KR101839310B1 - Material for blocking heat conduction and a fire door - Google Patents

Abstract

The present invention relates to a conduction blocking material, and a fireproof door. That is, the present invention relates to the conduction blocking material and the fireproof door, which can form the conduction blocking material around between an inner panel and an outer panel of the fireproof door to block thermal conduction. More specifically, the fireproof door comprises: the inner panel (100) forming an inner surface of the fireproof door, and formed by steel sheets; the outer panel (200) forming an outer surface of the fireproof door, and formed by the steel sheets; and the conduction blocking material (300) coupled to an edge between the inner panel and the outer panel, formed in a bar shape, and formed of the compound of claim 1.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material for blocking heat conduction and a fire door,

The present invention relates to a conduction barrier material and a fire door, which is capable of preventing heat conduction by forming a conduction barrier material around the inner panel of the fire door and the outer panel.

In Patent Application 001, upper, lower, left, and right engaging portions formed on the front surface of the inner panel are fitted to upper, lower, left, and right engaging ends formed on the back surface of the outer panel, So that the inner and outer panels can be quickly joined to improve the workability and the inner and outer panels can be joined without welding to provide a color steel plate with various patterns and colors And a method of manufacturing the same.

The fire door is provided with an outer plate (20) and an inner plate (30), and has a fixing part (22) bent at one side, An outer plate 20 formed on the other side and having a side engaging portion 21 bent inward and having an engaging groove 33; An inner plate 30 having an engaging portion 31 having a side fixing portion 32 bent at one side thereof and a coupling protrusion 31a formed at an inner side at a predetermined interval on the other side; One side fixing portion 22 of the outer plate 20 and one side fixing portion 32 of the inner plate 30 are coupled to each other and the coupling groove formed in the other side coupling portion 21 of the outer plate 20 33 of the inner plate 30 are inserted into the coupling protrusions 31a of the inner plate 30 so as to prevent detachment of the coupling portion when the product is in use.

The patented invention includes a reinforcing frame (20) comprising vertical frames (22) on both sides and upper and lower horizontal frames (21); A rear plate 12 whose upper and lower ends are seamed on a rear outer wall 211 'of the transverse frame 21 of the reinforcing frame 20 and on which the reinforcing frame 20 is built; The upper and lower ends of the bending pieces 111 and 111 'at both ends of the reinforcing frame 20 are connected to both side wings 121 and 121' of the rear plate 12, A front plate 11 seamed to be joined to the back plate 12 and the reinforcing frame 20; And a honeycomb-shaped intermediate member 60 disposed between the front and rear plates 11 and 12. The rear surface 11b of the front plate 11 is bent toward the rear surface The wings 121 and 121 'of the plate 12 and the front outer wall 222 of the longitudinal frame 22 of the reinforcing frame 20 and the upper and lower ends of the front and rear plates 11 and 12 are seamed The front and rear outer walls 211 and 211 'of the frame 20 are coated with the heat-conduction preventing flame retardant packing 30 and the front and rear outer walls 211 and 211' The support plate 70 is fixed between the rear inner walls 211 and 211 'so that the windshield 80 can be installed around the fire doors extending from both sides of the fire door to the upper and lower sides, Proof fire-proof door (30).

The patent invention 004 discloses a door 1 in which a front plate 11 and a back plate 12 made of an iron plate having a predetermined width and a width are combined and a heat insulating material 13 is filled in the front plate 11 and the back plate 12; And a door frame 2 formed of a door frame 2 rotatably coupled to the door 1 and having a step portion 21 formed on an inner side of the door 1 in contact with an edge of the door 1, A), a door frame wing (21b) protruding from a step (21) of the door frame (2) at a predetermined distance from the front; A door recess 11a having a predetermined depth formed in an inner edge of the door 1 so that the door frame 21b can be inserted when the door 1 is closed; A door wing 12a formed at an end of the door recess 11a and configured to bend and protrude from the back plate 12 of the door 1; A door frame recess 21a formed at a predetermined interval between the step portion 21 and the door frame portion 21b of the door frame 2 so that the door flap portion 12a can be inserted when the door 1 is closed, The present invention provides a fire door having a fire door.

KR 10-0766339 B1 (Registered on October 5, 2007) KR 10-0951820 B1 (registered on April 01, 2010) KR 10-1311242 B1 (registered on September 16, 2013) KR 20-0366078 Y1 (Registered on October 19, 2004)

The present invention relates to a conduction barrier material and a fire door, which is capable of preventing heat conduction by forming a conduction barrier material around the inner panel of the fire door and the outer panel.

In order to solve the problems of the prior art, the present invention is an invention of a conduction barrier material, which is formed by the synthesis of glass fiber, phenolic resin and calcium carbonate in the conduction barrier material.

The present invention relates to a fire door, comprising: an inner panel (100) which forms an inner surface of a fire door and is formed of a steel plate, an outer panel (200) which forms an outer surface of the fire door and is formed of a steel plate, And a conduction barrier 300 formed in the shape of a bar and formed of the above-described composite, which is joined to an edge between the inner panel and the outer panel.

The fire door of the present invention includes a reinforcing bar (400) coupled to a side surface of the conduction barrier in the previously described invention.

The fire door of the present invention is characterized in that it comprises a coupling groove (310) formed at one side of the conduction barrier and inserted with the reinforcing bar, and a protruding step (320) protruding from the other side of the conduction barrier do.

In the fire door according to the present invention, the conductive barrier is formed by an engaging projection protruding from one side, an engaging groove (310) into which the reinforcing bar is inserted, And protruding protrusions 330 formed in the middle portion of the conduction barrier, and fitting grooves 340 formed inwardly of the intermediate portion of the conduction blocking material and interposed between the inner panel and the outer panel.

According to the fire door of the present invention, in the above-described invention, the conduction barrier is formed by an engaging projection protruding from one side, an engaging groove (310) into which the reinforcing bar is inserted, A fitting groove 340 into which the outer panel is fitted, and a rivet coupling groove 350 formed in the other side of the conduction barrier.

The present invention forms a conduction barrier around an inner panel and an outer panel of a fire door, and separates the inner panel and the outer panel from each other to block heat conduction.

The conductive barrier material and the door of the fire door of the present invention have a plate-like reinforcing band formed between the conduction barrier and the heat insulating material to improve durability. The present invention has a firm fixation force and has an effect of preventing warping when an external force is applied. In the present invention, the inner panel and the outer panel are combined with the conduction barrier in a complex structure, thereby enhancing the strength of the coupled portion and preventing the locally generated deformation, thereby prolonging the service life.

1 is a perspective view showing a fire door of the present invention.
FIG. 2 and FIG. 3 are plan sectional views showing the construction of the fire door of the present invention. FIG.
4 is an exemplary view showing another embodiment of a fire door according to the present invention;
5 is an exemplary view showing various embodiments of a reinforcing bar according to the present invention.
6 is an exemplary view showing another embodiment of the conduction barrier according to the present invention.
7 is an exemplary view showing a coupling structure of a panel and a conductive barrier according to the present invention.
8 is an exemplary view showing another embodiment of a panel and a conductive barrier member coupling structure according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Example 1-1] The present invention relates to a conduction barrier material, which is formed by the synthesis of a glass fiber, a phenol resin and calcium carbonate as a conduction barrier material.

The present invention relates to a material for blocking heat conduction, and in order to realize this, a glass fiber, a phenol resin and calcium carbonate are mixed and formed.

[Example 1-2] Conductive barrier material of the present invention In the example 1-1, the glass fiber is 50 to 70% by weight, the phenolic resin is 20 to 40% by weight, the calcium carbonate is 5 to 10% by weight %;

The glass fiber is a mineral fiber in which a molten glass is formed into a fiber shape. The glass fiber serves as a base layer and increases dimensional stability and heat resistance. When the content is less than 50% by weight, the effect on dimensional stability and heat resistance is insignificant. When the content is more than 70% by weight, the rigidity of the product is weakened.

The phenol resin is classified into a resol-type phenol resin and a novolac-type phenol resin, and any one of them may be used in the present invention. The phenolic resin acts to prevent the disturbance of the product shape and is used to improve the tackiness. The phenol resin is contained in an amount of 20 to 40% by weight. When the content is less than 20% by weight, moldability is deteriorated. When the content is more than 40% by weight, mechanical properties and thermal properties are deteriorated.

The calcium carbonate is a carbonate of calcium and is present in marble, calcite, limestone, chalk, gypsum, shell, egg shell, coral and the like. The calcium carbonate is added to increase the heat resistance. Calcium carbonate is contained in an amount of 5 to 10% by weight. If the content is less than 5% by weight, the heat resistance is not affected. If the content is more than 10% by weight, mechanical strength is weakened.

[Example 1-3] Conductive barrier material of the present invention In Example 1-1, the glass fiber includes those which are substituted with carbon fiber or aramid fiber.

In order to improve the flame retardancy of the conduction barrier material, carbon fiber or aramid fiber is used instead of glass fiber. Or may be replaced with a material that exhibits the same purpose and effect as the substitution.

[Example 1-4] Conductive barrier material of the present invention In Example 1-1, the above-mentioned calcium carbonate includes those which are converted into an inorganic material and used.

Minerals such as talc, mica stone, wollastonite, and feldspar can be used to increase the heat resistance of the product. Or may be substituted with minerals having the same purpose and effect.

[Example 2-1] The present invention relates to a fire door, comprising: an inner panel (100) which forms an inner surface of a fire door and is formed of a steel sheet; And a conduction barrier 300 formed of a composite material of Example 1-1 and formed in a bar shape and joined to an edge between the inner panel and the outer panel.

Conventional fire doors are made of metal and are made from a combination of an inner panel and an outer panel. The two panels are structurally contacted. This serves to conduct the heat generated on one side and diffuse it to the other side. To prevent such heat conduction, the inner panel and the outer panel must be separated by a conduction barrier. In addition, the inner panel and the outer panel combined with the conduction barrier must secure the structural safety of the fire door.

 [Embodiment 2-2] In the fire door 2-1 of the present invention, a plurality of door hinges 500, one side of which is coupled to the outer panel or the inner panel, and the other side of which is coupled to the door frame.

 [Embodiment 2-3] In the fire door 2-1 of the present invention, the handle 600 is formed on one side of the inner panel and the outer panel.

The fire door is coupled to the inside of the door frame and is rotated at a certain angle from the door frame by the door hinge. The user can open and close the door by the handle.

 [Example 2-4] In the fire door 2-1 of the present invention, the conductive barrier material includes those formed of the materials of Examples 1-1 to 1-3.

The conductive barrier material is excellent in productivity and has a heat conduction blocking effect. For this, a composite composition is prepared by mixing, the glass fiber forms a base layer, the phenol resin serves as a binder for molding, and the calcium carbonate exhibits heat resistance performance.

[Embodiment 2-5] In the fire door 2-1 of the present invention, the interior material 700 is filled in a space between the inner panel and the outer panel.

A first interior material formed of an organic material and formed of a foam board; a second interior material formed on one surface of the first interior material and formed of an inorganic material and formed of a foam board; And a third interior material formed of an inorganic material and formed of a foam board.

The building comprises a door for facilitating the movement of people and a panel for forming the wall. These structures are required to have a heat shielding function to block heat when a fire occurs, and an insulation performance to reduce the temperature change, and additionally, to prevent condensation and to have fire resistance to withstand a certain time flame. It provides a standard with strict standards and can only be used if it meets the criteria. However, since the adiabatic and differential thermal performance have opposite effects, it is difficult to simultaneously satisfy the adiabatic and differential thermal characteristics. The present invention relates to a fireproof interior material satisfying heat insulation performance and simultaneously satisfying heat shield performance.

The present invention provides a fire-retardant interior material that can form a first heat-insulating material with a high heat-insulating performance, and a second heat-insulating material and a third heat-insulating material having high heat- do.

The fire-retarding inner material forms a second inner material and a third inner material on the outside to preferentially block the flame and improve the fire resistance. On the other hand, the first interior material in the second interior material and the third interior material enhances the heat insulation performance to block heat.

The first inner material is made of an organic material, and the second inner material and the third inner material are made of an inorganic material. The first to third interior materials are formed into a foam shape and are made into a plate shape.

The organic material and the inorganic material are formed of a plurality of foam boards, and many of them are formed in a laminated shape. The thickness of the organic material forms 70% of the total thickness, and the thickness of the inorganic material forms 30% of the total thickness.

[Example 2-6] In Example 2-5, the first interior material includes those formed of phenol foam.

The first interior material to the third interior material may be formed of a foam board. The first interior material is formed of a phenolic foam. The phenolic foam is a material obtained by foaming and curing a phenolic resin. The first interior material is excellent in heat insulation performance, has a high heat resistance value, Lt; / RTI > The foam pores in the phenol foam have a diameter ranging from 0.03 mm to 0.1 mm, preferably 0.05 mm. The foam pores are formed as independent foams. The foamed pores formed as independent foams can improve the heat insulating performance and can suppress gas emission.

[Example 2-7] In Example 2-5, the second and third interior materials were made of mineral wool fiber, glass wool fiber, ceramic fiber, carbon fiber, vegetable fiber, polyester, expanded polystyrene, urethane board, Phenol foam, or a vacuum insulation material obtained by vacuum-treating a core material in an aluminum film.

The second and third inner materials are selected from among mineral wool fibers, glass wool fibers, ceramic fibers, carbon fibers, vegetable fibers, polyester, expanded polystyrene, urethane board, phenol foam, . Carbon fiber is made of carbon fiber made of cellulosic acrylic fiber, vinylon or phytite, and equivalent object can be used. Vegetable fiber uses hemp fiber and equivalent materials can be used.

[Example 2-8] In Example 2-5, a first binder formed between the first inner material and the second inner material, and a second binder formed between the first inner material and the third inner material do.

The first binder and the second binder are used in combination of the first interior and the second interior material formed in the shape of a plate and the combination of the first interior material and the third interior material. The first and second binders form a chemical bond by joining two boards formed of foam, and do not generate toxic substances in case of fire, and must be made of a material having high fire resistance.

To accomplish this, the first and second binders may comprise 55 to 97.4% by weight of one or more alkyl (meth) acrylate monomers wherein the alkyl group contains 4 to 14 carbon atoms and one containing a nitrogen or oxygen containing heterocyclic ring (Meth) acrylate polymer comprising recurring units derivable from a monomer composition comprising from 2.5 to 40% by weight of at least one ethylenically unsaturated monomer and from 0.1 to 5% by weight of at least one polar comonomer, 1 to 60 parts by weight of at least one hydrogenated tackifier per 100 parts by weight of the material; And 1 to 20 parts by weight of microspheres per 100 parts by weight of the reference material.

As another embodiment, it includes a material in which a large amount of carbon dioxide is generated at the time of oxidation. As a specific example, sodium bicarbonate and a binder are synthesized and then the synthesized binder is used as a first and a second binder. Two foam sidewalls are glued by the binder, and sodium hydrocarbons are formed on the adhesive surface after bonding. Sodium hydrocarbons generate a large amount of carbon dioxide during combustion, which can lead to digestion.

[Example 2-9] In the fireproof interior material of the present invention, in Examples 2-5, the second interior material and the third interior material comprise a coating layer formed of a flame retardant material.

The second and third interior materials are formed of an inorganic fibrous structure and include a plurality of pores between the fibers. The fibrous structure of the second and third interior materials is coated with an inorganic foamed flame retardant. The inorganic foamed flame retardant is present as a coating layer at room temperature, but when it reaches a temperature of 230 ° C, it is foamed to shield the fiber layer.

[Example 2-10] In Example 2-9, the flame retardant was composed of sodium silicate consisting of silicon dioxide and sodium oxide, carboxymethyl cellulose sodium, ammonium monophosphate, sodium phosphate, and silicone or modified silicone (Polyvinyl Methyle Silicon Rubber).

The second and third interior materials made of fiber structure are coated with a flame retardant material. Since the impregnation coating method affects the method of manufacturing the second and third interior materials, . Specifically, in the impregnation coating method, there is a specific condition that allows heating to dry only the water of the flame retardant aqueous solution and, after drying, to be foamed by the coated flame retardant coating layer. Therefore, this corresponds to the manufacturing method that affects the object.

In the squeeze step, the two rollers squeeze the second and third inner materials to squeeze the aqueous flame retardant solution contained in the inner material fiber layer. The rollers may be made of a plurality of combinations. In the drying step, the interior material is received in a closed space, and is rapidly dried using a microwave. The enclosed space includes a shield to prevent external emission of the microwave.

[Example 3-1] In the fire door 2-1 of the present invention, a reinforcing bar 400 coupled to a side surface of the conduction barrier material is included.

The inner and outer panels of the present invention are separate. Therefore, a member for reinforcing the strength of the inner panel and the outer panel separated from each other is needed. To this end, a reinforcing bar formed of a metal plate is bonded between the conductive barrier material and the inner material to improve durability.

[Example 3-2] In the fire door 3-1 according to the present invention, the reinforcing bar coupling protrusion 311 is formed at one side of the conduction barrier material.

A reinforcing bar is inserted at an accurate position, and a coupling protrusion for inserting the reinforcing bar is formed at one side of the conduction barrier so that the reinforcing bar is not separated from the conduction barrier. Since the reinforcing bar is formed of metal, the assembling rigidity of the conduction barrier can be improved.

[Embodiment 3-3] In the fire door 3-1 of the present invention, a protruding step 320 is formed on the other side of the conduction barrier.

 [Example 3-4] In the fire door 3-1 of the present invention, the protruding step thickness is the same as the thickness of the inner panel and the outer panel, and the edges of the inner panel and the outer panel form the bent portions 110 and 210, The bending portion includes being coupled to both sides of the protruding step.

The corner of the fire door combines with the conduction barrier, and the inner panel and the outer panel associated with the conduction barrier must form the same plane.

[Embodiment 3-5] In the fire door 3-4 of the present invention, an engagement fastener 800 which joins the inner panel, the conduction barrier and the reinforcing bar, and joins the outer panel, the conduction barrier and the reinforcing bar.

The inner panel, the outer panel, the reinforcement, and the barrier material shall be securely and integrally fixed. To this end, the fastening fasteners form through-holes passing through the respective panels (inner panel and outer panel), the conduction barrier, and the reinforcing bars, and the through-holes fasten the fastening fasteners. The engagement fastener is made of any one selected from a rivet and a bolt. Or may be replaced with a fastening member which exhibits the same purpose and effect.

[Embodiment 3-6] In the fire door 3-1 of the present invention, the reinforcing bar includes a plate material.

[Embodiment 3-7] In the fire door 3-1 of the present invention, the reinforcing bar includes a plate member whose both ends are bent.

In order to ensure the ease of joining of the interior material, both sides of the interior material form a step, which is inserted into the bend of the reinforcement. At this time, the size of the interior material step is formed to be equal to the thickness of the reinforcing bar bent portion.

[Embodiment 3-8] In the fire door 3-7 of the present invention, a rebound portion formed in one of the bent portions is included.

In order to improve the binding force between the interior material and the reinforcing bar, one of the bent portions of the reinforcing bar forms a second bent bent portion. The rebound portion is engaged with a groove formed in the surface of the lining material. In case of fire, the interior material is deformed, and the interior material is to be joined to the groove so that the deformed interior material is not detached from the inside of the fire door.

[Example 3-9] In the fire door 3-6 or 3-8 of the present invention, the thickness of the reinforcing bar is formed to be 1 mm to 3 mm.

If the thickness of the reinforcing bar is less than 1 mm, there is no strength reinforcement effect on the panel. If it exceeds 3 mm, the contact area with the interior material is reduced.

[Example 4-1] In the fire door 2-1 according to the present invention, a connecting groove (310) formed at one side of the conduction barrier and into which the reinforcing bar is inserted, a protruding step formed at the other side of the conduction barrier 320).

The joining groove is formed to join the reinforcing bar to the side surface of the conduction barrier. The combination of the conduction barrier and the reinforcing bar prevents the deformation of the reinforcing bar due to the impact and improves the durability. Meanwhile, the inner panel and the outer panel of the fire door must be separated from each other to prevent heat conduction. Therefore, the projecting step of the conduction barrier is coupled between the bent portions formed at the ends of the inner panel and the outer panel, respectively.

[Example 4-2] In the fire door 4-1 of the present invention, the protruding bar 360 formed on the other side of the conduction barrier, formed in the same direction as the protrusion step, and extended to the other corner of the conduction barrier.

The fire door forms a protruding projection, and the door frame forms a groove in which the projection is received. The projections and grooves have the purpose of improving the sealing effect. The protrusion is formed on the inner panel or the outer panel. The protrusion extends from the inner panel or the outer panel. The protrusion forms a space therein, and the protrusion bar is inserted into the space.

[Example 5-1] In the fire door 2-1 according to the present invention, the conduction barrier was formed by a coupling protrusion formed on one side, a coupling groove 310 into which the reinforcing bar was inserted, A protrusion protrusion 330 formed integrally with the inner panel, and a fitting groove 340 formed inwardly of the intermediate portion of the conduction barrier, the fitting groove being fitted to the inner panel and the outer panel.

Both the bending portions of the inner panel and the outer panel can be fitted into the fitting groove of the conduction barrier. Therefore, it has a firm fixing force and can prevent warping when an external force is applied. On the other hand, the conductive barrier disposed on the door hinge side can serve as a stopper. For this purpose, protruding protrusions are formed at one end of the other side of the conduction barrier. The projecting protrusion restricts a rotation angle of the fire door when the fire door is opened or closed.

[Embodiment 5-2] In the fire door 5-1 of the present invention, a lower step 370 formed on one side of the conduction barrier and formed by the thickness of the inner panel and the outer panel is included.

The inner panel and the outer panel are in the same horizontal plane as the conduction barrier. Therefore, in the structure in which the inner panel and the outer panel are fitted to the conduction barrier, a recessed step is formed on one side of the conduction barrier in order to form the same horizontal plane. The recessed step is formed to have a thickness corresponding to the inner panel and the outer panel.

[Example 6-1] In the fire door 2-1 according to the present invention, the conduction barrier was formed by a coupling protrusion formed on one side, the coupling groove 310 into which the reinforcing bar was inserted, And a rivet fastening groove 350 formed on the other side of the conduction blocking material. The rivet fastening groove 350 may be formed in the outer circumferential surface of the outer panel.

The inner panel and the outer panel may be of a composite structure in the conduction barrier. In order to achieve this, the inner panel is coupled to the outer surface of the conduction barrier material in a wrapping manner, and the outer panel is fitted to the conduction barrier material. Thus enhancing the strength of the bonded portion and preventing localized deformation, thereby prolonging the service life.

[Embodiment 6-2] In the fire door 6-1 of the present invention, a protrusion part 380 formed on the other side of the conduction barrier material and closely contacting the bending step 220 formed on one side of the outer panel.

[Embodiment 6-3] In the fire door 6-1 of the present invention, an extension protrusion 390 is formed on one side of the conduction barrier and has one end of the coupling protrusion protruding outwardly.

[Example 6-4] In the fire door 6-1 of the present invention, a bending cover 130 formed at one side of the inner panel and closely contacting the other side of the conduction barrier, And a bending step 220 fitted to the fitting groove.

Thereby more closely maintaining the adhesion between the inner panel and the outer panel to the conduction barrier. Further, the strength is increased to prevent the deformation from occurring, and the smoothness between the panels is made uniform. To this end, the bending cover of the inner panel is in close contact with the other side of the conduction barrier, and the bending step of the outer panel is fitted into the intermediate portion of the conduction barrier.

100: inner panel 110:
120: step 130: bending cover
200: outer panel 210:
220: Bending step 300:
310: engaging groove 311: engaging projection
320: projecting step 330: projecting projection
340: fitting groove 350: rivet fitting groove
360: protruding bar 370:
380: Pluggable part 390: Extension projection
400: Rib 500: Door hinge
600: Handle 700: Interior material
800: Combined fastener

Claims (6)

delete In the fire door,
An inner panel 100 forming an inner surface of the fire door and formed of a steel plate;
An outer panel 200 forming an outer surface of the fire door and formed of a steel plate;
A conduction barrier 300 formed in the form of a bar and formed of a compound of glass fiber, phenolic resin, and calcium carbonate, which is joined to an edge between the inner panel and the outer panel;
An engaging groove 310 formed at one side of the conduction barrier and into which the reinforcing bar is inserted;
And a protruding step (320) protruding from the other side of the conductive barrier.
delete delete The method of claim 2,
The conduction barrier is formed by a protrusion formed on one side, and an engaging groove (310) into which the reinforcing bar is inserted;
A protrusion protrusion 330 integrally formed on the other end of the conduction barrier;
And a fitting groove (340) recessed inwardly in an intermediate portion of the conduction barrier material and fitted to the inner panel and the outer panel, respectively.
The method of claim 2,
The conduction barrier is formed by a protrusion formed on one side, and an engaging groove (310) into which the reinforcing bar is inserted;
A fitting groove (340) recessed inwardly at an intermediate portion of the conduction barrier and fitted with the outer panel;
And a rivet fastening groove (350) formed on the other side of the conduction barrier.

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