JPH06117749A - Heat insulating box body - Google Patents

Abstract

PURPOSE:To prevent secondary foaming of heat insulating material, which is caused when the box is used as a hot reserving chamber, by forming a heat resistant layer between an inner casing and the heat insulating material. CONSTITUTION:A metallic inner casing 2 is received in a metallic outer casing 3, opened upwardly, while the upper end rims of both of the casings 2, 3 are connected by a packing 14. A cooling pipe 6 is attached to and wound spirally around the outer surface of the side wall of the inner casing 2 while an electric heater 9 is attached to the lower surface of the bottom wall of the inner casing 2 through a heat transfer plate 8. A space between both of inner and outer casings 2, 3, excluding the bottom surface of the inner casing 2, and a bottom plate 7 is filled with foamed expandable polyurethane heat insulating material 11. A heat resistant layer 21, consisting of glass wool, is formed between the outer surface of side wall of the inner casing 2 and the heat insulating material 11. Accordingly, even when the temperature of the inner casing 2 is increased by the generation of heat of the heater 9, heat from the inner casing 2 is shielded by the heat resistant layer 21 and is hardly transferred to the heat insulating material 11 whereby the secondary foaming of the heat insulating material 11 is prevented and the generation of deformation of the heat insulating box itself can be prevented.

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 body in which a heat insulating material is foam-filled between an inner box and an outer box.

[0002]

2. Description of the Related Art Conventionally, this type of heat insulating box is disclosed in, for example,
As disclosed as a cooling box in Japanese Patent Publication No. 3-25251 (F25D15 / 00), it is configured by foaming and filling a urethane heat insulating material between an inner box and an outer box, and further, of urethane generated by temperature rise due to solar radiation. To prevent secondary foaming, a heat insulating sheet is provided outside the outer box. That is, when the heat insulating material is once foam-hardened and then reheated, secondary foaming is started, which causes the shape of the heat insulating material itself to be deformed, thereby deforming the entire heat insulating box.

By the way, in recent years, as shown in FIG.
A cold / hot refrigerator has been developed in which the storage chamber in the inner box can be switched and used in a cold or hot state. That is, to explain the structure of the conventional refrigerating cabinet 100 shown in FIG. 5, the metal inner box 2 that is open upward and has a metal inner box 2 that is also open upward at a certain interval. Stored, both boxes 2, 3
The upper edges of the are connected by a packing 4. Inner box 2
A cooling pipe 6 which constitutes a cooling device is spirally wound on the outer surface of the side wall of and is attached in a heat conductive relationship, and a bottom plate 7 is provided below the inner box 2. Further, an electric heater 9 composed of a sheathed heater as a heating device is attached to the lower surface of the bottom wall of the inner box 2 via a heat conduction plate 8 such as aluminum.

The inner and outer boxes 2, excluding the bottom wall of the inner box 2,
A heat insulating box body 101 having a storage chamber 12 opened upward in the inner box 2 is formed by foaming and filling a foamed polyurethane heat insulating material 11 by an in-situ foaming method between the bottom plate 7 and the bottom plate 7. Is closed by a heat insulating door 13. On the other hand, a machine room 14 is formed below the bottom plate 7, a compressor 16, a condenser 17 and a cooling fan 18 which constitute the cooling device are installed, and a central portion of the bottom plate 7 is opened and an electric heater 9 below the electric heater 9. The space communicates with the machine room 14. The compressor 16 and the condenser 17 together with the cooling pipe 6 constitute a known refrigeration cycle.

When the cold-storage cabinet 100 is used as a refrigerator with the above configuration, the electric heater 9 is de-energized and the compressor 16 is operated. The high-temperature and high-pressure refrigerant discharged from the compressor 16 is condensed by the condenser 17, decompressed by the decompressor (not shown), and flows into the cooling pipe 6. The refrigerant evaporates there and cools the wall surface of the inner box 2 by the endothermic action generated at that time, and cools the chilled food in the storage chamber 12 from the wall surface. When the cold storage 100 is used as a storage, the compressor 16 is stopped and the electric heater 9 is energized. As a result, the electric heater 9 generates heat and heats the inner box 2 via the heat conduction plate 8. The hot food in the storage chamber 12 is heated from the wall surface of the inner box 2 and kept warm.

[0006]

However, when the cold storage cabinet 100 is used as a storage cabinet, since the inner box 2 and the cooling pipe 6 are heated by the electric heater 9, the heat insulating material 11 in contact therewith is also heated. Will be done. As a result, the above-mentioned urethane secondary foaming occurs,
There is a problem that the heat insulating material 11 is deformed and the heat insulating box body 101 itself is deformed.

Further, in recent years, due to the problem of waste treatment that leads to environmental destruction, it is necessary to separate and separate both the metal inner and outer boxes 2 and 3 and the polyurethane heat insulating material 11 in the heat insulating box body. Although occurring, the polyurethane surface adheres to the surfaces of both the inner and outer boxes 2 and 3 during curing, so that there is a problem that the heat insulating box 101 cannot be separated smoothly when it is discarded.

The present invention has been made to solve the conventional problems, and an object thereof is to provide a heat-insulating box body which prevents secondary foaming of the heat-insulating material when it is used as a refrigerator. And Another object of the present invention is to provide a heat insulating box which facilitates the separation of the foamed polyurethane heat insulating material and the inner and outer boxes.

[0009]

A heat-insulating box body 20 according to a first aspect of the present invention comprises an inner box 2, an outer box 3, a heat-insulating material 11 foam-filled between the boxes 2 and 3, and an inner box 2. And a heating device (electric heater 9) for heating the inner box 2 and a heat-resistant layer 21 between the inner box 2 and the heat insulating material 11. Is formed.

The heat-insulating box body 20 according to a second aspect of the present invention is characterized in that the heat-resistant layer 21 is sealed with a non-hygroscopic material 22 at a portion exposed to the outside air. Further, the heat insulating box body 20 of the invention of claim 3 comprises an inner box 2, an outer box 3, and a foamed polyurethane heat insulating material 11 filled between both boxes 2, 3. The peeling layer 27 is formed between the inner box 2 and the outer box 3 and the heat insulating material 11.

[0011]

According to the heat-insulating box body 20 of the invention of claim 1, when it is used as a heating cabinet, a heating device (electric heater 9).
Even if the temperature of the inner box 2 rises due to the heat generation of, the heat from the inner box 2 is blocked by the heat-resistant layer 21 between the inner box 2 and the heat insulating material 11, and it becomes difficult to transfer to the heat insulating material 11. Secondary foaming can be prevented.

Further, in the above structure, when the heat insulating box 20 is repeatedly switched between cold storage and hot storage, the heat resistant layer 21 absorbs moisture in the outside air. According to this, since the heat-resistant layer 21 seals the portion exposed to the outside air with the non-hygroscopic material 22, it is possible to prevent the heat-resistant layer 21 from absorbing moisture in the outside air. Further, claim 3
According to the heat-insulating box body 20 of the invention described above, since the release layer 27 is formed between the inner box 2 and the outer box 3 and the foamed polyurethane heat insulating material 11, the foamed polyurethane adheres to the release layer 27 during curing, so The boxes 2 and 3 and the heat insulating material 11 can be easily separated.

[0013]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a vertical side view of a cold / hot warehouse 1 equipped with a heat insulating box 20 of the present invention, FIG. 2 is a perspective view of the cold / hot warehouse 1, and FIG. 3 is an electric circuit diagram of the cold / hot warehouse 1. In the figure, the same reference numerals as those in FIG. That is, in the case of the heat insulating box 20 of the present invention, the heat resistant layer 21 made of glass wool is formed between the outer surface of the side wall of the inner box 2 and the heat insulating material 11. The heat-resistant layer 21 is attached to the periphery of the inner box 2 from the outside of the cooling pipe 6 before the heat-insulating material 11 is foam-filled. Then, the foamed polyurethane heat insulating material 11 is foam-filled between the outer surface of the heat resistant layer 21 and the inner surface of the outer box 3. Also,
The lower end of the heat-resistant layer 21 is pulled out from the heat insulating material 11 into the outside air at the outer edge of the heat conducting plate 8, and the drawn out portion is coated with a non-hygroscopic material 22 such as silicon and sealed.

Further, in the electric circuit of FIG. 3, the compressor 16
The motors 16M and 18M of the blower 18 are connected in parallel, and the parallel circuit is connected in series to the refrigerating thermostat 23, and the refrigerating thermostat 23 is connected to the contact 25A of the cold / hot switch 25. Further, the electric heater 9 is connected in series with the heating thermostat 24, and the heating thermostat 24 is connected to the contact 25B of the cold / hot changeover switch 25. The cold / hot changeover switch 25 is attached to the side wall of the outer box 3.

The operation of the cold / warm refrigerator 1 will be described with the above configuration. When the cold storage 1 is used as a refrigerator, the changeover switch 25 is closed to the contact 25A. As a result, the electric heater 9 is de-energized, and the motors 16M and 18M are energized via the contacts of the refrigeration thermostat 23 to operate the compressor 16 and the blower 18. The high-temperature and high-pressure refrigerant discharged from the compressor 16 is condensed by the condenser 17 and decompressed by the decompressor (not shown) to be cooled by the cooling pipe 6.
Flow into. The refrigerant evaporates there and cools the wall surface of the inner box 2 by the endothermic action generated at that time, and cools the chilled food in the storage chamber 12 from the wall surface. The refrigeration thermostat 23 senses the temperature in the inner box 2 or the storage room 12,
For example, the contact is closed at + 7 ° C and the contact is opened at + 3 ° C. By this opening / closing operation, the compressor 16 and the blower 18 are controlled to be operated / stopped, and the refrigerated food in the storage chamber 12 is maintained at a refrigerated temperature of about + 5 ° C. on average.

When the cold storage 1 is used as a storage, the changeover switch 25 is closed to the contact 25B. As a result, the motors 16M and 18M are de-energized, and the electric heater 9 is energized via the contacts of the thermostat 24 for heating, and the electric heater 9 generates heat. The heat from the electric heater 9 is diffused by the heat conduction plate 8 and transferred to the inner box 2 to heat the hot food in the storage chamber 12 from the wall surface. The heating thermostat 24 senses the temperature in the inner box 2 or the storage chamber 12, and opens the contact at + 65 ° C. and closes the contact at + 61 ° C., for example. By this opening / closing operation, the electric heater 9 controls the heat generation, and the hot food in the storage chamber 12 is kept at an average temperature of about + 63 ° C.

When the cold storage 1 is used as a storage as described above, the temperature of the inner box 2 becomes a high temperature of + 60 ° C. or higher. When the polyurethane foam forming the heat insulating material 11 is exposed to such a temperature, there is a risk of secondary foaming. However, in the present invention, the heat insulating layer 21 and the inner box 2 are thermally insulated due to the presence of the heat resistant layer 21, and the heat between the two is increased. Since conduction is blocked, deformation of the heat insulating box 20 due to secondary foaming of the heat insulating material 11 is prevented.

Further, when the cold / hot refrigerator 1 is switched to refrigeration / hot storage as described above and repeatedly used, the temperature of the heat-resistant layer 21 made of glass wool also repeats high and low. Therefore, if the lower end of the heat resistant layer 21 is exposed to the outside air,
Moisture in the outside air is absorbed into the heat resistant layer 21 during refrigeration and condensed, so that the heat resistant layer 21 is flooded. When the heat-resistant layer 21 is flooded in this way, the heat-resistant effect decreases, and the heat-insulating material 11 is used during warming.
The effect of preventing the secondary foaming is reduced, and the heat insulating material 11 also absorbs water, which lowers the heat insulating performance. However, in the present invention, the heat resistant layer 21 is exposed to the outside air. Since it is sealed by the non-hygroscopic material 22,
The heat absorption effect of the heat resistant layer 21 does not occur, and the heat resistant effect of the heat resistant layer 21 and the heat insulating effect of the heat insulating material 11 can be favorably maintained.

Next, FIG. 4 shows a vertical side view of the cold storage box 1 equipped with another heat insulating box 20. Incidentally, FIG.
In FIG. 1, the same reference numerals as those in FIGS. 1 and 5 are the same. In this case, the heat insulating box body 20 is provided with a peeling layer 27 formed of a series of thin sheets made of polyethylene over substantially the entire inner surface of the inner box 2, the packing 4, the outer box 3 and the bottom plate 7. The release layer 27 is continuously arranged on the outside of the cooling pipe 6 on the outer surface of the side wall of the inner box 2, the lower surface of the packing 4, the inner surface of the outer box 3 and the upper surface of the bottom plate 7 before filling with the foamed polyurethane heat insulating material 11, and tapes the appropriate places. Etc. temporarily fix it. In this state, the heat insulating material 11 is foamed and filled. At this time, the heat insulating material 11 is adhered to the inner surface of the peeling layer 27 and hardened, and is not adhered to the inner box 2, packing 4, outer box 3 and bottom plate 7. Therefore, when the heat-insulating box body 20 is discarded, the inner box 2, the packing 4, the outer box 3 and the bottom plate 7 can be easily separated from the heat insulating material 11, and the separate disposal and collection can be performed very easily. Will be able to. Therefore, it becomes possible to prevent environmental destruction due to waste and to promote decomposition and reuse of various materials.

[0020]

As described above in detail, according to the invention of claim 1, even when the temperature of the inner box rises due to the heat generated by the heating device, the space between the inner box and the heat insulating material is used when used as a refrigerator. Since the heat-resistant layer of the heat shields the heat from the inner box and makes it difficult to transfer to the heat insulating material, it is possible to prevent secondary foaming of the heat insulating material and thereby prevent deformation of the heat insulating box itself. .

Further, according to the invention of claim 2, in the above structure, the portion of the heat resistant layer exposed to the outside air is sealed with a non-hygroscopic material, so that the heat resistant layer is prevented from absorbing moisture in the outside air. However, the heat resistance effect and the heat insulation effect of the heat resistant layer can be favorably maintained. Further, according to the invention of claim 3, since the peeling layer is formed between the inner and outer boxes and the foamed polyurethane heat insulating material, both the inner and outer boxes and the heat insulating material are easily separated when the heat insulating box body is discarded. Will be able to
The problem of environmental destruction caused by waste can be solved and the reuse of various materials can be promoted.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view of a cold storage box equipped with a heat insulating box of the present invention.

FIG. 2 is a perspective view of a cold storage cabinet.

FIG. 3 is an electric circuit diagram of a cold storage.

FIG. 4 is a vertical cross-sectional side view of a cold storage box equipped with another heat insulating box of the present invention.

FIG. 5 is a vertical cross-sectional side view of a cold storage cabinet equipped with a conventional heat insulating box.

[Explanation of symbols]

 1 Cold / Hot Storage 2 Inner Box 3 Outer Box 6 Cooling Pipe 9 Electric Heater 11 Heat Insulation Material 20 Insulation Box Body 21 Heat Resistant Layer 22 Non-Hygroscopic Material 27 Release Layer

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area B29K 105: 04

Claims (3)

[Claims] 1. A heat insulation comprising an inner box, an outer box, a heat insulating material foam-filled between both boxes, a cooling device for cooling the inner box, and a heating device for heating the inner box. A heat-insulating box body, wherein a heat-resistant layer is formed between the inner box and the heat insulating material. 2. The heat insulating box body according to claim 1, wherein a portion of the heat resistant layer exposed to the outside air is sealed with a non-hygroscopic material. 3. A heat insulating box body comprising an inner box, an outer box, and a foamed polyurethane heat insulating material filled between the two boxes, wherein a release layer is provided between the inner box and the outer box and the heat insulating material. A heat-insulating box body characterized by being formed.