JPH05157446A - Casing of refrigerator - Google Patents

Abstract

PURPOSE:To bury completely in rigid polyurethane foam a container for vacuum heat-insulation material which container, when placed in contact with a gas, is easily permeable to the gas because of the use of a plastic film and a laminated film of metal foils as the components. CONSTITUTION:To form an insulating casing of refrigerator, a unitized outer casing-member of refrigerator comprising a vacuum heat-insulation material 2, an outer plate of refrigerator, and rigid polyurethane foam is formed, which, together with an inner casing 3, is formed into a casing and, by being filled with rigid polyurethane foam 4 again, the casing is formed into an insulating casing of refrigerator. This constitution can prevent deterioration of a vacuum heat-insulation material which is possible when a plastic laminated film is used for the container.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating box for a refrigerator, and more particularly to a heat insulating box having a panel in which a vacuum heat insulating panel and a rigid urethane foam are combined.

[0002]

2. Description of the Related Art Conventionally, a rigid urethane foam has been used as a heat insulating material for a refrigerator, or a combination of urethane foam and a vacuum heat insulating material has been used for the purpose of a higher performance heat insulating material. Trichloromonofluoromethane (R-11) is used as a foam material for rigid urethane foam, but R-11 is one of the persistent CFCs (abbreviation of Chloro, Fluoro, Carbon) and is commonly called Freon. . When this CFC is released into the atmosphere, it is said that the ozone layer will be destroyed in the stratosphere and the surface temperature will rise due to the greenhouse effect, which has become a global environmental pollution problem. Therefore, a method of using a rigid urethane foam without R-11 as a heat insulating material has been invented. R
-11 substitutes include, for example, HCFC (Hydoro, Cheoro,
R-123, R-141b (abbreviation of Fluoro, Carbon), carbon dioxide gas, or the like, or a combination thereof may be considered, but all of them have inferior heat insulation performance as compared with the case of using R-11. For this reason, a high-performance vacuum heat insulating material and a rigid urethane foam using an alternative foaming agent of R-11 are often combined to form a heat insulating box.
A laminated film of plastic / metal foil is often used as a container material for mass production or cost reduction of the vacuum heat insulating material. Gas easily permeates the inside of the container through the laminated film or the welded portion of the film, and the degree of vacuum inside gradually deteriorates, making it difficult to guarantee the product for many years in actual use. However, the conventional vacuum heat insulation panel is attached to the plate of the outer box in the space formed by the inner box and the outer box of the refrigerator by using an adhesive or the like, and filling the still empty part with hard urethane to form the box. I was there. In this method, that is, when the vacuum heat insulating material is attached to the iron plate of the outer box with an adhesive or the like, the vacuum heat insulating material has small irregularities and cannot be flattened, so a small gap is inevitably formed between the vacuum heat insulating material and the iron plate. . Therefore, there is a drawback that the gas in the gap penetrates through the container material of the vacuum heat insulating material or the welded portion of the container material to lower the degree of vacuum inside. Note that examples of this type of vacuum heat insulating material include, for example, Japanese Examined Patent Publication No. 63-204088,
There is Japanese Examined Japanese Patent Publication No. 63-204089.

[0003]

As a container material for a vacuum heat insulating material, a plastic film or a laminated film of a plastic / metal foil is used because the cost is low and the material cost is low and the container manufacturing and sealing work is easy. Moreover, when a metal foil is used, the foil as thin as possible is used in order to reduce heat conduction from the metal foil itself. Therefore, gas and especially water vapor easily permeate through the laminate film itself and the welded portion for forming the container, which deteriorates the vacuum degree of the vacuum heat insulating material. Therefore, in order to completely maintain the degree of vacuum, the air layer is completely removed from the outer periphery of the vacuum heat insulating material to achieve the desired long-term retention of the degree of vacuum of the vacuum heat insulating material.

[0004]

In order to achieve the above object, a method of completely filling a vacuum heat insulating material with a rigid urethane foam used as a heat insulating wall of a refrigerator. However, if you set the vacuum heat insulating material in the space that can be simply combined with the inner box and the outer box and inject the undiluted solution of hard urethane to foam,
The foam material foams from the pouring site and fills as a flow, but at this time the vacuum heat insulating material becomes a flow resistance, it is biased by the flow pressure, or it completely obstructs the flow and completely It was difficult to bury it inside.
Therefore, in the present invention, the outer panel of the refrigerator is formed into a panel, and as the configuration of the panel, a hard urethane foam is injected onto an iron plate, a vacuum heat insulating material is placed on the panel, and foamed in the mold to form an iron plate / hard urethane foam / vacuum. It is a refrigerator box body in which a panel formed by combining heat insulating materials is combined to form an outer box, and a space formed by combining the inner box is filled with hard urethane foam again.

[0005]

In order for the vacuum heat insulating material to maintain the initial degree of vacuum, first, in order to completely remove air from between the outer wall of the refrigerator and the vacuum heat insulating material, the vacuum heat insulating material is divided into blocks as shown in FIG. A hard urethane foam 6 is filled between the material 2 and the material 2.
The rigid urethane foam 6 functions to remove air and bond the vacuum heat insulating material to the outer plate. Further, the rigid urethane foam 4 in FIG. 1 is filled with a gap formed by each block outer box member (item shown in FIG. 4) and the inner box 3 to bond and fix the outer box member and the inner box, and further the urethane foam. It acts as a heat insulator due to its own heat insulating property.

With the above construction, the vacuum heat insulating material acts as a high performance heat insulating material, and R-11 is not used as the foam material of the rigid urethane foam used, and a substitute (for example, R-
123, R-141b, carbon dioxide gas), the heat insulating performance can be improved without being deteriorated.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a plan view of a cross section of a heat insulating box for a refrigerator. FIG. 2 shows a state in which the outer plate material 6 is set on the foaming subordinate 7 for manufacturing the outer box member shown in FIG. 4 and the source liquid 9 for hard urethane foam is injected from the injection head 10 for the foaming machine. It is what FIG. 3 is a cross-sectional view showing a state in which the foaming has been completed by injecting the rigid urethane foam in FIG. FIG. 4 is a cross-sectional view of what has been foamed in FIG. 3 and completed as a refrigerator outer box member.
Reference numeral 1 represents a refrigerator box. 2 is a vacuum heat insulating material, and the container material is polyethylene 50 μm / aluminum vapor deposition foil 0.0
A glass wool mat having a thickness of 50 mm was used as a core material which was heat-sealed around the entire periphery thereof using a laminated film of 5 μm / polyethylene terephthalate 50 μm. Reference numeral 3 is an inner box for a refrigerator, which is a vacuum-molded product of ABS resin. Reference numerals 4 and 5 are rigid urethane foams, and water is used as a foaming material. The water reacts with isocyanate, which is the main component of urethane, to generate carbon dioxide gas, and the foaming gas becomes carbon dioxide gas. Reference numeral 6 was an outer plate, the outer side of which was previously painted.
Reference numerals 7 and 8 denote foaming work for blocking the outer case outer plate 6 and the vacuum heat insulating material 2 with the hard urethane foam 5.
Actually, the upper 8 and the lower 7 need a clamp mechanism (not shown) because they are pushed up and down by the foaming pressure when foaming. Reference numeral 10 denotes an injection nozzle of a hard urethane foaming machine (not shown) injection head. The above-mentioned outer box member shown in FIG. 4, that is, the hard urethane foam of combination 4 as shown in FIG. 1 is set in a refrigerator box foaming employment (not shown) and foamed by a foaming machine similar to the foaming machine shown in FIG. The first box for refrigerator is completed.

In this embodiment, as shown in FIG. 3, when the rigid urethane foam 5 is foamed, the vacuum heat insulating material 2 is set to 8 for foaming and the vacuum heat insulating material 2 is attached to the outer box member at the same time. However, it is also possible to incorporate the shape of the vacuum heat insulating material 2 into the foam upper layer 8 in the state of FIG. 3 to form a space and attach the vacuum heat insulating material 2 after foaming to obtain the shape of FIG.

Alternatively, the outer plate 6 shown in FIG. 3 is not set, only foaming is performed, and then the outer plate 6 and the vacuum heat insulating material 2 are incorporated later to obtain the state of FIG. 4, and only the outer plate 6 is not set. It is also possible to set the vacuum heat insulating material 2 in advance and then set the outer plate 6, and the same effect as that described above can be obtained.

Further, FIG. 5 shows a transition of the amount of heat leakage of the refrigerator box according to the present invention and a comparison with a conventional product. The condition is a refrigerator box of 360 liters, the upper part is a freezing room 74 l · -18 ° C, the lower part is a refrigerating room 286 l · -7 ° C, and the amount of heat leakage at an outside air temperature of 30 ° C is measured. A total of 6 pieces are installed on the entire freezer compartment and the back of the refrigerator compartment. As an accelerating test, the sample was left at 60 ° C. and the amount of heat leakage was measured every month under the above conditions. The result shows that the heat leakage amount 11 of the present invention hardly changes and the heat insulating performance is maintained, while the heat leakage amount 12 of the conventional product significantly increases the heat leakage amount and deteriorates the heat insulating performance. You can see that

In this embodiment, the non-Freon foam is used, which is a combination of urethane foam made by water foaming and a vacuum heat insulating panel. However, HCFC123 or HCFC141b is used.
The same effect is obtained even when is used as the foaming agent.

[0013]

According to the present invention, even in the case of a vacuum heat insulating material container made of plastic and metal foil, the circumference of the vacuum heat insulating material is completely covered with the rigid urethane foam, so that gas permeation from the vacuum heat insulating material container and total It is possible to remarkably reduce gas permeation from the heat-welded portion of the surrounding plastic laminate film portion, and to remarkably improve the heat insulating performance maintaining effect of the refrigerator heat insulating box using the vacuum heat insulating material.

[Brief description of drawings]

FIG. 1 is a plan view of a cross section of a heat insulating box for a refrigerator according to the present invention.

FIG. 2 is a cross-sectional view of a foaming source liquid injection state of a block for an outer box of the present invention.

FIG. 3 is a cross-sectional view of a set for foaming to manufacture a block for an outer box.

FIG. 4 is a cross-sectional view of the completed state of the block product for the outer box.

FIG. 5 is a diagram showing changes in the amount of heat leakage of the refrigerator box.

[Explanation of symbols]

 1 ... Insulation box for refrigerator 2 ... Vacuum insulation material 3 ... Refrigerator inner box 4 ... Hard urethane foam 6 ... Outer box iron plate 7 ... Outer box block hiring 8 ... Outer box block hiring 10 ... Hard Injection nozzle for urethane foaming machine 11 ... Transition of heat leakage amount of the present invention 12 ... Transition of conventional heat leakage amount

Claims (1)

[Claims] 1. A refrigerator thermal insulation box body, in which hard urethane foam is previously installed inside an iron plate which is an outer surface, and a vacuum heat insulating material is further installed inside thereof to form a panel shape, which is combined to form an outer box, A box body for a refrigerator characterized in that a hard urethane foam is further injected into a space portion formed by combining this and an inner box formed by plastic molding to form a heat insulating box body.