JPH07146061A - Refrigerator - Google Patents

Abstract

PURPOSE:To provide a refrigerator in which leakage of heat insulator from an inlet when foaming agent having lower boiling point than the ordinary temperature is used can be suppressed. CONSTITUTION:The refrigerator comprises an inlet 13 formed on a back surface of an outer box 2, and a blocking member provided to open or close the inlet on a surface of the inlet at a heat insulator side, wherein a foamed heat insulated using foaming agent having lower boiling point than the ordinary temperature is filled from the inlet between an inner box and the outer box. Exhaust holes 15A, 15B of areas larger than that of the inlet are provided near the inlet 13 and/or at a bottom of the outer box.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator for suppressing the amount of heat insulating material leaking from an inlet formed on the back surface of the refrigerator.

[0002]

2. Description of the Related Art (I) Prior to the present invention, JP-A-60-36
Japanese Patent Laid-Open No. 868 discloses a method of manufacturing a heat-insulating box body in which a foaming gas exhaust hole is provided in a part of an outer box and the foaming gas is exhausted by forcibly depressurizing the exhaust gas through a decompression device. . In addition, (II) Japanese Patent Publication No. 53-6183 discloses an injection port formed by using a flexible blocking piece having one end fixed to a peripheral edge of the injection port formed in the container on the side filled with the heat insulating material. An infusion container adapted to be closed is disclosed.

[0003]

According to the manufacturing method (I), the foaming gas is forcibly discharged from the exhaust hole, so that forced gas convection occurs from the inlet to the exhaust hole. . Since the heat insulating material is also forcibly guided in the direction in which the foaming gas flows, the fluidity of the foam heat insulating material filled in the space formed between the inner and outer boxes is improved. However, since the decompression device has to be used, its manufacturing cost is increased and the price of the product is increased.

Further, when a foaming agent having a boiling point higher than room temperature such as R-11 (boiling point 23.8 ° C.) which is generally used as a foaming agent for foamed heat insulating material is used, the foaming rate of the heat insulating material is increased. Since the foaming is slow, the undiluted foam solution injected vigorously from the injection gun reaches the wall surface away from the injection port, foaming growth starts from this first reaching part, and the insulating material is slowly poured while filling the space between the inner and outer boxes. It grows in the direction of the inlet and pushes the blocking piece against the outer box. For this reason, the injection port can be well closed by the blocking piece of (II), and the leakage of the heat insulating material from the injection port can be prevented.

However, in recent years, from the viewpoint of protecting the ozone layer, the above-mentioned R-11 has been designated as a regulated refrigerant and its production and use have been restricted. R as an unregulated refrigerant
-141b (boiling point 31 ° C) and R-134a (boiling point-2)
6.5 ° C), R-22 (boiling point -40 ° C) and R-142b
(Boiling point-9 ° C) and the like are attracting attention. Since R-141b has a stronger influence on the inner box material than R-11, there is a problem that the inner box material has to be changed and the cost of parts is improved. In addition, R-22, R-142b and mixtures thereof (boiling point-
(29.4 ° C) and R-134a have boiling points lower than room temperature, (A) foaming undiluted solution is released from the injection gun into the atmosphere to immediately start foaming, and (B) the surface of the blocking piece and the inside and outside For the reason that the undiluted solution adhering to the inner surface (the surface on the heat insulating material side) of both boxes adheres to the peripheral portion of the inlet before closing the inlet with the flexible closing piece, the above (II (3) A gap is formed between the blocking piece and the peripheral portion of the injection port, and the injection port cannot be closed easily. Therefore, as a result, a large amount of foam insulation leaks out of the box through this gap, and the work to remove the insulation adhering to the foam jig increases, while the amount of insulation filling between the inner and outer boxes increases. However, there is a problem that the heat insulation performance of the heat insulation box is deteriorated due to the decrease in the number. 4 to 6 are attached as an outline of the structure and foaming growth state of the conventional heat insulating box. FIG. 4 is a perspective view of a box for explaining the injection of a heat insulating material of a conventional refrigerator, and FIG. 5 shows a case where a foaming agent having a boiling point lower than room temperature (for example, a mixture of R-22 and R-142b) is used. 4 is a sectional view taken along line IV-IV, and FIG. 6 is a foaming agent having a boiling point higher than room temperature (for example, R-1
FIG. 4 is a sectional view taken along the line IV-IV of FIG. 4 when 1) is used, and the reference numerals are the same as those in FIGS. 1 to 3.

Therefore, an object of the present invention is to provide a refrigerator capable of suppressing leakage of a heat insulating material from an injection port when a foaming agent having a boiling point lower than room temperature is used.

[0007]

SUMMARY OF THE INVENTION The present invention comprises an injection port formed on the back surface of an outer box, and a closing member provided on the surface of the injection port on the heat insulating material side so as to open and close the injection port. In a refrigerator in which a foam insulating material using a foaming agent having a boiling point lower than room temperature is filled between the inlet and the inner and outer boxes, the area of the inlet near the inlet of the outer box and / or the bottom of the outer box. It is intended to provide a refrigerator having an exhaust hole having a larger area.

According to the present invention, the inlets are formed at the left and right ends of the back surface of the outer box, the exhaust holes are formed in the bottom surface and the center of the back surface of the outer box, and the heat insulating material side of the peripheral portion of the inlet is provided. And a closing member provided to open and close the injection port on the surface of the refrigerator, and in which a foam insulation material using a foaming agent having a boiling point lower than room temperature is filled between the injection port and the inner and outer boxes, Provide holes for exhaust on the left and right ends on the back of the box,
(EN) A refrigerator provided with a sealing material for exhausting gas, which is made of a material that allows gas to pass therethrough and does not allow solids to pass therethrough, so as to close the hole.

Further, the present invention provides a refrigerator in which the area of the exhaust hole is larger than the area of the inlet.

[0010]

According to the first aspect, since the exhaust hole is formed in the vicinity of the inlet and / or in the bottom surface of the outer box, it is possible to form a gas flow path from the inlet and its vicinity to the exhaust hole. In particular, the area of the exhaust hole is larger than that of the inlet, and since there is no blocking member, the flow resistance is small. For this reason, when the foaming undiluted solution that uses a foaming agent with a boiling point lower than room temperature attached to the wall of the inner box located near the injection port foams and grows, it must flow through the wall of the inner box toward the exhaust hole. As a result, the backflow of the heat insulating material to the inlet side is suppressed, and as a result, the amount of the heat insulating material leaking from the inlet can be suppressed.

On the other hand, according to the second aspect, the foaming gas generated during the foaming growth of the injected foaming stock solution is not limited to the conventional flow path from the wall surface portion near the injection port where the foaming growth first starts to the exhaust hole. It is possible to form a new flow path from the wall surface portion in the vicinity of the injection port to the hole for exhaust, and it is possible to suppress the backflow of the heat insulating material to the injection port as compared with the conventional case.

On the other hand, according to the third aspect, the flow resistance of the new flow path toward the exhaust hole can be made smaller than the flow resistance of the gas flowing from the wall surface portion near the injection port toward the injection port.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 is a perspective view of a box for explaining the injection of the heat insulating material of the refrigerator of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, FIG. 3 is a sectional view taken along line III-III of FIG. 1, and FIG. Box perspective view for explaining the injection of the heat insulating material of the refrigerator of FIG. 5, FIG. 5 is a sectional view taken along the line IV-IV of FIG. 4 when a boiling agent having a boiling point lower than room temperature is used, and FIG. FIG. 4 is a sectional view taken along line IV-IV of FIG.

In FIG. 1, reference numeral 1 is a refrigerator. This refrigerator is composed of an outer box 2 made of a metal whose surface is coated, an inner box 3 made of a synthetic resin such as ABS, and a foam heat insulating material 4 filled in a space K formed between the inner and outer boxes. The heat insulating box body 5 and a door body (not shown) that opens and closes the opening of the heat insulating box body 5 are configured. In addition, in the heat insulation box 5,
A partition member 6 is attached to partition the interior of the refrigerator into a freezer compartment and a refrigerator compartment. The foamed heat insulating material is a rigid polyurethane foam obtained by reacting a polyether polyol and a polyisocyanate in the presence of a foaming agent, and as the foaming agent, monochlorodifluoromethane (R-22) and 1,1 are used.
-A mixture of dichloro-1-fluoroethane (R-142b) and at least 35% by weight of R-22 is used in an amount of 5 to 55 parts by weight per 100 parts by weight of polyol.

The polyether polyol is an aliphatic type and has an average number of functional groups of 2 to 4, 20 to 70 parts by weight, an average number of functional groups of 3 to 5 is 15 to 60 parts by weight, and an aromatic amine type is an average number of functional groups. It is a mixture of 3 to 5 and 65 parts by weight or less, and a hydroxyl value of 350 to 500 mg KOH / which is obtained by adding alkylene oxide to this initiator mixture.
g of polyol is used. Specifically, sucrose and
It is a polyol having a hydroxyl value of 450 mgKOH / g obtained by adding propylene oxide to a mixed solution of an initiator in which pentaerythritol, toluenediamine, and glycerin are mixed in a ratio of 4: 2: 2: 2.

As the polyisocyanate, all known organic polyisocyanates can be used, but the most common ones are toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI). TDI is a mixture of isomers, ie 2,4-body 100
% Product, 2,4-body / 2,6-body = 80 / 20,65 / 3
5 (each polymerization ratio) and so on, and so-called crude TDI containing a polyfunctional tar known as Mitsui Cosmonate TRC under the trade name, Takenate 4040 by Takeda Yakuhin, etc. can be used. Further, as the MDI, in addition to a pure product containing 4,4′-diphenylmethane diisocyanate as a main component,
Polymec MDIs such as Mitsui Cosmonate M-200, which is a trade name containing polyhedra with three or more nuclear bodies, and Millionate MR manufactured by Takeda Pharmaceutical Co., Ltd. can be used. The organic polyisocyanate and NCO / H (active hydrogen) of the active hydrogen in the resin solution described later
= 0.70 to 5.00 (equivalent ratio) is particularly suitable, and specifically, the above-mentioned Cosmonate M-200 (manufactured by Mitsui Toatsu Chemicals, Inc.) or Polymec MDI (NCO31.
3%).

The monochlorodifluoromethane (R-2
2) has a boiling point of -41 ° C and a steam thermal conductivity of 0.0091 Kc.
Vapor pressure at al / mhr ° C, + 21 ° C 9.5Kg / cm
2. Having characteristics of non-combustible gas, 1-chloro-1,1-difluoroethane (R-142b) has a boiling point of -9 ° C, a vapor thermal conductivity of 0.0095 Kcal / mhr ° C, and a vapor pressure of + 21 ° C. It has a characteristic of flammable gas of 1 kg / cm2. As the foaming agent, monochlorodifluoromethane (R-22) is mixed in an amount of 35% by weight or more to keep 1-chloro-1,1-difluoroethane (R-142b) in a non-flammable range. Is R-22 and R-14
2b were mixed in a ratio of 4: 6 (R-22 and R-142b
When mixed at a ratio of 4: 6, the boiling point is −29.4 ° C.
5) to 55 parts by weight per 100 parts by weight of polyol.

Then, the above-mentioned polyether polyol and reaction catalyst (tetramethylhexamethylenediamine, etc.)
A foam stabilizer (organic silicon surfactant), water and the above-mentioned foaming agent are made in a predetermined amount in a closed container, and transferred to a high-pressure foaming machine in a closed state to obtain a resin. The liquid of this resin and the above organic polyisocyanate (Cosmonate M-200) was adjusted to + 20 ° C., the discharge rate of the high-pressure foaming machine was set to 30 Kg / min, and the undiluted solution of the resin and the organic polyisocyanate (foaming liquid) was added at the ratio described below. Is injected into the space between the outer box 2 and the inner box 7 as indicated by the arrow in FIG. The above blending ratio is based on the assumption that the polyether polyol is 100, the polyisocyanate is 125, the catalyst is 4.0, the foam stabilizer is 1.5, water is 0.4, R-22 is 12, R- 142b is 18 parts by weight.

The inner box 3 is integrally formed with a top surface, left and right side surfaces, a back surface and a bottom surface, and a series of grooves (not shown) for inserting and fixing the partition member 6 is formed on the left and right side surfaces and the back surface. I am doing it. Further, in order to make the heat insulation performance of the heat insulation box body different between the freezer compartment and the refrigerating compartment, the distance between the upper box and the outer box from the groove of the inner box is different from the lower section and the outer box from the groove of the inner box. The inner box is intentionally formed in a stepped shape with this groove as a boundary so as to be larger than the gap. A recess 7 is formed at the intersection of the inner wall surface of the inner box and facing the injection port 13 of the outer box, which will be described later, to secure a distance from the injection gun inserted from the injection port.

The outer box 2 includes left and right side surfaces 2b and 2c and a top surface 2.
a main body 2A in the form of a gate, a back plate 2D attached to the main body 2A to form a back surface 2d, and the main body 2
A and a bottom plate 2E attached to the back plate 2D and forming a bottom face 2e of the outer box. A plurality of (five in the embodiment) exhaust holes 11 are formed at intervals in the up-down direction in the center portion of the back plate 2D of the outer box in the left-right direction, and the same exhaust holes 11 are formed in the bottom plate 2E of the outer box. Is formed.

Injection ports 13 for inserting the injection gun 12 of the heat insulating material are respectively formed at appropriate positions on the left and right ends of the back plate 2D of the outer box, and the peripheral portion of the injection port is formed on the heat insulating material side surface of the back plate 2D. A closing member 14 made of a flexible and inexpensive material such as a paper material such as cardboard or corrugated cardboard or a resin material such as polypropylene is attached thereto. When the injection gun 12 is inserted into the injection port 13, the blocking member 14 is pushed toward the inner box 3 side by the injection gun 12 and bends. This is for closing the inlet 13 so that the heat insulating material 4 does not leak from the inlet 13. In the embodiment, only one end of the closing member 14 is bonded.

15A is an exhaust hole (hereinafter referred to as an exhaust hole) formed in the vicinity of the inlet 13 of the outer case back plate 2D (four in the embodiment), and 15B is a long distance from the inlet. Outer box bottom plate 2E that tends to be the final filling part of the heat insulating material
There are a plurality of (6 in the embodiment) exhaust holes. By appropriately setting the number and diameter of the exhaust holes 15A and 15B, the total area thereof may be equal to or larger than the total area of the inlet 13. Incidentally, in the example, the diameter of the inlet 13 was set to 40 mm and the diameter of the exhaust hole was set to 20 mm.

As shown in FIG. 2, a gas formed of a material such as a non-woven fabric that does not allow solids to pass therethrough on the inner box side surface of the outer box 2 and at the peripheral edge of the exhaust holes 15A and 15B. A sealing material 16 for exhaust is attached.

Next, a method of manufacturing the heat insulating box, such as a procedure for injecting the heat insulating material 4 into the heat insulating box 5, will be described. First, the inner box 3 is inserted into the outer box 2 from the opening on the front side with a predetermined space between the left and right sides of the nadir and the back side. As shown in FIG. 1, the outer box 2 and the inner box 3 assembled in this way are set in a foaming mold (not shown) with their openings on the lower side. The foaming mold presses the inner box 3 from the inner side and the outer box 2 from the outer side to face the foaming pressure. Then, in this state, the injection gun 12 is inserted into the injection ports 13 and 13 to inject a stock solution of the heat insulating material (a foaming stock solution).

Here, since the foaming agent of the mixture of R-22 and R-142b is no longer liquid at room temperature (+ 20 ° C.), as described above, between the injection gun (high pressure foaming machine) and the outer box 2 and the inner box 3. Immediately after being discharged into the space K, the undiluted solution becomes floss (foam) and starts expanding. Therefore, the inlet 1
The undiluted solution that entered the space K from 3 and 13 grows along the wall surface. At this time, if the injection gun 12 is removed, the closing member 14 acts so as to close the injection port 13 by its restoring force, and the flow resistance of the gas and the heat insulating material at the injection port 13 portion increases. On the other hand, the exhaust holes 15A and 15B are designed so that the passage of solids is blocked by the sealing material 16, but gas can pass therethrough, so the flow path resistance to gas is smaller than that of the inlet 13. Moreover, since the area of the exhaust hole is larger than the area of the inlet, the flow path resistance of the gas is smaller. Therefore, the undiluted solution (foaming undiluted solution) of the growing heat insulating material is discharged from the wall surface of the inner box near the inlet 13 to the exhaust hole 15 near the inlet.
It becomes easier to flow toward A. Therefore, the leakage amount of the heat insulating material from the inlet 13 can be suppressed.

That is, since the exhaust holes 15A and 15B are formed in the vicinity of the injection port 13 and in the bottom surface of the outer box, a gas flow path from the injection port and the vicinity thereof to the exhaust hole can be formed. Has a larger area than the inlet and does not have a blocking member, so the flow resistance is small. For this reason, when the foaming undiluted solution that uses a foaming agent with a boiling point lower than room temperature attached to the wall of the inner box located near the injection port foams and grows, it must flow through the wall of the inner box toward the exhaust hole. As a result, the backflow of the heat insulating material to the inlet side is suppressed, and as a result, the amount of the heat insulating material leaking from the inlet can be suppressed. Further, the foaming gas generated at the time of foaming growth of the injected foaming undiluted liquid is generated from the wall surface part near the injection port in addition to the conventional flow path from the wall surface part near the injection port where the foam growth first starts to the exhaust hole 11. A new flow path toward the exhaust hole 15A can be formed, the backflow of the heat insulating material to the inlet can be suppressed more than before, and the flow resistance of the gas flowing from the wall surface portion near the inlet toward the inlet 13 can be further suppressed. The flow resistance of the new flow path toward the exhaust hole 15A can be made smaller than that.

Then, the polyether polyol and polyisocyanate react with each other, and the heat of the reaction further gasifies the foaming agent to confine it in the foam, so that the undiluted solution expands (the surface begins to solidify) from the side wall of the inner box 3. It fills in the direction of the top wall and back wall, and finally enters from the left and right sides of the bottom wall to be solidified, and a hard polyurethane foam (heat insulating material) is molded between the boxes 2 and 3. Then, 7 minutes after the injection, the heat-insulating box body 5 is obtained by demolding.

In particular, in the examples, the above-mentioned R-2 was used as a foaming agent.
Since the mixture of 2 and R-142b is used, it is possible to contribute to environmental protection without using regulated CFCs. still,
In the examples, the mixture of R-22 and R-142b was used as the foaming agent, but it is not limited thereto, and R-22 or R-14 may be used.
2b may be used alone, or R-134a may be used as a foaming agent.

[0029]

As described above, according to the first aspect of the present invention, since the exhaust hole is formed in the vicinity of the inlet and / or in the bottom surface of the outer box, the gas directed from the inlet and its vicinity to the exhaust hole is formed. A flow path can be formed, and in particular, the area of the exhaust hole is larger than that of the inlet, and since there is no blocking member, the flow resistance is small. For this reason, when the foaming undiluted solution that uses a foaming agent with a boiling point lower than room temperature attached to the wall of the inner box located near the injection port foams and grows, it must flow through the wall of the inner box toward the exhaust hole. As a result, the backflow of the heat insulating material to the inlet side is suppressed, and as a result, the amount of the heat insulating material leaking from the inlet can be suppressed.

On the other hand, according to the second aspect, the foaming gas generated during the foaming growth of the injected foaming stock solution is not limited to the conventional flow path from the wall surface portion in the vicinity of the injection port where the foaming growth first starts to the exhaust hole. A new flow path can be formed from the wall surface near the inlet to the exhaust hole, and a sealing material that allows gas to pass through is provided in the exhaust hole, so the flow resistance of gas is smaller than that of the inlet. It is possible to suppress the backflow of the heat insulating material to the inlet as compared with the conventional case.

On the other hand, according to claim 3, the flow resistance of the new flow path toward the exhaust hole can be made smaller than the flow resistance of the gas flowing from the wall surface portion near the injection port toward the injection port.

[Brief description of drawings]

FIG. 1 is a perspective view of a box for explaining injection of a heat insulating material of a refrigerator according to the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a perspective view of a box for explaining injection of a heat insulating material of a conventional refrigerator.

5 is a cross-sectional view taken along line IV-IV of FIG. 4 when a foaming agent having a boiling point lower than room temperature is used.

6 is a sectional view taken along line IV-IV in FIG. 4 when a foaming agent having a boiling point higher than room temperature is used.

[Explanation of symbols]

 1 Refrigerator 2 Outer Box 2D Back Plate 2E Bottom Plate 3 Inner Box 4 Foam Insulation Material 5 Insulation Box Body 11 Exhaust Hole 13 Inlet Port 14 Closing Member 15A, 15B Exhaust Hole (Exhaust Hole) 16 Sealing Material

Claims (3)

[Claims] 1. An inner and outer box from the inlet, comprising an inlet formed on a back surface of the outer box and a closing member provided on a surface of the inlet facing the heat insulating material so as to open and close the inlet. In a refrigerator filled with a foamed heat insulating material using a foaming agent having a boiling point lower than room temperature, an exhaust hole having an area larger than the area of the inlet is provided near the inlet of the outer box and / or on the bottom of the outer box. A refrigerator characterized by being provided. 2. An inlet formed at both left and right ends of a back surface of the outer box, an exhaust hole formed at a bottom surface and a central portion of the back surface of the outer box, and a heat insulating material side surface of a peripheral portion of the inlet. In a refrigerator having a closing member provided to open and close the inlet, and filling a foamed heat insulating material using a foaming agent having a boiling point lower than room temperature from the inlet to the inner and outer boxes, the rear surface of the outer box. A refrigerator for exhausting gas is provided at both left and right ends, and a sealing material for exhausting gas, which is made of a material that allows gas to permeate and does not allow solids to permeate, is provided so as to close the hole. 3. The refrigerator according to claim 2, wherein the area of the exhaust hole is larger than the area of the inlet.