.   The fireproof structure for an outlet box according to claim 1 or 2, wherein the connecting member supports the second thermally expandable fireproof sheet. The first thermally expandable fireproof sheet comprises two or more thermally expandable fireproof sheets,
The two or more heat-expandable fireproof sheets are inserted on the back plate side inside the outlet box with the side surfaces of the two or more heat-expandable fireproof sheets facing each other. The fire prevention structure of the outlet box described in 1. The first thermally expandable fireproof sheet comprises two or more thermally expandable fireproof sheets,
The two or more thermally expandable fireproof sheets include a thermally expandable fireproof sheet (A) having a low thermal expansion start temperature and a thermally expandable fireproof sheet (B) having a high thermal expansion start temperature,
The low thermal expansion start temperature thermal expansion fireproof sheet (A) starts expanding at a lower temperature than the high thermal expansion start temperature thermal expansion fireproof sheet (B),
With reference to the direction perpendicular to the back plate of the outlet box, the thermally expandable fireproof sheet (A) having the low thermal expansion start temperature and the thermally expandable fireproof sheet (B) having the high thermal expansion start temperature are (A), (B )
The low thermal expansion start temperature thermal expansion fireproof sheet (A) is disposed on the side opposite to the back plate side inside the outlet box,
The fireproof structure for an outlet box according to any one of claims 1 to 4, wherein the heat-expandable fireproof sheet (B) having the high thermal expansion start temperature is disposed on the back plate side inside the outlet box. The first thermally expandable refractory sheet is formed by laminating at least a thermally expandable refractory layer (a) having a low thermal expansion start temperature and a thermally expandable refractory layer (b) having a high thermal expansion start temperature,
The thermally expandable refractory layer (a) having the low thermal expansion start temperature corresponds to the thermal expandable refractory sheet (A) having the low thermal expansion start temperature,
The fireproof structure for an outlet box according to claim 5, wherein the heat-expandable fireproof layer (b) having the high thermal expansion start temperature corresponds to the heat-expandable fireproof sheet (B) having the high thermal expansion start temperature. The wire cables are inserted through the inside of a flexible conduit tube with a cylindrical fixture at the end,
A cylindrical fixed receiver is installed in the insertion hole of the outlet box,
A cylindrical fixture installed at the end of the flexible conduit is fitted to a cylindrical fixture installed in the insertion hole of the outlet box,
A switchboard is installed on the support frame,
The wire cables inserted through the inside of the flexible conduit are introduced into the outlet box and connected to the switchboard,
The switchboard includes at least one selected from the group consisting of a wired communication outlet, a power outlet, a power switch, a power breaker, a power indicator, and an information display device,
The switchboard and the support frame are covered from the outside of the wall by a decorative plate, and a power outlet, a power switch, and a power breaker of the switchboard can be operated through the opening of the decorative plate, The fire prevention structure for an outlet box according to any one of claims 1 to 6, wherein the indicator lamp and the information display device can be visually recognized. A step (1) of installing an outlet box having a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate on the wall with the opening side of the outlet box facing the wall;
A step (2) of inserting an electric cable into an insertion hole formed in at least one of a back plate and a side plate of the outlet box;
Providing a through hole in the wall at a position where a part or all of the through hole of the wall and a part or all of the opening of the outlet box overlap with each other on the basis of the vertical direction of the wall (3) When,
Inserting the first thermally expandable fireproof sheet into the back plate inside the outlet box (4);
Installing a second thermally expandable fireproof sheet on the inner periphery of the through hole in the wall;
A construction method of a fire-protection structure of an outlet box having at least
When carrying out the step (1), a gap is installed between the wall and the outlet box,
The construction method of the fire-protection structure for an outlet box, wherein the step (4) and the step (5) are performed in random order after the step (1) is performed. Installing the support frame outside the through hole of the wall opposite to the side where the outlet box is installed;
A mortar plate having the opening portion installed in an outlet box, which is a detachable combination of an outlet box body and a mortar plate having an opening portion;
The support frame,
A step (7) of detachably connecting the connecting member inserted through the through-hole of the wall;
Have
When the second thermally expandable refractory sheet in the step (5) is installed on the inner periphery of the through hole of the wall, the end of the second thermally expandable refractory sheet is at the opening of the plate. The construction method of the fire prevention structure of an outlet box according to claim 8, wherein the fire prevention structure is installed. In the step (4), a first thermally expandable fireproof sheet composed of two or more thermally expandable fireproof sheets is inserted on the back plate side inside the outlet box,
The construction method of the fire-protection structure for an outlet box according to claim 8 or 9, which is a step of making the side surfaces of the two or more thermally expandable fireproof sheets face each other. In the step (4), the thermally expandable refractory sheet (B) having a high thermal expansion start temperature is inserted into the back plate inside the outlet box, and then the thermal expandable refractory sheet (A) having a low thermal expansion start temperature is By inserting the outlet box inside the back plate side of the outlet box, the thermal expansion fireproof sheet (A) having the low thermal expansion start temperature in the order of (A) and (B) with respect to the direction perpendicular to the back plate of the outlet box. It is disposed on the side opposite to the back plate side inside the outlet box, and the thermally expandable fireproof sheet (B) having the high thermal expansion start temperature is disposed on the back plate side inside the outlet box,
The thermal expansion fireproof sheet (A) having the low thermal expansion start temperature starts expansion at a temperature lower than that of the thermal expansion fireproof sheet (B) having the high thermal expansion start temperature. Method of fire prevention structure of the outlet box of the. For a wall having a through hole, the outlet box is installed so as to cover the through hole,
The outlet box has a space surrounded by a back plate and a side plate joined to the outer periphery of the back plate, and is installed on the wall with the opening side of the outlet box facing the wall,
There is a gap between the wall and the outlet box,
For the structure of the outlet box in which the electric cables are inserted through the insertion hole formed in at least one of the back plate and the side plate of the outlet box,
Insert the first thermally expandable fireproof sheet on the back plate side inside the outlet box,
A fireproof reinforcement method for the structure of an outlet box, wherein a second thermally expandable fireproof sheet is installed on the inner periphery of the through hole of the wall.