Heat insulating door and refrigerator comprising the same

Abstract

To provide a heat insulating door that can facilitate automation of work, and a refrigerator comprising the same.SOLUTION: A heat insulating door comprises an outer plate 51, a reinforcing plate 57 provided on the side of a back surface of the outer plate 51, and a hot-melt adhesive material 58 for bonding the outer plate 51 and the reinforcing plate 57. The heat insulating door comprises a foam heat insulation material 55 foamed in situ, in a space facing the back surface of the outer plate 51. The outer plate 51 is a material capable of being deformed by pressure of in-situ foaming of the foam heat insulation material 55. The hot-melt adhesive material 58 is applied to an outer periphery of the reinforcing plate 57 between the back surface of the outer plate 51 and the reinforcing plate 57.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a heat-insulating door and a refrigerator equipped with the same. [Background technology]

[0002] It is known that when vacuum insulation material or the like is fixed to the back surface of the outer panel of a door made of steel plate or resin and foam insulation material is foam-filled inside the door, the outer panel will be deformed by the contraction force of the foam insulation material. This is because the contraction force is applied differently at the boundary of the vacuum insulation material, and marks along the boundary line remain on the surface of the outer panel. For this reason, a reinforcing plate is provided between the outer panel and the vacuum insulation material.

[0003] Incidentally, when filling and foaming foam insulation inside the door on the back surface of the exterior panel, if a gap is formed between the exterior panel and the reinforcing plate, the foam insulation will get into the gap and deform the exterior panel. Therefore, in Patent Document 1, the reinforcing plate is fixed to the back surface of the exterior panel with adhesive tape to prevent the formation of a gap between the exterior panel and the reinforcing plate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2023-44834 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, as described in Patent Document 1, when an adhesive tape is used, a gap is not formed between the outer panel and the reinforcing panel, but there is a problem that it is difficult to automate the work. [Means for solving the problem]

[0006] The insulated door of the present invention comprises an outer panel, an intervening member provided on the back side of the outer panel, and an adhesive that is in a fluid state when applied and bonds the outer panel and the intervening member. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a front view of a refrigerator according to a first embodiment. [Diagram 2] FIG. 2 is a front perspective view of the insulating door of the lower freezer compartment. [Diagram 3] FIG. 3 is an exploded perspective view of the insulating door of FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] FIG. 5 is an enlarged view of a main part of FIG. [Figure 6] 1 is a table showing the presence or absence of urethane penetration based on the thickness of the hot melt adhesive. [Figure 7] FIG. 2 is a front view of an insulated door with a hot melt adhesive applied thereto. [Figure 8] FIG. 11 is a front view of the insulating door of the second embodiment. [Figure 9] FIG. 11 is a front view of the insulating door of the third embodiment. [Figure 10] FIG. 11 is a cross-sectional view of an insulating door according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the following embodiment. First, the overall configuration of a refrigerator 1 according to this embodiment will be described.

[0009] FIG. 1 is a front view of a refrigerator 1 according to the first embodiment. As shown in FIG. 1, the refrigerator 1 has storage compartments in the following order from the top: a refrigerator compartment 2, an ice-making compartment 3, an upper freezer compartment 4, a lower freezer compartment 5, and a vegetable compartment 6. The insulated doors 2a and 2b for opening and closing the refrigerator compartment 2 are of the rotating type that rotate around a hinge (not shown). The insulated door 3a for opening and closing the ice-making compartment 3, the insulated door 4a for opening and closing the upper freezer compartment 4, the insulated door 5a for opening and closing the lower freezer compartment 5, and the insulated door 6a for opening and closing the vegetable compartment 6 are of the drawer type. The insulated doors 2a and 2b of the refrigerator compartment 2 are not limited to double doors (French doors) and may be single doors. The arrangement and number of the storage compartments and their insulated doors are not limited to the example in FIG. 1.

[0010] Although not shown, the insulated box of the refrigerator 1 includes an outer box made of steel plate and an inner box made of resin. A foam insulation material such as rigid urethane foam and a vacuum insulation material using glass wool are provided in the space formed by the outer box and the inner box, and each storage compartment inside the insulated box is insulated from the outside. The configuration of the insulated door of the refrigerator 1 will be described below. Types of insulation materials include fiber insulation materials (glass wool, rock wool, cellulose fiber, etc.) and foam insulation materials (urethane foam, phenol foam, etc.). Among foam insulation materials, urethane foam (rigid urethane foam) is often used as a foam insulation material that is foamed on site. Urethane is a compound having a urethane bond formed by the reaction of a polyol component and an isocyanate component.

[0011] To explain the configuration of the insulated door of the refrigerator 1, first, a drawer-type insulated door will be explained, taking the insulated door 5a of the lower freezer compartment 5 as a representative. Fig. 2 is a front perspective view of the insulated door of the lower freezer compartment, Fig. 3 is an exploded perspective view of the insulated door of Fig. 2, and Fig. 4 is a cross-sectional view taken along line IV-IV of Fig. 2. As shown in Figs. 2 to 4, the insulated door 5a includes an outer plate 51 provided on the front side (front side) to form a design surface, door frames provided on the upper and lower edges of the outer plate 51, an inner plate 54 (liner) provided on the back side (rear side) of the outer plate 51, and a foamed insulation material 55 foamed on site in a space Y surrounded by the outer plate 51, the door frame, and the inner plate 54. In addition to the foamed insulation material 55, the space Y also includes a vacuum insulation material 56 provided so as to face the surface of the outer plate 51, and a reinforcing plate 57 (intervening member) between the outer plate 51 and the vacuum insulation material 56. Details of the reinforcing plate 57 will be described later. In most cases, foaming on site is performed (constructed) on site at a manufacturing plant for refrigerators (insulated doors).

[0012] The outer plate 51 is made of a material that can be deformed by the pressure of the on-site foaming of the foam insulation material 55, and is formed of, for example, a thin steel plate. The outer plate 51 is bent backward (rearward) at the left and right curved portions 511.

[0013] The door frame is made of resin, and as shown in Fig. 3, has upper frame portion 52 attached to the upper side of outer plate 51, and lower frame portion 53 attached to the lower side of outer plate 51. Upper frame portion 52 is formed with handle portion 521 on which a user places his / her hand when opening or closing the door.

[0014] Vacuum insulation material 56 is, for example, a core material such as glass wool sealed with a laminate film having gas barrier properties to reduce the pressure inside. Also, the material is not limited to vacuum insulation material 56, and may be, for example, a plate-shaped insulation material in which a core material (pre-foamed foam insulation material) made of foam insulation material such as rigid urethane foam molded into a flat plate shape is covered and sealed with a laminate film having gas barrier properties. Among the insulation materials used in refrigerators, vacuum insulation material 56 and plate-shaped insulation materials do not fall under the category of foam insulation material foamed on site.

[0015] The inner plate 54 is formed by injection molding a resin such as polypropylene, and is fixed to the rear sides of the left and right folded parts of the outer plate 51 and the rear sides of the upper frame part 52 and the lower frame part 53 to form a space Y inside the insulated door 5a as shown in Fig. 4. A recess 542 is provided on the edge of the inner plate 54 so as to surround the four sides, top, bottom, left and right, and a packing (not shown) is attached to this recess 542. Therefore, when the insulated door 5a is closed, the packing comes into contact with the front opening of the lower freezer compartment 5, thereby sealing the lower freezer compartment 5.

[0016] Incidentally, after the filling process of the foam insulation material 55, the foam insulation material 55 thermally shrinks and the outer plate 51 is pulled via the vacuum insulation material 56. For this reason, if the vacuum insulation material 56 is directly attached to the outer plate 51 made of a steel plate, the unevenness on the surface of the vacuum insulation material 56 or the edge of the vacuum insulation material 56 may appear as a mark on the surface of the outer plate 51, which may result in poor appearance. Therefore, in this embodiment, as shown in FIG. 4, a reinforcing plate 57 is disposed between the outer plate 51 and the vacuum insulation material 56. The material of the reinforcing plate 57 may be the same material as that of the outer plate 51 (steel plate in this embodiment). By using the reinforcing plate 57, the plate thickness of the outer plate 51 is substantially increased, and the strength of the outer plate 51 is improved, so that the outer plate 51 is less likely to deform even when pulled due to the thermal shrinkage of the foam insulation material 55, and marks due to distortion are less likely to appear on the surface of the outer plate 51. Such marks may appear not only when the outer plate 51 is a steel plate, but also when the intervening member is a resin. This problem may also occur when the outer panel 51 is made of glass as an intervening member.

[0017] FIG. 5 is an enlarged view of a main portion of FIG. As shown in FIG. 5, the reinforcing plate 57 is placed so as to face the back surface of the outer plate 51, and a hot melt adhesive 58 (an adhesive in a fluid state when applied) is applied between the back surface of the outer plate 51 and the reinforcing plate 57, thereby adhering and fixing the reinforcing plate 57 to the outer plate 51. The hot melt adhesive 58 (adhesive) is solid at room temperature and is heated and melted to become fluid when applied. After application, the hot melt adhesive 58 is left in a room temperature environment and cooled, whereby the hot melt adhesive 58 solidifies and the reinforcing plate 57 is fixed to the outer plate 51. For example, a polyamide-based hot melt adhesive 58 is used. Whether the adhesive is "fluid when applied" (whether it is hot melt or not) can be easily judged after the fact by analyzing the adhesive used.

[0018] In addition, the hot melt adhesive 58 is formed up to the edge 57a (edge ​​of the interposed member) of the reinforcing plate 57. This makes it possible to prevent the foamed insulating material 55 (urethane) from entering the gap between the outer plate 51 and the reinforcing plate 57.

[0019] FIG. 6 is a table showing the presence or absence of urethane penetration based on the thickness of the hot melt adhesive. However, when the reinforcing plate 57 is fixed to the outer plate 51 using the hot melt adhesive 58, a gap is generated between the outer plate 51 and the reinforcing plate 57. If this gap is wide, the foamed insulation material 55 (urethane) may enter the gap, causing a problem in the appearance of the outer plate 51. Therefore, when the outer plate 51 and the reinforcing plate 57 are fixed with the hot melt adhesive 58, the presence or absence of urethane intrusion when the thickness T of the hot melt adhesive 58 in a solidified state is changed was examined. As a result, as shown in FIG. 6, it was confirmed that urethane intrusion occurs when the thickness T of the hot melt in a solidified state is 0.16 mm, and that urethane intrusion occurs also when the thickness T is 0.12 mm. It was also confirmed that no urethane intrusion occurs when the thickness T of the hot melt in a solidified state is 0.09 mm. In this way, it was confirmed that the intrusion of the hot melt adhesive 58 into the gap between the outer plate 51 and the reinforcing plate 57 can be suppressed by setting the thickness T of the hot melt adhesive 58 in a solidified state to 0.1 mm or less.

[0020] In addition, a coating device equipped with a spiral type nozzle can be used as a method for coating the hot melt adhesive 58. The spiral type is a method in which the hot melt adhesive 58 is coated while rotating in a spiral shape. By using such a spiral type, coating can be performed with less thickness unevenness than with a normal nozzle type or mist type. In addition, by using the spiral type, the coating thickness can be reduced to about 0.1 mm, which is thinner than with a normal nozzle type or mist type. In other words, if the coating thickness of the hot melt adhesive 58 during coating can be reduced to about 0.1 mm, the thickness T in the solidified state can be reduced to 0.1 mm or less.

[0021] FIG. 7 is a front view of an insulating door coated with hot melt adhesive. 7, the hot melt adhesive 58 is applied in a straight line from the left end to the right end along the upper and lower edges of the reinforcing plate 57. In this manner, the hot melt adhesive 58 is applied to the outer periphery of the reinforcing plate 57. This makes it possible to prevent the foamed insulation 55 (urethane) from entering the gap between the outer plate 51 and the reinforcing plate 57 from the top or bottom of the reinforcing plate 57, even if the space Y (see FIG. 4) is filled with the foamed insulation 55 (see FIG. 4), and thus makes it possible to suppress defects in the appearance of the outer plate 51.

[0022] As described above, the heat-insulating door 5a of the first embodiment includes the outer plate 51, the reinforcing plate 57 (intervening member) provided on the back side of the outer plate 51, and the hot melt adhesive 58 that bonds the outer plate 51 and the reinforcing plate 57. By using the hot melt adhesive 58, it becomes easier to automate the installation work compared to the conventional method using adhesive tape.

[0023] In the first embodiment, the space Y facing the back surface of the outer panel 51 has foamed insulation material 55 foamed on site. The outer panel 51 has a material that can be deformed by the pressure of foaming on site of the foamed insulation material 55. The hot melt adhesive 58 is applied between the back surface of the outer panel 51 and the reinforcing plate 57. This allows automation of the attachment of the reinforcing plate 57 to the outer panel 51 and the insulated door 5a made of steel plate or resin.

[0024] In the first embodiment, the thickness of the hot melt adhesive 58 in a solidified state is 0.1 mm or less. This makes it possible to prevent the foam insulation material 55 (urethane) from entering the gap between the outer plate 51 and the reinforcing plate 57 when the foam insulation material 55 is filled.

[0025] Moreover, in the first embodiment, the space Y facing the back surface of the outer panel 51 has a foamed insulation material 556 foamed on site. The outer panel 51 has a material that can be deformed by the pressure of the foamed insulation material 55 foamed on site. The hot melt adhesive 58 is applied to the outer periphery of the reinforcing plate 57 between the back surface of the outer panel 51 and the reinforcing plate 57. This makes it possible to suppress the intrusion of the foamed insulation material 55 (urethane) into the gap between the outer panel 51 and the reinforcing plate 57.

[0026] In the first embodiment, the hot melt adhesive 58 is applied up to the edge of the reinforcing plate 57 (intervening member). This makes it possible to prevent the foamed insulating material 55 (urethane) from penetrating into the edge between the rear surface of the outer plate 51 and the reinforcing plate 57.

[0027] FIG. 8 is a front view of the insulating door of the second embodiment. As shown in Fig. 8, in the insulating door 5b of the second embodiment, the hot melt adhesive 58 is applied to the entire outer periphery of the reinforcing plate 57 between the back surface of the outer plate 51 and the reinforcing plate 57. In other words, the hot melt adhesive 58 is formed in a rectangular frame shape without any gaps. This makes it possible to prevent the foamed insulating material 55 from entering the gap between the outer plate 51 and the reinforcing plate 57. In addition, by applying the hot melt adhesive 58 up to the edge of the reinforcing plate 57, it is possible to prevent the foamed insulating material 55 (urethane) from entering the edge between the back surface of the outer plate 51 and the reinforcing plate 57.

[0028] However, if the hot melt adhesive 58 is applied seamlessly to the entire outer periphery of the reinforcing plate 57, air will be trapped inside the hot melt adhesive 58, and the air will expand or contract due to heat, deforming the outer plate 51 and causing a problem of poor appearance. In addition, if the outer plate 51 is made of steel, the center tends to be convex toward the outside (front side) due to bending, which makes it easy for air to get in. Therefore, the above-mentioned problem can be solved by using the insulating door 5c of the third embodiment instead of the insulating door 5b of the second embodiment. Figure 9 is a front view of the insulating door of the third embodiment.

[0029] As shown in Fig. 9, in the insulating door 5c of the third embodiment, the hot melt adhesive 58 is applied to the entire outer periphery of the reinforcing plate 57 between the back surface of the outer panel 51 and the reinforcing plate 57, and is also applied to the center between the back surface of the outer panel 51 and the reinforcing plate 57. Note that the hot melt adhesive 58 may be applied to the entire surface of the reinforcing plate 57 between the back surface of the outer panel 51 and the reinforcing plate 57. This prevents air from being trapped inside the reinforcing plate 57, thereby suppressing deformation of the outer panel 51 due to expansion and contraction of air.

[0030] FIG. 10 is a cross-sectional view of the insulating door of the fourth embodiment. As shown in Fig. 10, the insulating door 5d of the fourth embodiment is provided with a vacuum insulating material 56 on the back surface of a reinforcing plate 57. The vacuum insulating material 56 and the reinforcing plate 57 are bonded together using a hot melt adhesive 59. The same type of hot melt adhesive 59 as the above-mentioned hot melt adhesive 58 can be used. This makes it easier to automate the work compared to the conventional case in which double-sided tape is used.

[0031] Note that hot melt adhesive 59 is provided between reinforcing plate 57 and vacuum insulation material 56, and since reinforcing plate 57 prevents deformation of outer plate 51, a gap through which foam insulation material 55 can penetrate may be formed between vacuum insulation material 56 and reinforcing plate 57. Also, since hot melt adhesive 59 is provided between vacuum insulation material 56 and reinforcing plate 57, and since reinforcing plate 57 prevents deformation of outer plate 51, there is no need to set the thickness of hot melt adhesive 59 to 0.1 mm or less.

[0032] The present invention is not limited to the above-described embodiment, and includes various modified examples. For example, in the above-described embodiment, the reinforcing plate 57 is used as an intervening member, but the intervening member may be a vacuum heat insulating material 56. That is, the vacuum heat insulating material 56 may be attached to the back surface of the outer plate 51. In this case, a hot melt adhesive 58 is applied between the back surface of the outer plate 51 and the vacuum heat insulating material 56 to bond them together. This makes it easier to automate the work than when adhesive tape is used for fixing them as in the past.

[0033] In addition, in this embodiment, the case where the outer plate 51 is formed of a steel plate has been described as an example, but the outer plate may be made of resin or glass. Even when the outer plate is made of resin or glass, by adhering a reinforcing plate as an intermediate member to the rear surface of the outer plate using a hot melt adhesive, it becomes easier to automate the work compared to the conventional attachment using an adhesive tape. [Explanation of symbols]

[0034] 1. Refrigerator 2a,2b,3a,4a,5a,6a Insulated Doors 51 Outer plate 55 Foam insulation 56 Vacuum insulation material 57 Reinforcement plate (intervening member) 57a Edge (edge ​​of intervening member) 58 Hot melt adhesive (adhesive that is in a liquid state when applied) T Thickness Y Space

Claims

1. The exterior plate and An intervening member provided on the back side of the outer plate; an adhesive that is in a fluid state when applied and bonds the outer panel and the interposed member; An insulated door with

2. The insulating door according to claim 1, A space facing the rear surface of the outer panel has a foam insulation material foamed in situ, the outer panel has a material that is deformable under the pressure of the foam insulation in place, The insulating door is characterized in that the adhesive is applied between the back surface of the outer panel and the intermediate member.

3. The insulating door according to claim 2, The insulating door is characterized in that the adhesive has a thickness of 0.1 mm or less in a solidified state.

4. The insulating door according to claim 1, A space facing the rear surface of the outer panel has a foam insulation material foamed in situ, the outer panel has a material that is deformable under the pressure of the foam insulation in place, An insulated door, characterized in that the adhesive is applied to the outer periphery of the interposed member between the back surface of the outer panel and the interposed member.

5. The insulating door according to claim 1, A space facing the rear surface of the outer panel has a foam insulation material foamed in situ, the outer panel has a material that is deformable under the pressure of the foam insulation in place, The insulating door is characterized in that the adhesive is applied to the entire outer periphery of the intervening member between the back surface of the outer panel and the intervening member.

6. The insulating door according to claim 5, The insulating door is characterized in that the adhesive is also applied to the center between the back surface of the outer panel and the intervening member.

7. The insulating door according to claim 5, An insulating door characterized in that the adhesive is applied up to the edge of the intervening member.

8. The insulating door according to claim 1, A vacuum insulation material is provided on the back surface of the interposition member, The insulating door is characterized in that the intervening member and the vacuum insulating material are bonded together using the adhesive.

9. A refrigerator comprising the insulating door according to any one of claims 1 to 8.

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