JP2007139384A - Refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerator with a temperature switch chamber of a relatively small capacity in it which improves volumetric efficiency by enabling a vacuum insulating panel used for its insulating separation walls to change its thermal conductivity and reduces thickness of the insulating separation walls wherein electric power consumption is reduced by improving efficiency of insulation performance and reducing use of a heater. <P>SOLUTION: In the refrigerator with the temperature switch chamber 7 which can switch inside of a chamber to a plurality of cooling temperature bands at least from a freezing temperature band to a cooling temperature band, the vacuum insulating panel 15 is provided for a part of the separation walls 6, 9, 14 between the temperature switch chamber and other storing chambers 5, 8, 10 and devices 21, 22 for enabling inner pressure in the vacuum insulating panel to change are provided in the refrigerator. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a refrigerator, and more particularly, to a refrigerator using a vacuum heat insulating panel as a heat insulating material for a peripheral wall of a temperature switching chamber.

  Conventionally, as a heat insulating material for a heat-insulating cabinet in a refrigerator, it has been mainstream to use a polyurethane foam that has low thermal conductivity and has rigidity integrated with an outer box and an inner box constituting the cabinet by foam filling, In recent years, vacuum as a heat insulator has been used to further improve the heat insulation performance of refrigerator cabinets and reduce power consumption by preventing heat leakage, or by reducing the heat insulation wall thickness to improve volume efficiency as a refrigerator. Some insulation panels have been put to practical use.

  As an example of application to a refrigerator, the vacuum heat insulation panel (55) having the basic configuration shown in FIG. 7 is relatively low of about 1 to 100 Pa, which suppresses material costs, facilitates maintenance of exhaust and vacuum, and obtains long-term reliability. In order to function at a high internal pressure, the core material (56) is made of open-cell resin foam, inorganic fine powder, and fiber that can form a micro space and maintain its form under atmospheric pressure. The material (56) is covered with a gas barrier container (57) obtained by laminating a synthetic resin film and aluminum foil, the inside of the container (57) is evacuated, and then the opening is heat sealed (57a) to be sealed. . In particular, a vacuum heat insulation panel using an ultrafine glass wool having a fiber diameter of several μm or less as a core material (56) has been suitably used because it can realize a low thermal conductivity of 2 mW / mk or less.

  The mounting structure to the refrigerator uses a method in which a large flat panel is attached to a heat insulating space such as the side, back, or ceiling of the cabinet, and a foam insulation such as urethane foam is filled in the space between the opposing wall surface. ing. However, arrangements other than large planes such as the side surfaces are divided arrangements with small panels adapted to individual shapes, which not only reduces the coverage as a vacuum heat insulation panel, but also the influence of heat bridges on the panel end faces. There is a problem that the heat insulation effect as a whole is greatly reduced.

  Moreover, since the refrigerator has an average product life of 10 years or more, it is caused by outgas generated from the core material (56) and permeated gas entering the inside from the sealing surface or surface of the gas barrier container (57). In order to maintain the degree of vacuum by suppressing deterioration over time due to an increase in internal pressure and maintain the performance of the vacuum insulation panel (55) over the long term, along with the performance improvement of the gas barrier container (57), titanium, magnesium, etc. Intrusion gas and internal generation by adopting getter agent (60) that consists of metal, barium and other alloys, oxides such as zeolite, activated carbon, etc. and adsorbs moisture, oxygen, nitrogen and other air components and hydrogen. Gas removal is generally performed, and Patent Document 1 discloses a method for maintaining an internal pressure by a continuous getter regeneration means.

On the other hand, in order to ensure the temporal stability of the vacuum heat insulation panel, it is also considered to detect an increase in the pressure inside the panel and exhaust the vacuum pump to keep the internal pressure below a predetermined value (for example, patents). Reference 2).
JP 2001-132892 A Japanese Patent Publication No. 4-59551

  As described above, various methods have been proposed so far to effectively arrange the vacuum heat insulation panel on the refrigerator wall surface and to ensure stability over time, but in order to effectively use the cooling storage chamber in recent years, Refrigerators equipped with temperature switching chambers that can set one of independent compartments in various cooling temperature zones have been commercialized.

  In the refrigerator, the set temperature of the temperature switching chamber is configured to be switchable from the refrigeration temperature to the refrigeration temperature, and further, there is a case where the heater is heated to be used as a relatively high temperature incubator, and the temperature is switched. Is arbitrarily set by the user, it was necessary to set the heat insulation thickness of the surrounding partition walls constituting the temperature switching chamber to a thickness having heat insulation performance in consideration of the maximum temperature difference.

  And if there are a plurality of temperature switching chambers, the partition wall having the maximum heat insulation thickness will increase, and there will be a disadvantage that the volumetric efficiency with respect to the refrigerator outer shape will be greatly reduced, and the temperature control of each chamber will be complicated, It has become difficult to properly control the temperature and air volume of the cold air supplied to the vehicle simply by opening and closing the damper, and a heater for compensating the indoor temperature needs to be disposed on the low wall surface.

  The present invention has been made in consideration of the above points, and has a relatively small-capacity temperature switching chamber in the cabinet, and by making the thermal conductivity of the vacuum heat insulating panel used for the partition heat insulating wall variable. An object of the present invention is to provide a refrigerator that reduces the partition heat insulation wall thickness, improves volumetric efficiency, and reduces power consumption by efficient heat insulation performance and reduced use of heaters.

  In order to solve the above problems, the present invention provides a refrigerator provided with a temperature switching chamber capable of switching a room to a plurality of cooling temperature zones from at least a freezing temperature zone to a refrigeration temperature zone, and the temperature switching chamber and other storage chambers A vacuum heat insulation panel is disposed on a part of the partition wall, and a device for changing the internal pressure of the vacuum heat insulation panel is provided.

  According to the configuration of the present invention, the thermal insulation thickness of the surrounding wall forming the temperature switching chamber can be reduced by the high thermal insulation performance due to the use of the vacuum thermal insulation panel, and the storage volume efficiency can be improved. By changing the heat insulation performance, the heat leak can be reversed and used for temperature control in the switching room, and the heat amount of the heater that prevents overcooling can be reduced or eliminated, reducing the power consumption. Can contribute.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a refrigerator according to the present invention, and FIG. 2 is a front view in which the door of the refrigerator is omitted, and an outer box (2) that forms an outer shell and an inner box (3) that forms a storage space. A refrigerator compartment (5) having a large storage capacity is arranged above the storage space inside the refrigerator main body (1) made of a heat insulating box body filled with a foam insulation material (4) made of urethane foam or the like in the gap, and below that In the case, a relatively small-capacity temperature switching chamber (7) and an ice making chamber (8) are arranged side by side with a heat insulating partition wall (6).

  Below the temperature switching chamber (7) and the ice making chamber (8), a vegetable room (10) partitioned by a heat insulating partition wall (9) is provided in the same manner as described above, and the freezer room (11) is insulated at the bottom. It is divided and arranged.

  Each storage room has its front opening closed by a dedicated opening / closing door, and the opening of the refrigerating room (5) having the largest storage capacity arranged at the top is pivoted on one side or both sides by hinges. It opens and closes in a rotating manner with a sheet or double doors, and the temperature switching room (7), ice making room (8), vegetable room (10) and freezer room (11) below the refrigeration room have a drawer door system. This is a well-known configuration.

  In the cooler room formed in the back space of the vegetable room (10), a refrigeration cooler (12) and a refrigeration cooler (13) are placed one on top of the other, and each of the above is provided by a dedicated fan. The storage room is cooled to a predetermined temperature.

  For the temperature switching chamber (7), open / close control of the operation of the refrigeration cycle and the damper provided at the cold air outlet according to the detected value of the sensor that detects the air temperature in the room, and introduction based on arbitrarily set temperature specifications Adjusting the amount of cold air, the insulated room is refrigeration temperature below -18 ℃ to weak refrigeration temperature of -8 ℃, partial freezing temperature of -3 ℃, chilled temperature of about 0 ℃, refrigeration temperature of about 2 ℃ The temperature is controlled to a predetermined set room temperature by switching to a vegetable storage temperature of 5 ° C. and further to a wine storage temperature of about 8 ° C.

  And in the heat insulation partition wall (14) partitioning between the ice making chamber (8) around the temperature switching chamber (7) and the upper and lower storage chambers (6) (9), A vacuum insulation panel (15) is provided. This vacuum heat insulation panel (15) is formed by forming a gas barrier container with a stainless steel sheet and using a core material made of ultra-fine glass wool.

  As shown schematically in FIG. 3, the vacuum heat insulation panel (15) is formed by matting glass wool, which is an ultrafine glass fiber cotton material having a fiber diameter of several μm or less, without using a binder. The core material (16) is formed.

  The gas barrier container (17) for storing the core material (16) is formed by drawing a stainless steel sheet having a thickness of about 30 to 100 μm in advance into a shallow dish shape having a flange (18a) at the periphery, This is press-molded into a container (18) formed in a substantially U shape to match the surrounding shape of the temperature switching chamber (7), and a flange (18a) on the opening surface of the U-shaped container (18). It is comprised from the cover body (19) by the stainless steel sheet | seat bent and formed in the shape which obstruct | occludes the opening of a container part.

  The gas barrier container (17) is integrally formed in a substantially U-shape so that the vacuum insulation panel coverage with respect to the total insulation area can be improved and the panel end face compared to the conventional divided small panel configuration. This is to reduce the occurrence of heat bridges through the wire and greatly suppress heat leakage. The shape is not limited to the U shape but may be an L shape, and a thin panel having a thickness of about 10 to 12 mm is provided. By doing, the effect of maintaining the heat insulation effect satisfactorily can be obtained.

  After the glass wool core material (16) formed into a mat shape by press molding is pushed into the container (18) and stored, the deterioration with time due to outgas generated from the core material or permeated gas entering the inside is suppressed. The getter agent (20) that adsorbs moisture and gas is sealed, the inside is evacuated, and the lid (19a) of the dish-like container and the peripheral edge of the lid (19) are in contact with each other to close And the heat insulation panel (15) which hold | maintained the inside of a container in the vacuum pressure reduction state is formed by sealingly connecting the interior space of a container by welding or brazing.

  The vacuum heat insulating panel (5) configured as described above is attached to the inner surface of the partition walls (6), (9), and (14) forming the temperature switching chamber (7) at a predetermined position with hot melt adhesive or double-sided tape. The outer box (2) and the inner box (3) are provided in the gap between the partition wall (6) (9) (14) and the inner surface of each partition wall (6) (9) (14) facing the vacuum heat insulation panel (15) after being attached. A part of the undiluted solution of polyurethane foam insulation material (4) injected by in-situ foaming method flows into the gap between the vacuum insulation panel (15) by foaming and solidifying in the same manner as the inside wall of the main body. The partition walls (6), (9), and (14) are embedded and fixed and integrated with the main body side.

  The vacuum heat insulation panel (15) is connected to a part of the rear surface of the temperature switching chamber (7) or a vacuum pump (21) installed in the machine room and a leak valve (22). The internal pressure of the vacuum heat insulation panel (15) is varied in accordance with the set temperature of the temperature switching chamber (7) switched by the operation of the refrigerator user at home.

  That is, when the user operates the control panel installed on the door surface or the like to change the specification of the temperature switching chamber (7), the operating time and leak of the vacuum pump (21) for each preset temperature specification The internal pressure of the vacuum heat insulation panel (15) is controlled by the valve opening time of the valve (22), etc., and the temperature switching chamber (7) has a thermal conductivity (λ ) Will change.

  Specifically, when the temperature switching chamber (7) is used with a low temperature specification such as a freezing room temperature, it is stored at a relatively high temperature such as the upper refrigeration chamber (5) or the lower vegetable chamber (10). Since the temperature difference from the room becomes extremely large and higher heat insulation performance is required, the vacuum pump (21) is driven to suck the air inside the vacuum heat insulation panel (15), and the pressure is reduced to 10 Pa or less. It is intended to hold.

  At this time, as shown in part A of FIG. 4 showing the relationship between the internal pressure of the core material (16) of the vacuum heat insulating panel (15) and the thermal conductivity, when held in the pressure region of 10 Pa or less, Its thermal conductivity is 0.006 W / m · K or less. In particular, in the case of the refrigeration specification, the vacuum insulation panel is maintained at the original 0.002 W / m · K level by evacuating, and low heat High heat insulation performance against a large temperature difference can be obtained by conductivity. Therefore, since the effect of blocking heat leakage is great, the room can be easily maintained at the freezing temperature, the load on the cooling operation is reduced, and the power consumption can be reduced.

  In addition, when the temperature switching chamber (7) is set to a relatively high temperature room such as refrigerated room temperature, loosen the leak valve (22) to introduce outside air and reduce the internal pressure of the vacuum insulation panel (15) to about It controls so that it may become 1000 Pa or more. As described above, when the temperature switching chamber (7) has a high temperature specification, the upper refrigeration chamber (5) and the lower vegetable chamber (10) are both in the same temperature zone as the temperature switching chamber (7). The heat insulation performance of the walls (6) and (9) is hardly necessary, and by increasing the internal pressure, the heat conduction of about 0.020 to 0.035 W / m · K as shown in the B part in FIG. It is what you want to rate.

  The actual pressure change is not changed from a few Pa to the atmospheric pressure at which complete leakage occurs. In addition, the heat conduction is taken into account when the temperature is changed to evacuate again to change from refrigeration to refrigeration. A width of up to about 10,000 Pa where the rate is almost constant is sufficient.

  In the above, the inside of the temperature switching chamber (7) having the temperature specification of the refrigerator compartment or the vegetable compartment can be cooled indirectly by heat leakage from the upper and lower chambers (5) and (10) due to high thermal conductivity. Therefore, it is possible to efficiently perform the cooling operation with less load due to reverse use of heat leakage, and it is also possible to maintain the switching chamber (7) in a humid atmosphere by indirect cooling.

  Also, if the heat insulation performance of the temperature switching chamber (7) itself is too high when switching from the refrigeration specification to the refrigeration specification, the room temperature does not easily rise from the refrigeration temperature to the refrigeration temperature. Conventionally, a heating element such as a heater was provided on the bottom wall of the room to perform the operation, and the temperature was forcibly increased by this heat generation, or the set temperature was maintained by preventing overcooling by heating the heater. According to the configuration of the present invention, it is not necessary to arrange and control the heating element, the amount of heat of the heater can be reduced or eliminated, and the load on the refrigeration apparatus can be reduced to save power.

  Further, as shown in FIG. 5 in which the same reference numerals are given to the same parts as those in FIG. 2, the vegetable room (10) portion arranged below the temperature switching chamber (7) in the above embodiment is replaced with the second temperature switching chamber (23 ), The partition wall (24) between the two chambers (23) (11) is placed on the partition wall (24) in consideration of the large temperature difference from the freezer chamber (11) positioned below the When a similar vacuum insulation panel (25) is installed and the second switching chamber (23) is used for refrigeration specifications, the internal pressure of the panel (25) is increased to about 1000 Pa or more and the refrigeration specifications are used. Keeps the thermal conductivity at the original 0.002 W / m · K level of the vacuum insulation panel, and obtains a high thermal insulation performance against a large temperature difference due to the low thermal conductivity.

  In each of the above embodiments, when the temperature switching chambers (7) and (23) are continuously used in the refrigeration specification, the low thermal conductivity is maintained by suppressing the temporal change of the vacuum heat insulating panels (15) and (25). For this reason, the vacuum pumps (21) and (21 ') are driven for a predetermined time, for example, once every week to control the panel internal pressure. The vacuum pump (21) (21 ') requires a cooling operation time of several tens of minutes to one hour in order to change the temperature in the temperature switching chamber (7) (23) by switching the specifications. Any specification that can reduce the internal pressure is acceptable.

Moreover, as shown in FIG. 6, the gas barrier container (37) of the vacuum heat insulation panel (35) is formed of a synthetic resin frame (37a), and the synthetic resin and metal foil are formed along the frame (37a). A laminated film (37b) to be formed is attached by heat sealing, and the same core material (36) is compressed inside the barrier container (37) through an opening formed on one side of the frame (37a). After packing, the opening may be heat-sealed to make it airtight, and the inside may be evacuated.

  With this configuration, the barrier container (37) can be obtained simply by attaching the laminate film (37b) along the edge of the rigid frame (37a) formed in advance, so the core material (36) is filled. The shape can be maintained even in a state where it is not, and a three-dimensional panel form that is not a flat plate can be freely obtained.

  According to the above configuration, when the user desires, the cooled storage item can be stored in a predetermined temperature range according to the respective amount and stored in a cooled state, and the storage volume of the desired storage temperature range can be set according to the situation. In addition to being expandable, the vacuum insulation panel is located on the wall surface around the temperature switching chamber, so it is easily affected by the set temperature difference between each adjacent storage chamber, but can be switched arbitrarily. Since the thermal conductivity changes according to the set temperature of the temperature switching chamber, it is possible to sufficiently shut off heat against the adverse effects of large temperature differences inside and outside the temperature switching chamber, and the cooling efficiency in the storage chamber Can contribute to the reduction of power consumption.

  In addition, although the vacuum heat insulation panel shape was demonstrated as what was made into the shape like U shape or L shape in the said Example, it may not be restricted to this but may be formed and arrange | positioned with a flat metal panel. Needless to say, it is good.

  In each of the above embodiments, the heat insulation wall is formed by foaming and filling polyurethane foam without using the vacuum heat insulation panel except for the temperature switching chamber portion. You may apply to what arrange | positioned the normal vacuum heat insulation panel.

  INDUSTRIAL APPLICATION This invention can be utilized for the refrigerator which provided the vacuum heat insulation panel in the surrounding heat insulation wall with the temperature switching chamber.

It is a longitudinal cross-sectional view of the refrigerator which shows one Embodiment of this invention. It is a longitudinal cross-sectional view from the front which shows the arrangement | positioning state of the vacuum heat insulation panel of the refrigerator in FIG. It is sectional drawing which shows schematic structure of the vacuum heat insulation panel in FIG. It is a graph which shows the relationship between the internal pressure of a vacuum heat insulation panel, and thermal conductivity. It is sectional drawing of the same part as FIG. 2 which shows the other Example of this invention. It is a schematic perspective view which shows the other Example of a vacuum heat insulation panel. It is sectional drawing which shows the basic composition of a vacuum heat insulation panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Refrigerator body 2 Outer box 3 Inner box 4 Insulation material 5 Refrigeration room 6, 9, 14, 24 Insulation partition wall 7 Temperature switching room 8 Ice making room 10 Vegetable room
15, 25, 35 Vacuum insulation panel 16, 36 Core material 17, 37 Gas barrier container
18 Container 19 Lid 20 Getter agent
21 Vacuum pump 22 Leak valve 23 Second temperature switching chamber

Claims (6)

  In a refrigerator provided with a temperature switching chamber capable of switching the room to a plurality of cooling temperature zones from at least a freezing temperature zone to a refrigeration temperature zone, vacuum insulation is provided on at least a part of a partition wall between the temperature switching chamber and another storage chamber A refrigerator comprising a panel and a device for changing the internal pressure of the vacuum heat insulating panel.   The refrigerator according to claim 1, wherein a vacuum pump and a leak valve are arranged so as to communicate with the vacuum heat insulation panel, and the internal pressure of the vacuum heat insulation panel is changed in accordance with a set temperature of the temperature switching chamber.   The refrigerator according to claim 2, wherein the vacuum evacuation in the vacuum heat insulation panel by the vacuum pump is performed at regular intervals.   The heat conductivity of the vacuum heat insulation panel due to the change in internal pressure is set at least at two levels, the low heat conductivity range is 0.006 W / m · K or less, and the high range is 0.020 to 0.040 W / m · K. The refrigerator according to claim 1 or 2.   The refrigerator according to claim 1 or 2, wherein the vacuum heat insulating panel is integrally formed with at least two planes of a horizontal portion and a bent portion. A vacuum insulation panel that varies the internal pressure is disposed on at least a part of the partition wall between the temperature switching chamber and the other storage chamber, and a vacuum insulation panel with a fixed thermal conductivity is disposed on at least a part of the outer wall of the main body. The refrigerator according to claim 1, wherein the remaining space is foam-filled with urethane foam heat insulating material.

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