JP2011226749A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem on degradation of heat insulating performance and design caused by generation of unevenness of a surface of a heat insulating panel in the heat insulation structure panel of a refrigerator, caused by uncharging and unevenness in density of foamed resin caused by deflection and remaining of the air inside the panel and the generated gas inside the panel in injecting and foaming the resin in a manufacturing process.SOLUTION: Holes of φ0.25 mm or less are formed on the periphery of a high-reflection area zone of corner curved sections of four corners of a product at a metallic surface side of the heat insulation structure panel of the refrigerator. Thus the air inside and the excess generated gas escape without enclosed in foaming a heat insulating resin, and appearance quality is not degraded by avoiding high brightness reflection area of the curved face of the heat insulating panel appearance. The gas escape holes are formed in a throttling and bending process in press work of the metallic thin panel.

Description

  The present invention relates to a heat insulating casing used for a refrigerator or a freezer, and particularly relates to a refrigerator excellent in heat insulating performance and design of product appearance.

  Conventionally, as this kind of refrigerator, there is a thing shown by patent documents 1, for example. The structure will be described with reference to FIGS. FIG. 7 is a sectional view of a conventional heat insulation structural panel for a refrigerator, and FIG. 8 is an enlarged sectional view of the heat insulation structural panel for a refrigerator in FIG.

  7 and 8, 1 is a refrigerator body, 2 is a refrigerator door, 3 is a metal panel on the refrigerator door surface, and 4 is a resin liner on the back surface of the refrigerator door. A space between the metal panel 3 and the resin liner 4 is filled with a heat insulating foamed resin 5 such as urethane foam in order to exhibit heat insulating performance. Similarly, in the refrigerator main body 1, a space formed by the metal plate 7 and the resin liner 8 is also filled with a heat insulating foamed resin 9 such as urethane foam. The compressor 10 is attached to this refrigerator, and the cold air heat-exchanged in the evaporator 11 is sent to the freezer compartment 12 by a fan. A refrigerator compartment 13 partitioned by a partition plate 14 is formed below the refrigerator.

  In this way, the performance of a heat-insulated structural panel that is thermally shielded from the outside air is the first factor that determines energy-saving performance and efficiency, and the refrigerator exhibits thermal insulation performance between the outer metal panel and the inner resin liner. It is required to uniformly form a foamed urethane (heat insulating foamed resin) layer. For the formation of this foamed urethane layer, a method is used in which a raw solution of foamed urethane before foaming is injected into the gap between the metal panel and the resin liner, and then foamed by chemical reaction foaming about 30 to 40 times and self-filled. . At this time, in order to effectively discharge the air remaining between the metal panel 3 and the resin liner 4 and the generated gas from the heat insulating foamed resin surface, the resin liners 4 and 8 are provided with gas vent holes 18.

  The refrigerator door 2 of this conventional refrigerator is a manufacturing process for injecting and foaming a heat insulating foamed resin. First, the resin is injected into the center, the resin foams and flows around the periphery, and finally the peripheral corners and ribs are filled. Is done. At this time, the air present in the space filled with the resin and the presence of excess foaming gas generated from the flow front at the time of foaming become uniform non-uniform back pressure against foaming pressure of about 10-20 kpa at the end. This prevents the formation of a heat insulating structure having a high foam density. At the same time, an unfilled state in which the resin is not completely filled is generated. For this, a gas vent hole 18 or a gas vent groove 19 is provided in the peripheral portion of the door 2 to reduce the back pressure.

JP-A-8-14733 (FIG. 1)

  However, in the conventional refrigerator door, there is a problem that the gas vent hole 18 and the gas vent groove 19 for lowering the back pressure can be arranged only at the rib portion of the resin liner 4 or the outer edge portion of the resin liner 4. It was.

  This problem is caused by the fact that the formation of the gas vent structure for the metal panel 3 is not easy in processing, and that the design appearance cannot be freely arranged.

  As the heat insulating foamed resin, for example, urethane resin and the like, the foaming flow proceeds particularly in a low viscosity state. Therefore, a large amount of resin leaks in a hole of Φ1.0 mm or more suitable for processing as a gas vent hole.

  The present invention was made in order to solve the problems of the above-described technology, and provides a refrigerator excellent in heat insulation performance and design without causing unfilled defects without impairing the design. Objective.

  In order to achieve the above object, the refrigerator according to the present invention is a refrigerator including a door formed by filling a space formed between an outer plate and an inner plate with a heat-insulating foamed resin. A hole is formed in the curved surface portion of the outer plate.

  As described above, according to the present invention, it is possible to easily fill the heat insulating foamed resin to the end of the heat insulating panel product, prevent unfilled defects, and provide a refrigerator that has excellent design and does not impair the product appearance. Is possible.

Sectional drawing of the heat insulation structural panel for refrigerators in Embodiment 1 of this invention The expanded sectional view of the heat insulation structure panel for refrigerators in Embodiment 1 of this invention The figure which shows the relationship between the gas vent hole diameter and heat insulation foaming resin mole amount in this invention The figure which shows the principal part of the vent hole provided in the heat insulation structure panel surface corner part by this invention The figure which shows the principal part of the thin wall groove | channel provided in the heat insulation structural panel for refrigerators of Embodiment 1 of this invention, and a vent hole. The figure which shows the principal part of the stepped gas vent hole provided in the heat insulation structure panel for refrigerators of Embodiment 1 of this invention. Sectional drawing of the heat insulation structural panel for the conventional refrigerator described in patent document 1 The expanded sectional view of the conventional heat insulation structure panel for refrigerators described in patent documents 1

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals, and description thereof is omitted as appropriate.

(Embodiment 1)
1 is a cross-sectional view of a heat insulating structural panel for a refrigerator according to Embodiment 1 of the present invention, and FIG. 2 is an enlarged cross-sectional view of the heat insulating structural panel of FIG. FIG. 3 is a graph in which the amount of resin leakage due to the diameter of the vent hole and the internal pressure is calculated. FIG. 4 is a diagram in which the gas vent holes in the first embodiment of the present invention are arranged on the surface of the heat insulating structure panel, and FIGS. 5 and 6 show the cross-sectional shapes of the gas vent holes according to the first embodiment of the present invention. .

  In FIG. 1, 1 is a refrigerator body, 2 is a refrigerator door, 3 is a metal panel (outer plate) on the refrigerator door surface, and 4 is a resin liner (inner plate) on the back surface of the refrigerator door. The space between the metal panel 3 and the resin liner 4 is filled with a heat insulating foamed resin 5 such as foamed urethane in order to exhibit heat insulating performance as a heat insulating casing. Similarly, in the refrigerator main body 1, a space formed by the metal plate 7 and the resin liner 8 is also filled with a heat insulating foamed resin 9 such as urethane foam.

  The heat insulating foamed resin 5 is a resin such as polyurethane generally generated by a chemical reaction between a polyol and an isocyanate. A compressor 10 is attached to the refrigerator, and cold air heat-exchanged in the evaporator 11 is sent to the freezer compartment 12 by a fan. A refrigerator compartment 13 partitioned by a partition plate 14 is formed below the refrigerator.

  In FIG. 1, the vent hole 6 of the first embodiment is provided in a peripheral portion that is a curved portion of the metal panel 3, and air and extra generation in the heat insulating structural panel are generated during foam molding of the heat insulating foam resin. Gas can be effectively released to the outside. Further, the vent holes 6 are formed intensively at the corner of the upper curved surface portion (upper side in FIG. 1) and the corner of the lower curved surface portion (lower side in FIG. 1) when it becomes a refrigerator door. It is preferable that it is not formed on the side surface or the upper and lower surfaces. This is because when it is formed on the side surface or the upper and lower surfaces when it becomes a refrigerator door, there is a possibility that the design on the product appearance may be impaired even slightly.

  In addition, if necessary, the air and the generated gas in the heat insulation structure panel are more effectively released to the outside by combining with the gas vent hole 18 and the gas vent groove 19 provided in the resin liner 4 of the conventional example. It is also possible.

  The vent hole 6 can be formed by a drawing process or a bending process when the metal panel 3 is pressed.

  As for the size of the vent hole 6, a minimum diameter that does not allow a large amount of resin to be exposed to the outside even when foaming molding pressure is applied is required. FIG. 3 is a graph showing the relationship between the diameter and the amount of the heat insulating foam resin.

  In FIG. 3, the three types of curves plot the diameter of the vent holes and the amount of heat-insulating foamed resin when the internal pressure is 5, 10, and 15 kPa, respectively. The non-defective area (area that does not need to be corrected), the correctable area, and the defective area are defined in the process. Here, it can be determined from the non-defective region that the maximum vent hole diameter should be φ0.25 mm or less.

  It is effective to provide the gas vent hole 6 around the filling end of the heat insulating foamed resin of the heat insulating structure panel. However, in order to secure the design of the appearance of the product, an area that can be arranged as shown in FIG. It is preferable to define.

  In FIG. 4, 15 indicates the boundary ridge line between the curved surface portion and the flat surface portion of the peripheral corner of the heat insulating structure panel, and 16 indicates the vicinity of the center of the curved surface portion (from the curved surface center line of the curved surface portion to the curved surface portion). This represents a high-intensity reflection band existing in the entire width 1/3 or less. This part has a particularly high brightness due to the reflection of external light in the appearance of the heat insulating structure panel, and is also a characteristic line on the product appearance.

  6a and 6b represent the arrangement of the vent holes related to the present invention provided in the peripheral curved surface portion. 6 a is on the extension of the boundary ridge line 15, and 6 b is provided on the outline of the high-intensity reflection band 16.

  In the present invention, it is a feature that a vent hole having a diameter of 0.25 mm or less is provided in the heat insulating structure panel. However, in the curved surface portion of the heat insulating structure panel, for example, when the gas vent hole 6 is arranged in the high-intensity reflection band 16, Due to the difference in contrast between the high-intensity reflection band 16 and the gas vent hole 6, the gas vent hole 6 becomes very conspicuous, which may impair the design of the product appearance. In order to avoid this, it is effective to provide a gas escape hole 6b on the contour line of the high-intensity reflection band 16. The reason is that a person's line of sight concentrates on a part with high brightness. In the first embodiment, the human line of sight concentrates on the high-intensity reflection band 16, and the normal reflection luminance part immediately (next) appears to be emphasized in darkness due to the contrast difference. This is because concentration of human gaze can be avoided. Similarly, since the brightness of the reflected light gradually decreases at the boundary ridge line 15 that becomes the boundary between the flat surface portion and the curved surface portion, it becomes difficult to focus and the gas vent hole 6 becomes difficult to stand out. Therefore, in the first embodiment, the gas vent hole 6 is disposed between the outline of the high-intensity reflection band 16 and the boundary ridge line 15 in order to improve the design on the product appearance. Thereby, while forming in the surface of a refrigerator door, while preventing the unfilling defect, the door for refrigerators which maintained the design property on the external appearance of a product is realizable.

  Here, in this Embodiment 1, the shape of the gas vent hole 6 formed in a heat insulation structure panel is considered.

  For the processing of a gas vent hole with a diameter of 0.25 mm or less on a heat insulating structure panel, it is desirable that the diameter is larger and the metal panel is thinner in consideration of the strength of the punch tool in the press processing at the time of mass production. . In order to make these compatible, in another embodiment of the first embodiment of the present invention, as shown in FIG. 5, a thin groove processing is applied to a portion where the gas vent hole on the back surface of the metal panel is arranged, and the press is locally performed. The processing load is reduced.

  In FIG. 5, reference numeral 17 denotes a thin groove portion provided to make the metal panel partially thin, and 6c denotes a cross section of a gas vent hole formed in the central portion of the groove.

  Similarly, in order to increase the strength of the pressing tool and reduce the processing load, in another embodiment of the first embodiment, the vent hole may have a stepped hole shape as shown in 6d of FIG.

  FIG. 6 is a diagram showing a cross-section of the vent hole 6d having a stepped structure with respect to the shape of the vent hole formed in the metal panel.

  By providing the vent hole configured in this manner on the surface of the heat insulating structure panel of the refrigerator, the heat insulating foamed resin can be easily filled up to the end (tip) of the heat insulating structure panel, and unfilled defects can be prevented. Furthermore, by devising the arrangement location as in the present invention, the design of the product appearance of the refrigerator is not impaired.

  Also, by providing a vent hole on the surface of the heat insulation structure panel, the pressure inside the heat insulation structure panel during foaming flow is maintained at atmospheric pressure, so the density of the foam cells is made uniform in the heat insulation structure panel. The heat insulation performance can be secured over the entire surface of the heat insulation structure panel of the refrigerator.

  The refrigerator of the present invention is excellent in heat insulation performance and design, and can be applied to consumer and industrial general equipment including refrigerators and refrigeration facilities.

DESCRIPTION OF SYMBOLS 1 Refrigerator main body 2 Refrigerator door 3 Metal panel 4, 8 Resin liner 5, 9 Heat insulation foaming resin 6, 18 Degassing hole 7 Metal plate 10 Compressor 11 Evaporator 12 Freezer compartment 13 Refrigeration compartment 14 Partition plate 15 Boundary ridge 16 High brightness Reflection band 17 Thin groove 19 Degassing groove

Claims (7)

In a refrigerator including a door formed by filling a heat insulating foamed resin in a space formed between an outer plate and an inner plate,
A refrigerator in which a hole is formed in a curved surface portion of the outer plate serving as a surface of the door. 2. The refrigerator according to claim 1, wherein the hole is a gas vent hole for releasing a gas generated when the heat insulating foamed resin is foamed to the outside. The refrigerator according to claim 1 or 2, wherein the hole has a diameter of 0.25 mm or less. The outer plate is composed of the curved surface portion and a flat surface portion,
The range from the curved surface center line of the curved surface portion to the width 1/3 of the entire curved surface portion is defined as a high luminance reflection band, and the hole is formed in the curved surface portion other than the high luminance reflection band. Item 5. The refrigerator according to any one of Items 1 to 4. The refrigerator according to claim 4, wherein the hole is formed along an outline of the high-intensity reflection band. The refrigerator according to any one of claims 1 to 5, wherein a thin groove portion having a thickness thinner than other regions is formed on the rear surface of the outer plate, and the hole is formed in the thin groove portion. The hole is a stepped hole having a larger diameter on the back surface of the outer plate than the surface of the outer plate, and the through hole diameter of the stepped hole is φ0.25 mm or less. Refrigerator.

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