refrigerator

Abstract

To provide a refrigerator that cools a freezing chamber and a refrigerating chamber by using a first cooling part and a second cooling part, and can reliably defrost the second cooling part without using a defrosting heater.SOLUTION: A refrigerator comprises a first cooler 14, a defrosting heater 21 for heating at least the first cooler 14, a freezing chamber fan 9a for pressurizing air cooled by the first cooler 14, a duct through which the air pressurized by the freezing chamber fan flows, a heat transfer plate (second cooler) 200 arranged in the duct or a region through which the air passed through the duct flows, and a refrigerating chamber 2 housing the air cooled by the heat transfer plate 200. The heat transfer plate 200 cools the air in the refrigerating chamber 2 to a temperature equal to or lower than a dew point or a frost point. When frost or condensation occurs on the heat transfer plate 200, the defrosting heater 21 is made to generate heat; the freezing chamber fan 9a is driven; and air heated by the defrosting heater 21 is blown toward the heat transfer plate 200.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] This invention relates to a refrigerator for refrigerating and freezing food and beverages. [Background technology]

[0002] As a technology for achieving defrosting operation in a refrigerator with two evaporators, for example, the refrigerator described in Japanese Patent Publication No. 2000-146400 (Patent Document 1) is known.

[0003] The refrigerator described in Patent Document 1 includes a compressor, a condenser, a refrigeration throttling mechanism, a refrigeration evaporator corresponding to the refrigerator compartment, a freezing throttling mechanism, a freezing evaporator corresponding to the freezer compartment, and a refrigerant flow path connecting these.

[0004] Furthermore, by switching the refrigerant flow path using a switching valve, alternating cooling operation can be performed, which alternates between a refrigeration mode in which refrigerant flows to the refrigeration evaporator and the freezing evaporator via a refrigerant throttling mechanism, and a freezing mode in which refrigerant flows only to the freezing evaporator via a freezing throttling mechanism.

[0005] Furthermore, it includes a refrigeration fan that blows air cooled by a refrigeration evaporator into the refrigerator compartment, a refrigeration fan that blows air cooled by a freezing evaporator into the freezing compartment, a defrost heater for the freezing evaporator, and a control means that performs a freezing mode after the pre-cooling operation is completed, followed by a defrosting operation.

[0006] In the control system, the refrigeration mode is executed after the pre-cooling operation is completed, which empties the refrigerant inside the refrigerator evaporator, making it easier for the temperature of the refrigerator evaporator to rise and thus shortening the defrosting operation time. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2000-146400 [Overview of the project] [Problems that the invention aims to solve]

[0008] Incidentally, in the configuration of Patent Document 1, the freezer compartment and the refrigerator compartment are cooled using a refrigeration evaporator (first cooling section) and a refrigerator evaporator (second cooling section). Then, during defrosting operation, after a pre-cooling operation, the defrost heater of the refrigeration evaporator and the defrost heater of the refrigerator evaporator are activated to defrost the refrigeration evaporator and the refrigerator evaporator. This ensures reliable defrosting of the refrigeration evaporator and the refrigerator evaporator.

[0009] However, equipping both the freezing evaporator and the refrigeration evaporator with their own defrost heaters presents the challenge of increased product costs.

[0010] The object of the present invention is to provide a refrigerator that enables reliable defrosting of the second cooling section without using a defrost heater for the second cooling section. [Means for solving the problem]

[0011] To solve the above problems, for example, the configuration described in the claims is adopted. The present invention includes multiple means for solving the above problems, but to give one example, it comprises a first cooling unit, a heating unit that heats at least the first cooling unit, a fan that pressurizes the air cooled by the first cooling unit, a duct through which the air pressurized by the fan flows, a second cooling unit arranged in the duct or in the region through which the air that has passed through the duct flows, and a storage chamber that contains the air cooled by the second cooling unit, wherein the second cooling unit cools the air in the storage chamber to a temperature below the dew point or frost point of the air, and while frost or condensation has formed on the second cooling unit, it generates heat in the heating unit and drives the fan to blow the air heated by the heating unit toward the second cooling unit. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a refrigerator that can reliably defrost the second cooling section without using a dedicated heat-generating section. Furthermore, other problems, configurations, and effects will be clarified by the following description of embodiments. [Brief explanation of the drawing]

[0013] [Figure 1] This is a front view of a refrigerator according to an embodiment of the present invention. [Figure 2] Figure 1 is a longitudinal cross-sectional view of a refrigerator. [Figure 3] Figure 1 is a front view showing the internal configuration of the refrigerator. [Figure 4] This figure shows a freezer compartment damper in a refrigerator according to an embodiment of the present invention. [Figure 5] This is an exploded perspective view showing the airflow path in the refrigerator compartment of a refrigerator according to an embodiment of the present invention. [Figure 6] This is a schematic diagram showing the airflow configuration of a refrigerator according to an embodiment of the present invention. [Figure 7] This is a diagram showing the configuration of the refrigeration cycle of a refrigerator according to an embodiment of the present invention. [Figure 8] This flowchart shows the basic control of the cooling operation of a refrigerator according to an embodiment of the present invention. [Figure 9] This graph shows an example of temperature changes during cooling operation of a refrigerator according to an embodiment of the present invention. [Figure 10] This flowchart shows the basic control of the defrosting operation of a refrigerator according to an embodiment of the present invention. [Figure 11] This graph shows an example of temperature changes during defrosting operation of a refrigerator according to an embodiment of the present invention. [Figure 12] Figure 2 is a block diagram showing the configuration of the control device. [Modes for carrying out the invention]

[0014] Embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the following embodiments, and various modifications and applications are also included within the scope of the technical concept of the present invention.

[0015] Embodiments of the present invention will be described below with reference to Figures 1 to 12. In the following description, when viewing the refrigerator from the front, the side visible on the right will be referred to as the right side, and the side visible on the left will be referred to as the left side.

[0016] A refrigerator 1 according to an embodiment of the present invention will be described with reference to Figure 1. Figure 1 is a front view of a refrigerator 1 according to an embodiment of the present invention.

[0017] As shown in Figure 1, the insulated box 10 of the refrigerator 1 has storage compartments in the following order from top to bottom: a refrigerator compartment 2, ice-making compartments 3 located on the left and right sides, an upper freezer compartment 4, a lower freezer compartment 5, and a vegetable compartment 6.

[0018] Refrigerator 1 is equipped with doors that open and close the openings of each storage compartment. These doors include a left and right rotating refrigerator compartment door 2a, 2b that opens and closes the opening of the refrigerator compartment 2, and a pull-out type ice maker compartment door 3a, upper freezer compartment door 4a, lower freezer compartment door 5a, and vegetable compartment door 6a that open and close the openings of the ice maker compartment 3, upper freezer compartment 4, lower freezer compartment 5, and vegetable compartment 6, respectively. The internal material of these multiple doors is mainly made of foamed urethane. In addition, each door is equipped with a sealing member (not shown) on the outer periphery of its inner surface.

[0019] The refrigerator compartment 2, the ice-making compartment 3, and the upper freezer compartment 4 are separated by an insulating partition wall 27, and the lower freezer compartment 5 and the vegetable compartment 6 are separated by an insulating partition wall 28. In addition, at the front edge between the ice-making compartment 3 and the upper freezer compartment 4, a partition portion 29 is provided at a position that contacts the sealing member on the inner right end of the ice-making compartment door 3a and the sealing member on the inner left end of the upper freezer compartment door 4a when the ice-making compartment door 3a and the upper freezer compartment door 4a are closed.

[0020] The front edge between the ice-making compartment 3 and the upper freezer compartment 4 and the lower freezer compartment 5 is provided with a partition portion 30 at a position where it contacts the sealing members on the lower inner surfaces of the ice-making compartment door 3a and the upper freezer compartment door 4a, and the sealing member on the upper inner surface of the lower freezer compartment door 5a, when the ice-making compartment door 3a, the upper freezer compartment door 4a, and the lower freezer compartment door 5a are closed.

[0021] Door hinges (not shown) for fixing the refrigerator 1 and doors 2a and 2b are provided on the front of the outer top surface of the insulated box body 10 and on the front edge of the insulated partition wall 27, and the upper door hinges provided on the outer top surface are covered with door hinge covers 16.

[0022] The ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5 are basically storage compartments where the interior is kept at a freezing temperature (below 0°C), for example, an average of about -18°C. The refrigerator compartment 2 is a storage compartment where the interior is kept at a refrigeration temperature (above 0°C), for example, an average of about 4°C. The vegetable compartment 6 is a storage compartment where the interior is kept at a refrigeration temperature (above 0°C), for example, an average of about 7°C. Hereinafter, in this specification, the ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5, which are storage compartments at freezing temperatures, will be collectively referred to as the freezer compartment 60.

[0023] Figure 2 is a vertical cross-sectional view of refrigerator 1 in Figure 1, and is a cross-sectional view AA of Figure 1. Figure 3 is a front view showing the internal configuration of refrigerator 1 in Figure 1, and is a front view of refrigerator 1 in Figure 1 with the door and containers removed. The configuration of refrigerator 1 will be explained with reference to Figures 2 and 3.

[0024] As shown in Figure 2, the refrigerator 1 is separated from the outside by an insulated box 10 formed by filling a foamed insulation material (foamed urethane in this embodiment) between a steel plate outer box 10a and a synthetic resin inner box 10b (for example, ABS resin). In addition to the foamed insulation material, a vacuum insulation material 25 with a lower thermal conductivity than the foamed insulation material is installed between the outer box 10a and the inner box 10b to suppress the reduction in internal volume and improve insulation performance. In this embodiment, the vacuum insulation material 25 is installed on the back, bottom, and both sides of the insulated box 10.

[0025] Furthermore, the insulation material inside the insulated partition wall 27 is expanded polystyrene, and the inside of the insulated partition wall 28 is filled with foamed urethane as insulation material. The foamed urethane inside the insulated partition wall 28 is filled together with the foamed urethane of the insulated box body 10 during the process of foaming and filling urethane between the outer box 10a and the inner box 10b of the insulated box body 10.

[0026] The refrigerator compartment doors 2a and 2b are equipped with multiple door pockets 33a, 33b, and 33c on the inside. The refrigerator compartment 2 is divided into multiple storage spaces by shelves 34a, 34b, 34c, and 34d. The ice maker door 3a, the upper freezer compartment door 4a, the lower freezer compartment door 5a, and the vegetable compartment door 6a are equipped with an ice maker container 3b, an upper freezer container 4b, a lower freezer container 5b, and a vegetable compartment container 6b, which can be pulled out as a single unit.

[0027] As shown in Figures 2 and 3, the refrigerator 1 has a cooler compartment 8 at the back of the lower freezer compartment 5, in which the first cooler 14 is housed, and a freezer fan 9a is provided at the top of the cooler compartment 8.

[0028] A partition wall 180 is provided between the freezer fan discharge air passage 195 downstream of the freezer fan 9a and the freezer air passage 100 through which cold air blown into the freezer 60 flows. The partition wall 180 has a first opening 180a. The first opening 180a is equipped with a freezer damper 170 as a means for adjusting the airflow (airflow adjustment means).

[0029] Furthermore, the partition wall 180 has a second opening 180b on its left side, which has a smaller opening area than the first opening 180a. The vegetable compartment air passage 132, which extends vertically from the left end of the freezer compartment 60, is connected to the second opening 180b, and a vegetable compartment damper 160 is provided at the bottom of the vegetable compartment air passage 132 as a means for adjusting the airflow (airflow adjustment means).

[0030] The freezer compartment air passage 100 is equipped with an ice-making compartment outlet (ice-making compartment discharge outlet) 101, an upper freezer compartment outlet (upper freezer compartment discharge outlet) 102, and a lower freezer compartment outlet (lower freezer compartment discharge outlet) 103, which blow cold air into the front ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5, respectively.

[0031] A freezer return air passage 104 is formed at the lower front of the cooler chamber 8, through which cold air returns from the ice-making chamber 3, the upper freezer chamber 4, and the lower freezer chamber 5. The freezer return air passage 104 is formed to have a width approximately equal to the width of the first cooler 14, so that cold air returns from the freezer chamber 60 to the first cooler 14 efficiently flows in.

[0032] Furthermore, a vegetable compartment air outlet 133 is provided at the outlet of the vegetable compartment air passage 132. A vegetable compartment return opening 136 is provided on the lower surface of the insulated partition wall 28 between the lower freezer compartment 5 and the vegetable compartment 6, and a vegetable compartment return air passage 135 is provided within the insulated partition wall 28, extending from the vegetable compartment return opening 136 to the lower front of the cooler compartment 8.

[0033] The rear of the refrigerator compartment 2 is equipped with a refrigerator compartment circulating air passage (hereinafter referred to as the first refrigerator compartment air passage) 110. The first refrigerator compartment air passage 110 is equipped with a refrigerator compartment outlet (refrigerator compartment discharge outlet) 111a that blows air into the space above the top shelf 34a, and a refrigerator compartment outlet (refrigerator compartment discharge outlet) 111b that blows air into the space between the top shelf 34a and the second shelf 34b from the top.

[0034] Refrigerator 1 is equipped with a second refrigerator compartment air passage 120 adjacent to the first refrigerator compartment air passage 110 (hereinafter referred to as the first refrigerator compartment air passage) 110, separated by a partition wall, behind the first refrigerator compartment air passage 110. A heat transfer plate (second cooler) 200 is formed in the partition wall between the first refrigerator compartment air passage 110 and the second refrigerator compartment air passage 120, and the first refrigerator compartment air passage 110 and the second refrigerator compartment air passage 120 are configured to exchange heat between the air in the first refrigerator compartment air passage 110 and the air in the second refrigerator compartment air passage 120.

[0035] Details of the first and second air passages 110 and 120 of the refrigerator compartment will be explained later. The opening area of ​​the refrigerator compartment outlet 111a is approximately 1000 mm². 2 The opening area of ​​the refrigerator compartment air outlet 111b is approximately 500 mm². 2 Therefore, the opening area of ​​the uppermost air outlet 111a is made larger than the opening area of ​​the lower air outlet 111b.

[0036] A first return port 115 for the refrigerator compartment is formed at the lower center of the first air passage 110 for the refrigerator compartment, which takes in air (cold air) from inside the refrigerator compartment 2. A second return port 131 for the refrigerator compartment is formed on the lower right side of the rear of the refrigerator compartment 2. A refrigerator compartment return air passage 130 is formed at the rear right end of the upper freezer compartment 4 and the lower freezer compartment 5, with one end communicating with the second return port 131 for the refrigerator compartment. The other end of the refrigerator compartment return air passage 130 is connected to the lower right side of the cooler compartment 8.

[0037] A vegetable compartment air passage 132 is formed from the lower left of the freezer compartment air passage 100 at the back of the ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5, extending downwards. A vegetable compartment outlet (vegetable compartment discharge port) 102a is formed at the outlet of the vegetable compartment air passage 132. A vegetable compartment return port 136 is opened on the lower surface of the insulating partition wall 28 between the lower freezer compartment 5 and the vegetable compartment 6, and a vegetable compartment return air passage 135, which is connected to the lower front of the cooler compartment 8, is formed inside the insulating partition wall 28.

[0038] A freezer return port 105 is formed at the lower front of the cooler chamber 8, through which cold air returns from the ice-making chamber 3, the upper freezer chamber 4, and the lower freezer chamber 5. The freezer return port 105 is formed to be approximately equal in width to the width of the first cooler 14, so that cold air returns from the ice-making chamber 3, the upper freezer chamber 4, and the lower freezer chamber 5 to flow into the first cooler 14 efficiently.

[0039] A refrigerator temperature sensor 41, a freezer temperature sensor 43, and a vegetable compartment temperature sensor 44 are provided on the rear side of the interior of the refrigerator compartment 2, the upper freezer compartment 4, and the vegetable compartment 6, respectively, and a cooler temperature sensor 40 is provided on the upper part of the first cooler 14. In this embodiment, the freezer temperature sensor 43 is provided in the upper freezer compartment 4, but it may also be provided in the lower freezer compartment 5.

[0040] These temperature sensors detect the temperatures of the refrigerator compartment 2, ice maker compartment 3, upper freezer compartment 4, lower freezer compartment 5, vegetable compartment 6, cooling compartment 8, and the first cooling unit 14. In addition, an outside air temperature sensor 37 and an outside air humidity sensor 38 are provided inside the door hinge cover 16 on the ceiling of the refrigerator 1 to detect the temperature and humidity of the outside air (air outside the refrigerator). Furthermore, door sensors (not shown) are provided to detect the open / closed state of doors 2a, 2b, 3a, 4a, 5a, and 6a, respectively.

[0041] A refrigerator fan 9a is installed at the bottom of the first refrigerator compartment air passage 110. A first refrigerator compartment damper 151 is provided at the inlet of the first refrigerator compartment air passage 110 as a means of blocking cold air. A second refrigerator compartment damper 152 is provided at the inlet of the second refrigerator compartment air passage 120 as a means of blocking cold air.

[0042] Furthermore, the second air passage 120 for the refrigerator compartment is provided as an air passage independent of the first air passage 110 for the refrigerator compartment. That is, the refrigerator 1 of this embodiment includes a second air passage 120 for the refrigerator compartment, which is provided as an air passage independent of the first air passage 110 for the refrigerator compartment and circulates the cold air that has exchanged heat with the first cooler 14 in the cooler compartment 8, and a second damper 152 for the refrigerator compartment that adjusts the airflow rate of the cold air flowing into the second air passage 120 for the refrigerator compartment.

[0043] The first refrigerator compartment damper 151 and the second refrigerator compartment damper 152 are driven by a single motor and are integrally formed. Hereinafter, the component that combines the functions of the first refrigerator compartment damper 151 and the second refrigerator compartment damper 152 will be referred to as the refrigerator compartment damper 150. In addition, a vegetable compartment damper 160 is provided in the vegetable compartment air passage 132 as a means of blocking cold air.

[0044] Figure 4 shows the configuration of the freezer compartment damper 170. The freezer compartment damper 170 includes a motor housing 170a and an opening 170b. The opening 170b is opened and closed by an opening / closing plate 170c. Specifically, a stepping motor (not shown) installed in the motor housing 170a can control the opening / closing plate 170c from a closed state with an opening angle of 0 degrees to a fully open state with an opening angle of 90 degrees, and it is also possible to set the opening / closing plate 170c to a semi-open state with an opening angle of 45 degrees.

[0045] A sealing member (not shown) is provided on the side of the opening / closing plate 170c facing the opening 170b, thereby preventing a gap from forming between the opening 170b and the opening / closing plate when it is closed.

[0046] Below the first cooler 14 in the cooler room 8, there is a defrost heater 21 that heats the first cooler 14. A gutter 23 is formed on the lower surface of the cooler room 8. A drain pipe 22 that communicates with the machine room 39 is provided downward from the lower end of the gutter 23. The machine room 39 is also equipped with a compressor 24 and an evaporation tray 32 positioned above the compressor 24.

[0047] The defrost heater 21 can be, for example, an electric heater of 50W to 200W, and in this embodiment, a 120W radiant heater is used. The defrost water generated during defrosting of the 11th cooler 14 is discharged from the gutter 23 through the drain pipe 22 to the evaporation tray 32 above the compressor 24, where it evaporates due to heat dissipation from the compressor 24 and ventilation by a machine room fan (not shown).

[0048] A container 36 is provided at the top of the insulated partition wall 27 inside the refrigerator compartment 2, and the interior temperature of the container 36 is maintained at approximately -1°C. The front of the container 36 can be opened and closed by a lid 36a. A gasket (not shown) is provided around the outer circumference of the lid 36a, and when the lid 36a is closed, the gasket causes the lid 36a and the container 36 to come into contact without any gaps, thus sealing the internal space of the container 36.

[0049] Furthermore, the back of the container 36 is equipped with a pump (not shown) that sucks air out of the container 36. When the lid 36a is closed, the air pressure inside the container 36 is reduced to approximately 0.8 atmospheres. As a result, the container 36 is no longer directly exposed to cold air blown in by the lid 36a, and a reduced-pressure environment is created, making it a storage space that suppresses drying and oxidation of food.

[0050] Figure 5 shows the vicinity of the second cooler according to the first embodiment, and is an exploded perspective view showing the air passage in the refrigerator compartment of the refrigerator 1. The heat transfer plate 200 constituting the second cooler has the function of separating the first air passage 110 and the second air passage 120 of the refrigerator compartment, and transferring cold heat from the air flowing through the second air passage 120 to the air flowing through the first air passage 110 of the refrigerator compartment.

[0051] As shown in Figure 5, the front of the first refrigerator compartment air passage 110, which is installed at the rear of the refrigerator compartment 2, is equipped with refrigerator compartment outlets 111a and 111b, and a heat transfer plate (second cooler) 200 is installed between the first refrigerator compartment air passage 110 and the second refrigerator compartment air passage 120 at the rear of the first refrigerator compartment air passage 110.

[0052] A partition member 121 is positioned inside the second air passage 120 of the refrigerator compartment. When the second damper 152 of the refrigerator compartment is open, as shown by the arrow in the figure, the airflow that flows upward through the left side 120a of the second air passage 120 of the refrigerator compartment reverses direction at the top of the second air passage 120 and flows downward through the right side 120b of the second air passage 120 of the refrigerator compartment.

[0053] In this embodiment of the refrigerator, the heat transfer plate (second cooler) 200 is made of aluminum. By using aluminum, which has high thermal conductivity, the cold air from the second air passage 120 of the refrigerator compartment is more easily transferred to the air in the first air passage 110 of the refrigerator compartment. Another embodiment is also conceivable in which resin (for example, polypropylene) is used for the heat transfer plate (second cooler) 200 to further reduce costs.

[0054] In other words, the heat transfer plate (second cooler) 200 only needs to perform the function of transferring the cold air from the second air passage 120 of the refrigerator compartment to the air in the first air passage 110 of the refrigerator compartment, and its material and shape are not limited. The heat transfer plate (second cooler) 200 is also equipped with a heat transfer plate temperature sensor 201.

[0055] Figure 6 is a schematic diagram showing the airflow path (air passage configuration) of the refrigerator 1 according to the first embodiment. The airflow inside the refrigerator will be explained using Figures 6, 2, and 3.

[0056] As shown in Figure 6, in refrigerator 1, when the freezer compartment damper 170 is open, the air in the cooling compartment 8 is pressurized by the freezer compartment fan 9a and sent from the freezer compartment fan discharge air passage 195 to the freezer compartment air passage 100. Regardless of the open / closed state of the refrigerator compartment first damper 151, the refrigerator compartment second damper 152, and the vegetable compartment damper 160, the air sent to the freezer compartment air passage 100 is blown out from the ice maker compartment outlet 101, the upper freezer compartment outlet 102, and the lower freezer compartment outlet 103 to the ice maker compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5, respectively.

[0057] The air from the ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5 passes through their respective storage compartments and returns to the cooler compartment 8 from the lower freezer compartment 5 via the freezer compartment return air passage 104. This airflow path from the cooler compartment 8 back to the cooler compartment 8 via the ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5 is called the freezer compartment airflow path.

[0058] When the first refrigerator compartment damper 151 is open and the freezer compartment fan 9a and the refrigerator compartment fan 9b are driven, the air in the condenser compartment 8, which has been pressurized by the freezer compartment fan 9a, is sent to the ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5. It also passes through the first refrigerator compartment damper 151, is pressurized again by the refrigerator compartment fan 9b, flows into the first refrigerator compartment air passage 110, and is sent to the refrigerator compartment 2 from the refrigerator compartment outlet 111. This airflow path from the condenser compartment 8 back to the condenser compartment 8 via the first refrigerator compartment air passage 110 is called the first refrigerator compartment airflow path.

[0059] When the refrigerator compartment's second damper 152 is open and the freezer compartment fan 9a is driven, the air pressurized by the freezer compartment fan 9a is sent to the ice-making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5. It also flows through the refrigerator compartment's second air passage 120, exchanges heat with the air in the refrigerator compartment's first air passage 110 at the heat transfer plate (second cooler) 200, flows through the refrigerator compartment's return air passage 130, and returns to the cooler compartment 8. This airflow path from the cooler compartment 8 back to the cooler compartment 8 via the refrigerator compartment's second air passage 120 is called the refrigerator compartment's second airflow path.

[0060] With the first refrigerator compartment damper 151 and the second refrigerator compartment damper 152 closed, driving the refrigerator compartment fan 9b causes air from inside the refrigerator compartment 2 to enter the first refrigerator compartment air passage 110 from the first refrigerator compartment return port 115, flow through the first refrigerator compartment air passage 110, and re-enter the refrigerator compartment 2 from the refrigerator compartment outlet 111, forming an airflow that circulates inside the refrigerator compartment 2. This airflow path that returns to the refrigerator compartment 2 from the refrigerator compartment 2 via the first refrigerator compartment air passage 100 is called the third refrigerator compartment airflow path.

[0061] When the vegetable compartment damper 160 is open and the freezer compartment fan 9a is driven, the air in the cooler compartment 8, which has been pressurized by the freezer compartment fan 9a, is sent to the ice making compartment 3, the upper freezer compartment 4, and the lower freezer compartment 5. At the downstream end of the freezer compartment air passage 100, it flows through the vegetable compartment air passage 132, which branches off from the freezer compartment air passage 100, and is blown out into the vegetable compartment 6 from the vegetable compartment outlet 131.

[0062] In the vegetable compartment 6, air is blown outwards towards the outside of the vegetable compartment container 6b, preventing the vegetables and other food stored in the container 6b from drying out. The air that has passed through the vegetable compartment 6 flows through the vegetable compartment return port 136 (see Figure 2) located on the lower surface of the insulating partition wall 28, through the vegetable compartment return air passage 135 (see Figure 2) provided inside the insulating partition wall 28, and returns to the cooler compartment 8. This airflow path from the cooler compartment 8 back to the cooler compartment 8 via the vegetable compartment 6 is called the vegetable compartment airflow path.

[0063] Figure 7 is a schematic diagram showing the configuration of the refrigeration cycle of a refrigerator according to the first embodiment.

[0064] The refrigerator 1 of this embodiment includes a compressor 24, an external heat radiator 50a as a means of releasing heat from the refrigerant, wall heat dissipation pipes 50b arranged on both sides of the insulated box body 10, condensation prevention pipes 50c arranged between the insulated partition walls 27, 28 and the front of the partition sections 29, 30 to suppress condensation, a capillary tube 53 as a means of reducing the pressure of the refrigerant, and a first cooler 14 that absorbs heat from inside the refrigerator by exchanging heat between the refrigerant and the air inside the refrigerator.

[0065] Furthermore, the wall-mounted heat dissipation pipe 50b is positioned on the inner surface of the outer box 10a in the area between the outer box 10a and the inner box 10b. In addition, the condensation prevention pipe 50c is positioned on the inner surfaces of the insulated partition walls 27, 28 and the partition sections 29, 30.

[0066] The refrigerator 1 also includes a dryer 51 to remove moisture in the refrigeration cycle and a gas-liquid separator 54 to suppress the inflow of liquid refrigerant into the compressor 24, and these are connected by refrigerant piping to constitute the refrigeration cycle. The refrigerant piping connecting the capillary tube 53, the first cooler 14, and the compressor 24 includes a heat exchange section 57 that performs heat exchange of the refrigerant.

[0067] In the refrigerator 1 of this embodiment, when the compressor 24 is driven, the refrigerant is compressed into a high-temperature, high-pressure gaseous refrigerant, which enters the external heat exchanger 50a. In the external heat exchanger 50a, heat is removed from the refrigerant by ventilation from an external fan (not shown), reducing its enthalpy, and it enters a two-phase state before flowing into the wall-surface heat dissipation piping 50b. In the wall-surface heat dissipation piping 50b, which is arranged on both sides of the insulated box 10, heat is mainly dissipated from the refrigerant to the outside air through the outer wall of the insulated box 10.

[0068] Next, refrigerant is introduced into the condensation prevention piping 50c, which is located in front of the insulated partition walls 27, 28 and partition sections 29, 30. Because insulated doors are provided in front of the insulated partition walls 27, 28 and partition sections 29, 30, in the condensation prevention piping 50c, the refrigerant is mainly cooled by the air inside the chamber, becoming a liquid refrigerant, which flows through the dryer 51 to remove moisture, and then reaches the capillary tube 53. As the refrigerant flows through the capillary tube 53, it is depressurized and becomes a low-temperature, low-pressure two-phase refrigerant before reaching the inlet of the first cooler 14.

[0069] The air returning from each storage compartment in the refrigerator is cooled to a low temperature by passing through the first cooler 14 driven by the freezer fan 9a, and then cools each storage compartment in the refrigerator again. At this time, the refrigerant absorbs heat from the air in the refrigerator, its enthalpy increases, its dryness increases, and it becomes a nearly saturated gaseous refrigerant before reaching the outlet of the first cooler 14.

[0070] A portion of the piping returning from the outlet of the first cooler 14 to the compressor 24 is positioned close to the capillary tube 53 to exchange heat, and is heated by the refrigerant in the capillary tube 53, causing its enthalpy to rise (its temperature to increase) before being drawn back into the compressor 24.

[0071] By providing the heat exchange section 57 in this manner, the temperature of the refrigerant drawn into the compressor rises, preventing condensation and frost formation on the refrigerant piping. Furthermore, the enthalpy of the refrigerant flowing into the first cooler 14 decreases due to heat exchange, improving the cooling capacity of the first cooler 14. The refrigerant used in the refrigeration cycle is isobutane, a flammable refrigerant.

[0072] Next, the cooling operation and defrosting operation of the refrigerator 1 of this embodiment will be described. As is well known, these operations are performed by the control device CNT shown in Figure 1. Figure 12 shows the main components that make up the control device CNT. In Figure 12, the control device CNT is equipped with a microcomputer as its main component.

[0073] The microcomputer includes a central processing unit (Pr) equipped with arithmetic functions, a non-volatile memory (Mc) that stores the program for operating the central processing unit (Pr), constants necessary for calculations, etc., a volatile memory (Md) that temporarily stores the calculation results of the calculation process and information necessary for the calculation process, an input circuit (Ic) for receiving detection signals from at least the refrigerator compartment temperature sensor 41, the freezer compartment temperature sensor 43, the vegetable compartment temperature sensor 44, the freezer compartment return port temperature sensor 45, the first refrigerator compartment return port temperature sensor 47, the lower refrigerator compartment temperature sensor 49, and the heat transfer plate temperature sensor 201, and an output circuit (Oc) for converting the control signals calculated by the central processing unit (Pr) into electrical signals and outputting them.

[0074] At least the first refrigerator compartment damper 151, the second refrigerator compartment damper 152, the vegetable compartment damper 160, and the freezer compartment damper 170 are connected to the output circuit (Oc), which performs cooling and defrosting operations. The central processing unit (Pr), the input circuit (Ic), and the output circuit (Oc) are connected by a bus line (Bs), which provides input signals to the central processing unit (Pr) and outputs control signals from the central processing unit (Pr).

[0075] The central processing unit (Pr) executes programs stored in non-volatile memory (Mc) to perform, for example, the cooling operation control shown in Figure 8, and the defrosting operation control shown in Figure 10. Next, the control flow for each operation will be explained.

[0076] First, during the cooling operation of refrigerator 1, the cold air that has exchanged heat with the first cooler 14 passes through each airflow path and cools each storage compartment.

[0077] Figure 8 is a flowchart showing the basic control of the cooling operation of refrigerator 1 in this embodiment. The reference numerals attached to each control block indicate the processing steps, and will be referred to as "Process S-○○" below. Referring to Figure 6 together with the flowchart described below will be helpful for understanding.

[0078] As shown in this figure, the freezer temperature T detected by the freezer temperature sensor 43 F is determined whether it is above the reference upper limit temperature T F_start or higher (for example, -18°C or higher), and also, the refrigerator temperature T detected by the refrigerator temperature sensor R is determined whether it is above the reference upper limit temperature T R_start or higher (for example, 4°C or higher) (step S-1).

[0079] “T F ≧T F_start ”, or “T R ≧T R_start ” If so, the compressor 24 and the freezer fan 9a are driven to start the basic cooling operation (step S-2). While the compressor 24 is driven, the first cooler 14 becomes low temperature, for example, -25°C or lower. Therefore, frosting occurs on the first cooler 14. In the basic cooling operation, the opening and closing of the damper are controlled by repeating from “step S-3” to “step S-19”.

[0080] After starting the basic cooling operation, it is determined whether T F is above T F_start (step S-3), and if “T F ≧T F_start ”, the freezer damper 170 is opened (step S-4).

[0081] Next, it is determined whether T R is above T R_start (step S-5), and if “T R ≧T R_start ”, it is determined whether the refrigerator temperature T R is above a predetermined temperature T R_high or higher (for example, 5°C or higher) (step S-R1). If “T R ≧T R_high ”, the first refrigerator damper 151 is opened and the refrigerator fan 9b is driven (step S-R2). Also, if “T R ≦T R_high ”, the second refrigerator damper 152 is opened and the refrigerator fan 9b is driven (step S-R3).

[0082] The temperature T of the vegetable compartment V is TV_off Determine if it is above (step S-6), and "T V ≧T V_off If this is the case, open the vegetable compartment damper 160 (step S-7).

[0083] By performing steps S-3 through S-7, and steps S-R1 through S-R3, the dampers corresponding to the storage rooms requiring cooling can be opened.

[0084] When the freezer compartment damper 170 is open, the cold air that has exchanged heat with the first cooler 14 is blown into the freezer compartment 60 via the freezer compartment airflow path to cool the freezer compartment 60. Also, when the refrigerator compartment first damper 151 is open, the cold air that has exchanged heat with the first cooler 14 is blown directly into the refrigerator compartment 2 via the refrigerator compartment first airflow path to cool the refrigerator compartment 2. This operation, in which the cold air that has exchanged heat with the first cooler 14 is blown directly into the refrigerator compartment 2 to cool it, is called "direct cooling operation".

[0085] When the second damper 152 of the refrigerator compartment is open, the cold air that has exchanged heat with the first cooler 14 cools the heat transfer plate (second cooler) 200 via the second airflow path of the refrigerator compartment. The air inside the refrigerator compartment 2 circulates within the refrigerator compartment via the third airflow path of the refrigerator compartment. The air inside the refrigerator compartment 2 is cooled by the heat exchange between the low-temperature heat transfer plate (second cooler) 200 and the relatively high-temperature air inside the refrigerator compartment 2. Hereinafter, this cooling operation of the refrigerator compartment 2 via the heat transfer plate (second cooler) 200 will be referred to as "indirect cooling operation".

[0086] When the vegetable compartment damper 160 is open, the cold air that has been heat-exchanged with the first cooler 14 is blown into the vegetable compartment 6 via the vegetable compartment airflow path to cool the vegetable compartment 6.

[0087] The above cooling process is completed when each damper is closed in steps S-8 through S-18.

[0088] Freezer room temperature T F is the standard lower limit temperature T F_off Determine if it is below (for example, below -22℃) (step S-8), and "T F≦T F_off If this is the case, close the freezer damper 170 (step S-9).

[0089] Refrigerator temperature T R is the standard lower limit temperature T R_off Determine if it is below (for example, 1°C or below) (step S-10), and "T R ≦T R_off If this is the case, the first refrigerator compartment damper 151 and the second refrigerator compartment damper 152 are closed and the refrigerator compartment fan 9b is stopped (step S-11).

[0090] After "Process S-11," the process proceeds to "Process S-12," which involves off-cycle operation. Since off-cycle operation is performed once every N cycles, "Process S-12" determines whether or not to perform it. In refrigerator 1 of this embodiment, N=2.

[0091] In off-cycle operation, both the first refrigerator compartment damper 151 and the second refrigerator compartment damper 152 are closed, and the refrigerator compartment fan 9b is driven (step S-13).

[0092] The heat transfer plate temperature T detected by the heat transfer plate temperature sensor 201 DR is the predetermined temperature T DR_off After the temperature exceeds (for example, 2°C or higher), or after the elapsed time Δt from the start of off-cycle operation has reached a predetermined time Δt DR_off After the above time (for example, 10 minutes or more) (step S-14), the refrigerator fan 9b is stopped and the off-cycle operation is terminated (step S-15). Also, the counter is reset after the off-cycle operation is terminated (step S-16).

[0093] Vegetable compartment temperature T V is the standard lower limit temperature T V_off Determine if it is below (for example, 12℃ or below) (step S-17), and "T V ≦T V_off If this is the case, close the vegetable compartment damper 160 (step S-18).

[0094] The process from "Step S-3" to "Step S-19" is repeated until all dampers are closed. After determining that all dampers are closed (Step S-19), the compressor 24 and the refrigeration fan 9a are stopped (Step S-20), and after adding 1 to the counter (Step S-21), the basic cooling operation is completed.

[0095] After the basic cooling operation is completed, it is determined whether the conditions for starting the defrosting operation, such as the cumulative time since the start of operation of the compressor 24 reaching a predetermined time, are met (step S-22). If the conditions for starting the defrosting operation are met, the defrosting operation described later is started (step S-23).

[0096] Figure 9 is a graph showing an example of temperature changes during the cooling operation of refrigerator 1 in this embodiment. The horizontal axis represents time, and the vertical axis represents the temperature of each part and the operating state of each component. On the horizontal axis of Figure 9, (1) t0 is the start time of the cooling operation. (2) t1 is the time when the vegetable compartment damper 160 is closed. (3) t2 is the time when the refrigerator compartment fan 9b is stopped, the freezer compartment damper 170 is opened, and the refrigerator compartment second damper 152 is closed. (4) t3 is the time when the freezer damper 170 is closed and the compressor 24 and the freezer fan 9a are stopped. (5) t4 is the time when the compressor 24, the freezer fan 9a, and the refrigerator fan 9b are driven and the second refrigerator damper 152 and the vegetable damper 160 are opened. (6) t5 is the time when the vegetable compartment damper 160 is closed. (7) t6 is the time when the freezer damper 170 is opened. (8) t7 is the time when the second damper 152 of the refrigerator compartment is closed and off-cycle operation is started. (9) t8 is the time when the freezer damper 170 is closed and the compressor 24 and the freezer fan 9a are stopped. (10) t9 is the time when the refrigerator fan 9b is stopped and the off-cycle operation ends. (11)t 10 This is the time when the compressor 24, the freezer fan 9a, and the refrigerator fan 9b are driven, and the refrigerator second damper 152 and the vegetable compartment damper 160 are opened. This indicates that.

[0097] At time t0, "T R ≧T R_start The compressor 24 and the refrigeration fan 9a are activated (process S-2), and the basic cooling operation begins. R ≧T R_start " and "T R ≦T R_high Therefore, the second damper 152 of the refrigerator compartment opens and the refrigerator compartment fan 9b is driven (process S-R3), further, "T V ≧T V_off Therefore, the vegetable compartment damper 160 opens (step S-7). As a result, the refrigerator compartment 2 is cooled by indirect cooling operation, and the vegetable compartment 6 is cooled by cold air being blown into the vegetable compartment airflow path.

[0098] At time t1, T V ≦T V_off As a result, the vegetable compartment damper 160 closes (step S-18), and the cooling of the vegetable compartment 6 stops.

[0099] At time t2, "T R ≦T R_off As a result, the second damper 152 of the refrigerator compartment closes, the refrigerator compartment fan 9b stops (process S-11), and the indirect cooling operation of refrigerator compartment 2 ends. Note that off-cycle operation is not performed because the counter = 1 and N≧2 is not satisfied. Also, "T F ≧T F_start This causes the freezer damper 170 to open (step S-4), and cold air is blown into the freezer airflow path, thereby cooling the freezer compartment 60.

[0100] At time t3, "T F ≦T F_off As a result, the freezer damper 170 closes (process S-9), and the cooling of the freezer 60 ends. With all dampers closed, the compressor 24 and the freezer fan 9a stop (process S-20), and the basic cooling operation ends.

[0101] At time t4, "T R ≧T R_startThe compressor 24 and the refrigeration fan 9a are activated (process S-2), and the basic cooling operation starts again. R ≧T R_start " and "T R ≦T R_high Therefore, the second damper 152 of the refrigerator compartment is opened and the refrigerator compartment fan 9b is driven (process S-R3) to perform indirect cooling operation. Furthermore, "T V ≧T V_off Therefore, the vegetable compartment damper 160 opens (process S-7), and cooling of the vegetable compartment 6 begins.

[0102] In indirect cooling operation, the refrigerator compartment 2 is highly humid (high absolute humidity), and the heat transfer plate (second cooler) 200 becomes cold (low saturation absolute humidity of the wall surface) in order to cool the refrigerator compartment 2. As a result, moisture from the air in the refrigerator compartment 2 adheres to the heat transfer plate (second cooler) 200, causing frost to form. However, since the heat transfer plate (second cooler) 200 is at a higher temperature (for example, -5°C) compared to the first cooler 14, frost formation can be suppressed compared to when cooling with the first cooler 14, and it is possible to maintain a highly humid state (high absolute humidity).

[0103] At time t5, "T V ≦T V_off As a result, the vegetable compartment damper 160 closes (process S-18), and the cooling of the vegetable compartment ends.

[0104] At time t6, "T F ≧T F_start This causes the freezer damper 170 to open (process S-4), and the cooling of the freezer 60 begins.

[0105] At time t7, "T R ≦T R_off As a result, the second damper 152 in the refrigerator compartment closes and the refrigerator compartment fan 9b stops (step S-11). However, since the counter becomes 2 and N≧2 is satisfied, the refrigerator compartment fan 9b starts running again (step S-13).

[0106] In off-cycle operation, the temperature rise in refrigerator compartment 2 is suppressed by exchanging heat between the heat transfer plate (second cooler) 200, which has become cold during the cooling of refrigerator compartment 2, and the air inside refrigerator compartment 2 flowing through the third air supply path of refrigerator compartment 2.

[0107] Furthermore, the moisture content in the refrigerator compartment 2 can be increased by evaporating the condensation or frost that forms on the heat transfer plate (second cooler) 200 during cooling into the air inside the refrigerator compartment 2. This operation prevents a rapid rise in temperature in the refrigerator compartment and also creates a refrigerator compartment 2 with high humidity, thereby suppressing food spoilage.

[0108] Off-cycle operation has a certain effect as a defrosting mechanism because it allows heat exchange between the relatively high-temperature air in the refrigerator compartment 2 and the heat transfer plate (second cooler) 200. However, if the main purpose is to prevent temperature rise and increase humidity in the refrigerator compartment 2, it is not necessary to completely melt the frost on the heat transfer plate (second cooler) 200. In this case, however, a more reliable defrosting method for the heat transfer plate (second cooler) 200 is required.

[0109] At time t8, "T F ≦T F_off This causes the freezer damper 170 to close (process S-9), and the cooling of the freezer 60 is completed.

[0110] At time t9, "T DR ≧T DR_off This signals the end of the off-cycle operation and the refrigerator fan 9b stops (process S-15).

[0111] time t 10 So, just like t0, "T R ≧T R_start Then the compressor 24 and the refrigeration fan 9a are activated (process S-2), and the basic cooling operation starts again.

[0112] The above is a description of one example of the cooling operation of the refrigerator 1 of this embodiment, and is not necessarily limited to the above operation.

[0113] Next, the defrost operation of the refrigerator 1 of the present embodiment will be described. FIG. 10 is a flowchart showing the basic control of the defrost operation of the refrigerator 1 of the present embodiment.

[0114] There are a plurality of start conditions for the defrost operation of the refrigerator 1 of the present embodiment. During the cooling operation in FIG. 8, for example, when the integrated time from the start of the operation of the compressor 24 reaches a predetermined value and it is determined that the defrost operation should start (Yes determination in step S-22), the defrost operation shown in FIG. 10 is started.

[0115] After starting the defrost operation, a pre-cooling operation for cooling the freezer compartment 60 to a lower temperature than normal is started (step S2-1). The pre-cooling operation is performed for a predetermined time Δt d1 (for example, 30 minutes) elapses, or when the freezer compartment temperature T F reaches the pre-cooling operation end temperature T F_off lower than the normal predetermined temperature T F_off2 (for example, -24°C or lower), the operation ends (step S2-2), the compressor 24 is stopped, and power is supplied to the freezer compartment fan 9a and the defrost heater 21 (step S2-3).

[0116] After starting the power supply to the defrost heater 21, the damper and the fan are controlled by repeating "step S2-4" to "step S2-9".

[0117] After starting the power supply to the defrost heater 21, it is determined whether the cooler temperature T DF is lower than the heat transfer plate defrost end temperature T DR2_off which is a predetermined temperature sufficiently higher than 0°C, the melting temperature (step S2-4). If "T DF ≦T DR2_off ", the refrigerator compartment first damper 151 is closed, the refrigerator compartment second damper 152 is opened, and the refrigerator compartment fan 9b is driven (step S2-5).

[0118] Next, it is determined whether the cooler temperature T DF is lower than the defrost temperature T DR1_off using the first air supply path which is a predetermined temperature lower than T DF_off (for example, 1°C or lower) (step S2-6). If "T DF ≦T DR1_offIf it is "」, open the first refrigerator damper 151, close the second refrigerator damper 152, and drive the refrigerator fan 9b (step S2-7).

[0119] Heat transfer plate temperature T DR is T DR2_off Determine whether it is greater than or equal to T (step S2-8), and if it is "T DR ≧T DR2_off ", close the first refrigerator damper 151 and the second refrigerator damper 152, and stop the freezer fan 9a and the refrigerator fan 9b (step S2-9).

[0120] Repeat the above operations until the cooler temperature T DF is greater than or equal to the cooler defrost end temperature T DF_off and the heat transfer plate temperature T DR is greater than or equal to the heat transfer plate defrost end temperature T DR2_off (step S2-10).

[0121] By repeating these "steps S2-4" to "steps S2-10", the air heated by the defrost heater 21 can be sent to the appropriate air supply paths 110 and 120 according to the air temperature, and the defrosting of the heat transfer plate (the second cooler) 200 can be performed.

[0122] After making a Yes determination in "step S2-10", stop the defrost heater 21 (step S2-11). Subsequently, after stopping the defrost heater 21, after the drainage time Δt d2 (for example, 3 minutes) has elapsed (step S2-12), end the defrost operation.

[0123] FIG. 11 is a graph showing an example of temperature changes during the defrost operation of the refrigerator 1 of the present embodiment. On the horizontal axis of this figure, (1) t d0 is the start time of the pre-cooling operation, (2) t d1 is the time when the freezer temperature T F reaches the lower limit temperature of T F_off , (3) t d2 is the time when the cooler temperature T DF is the heat transfer plate defrost end temperature T by the first refrigerator air supply pathDR1_off The time to reach (4)t d3 The heat transfer plate temperature T DR is the heat exchanger plate defrosting end temperature T DR2_off At the time it becomes, (5)t d4 is the cooler temperature T DF is the cooler defrosting end temperature T DF_off At the time it becomes, (6)t d5 After the defrosting operation is completed, the drainage time Δt d2 elapsed time This indicates that.

[0124] time t d0 Then, the start of defrosting operation is determined, and pre-cooling operation begins (step S2-1). During pre-cooling operation, the compressor 24 and the freezer fan 9a are driven, and the freezer compartment 60 is cooled, so the temperature of the freezer compartment 60 decreases.

[0125] time t d1 So, T F ≦T F_off2 The determination is made (step S2-2), the pre-cooling operation ends, the compressor 24 stops, the refrigeration chamber damper 170 closes, and the defrost heater 21 is driven (step S2-3). Also, at the same time T DF ≦T DR1_off Therefore, the first damper 151 of the refrigerator compartment opens, and the refrigerator compartment fan 9b is driven (step S2-7).

[0126] As a result, the air heated by the defrost heater 21 is blown to the heat transfer plate (second cooler) 200 via the first airflow path of the refrigerator compartment. The first cooler 14 is heated by the defrost heater 21, and as the temperature gradually rises, the frost attached to the first cooler 14 melts when it reaches the melting temperature (0°C).

[0127] If the temperature of the first cooler 14 is lower than the temperature of the heat transfer plate (second cooler) 200, the temperature of the heat transfer plate (second cooler) 200 decreases. If the temperature of the first cooler 14 is higher than the temperature of the heat transfer plate (second cooler) 200, the temperature of the heat transfer plate (second cooler) 200 increases, and when it reaches its melting temperature (0°C), the frost attached to the heat transfer plate (second cooler) 200 melts. The heat applied to the first cooler 14 and the heat transfer plate (second cooler) 200 is used to melt the frost, so the temperature of the first cooler 14 and the heat transfer plate (second cooler) 200 remains constant at 0°C until the frost has completely melted.

[0128] Furthermore, at the start of defrosting, the temperature of the first cooler 14 is sufficiently lower than the temperature of the air inside the refrigerator compartment 2. Therefore, the air heated by the defrost heater 21 is cooled again by the first cooler 14 and blown into the refrigerator compartment 2, thereby maintaining or lowering the air temperature in the refrigerator compartment 2.

[0129] time t d2 So, "T DF ≧T DR1_off " and "T DF ≦T DR2_off As a result, the first damper 151 in the refrigerator compartment is closed (process S2-5).

[0130] As a result, the air heated by the defrost heater 21 is blown to the heat transfer plate (second cooler) 200 via the second airflow path of the refrigerator compartment. At this time, the temperature of the first cooler 14 has risen sufficiently, and the air heated by the defrost heater 21 remains at a high temperature even after passing through the first cooler 14. By blowing this high-temperature air to the heat transfer plate (second cooler) 200 via the second airflow path of the refrigerator compartment, the temperature of the heat transfer plate (second cooler) 200 rises.

[0131] Furthermore, at this time, the temperature of the heat transfer plate (second cooler) 200 can be increased without blowing high-temperature air into the refrigerator compartment 2, thereby suppressing an excessive rise in the temperature of the refrigerator compartment 2.

[0132] time t d3 So, "T DR ≧T DR2_offTherefore, it is determined that the defrosting of the heat transfer plate (second cooler) 200 is complete, and the second damper 152 of the refrigerator compartment is closed, and the freezer compartment fan 9a and the refrigerator compartment fan 9b are stopped (step S2-9). As a result, the defrost heater 21 heats only the first cooler 14.

[0133] time t d4 So, "T DR ≧T DR2_off " and "T DF ≧T DF_off Therefore, the defrost heater 21 is stopped (step S2-11).

[0134] time t d5 Then, after the defrost heater 21 has finished, the drainage time Δt d2 After the specified time has elapsed, the defrosting operation will be terminated.

[0135] Having described the configuration of the refrigerator 1 of this embodiment, the effects of the refrigerator 1 of this embodiment will now be explained.

[0136] The refrigerator 1 of this embodiment is equipped with a first cooling unit, which is a first cooler 14; a defrost heater 21, which is a heat-generating unit that heats at least the first cooling unit; a first air passage 110 or a second air passage 120 for the refrigerator compartment, through which air from the cooler compartment 8 housing the first cooler 14 flows; and a heat transfer plate 200, which is a second cooling unit, arranged in the region through which air that has passed through the first air passage 110 or the second air passage 120 flows.

[0137] During cooling operation, the heat transfer plate (second cooler) 200 is cooled to below the dew point or frost point of the air in the refrigerator compartment 2, causing condensation or frost to form on the heat transfer plate (second cooler) 200. To eliminate the condensation or frost on the heat transfer plate (second cooler) 200, when the defrost heater 21 is energized, heated air from the cooler compartment 8 is blown to the heat transfer plate (second cooler) 200 via an air passage (in this embodiment, the first air passage 110 of the refrigerator compartment or the second air passage 120 of the refrigerator compartment).

[0138] As a result, reliable defrosting of the heat transfer plate (second cooler) 200 is achieved without providing a dedicated heater for the second cooling section, making the refrigerator 1 of this embodiment a more reliable refrigerator.

[0139] In the refrigerator 1 of this embodiment, a freezer damper 170, which is an airflow resistance adjusting means, is provided between the freezer fan discharge air passage 195, which is located downstream of the freezer fan 9a, and the freezer air passage 100, through which cold air blown into the freezer 60 flows.

[0140] By closing the freezer compartment damper 170, it is possible to prevent the air heated by the defrost heater 21 from flowing into the freezer compartment 60 when the defrost heater 21 is powered on. This suppresses the temperature rise of the freezer compartment 60 during defrosting operation, and the refrigerator 1 of this embodiment is a refrigerator that can suppress food deterioration in the freezer compartment 60.

[0141] Furthermore, in the refrigerator 1 of this embodiment, the heat transfer plate (second cooler) 200 is equipped with a heat transfer plate temperature sensor 201, and when the temperature detected by the heat transfer plate temperature sensor 201 reaches a predetermined temperature of 0 degrees or higher, which is the frost melting temperature, the freezer fan 9a is stopped.

[0142] This allows for reliable detection of frost removal, providing a more reliable refrigerator. Furthermore, it suppresses unnecessary temperature increases of the heat transfer plate (second cooler) 200, making the refrigerator 1 of this embodiment a refrigerator that can suppress food deterioration due to temperature rise inside the refrigerator compartment.

[0143] In the refrigerator 1 of this embodiment, the first air passage 110 of the refrigerator compartment is equipped with a heat transfer plate (second cooler) 200 on one side of the air passage and is an air passage that communicates with the cooler compartment 8 and the refrigerator compartment 2. During defrosting operation, the air is humidified by the frost and melted water moisture on the first cooler 14 and becomes highly humid (high absolute humidity) air, which can then be sent into the refrigerator compartment 2. This allows for defrosting of the heat transfer plate (second cooler) 200 and increases the humidity inside the refrigerator compartment 2, making the refrigerator 1 of this embodiment a refrigerator that can suppress food deterioration inside the refrigerator compartment 2.

[0144] In the refrigerator 1 of this embodiment, the second air passage 120 of the refrigerator compartment is equipped with a heat transfer plate (second cooler) 200 on the air passage, communicates with the cooler compartment 8, and does not communicate with the refrigerator compartment 2. This allows air heated to a high temperature by the defrost heater 21 during defrosting operation to be sent to the heat transfer plate (second cooler) 200 without being sent into the refrigerator compartment 2.

[0145] This allows the heat transfer plate (second cooler) 200 to be defrosted without unnecessarily raising the temperature inside the refrigerator compartment 2. As a result, the refrigerator 1 of this embodiment is a refrigerator that can defrost the heat transfer plate (second cooler) 200 more reliably and can suppress food deterioration inside the refrigerator compartment 2.

[0146] Furthermore, the refrigerator 1 of this embodiment includes a first refrigerator compartment air passage 110 which is an air passage that communicates with a cooling compartment 8 and a refrigerator compartment 2, and a second refrigerator compartment air passage 120 which is an air passage that communicates with the cooling compartment 8 and does not communicate with the refrigerator compartment 2, and a first refrigerator compartment damper 151 and a second refrigerator compartment damper 152 are provided in each air passage. Moreover, by switching the open and closed states of these two dampers during defrosting operation, it is possible to obtain both the effect of increasing the humidity inside the refrigerator compartment 2 and the effect of suppressing unnecessary temperature rises inside the refrigerator compartment 2.

[0147] Specifically, the temperature of the first cooler 14 is sufficiently lower than the temperature inside the refrigerator. DR1_off If the temperature is lower, opening the first refrigerator compartment damper 151 and closing the second refrigerator compartment damper 152 allows air from the cooling unit 8, which is humid and cooler than the temperature of the refrigerator compartment 2, to be blown into the refrigerator compartment through the first refrigerator compartment air passage 110, thereby increasing the humidity of the refrigerator compartment 2.

[0148] Furthermore, the temperature of the first cooler 14 rises, and the temperature of the first cooler 14 reaches T DR1_offIf the temperature is higher, closing the first refrigerator compartment damper 151 and opening the second refrigerator compartment damper 152 allows air to be blown to the heat transfer plate (second cooler) 200 without blowing relatively hot air into the refrigerator compartment 2, thereby enabling more reliable defrosting of the heat transfer plate (second cooler) 200 without unnecessarily raising the temperature of the refrigerator compartment 2.

[0149] As a result, the refrigerator 1 of this embodiment can increase the humidity of the refrigerator compartment 2 to suppress food deterioration, and can also reliably defrost the heat transfer plate (second cooler) 200 without unnecessarily raising the temperature of the refrigerator compartment 2.

[0150] In the above-described embodiment, the first refrigerator compartment air passage 110, the second refrigerator compartment air passage 120, and the heat transfer plate (second cooler) 200 are located on the rear of the refrigerator compartment 2. However, it is also possible to provide a similar configuration of the first vegetable compartment air passage, the second vegetable compartment air passage, and the heat transfer plate (second cooler) on the rear of the vegetable compartment 6.

[0151] The above embodiments are described in detail for the purpose of clearly illustrating the present invention and are not necessarily limited to those having all the configurations described. Furthermore, it is possible to replace some of the configurations of each embodiment with those of other embodiments. It is also possible to appropriately add configurations from other embodiments to the configuration of one embodiment. It is also possible to add, delete, or replace some of the configurations of this embodiment with those of other embodiments. In addition, the mechanisms and configurations described are those that are considered necessary and do not necessarily represent all of the mechanisms and configurations shown in the product. [Explanation of Symbols]

[0152] 1...Refrigerator, 2...Refrigerator compartment, 3...Ice maker compartment, 4...Upper freezer compartment, 5...Lower freezer compartment, 6...Vegetable compartment, 8...Cooler compartment, 9a...Freezer fan, 9b...Refrigerator fan, 10...Insulated box, 10a...Outer box, 10b...Inner box, 14...Cooler, 24...Compressor, 25...Vacuum insulation material, 27, 28...Insulated partition wall, 29, 30...Partition section, 39...Machine room, 41...Refrigerator temperature sensor, 43...Freezer temperature sensor, 44...Vegetable compartment temperature sensor, 45...Freezer return port temperature sensor, 47...Refrigerator first return port temperature sensor, 49... In the lower refrigerator compartment temperature sensor configuration, 60...freezer compartment, 100...freezer compartment air passage, 104...freezer compartment return air passage, 105...freezer compartment return port, 110...refrigerator compartment first air passage, 111...refrigerator compartment discharge port, 115...refrigerator compartment first return port, 120...refrigerator compartment second air passage, 130...refrigerator compartment return air passage, 131...refrigerator compartment second return port, 151...refrigerator compartment first damper, 152...refrigerator compartment second damper, 160...vegetable compartment damper, 170...freezer compartment damper, 195...freezer compartment fan discharge air passage, 200...heat transfer plate, 201...heat transfer plate temperature sensor.

Claims

1. First cooling unit and At least a heating element that heats the first cooling element, A fan that pressurizes the air cooled in the first cooling unit, A passage through which the air pressurized by the aforementioned fan flows, A second cooling unit is provided in the air passage or in the region through which the air passing through the air passage flows. The system comprises a refrigerator chamber containing the air that the second cooling unit cools, The second cooling unit cools the air in the refrigerator to a temperature below the dew point or frost point of the air. The system includes a control means that, while frost or condensation has formed on the second cooling section, generates heat in the heating section and drives the fan to blow the air heated by the heating section toward the second cooling section. The first cooling unit contains a freezer chamber that is in a freezing temperature zone and contains air to be cooled, The system includes means for adjusting the airflow resistance of the refrigeration temperature range, which reduces the amount of air flowing from the fan towards the freezer compartment and increases the amount of air flowing from the fan into the air passage. The aforementioned air passage is composed of a plurality of air passages, including a communicating air passage that communicates with the refrigerator compartment and a non-communicating air passage that does not communicate with the refrigerator compartment. The system includes a first damper that controls the flow of air to the connecting air passage and a second damper that controls the flow of air to the non-connecting air passage. A refrigerator characterized by the following features.

2. In the refrigerator according to Claim 1, The second cooling section is equipped with a second cooling section temperature sensor, The control means stops the fan and stops the airflow of the heat-generating air to the second cooling unit when the temperature detected by the second cooling unit temperature sensor exceeds a predetermined temperature. A refrigerator characterized by the following features.

3. In the refrigerator according to Claim 1, The air heated by the heat-generating section is blown towards the second cooling section via the connecting air passage. A refrigerator characterized by the following features.

4. In the refrigerator according to Claim 1, The air heated by the heat-generating section is blown towards the second cooling section via the non-communicating air passage. A refrigerator characterized by the following features.

5. In the refrigerator according to Claim 1, The communicating air passage and the non-communicating air passage are provided adjacent to each other, and a heat transfer plate with good heat transfer properties, which forms the second cooling section, is placed between the communicating air passage and the non-communicating air passage, so that cooling energy is transferred from the air flowing through the non-communicating air passage to the air flowing through the communicating air passage. A refrigerator characterized by the following features.

6. In the refrigerator according to claim 5, The system includes a first cooling section temperature sensor located in the first cooling section, The control means is When the heat-generating section is heated and the fan is driven, and the temperature detected by the first cooling section temperature sensor falls below a predetermined temperature, the first damper is opened, and the air heated by the heat-generating section is blown to the heat transfer plate via the communication air passage. When the temperature detected by the first cooling unit temperature sensor exceeds a predetermined temperature, the second damper is opened, and the air heated by the heating unit is blown to the heat transfer plate via the non-communicating air passage. A refrigerator characterized by the following features.

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