KR20050028296A - Refrigerator - Google Patents

Abstract

A refrigerator is provided to improve insulation efficiency by effectively mounting vacuum insulating panels in an insulating space of a cabinet, while keeping the strength of the cabinet and the filling performance of urethane foam. A refrigerator includes vacuum insulating panels(1) adhered to an inner surface of an insulating space of a cabinet, wherein the panels are adhered by a coating rate in the range of 20%-50% with respect to an outer surface area of the cabinet, thereby forming improving insulating efficiency together with foaming insulating materials filled in the cabinet.

Description

Refrigerator {REFRIGERATOR}

The present invention relates to a refrigerator in which a vacuum insulation panel is adhered to an insulation space of a cabinet to form an insulation layer together with a foam insulation.

Conventionally, as a heat insulator of a heat insulation cabinet in a refrigerator, a polyurethane foam having low thermal conductivity and having rigidity integrated with an outer box or an inner box constituting the cabinet by foam filling has been mainly used. In order to further reduce the amount of power consumed by preventing heat leakage and to reduce the thickness of the heat insulating wall or to improve the volumetric efficiency of the refrigerator, a vacuum insulating panel as a heat insulating material has been put to practical use in part.

The vacuum insulated panel 51 shown in FIG. 6 as a basic example of the use as a refrigerator is designed to suppress material costs, to function at relatively high internal pressures to facilitate long-term reliability by suppressing exhaust and vacuum levels. The core material 51a is formed of a laminated film of synthetic resin and aluminum foil, using resin foam, an inorganic fine powder, and fibers having a communication bubble structure that can form a space and maintain its shape under atmospheric pressure. After covering with a gas-barrier container 51b, making the inside of the container 51b into a vacuum state, the opening was sealed by heat-sealing 51c.

In addition, in order to maintain the degree of vacuum by suppressing the deterioration due to the passage of time due to the increase in pressure due to the gas generated from the core material 51a and the gas penetrating into the interior through the seal surface or surface of the airtight container 51b. A getter made of a metal such as titanium, magnesium, an alloy such as barium / lithium, an oxide such as cobalt oxide, calcium oxide, zeolite, activated carbon, or the like, which adsorbs air components such as moisture, oxygen, nitrogen, or gas such as hydrogen ( It is common to enclose 56).

In terms of thermal insulation performance, inorganic fine powder such as ferrite is used as the core material, since the wall thickness of the fine powder solid itself is large and the space volume for thermal insulation is low, and as shown in FIG. Since the core material has a strength limit in the size of the bubble cell, the thermal conductivity of the vacuum insulation panel is limited to about 0.005 to 0.007 W / mK. The material which can obtain the heat conductivity below that is glass wool of several micrometers or less in fiber diameter, and when it is made into a core material, many small spaces can be formed, and it has a low heat conductivity of about 0.002 W / mK. It can be realized.

The vacuum insulation panel is installed on the inner surface of the refrigerator or door by 50% or more by fixing the tape or adhesive fixing by double-sided tape or hot melt and at the same time maintaining the strength of the box by using it together with rigid urethane foam. There is a thing which has insulation performance (for example, Unexamined-Japanese-Patent No. 2003-28562).

However, if the covering ratio of the vacuum insulation panel to the surface area of the outer box is 50% or more, in consideration of the installable area for the entire inner area, the vacuum insulation panel is practically applied to almost all surfaces such as the upper surface, the rear surface, or the surface of each door. It is necessary to install it, and depending on the installation part, a special panel shape may be required or it may become an unreasonable attachment structure.

Since the circumference of the vacuum insulated panel is covered with the air insulating container 51b made of a laminated film of synthetic resin and aluminum foil as described above, the heat of the outer box is the heat insulating wall through the circumference of the air insulating container 51b. Is conducted in the thickness direction, and as a result, the heat insulating effect of the portion is significantly lower than that of the panel center portion. That is, since the average thermal conductivity of the panel as a whole becomes larger as the area of the panel 51 becomes smaller, the installation on a large number of wall surfaces including a small door surface lowers the efficiency of use as a vacuum insulation panel, and the cost increase due to a large number of uses. It is accompanied by a decrease in cost effectiveness.

In addition, the installation of a large number of sheets on each wall surface also causes a problem that the filling efficiency decreases, such as a large volume of the vacuum insulation panel occupying the heat insulating space, a flow of the injected urethane foam is inhibited, and a large number of unfilled portions and voids are caused. As the area occupied in the cabinet of the vacuum insulation panel increases, the adhesion area between the foam insulation and the inner surface of the cabinet decreases, and there is a concern that the overall rigidity of the insulation cabinet decreases as compared with the conventional one, depending on the installation position and the shape of the panel.

In addition, when the vacuum insulation panel is used to avoid the uneven portion due to the parts installed in the heat insulating space, the vacuum insulation panel is divided in-plane. However, as described above, the smaller the surface area of the vacuum insulation panel, the larger the average thermal conductivity of the entire panel. In the same manner as in the case of employing a door having a defect in which the use efficiency is lowered and having a small surface area, the original thermal insulation effect is lowered.

The present invention has been made in consideration of the above points, and by the effective installation of the vacuum insulation panel in the insulation space of the cabinet, the cost increase can be suppressed to improve the insulation efficiency, and the stiffness of the cabinet is not reduced. An object of the present invention is to provide a refrigerator in which strength is maintained well.

In order to solve the above problems, the refrigerator of the present invention is a glass wool mat as a core material in the airtight container to be stored in a vacuum container to evacuate the inside of the vacuum insulation panel made of a panel body to the inner surface of the heat insulating space of the refrigerator cabinet, urethane in the remaining space In foam filling of a foam and embedding it, the vacuum insulation panel is bonded with a coverage of 20% or more and less than 50% with respect to the outer surface area of the refrigerator cabinet.

By this structure, the heat insulation effect of the cabinet using a vacuum insulation panel can be exhibited, and while reducing the heat insulation performance of the use of a vacuum insulation panel by installing several sheets, it is possible to reduce cost and to improve cost-effectiveness. In addition, the filling efficiency of the urethane foam can be improved and the rigidity of the cabinet can be increased.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described based on drawing. As shown in Fig. 1 and Fig. 2 showing the vacuum forming state of the panel, the vacuum insulation panel 1 is made of glass wool, which is a cotton-like material of fine glass fibers having an average fiber diameter of 4 m, as the core material 1a, At the same time, the core material 1a was formed into a bag-shaped air-tight container 1b having a thickness of 80 to 100 µm, in which a laminated film of aluminum foil and synthetic resin was formed into a bag shape. After insertion, the container 1b is placed on a two-stage stage 3b installed in the vacuum chamber 3 disposed on the base 3a of the vacuum forming apparatus 2, and is 0.03 by the vacuum pump 3c. After evacuating to about 30 Pa, the opening of the container is closed with a margin of 20 to 50 mm, and heat-bonded 1 c over the 10 mm width of the margin, thereby keeping the inside of the container 1 b in a vacuum depressed state. It is formed into a shape.

Thereafter, the core member 1a is further compressed to about one-half by the pressure difference caused by opening the inside of the chamber 3 to atmospheric pressure, and finally the thickness of 12 mm and the size of the length and width are 1400 mm and 500, respectively. The vacuum insulation panel 1 of which mm is formed is formed, and the vacuum insulation panel 1 rotates the chamber coat 3e in the direction of the upward arrow with the hinge portion 3d as a support shaft, and moves up and down in the same manner. It is discharged by sliding from the open opening of the heat bonding bar 3f.

The vacuum insulated panel 1 formed by the above can have a thermal conductivity of 0.003 W / mK or less at the center of the panel surface, and the discharged vacuum insulated panel 1 is formed of a rubber-based material over almost the entire surface of one side surface. The hot melt adhesive 4, which is a thermoplastic resin, is uniformly applied, and as shown in FIG. 3, the hot melt adhesive 4 is supplied to the upper portion of the outer box 6 in a flat state moving on the assembly line conveyor of the refrigerator to supply the hot melt adhesive 4 By the adhesive force of), it adhere | attaches to the heat insulation space side of the inner surface of both side walls of the outer box 6 formed in planar shape.

At this time, the vacuum insulated panel 1 finally becomes a rectangular parallelepiped as shown in Fig. 4 and a longitudinal cross-sectional view from the front of the refrigerator main body to form an outer shape of the refrigerator main body 5. The inner surface of both side walls 6a and 6b of the outer box 6 made of steel sheet is bonded to the inner surface of the outer box 6 while maintaining a predetermined distance from the front and rear and upper and lower ends of the outer box, and the upper surface bent in a substantially inverted U shape from the flat plate. (6c) In the corner bending part 6d of the side end, the bending part 6d does not contact with the bending molding jig 9 by the bending process shown by the dashed-dotted line shown in FIG. An end edge of the panel 1 is positioned and bonded at a position separated by a predetermined distance from the bending molding jig 9 to be positioned.

The configuration may simply be such that the vacuum insulation panel 1 is located above the molding jig 9 during rotational bending, but as shown in FIG. 3, the vacuum insulation panel 1 does not come into contact with the vacuum insulation panel 1 during rotational bending. When the recessed portion 9a is formed in the molding jig 9, the panel 1 can be brought close to the outer box corner portion (bending portion) 6d by the length of the recessed portion, and the surface area of the panel 1 is adjusted. By increasing the insulation efficiency can be improved.

By the above, even if the outer box 6 which adhere | attached the vacuum insulation panel 1 to the inner surface was shape | molded by box-shaped on a shaping | molding line, the rotationally bent vacuum insulation panel 1 contacts the shaping | molding jig 9, and is damaged. Can be prevented.

The outer box 6, to which the vacuum insulation panel 1 is bonded and bent in an inverted U-shape so as to form an upper surface and both sides in a subsequent step, is formed into a box shape by attaching a bottom plate or a back plate. The urethane seal treatment is performed in combination with the inner box 7 forming the storage compartment, and the foam insulation process of the foam insulation 8 made of polyurethane foam with respect to the remaining space between the inner and outer boxes is carried out. (7) and the vacuum insulation panel 1 are integrally bonded together to form a rigid heat insulation cabinet.

If a space exists between the vacuum insulated panel 1 and the outer box 6 of the refrigerator, the outer surface of the outer box is deformed, which causes the cabinet rigidity to weaken as well as the external appearance. Since the unfilled portion of the urethane foam insulation 8, i.e., the voids are formed, becomes a factor of deteriorating the insulation performance, when the vacuum insulation panel 1 is fixedly attached to the outer box of the refrigerator, Care should be taken not to cause gaps.

At this time, since the surface of the vacuum insulation panel 1 has little unevenness and warpage and is smooth, it can be reliably adhered to the outer surface of the outer box 6 without causing a space portion between the high-precision hot melts 4. will be. In addition, since there is no irregularities in the heat insulating space side of the bonded panel 1, the urethane stock solution flows smoothly and is filled without voids, and finally has good heat insulating performance, and at the same time, the foam insulation 8 and the inside The close contact with the box 7, the outer box 6, and the vacuum insulation panel 1 is also hardened, and the cabinet 5 which has great rigidity can be comprised.

In this case, the coverage of the vacuum insulation panel 1 with respect to the surface area of the outer box 6 is 25%, and the effect of reducing the power consumption when compared with a refrigerator having the same capacity as the conventional urethane foam insulation is An improvement of about 15% was recognized. This is considered to be a result of the heat insulation efficiency being improved as described above in that the installation portions are both side walls having a large flat plate-like area, and the vacuum insulation panel 1 is a single panel having the largest area.

In addition, as a result of a predetermined test on the rigidity of the cabinet, a result of the rigidity being improved rather than the conventional one was obtained. This is also considered to have caused a reinforcing action in that the vacuum insulation panel 1, which is a large area and a rigid structure, is provided in the vertical direction in close contact with both side walls of the outer box 6.

Further, at 15% coverage of the vacuum insulated panel, only 4% of the power saving effect was obtained as a result of the same comparative test as described above, and the cabinet rigidity was almost different from the conventional one. In addition, although the power saving effect when the coverage was set at 54% was improved by 24% compared with the prior art, the cabinet's stiffness test resulted in deterioration compared with the conventional product.

Considering the above results, when the coverage of the vacuum insulation panel is too small, such as about 15%, the effect on power saving or rigidity is hardly obtained. On the contrary, when the coverage of the vacuum insulation panel exceeds 50%, The power saving effect can be achieved, but compared with the case of 25% coverage, the power saving effect corresponding to the panel usage is not obtained. On the contrary, since the panel covering area is too much for the cabinet stiffness, the stiffness is deteriorated. In conclusion, it is concluded that the cost-effectiveness of using a totally expensive vacuum insulation panel is low.

On the other hand, like the present invention, the glass insulation mat 1a is used as the core material, and the vacuum insulation panel 1 having a thermal conductivity of 0.003 W / mK or less at the center of the panel is 20% or more with respect to the outer surface area of the refrigerator cabinet 5. In the case of bonding at a coating rate, the improvement of thermal insulation and stiffness strength using a vacuum insulating panel may be expressed with respect to the urethane foam in the past, and when a plurality of vacuum insulating panels are installed by setting the coating rate at 50% or less. Since the thermal insulation effect in the state of the highest efficiency is obtained by preventing the fall of the efficiency of the product, it is not only cost effective, but also prevents sticking of the panel, and does not interfere with the filling action of the urethane foam 8. It is possible to suppress the occurrence of unfilled portions and voids, and to obtain an effect of improving cabinet rigidity by providing a vacuum insulation panel.

In addition, when the thermal conductivity exceeds 0.003 W / mK, it is necessary to further increase the panel coverage to secure the insulation performance and to reduce the power consumption. In this case, the cabinet stiffness, cost, and urethane foam filling are required. Performance cannot be maintained.

In addition, it is not limited to the inner surface of the outer box 6, and high temperature pipes, such as a condensation pipe of a refrigeration cycle, should not be installed in the same plane in which the vacuum insulation panel 1 is installed. As described in the background art, the heat of the outer box 6 is conducted in the thickness direction of the heat insulation wall through the circumference of the airtight container 1b of the panel 1, and a high temperature heat dissipation pipe exists on the installation surface. Since the heat insulation effect is drastically reduced by the heat conduction from the lower surface pipe, it is necessary not to install a high temperature member in the vicinity of the vacuum insulation panel 1.

In the above embodiment, the vacuum insulated panel has been described as being bonded with a hot melt adhesive 4. However, the adhesive means is not limited to a hot melt adhesive, but may be adhered to each other by a double-sided adhesive tape. It is adhered almost to the front surface and is evenly held against the cabinet surface.

In addition, the bonding position with respect to the inner surface of the cabinet of the vacuum insulation panel 1 is not limited to only both sides of the outer box 6, as in the above embodiment, the upper plate inner surface formed in the shape of a plate or a back plate formed of a separate sheet, or When used on a surface having a relatively large area in the shape of a flat plate such as the inside of a refrigerating door, it is easy to install and obtain a good thermal insulation effect, while maintaining the filling performance of the urethane foam 8 to the remaining space and securing rigidity. Although the above advantages are not obtained around the machine room in which the bottom plate, the refrigerant compressor, or the like having a complicated shape are installed, they are not employed.

In addition, the refrigerator employing the vacuum insulation panel 1 is not limited to the home, but can be similarly applied to the construction of insulation cabinets such as for business, showcases, and vending machines.

According to the present invention, it is possible to improve the thermal insulation performance and to reduce the power consumption, or to improve the thermal insulation efficiency of the refrigerator provided with the vacuum insulation panel and to reduce the cost in order to increase the storage volume.

1 is a schematic cross-sectional view of a vacuum insulation panel showing one embodiment of the present invention;

Figure 2 is a schematic diagram showing a vacuum forming step of the vacuum insulation panel of Figure 1,

3 is a side cross-sectional view showing a molding state of an outer box in which the vacuum insulation panel of FIG. 1 is installed;

4 is a cross-sectional view from the front of the refrigerator main body in which the vacuum insulation panel of FIG. 1 is installed;

5 is a longitudinal sectional view of FIG. 4;

6 is a sectional view showing the basic structure of the vacuum insulation panel, and

7 is a comparative graph showing the difference between the vacuum degree and the thermal conductivity by the core material.

* Explanation of symbols for the main parts of the drawings

1: vacuum insulation panel 1a: core material

1b: air repellent container 1c: heat adhesive

2: vacuum forming apparatus 3: vacuum chamber

4: hot melt adhesive 5: refrigerator body

6: outer box 6a, 6b: side part

6d: Bend 7: Inner Box

8: foam insulation 9: bending molding jig

9a: concave

Claims (7)

A glass insulation mat is used as a core material to be stored in an airtight container, and the vacuum is evacuated. The vacuum insulation panel, which is a panel body, is adhered to the inner surface of the insulation space of the refrigerator cabinet, and the polyurethane foam is foamed and filled in the remaining space. The refrigerator according to claim 1, wherein the vacuum insulation panel is bonded to the outer surface area of the refrigerator cabinet at a coverage ratio of 20% or more and less than 50%. The method of claim 1, A refrigerator, characterized in that one vacuum insulating panel is provided on each side of the cabinet. The method of claim 1, A refrigerator characterized by applying a hot-melt adhesive to almost the entire surface of one side or attaching a vacuum insulation panel to which an adhesive tape is attached on the inner surface of an outer box. The method of claim 3, wherein Refrigerator, characterized in that the vacuum insulation panel is attached only to the inner surface of both sides of the outer box. The method of claim 3, wherein Refrigerator, characterized in that no condensation pipes in the refrigeration cycle is installed on the inner surface of the cabinet to install the vacuum insulation panel. The method of claim 1, A refrigerator characterized in that the thermal conductivity of the vacuum insulation panel is less than 0.003W / mK at the center of the panel. The method of claim 1, And an end edge of the vacuum insulation panel attached to the inner surface of the outer box is separated from the ridge position of the upper corner of the outer box, and the vacuum insulation panel is not placed in contact with the corner bending jig after bending.