JP7723936B2 - household refrigerator - Google Patents

Description

An embodiment of the present invention relates to a household refrigerator.

Generally, it is best to store food at low temperatures to maintain its quality. However, some foods, such as fruits and vegetables like bananas, cucumbers, and eggplants, can suffer damage (chilling injury) such as discoloration or denting of the skin when exposed to low temperatures, and so keeping them cold alone may not be enough to maintain their freshness.

Patent Document 1 below discloses a refrigerator equipped with a vegetable compartment for storing fruits and vegetables and a temperature control means for controlling the temperature inside the vegetable compartment, with the temperature control means controlling the temperature inside the vegetable compartment depending on the growing season of the fruits and vegetables stored therein. The refrigerator in Patent Document 1 below aims to increase or maintain the sweet components in fruits and vegetables, and does not take into consideration low-temperature damage that can occur to food.

JP 2009-198097 A

The objective of this invention is to provide a household refrigerator that can store food while preventing chilling damage and maintaining its quality.

In one embodiment, the household refrigerator includes a storage compartment, a temperature adjustment means for adjusting the temperature of food stored in the storage compartment, and a control unit for controlling the temperature adjustment means. The control unit executes a cooled preservation operation for cooling the food to a first temperature and a recovery operation for heating the food to a second temperature higher than the first temperature to recover from low-temperature damage caused to the food. The control unit alternates between the cooled preservation operation and the recovery operation at a temperature where the first temperature is above the freezing temperature of the food and below a critical temperature, the second temperature is higher than the critical temperature, the temperature difference between the second temperature and the critical temperature is smaller than the temperature difference between the first temperature and the critical temperature, and the temperature is above 0°C .

Cross-sectional view of a home refrigerator according to one embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of a main part of the household refrigerator shown in FIG. A block diagram showing the electrical configuration of the household refrigerator of FIG.

Embodiments will be described with reference to the drawings. The following embodiments are illustrative, and the scope of the invention is not limited thereto. The following embodiments can be implemented in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. The following embodiments and their variations are within the scope of the invention set forth in the claims and their equivalents.

In the following description, left-right, front-back, and up-down refer to the directions when viewing the refrigerator from the front, and left-right corresponds to the width of the refrigerator. Furthermore, unless otherwise specified, right, left, top, bottom, front, rear, back, spine, and near side refer to the position or side when viewing the refrigerator from the front, and for the refrigerator doors, refer to the position or side when viewing the refrigerator from the front with the doors closed.

(1) Configuration of household refrigerator 1 As shown in Fig. 1, a household refrigerator 1 according to this embodiment (hereinafter sometimes referred to as refrigerator 1) includes a refrigerator main body 2 made of an insulated box with an opening at the front. The refrigerator main body 2 is configured by providing an insulating material such as vacuum insulation or foam insulation in an insulating space formed between an outer box made of steel plate and an inner box made of synthetic resin. The refrigerator main body 2 has multiple storage spaces inside the inner box, and the storage spaces are divided into upper and lower sections by an insulating partition wall 3.

The space above the insulating partition wall 3 is a refrigerated space that is cooled to a refrigeration temperature range (e.g., 1 to 5°C). The refrigerated space defined above the insulating partition wall 3 is further divided into upper and lower sections by a partition plate 4, with a refrigerator compartment 10 located above the partition plate 4 and a vegetable compartment 11 located below the partition plate 4.

The refrigerator compartment 10 is provided with multiple storage shelves 5. Below the lowest storage shelf 5 is a chilled compartment that is maintained at an especially low temperature within the refrigerator compartment 10. A hinged, pivotable refrigerator compartment door 15 is provided at the front opening of the refrigerator compartment 10. An operation display unit 6 is provided on the front of the refrigerator compartment door 15 to receive settings for the refrigerator 1 from the user and display the setting status of the refrigerator 1.

A refrigerator temperature sensor 60 for measuring the temperature inside the refrigerator compartment 10 is provided on the back of the refrigerator compartment 10. In addition, a door sensor 61 for detecting the opening and closing of the refrigerator compartment door 15 is provided around the periphery of the front opening of the refrigerator compartment 10.

The front opening of the vegetable compartment 11 is closed by a drawer-type vegetable compartment door 16. A pair of left and right support frames that hold the storage container 20 are fixed to the inside of the vegetable compartment door 16, and the storage container 20 is configured to be pulled out of the compartment when the door is opened. The specific configuration of the storage container 20 will be described in detail later.

The space below the insulating partition wall 3 is a freezer space that is cooled to a freezing temperature range (for example, -17°C or below). The freezer space is equipped with an ice-making compartment (not shown) equipped with an automatic ice maker and a first freezer compartment 13, which are located on either side of each other, with a second freezer compartment 14 located below them via a partition plate 7.

The openings of the ice-making compartment, first freezer compartment 13, and second freezer compartment 14 are closed by drawer-type doors 18, 19, similar to the vegetable compartment 11. Storage containers 21, 22 are held in a pair of left and right support frames fixed to the backside of each door 18, 19, and are configured so that the storage containers 21, 22 are pulled out of the compartment when the doors are opened. A freezer temperature sensor 62 is provided on the back of the second freezer compartment 14 to measure the temperature inside the second freezer compartment 14.

Behind the refrigeration temperature storage compartments (refrigerator compartment 10 and vegetable compartment 12), there is a refrigeration cooler compartment 33 that houses a refrigeration cooler 30, a refrigeration blower 31, and a drain pan 32. The refrigeration cooler 30 cools the air in the refrigeration cooler compartment 33 to generate cold air, which is then supplied to the refrigerator compartment 10 and vegetable compartment 11 via duct 34 by the refrigeration blower 31, thereby cooling the food stored in the vegetable compartment 10 and vegetable compartment 11. In other words, the refrigeration cooler 30 functions as a cooling unit that cools the food stored in the refrigerator compartment 10 and the food stored in the storage container 20 of the vegetable compartment 11.

The drain pan 32 receives condensation water (defrost water) generated from the refrigeration cooler 30 during defrosting operation. The condensation water accumulated in the drain pan 32 is drained via a drain hose (not shown) into an evaporation tray 37 located in the machine compartment 36 located at the bottom of the rear of the refrigerator main body 2.

At the back of the freezing temperature storage compartments (ice making compartment, first freezer compartment 13, and second freezer compartment 14), a freezer cooler compartment 42 is defined, housing a freezer cooler 38, a freezer blower 39, a defrost heating unit 40, and a drainage gutter 41. The freezer cooler 38 cools the air in the freezer cooler compartment 42 to generate cold air, which is then supplied by the freezer blower 39 via a duct 43 to the freezing temperature storage compartments, first freezer compartment 13, and second freezer compartment 14. Adjustable dampers may be provided at the outlets through which cold air is blown into the ice making compartment and first freezer compartment 13, allowing the ice making compartment and first freezer compartment 13 to be temperature controlled independently of the second freezer compartment 14.

The refrigerated cooler 30 and the freezer cooler 38, together with the compressor 44, condenser (not shown), and switching valve 46 (see Figure 3) housed in the machine compartment 36, constitute a refrigeration cycle. In the refrigeration cycle, refrigerant discharged from the compressor 44 is supplied to one of the refrigerated cooler 30 and the freezer cooler 38 by the switching valve 46. This causes one of the refrigerated coolers 30 and the freezer cooler 38 to which the refrigerant is supplied to be cooled to a predetermined temperature.

In addition, a control unit 45 consisting of a control board equipped with a microcomputer and other components that control the refrigerator 1 is provided on the outside of the refrigerator main body 2 (outside the refrigerator), for example, on the rear upper surface of the ceiling wall of the refrigerator main body 2.

(2) Configuration of storage container 20 As shown in Figure 2, the storage container 20 provided in the vegetable compartment 12 is a resin molded body and includes a lower container 23 provided across almost the entire width of the vegetable compartment 12 and an upper container 50 provided above the lower container 23.

The lower container 23 is box-shaped with a bottom that opens upward and is surrounded by a front wall, a rear wall, and left and right side walls. The lower container 23 has a deeper storage depth than the upper container 50. The interior of the lower container 23 is divided into front and rear sections by a front-to-rear partition wall 27 that extends in the width direction. This front-to-rear partition wall 27 is arranged to connect the inner surfaces of the left and right side walls of the lower container 23, with the lower front container 23a formed in front of the front-to-rear partition wall 27 and the lower rear container 23b formed behind it.

The lower container 23 is held by a pair of left and right support frames 24 fixed to the back side of the vegetable compartment door 16, and is configured to be pulled out when the vegetable compartment door 16 is opened. The upper ends of the left and right side walls of the lower container 23 form sliding surfaces 28 on which the container lower legs 53 provided on the upper container 50 rest and slide in the front-to-rear direction.

The front side of the upper opening of the lower rear container 23b is covered by the upper container 50 when the vegetable compartment door 16 is closed (when the storage container 20 is stored in the vegetable compartment 11) as shown in Figures 1 and 2. The rear side of the upper opening of the lower rear container 23b is covered by the sheet storage case 102 that stores the functional sheet 100.

The functional sheet 100 comprises a moisture-permeable sheet and a breathable sheet, and is provided inside the sheet storage case 102. The moisture-permeable sheet is a waterproof and breathable sheet material, for example, a porous sheet material with numerous pores with diameters of 0.5 μm to 3 μm. It allows water vapor particles and oxygen molecules to pass through but blocks water particles larger than the pores. Because it is porous, it also has a certain degree of windproofing properties that restrict the flow of air (wind). One example of a moisture-permeable sheet is a moisture-permeable waterproof sheet made by laminating polyester long-fiber nonwoven fabric and polyethylene porous film. The breathable sheet is made of a breathable sheet material, such as a nonwoven fabric sheet, a woven fabric, or a flexible porous resin sheet.

The upper container 50, located above the lower container 23, is box-shaped with a bottom and an upward opening, surrounded by a front wall, a rear wall, and left and right side walls. The top opening 51 on the top surface of the upper container 50 is an opening for loading and unloading stored items inside, and is closed by a lid 80 that can be opened and closed. The internal space of the upper container 50 forms a fruit and vegetable storage compartment separated from the vegetable compartment 11, and the bottom surface 50a of the upper container 50 serves as a storage area for placing food.

The upper container 50 is positioned adjacent to and below the partition plate 4 that separates the refrigerator compartment 10 and vegetable compartment 12. It is located in the vegetable compartment 12 and can be pulled out independently of the lower container 23 by sliding back and forth between inner box rails 25 provided on the left and right inner wall surfaces of the vegetable compartment 12 and sliding surfaces 28 provided on the upper ends of the left and right side walls of the lower container 23.

On the outside of the left and right side walls of the upper container 50, upper container legs 52 rest on the inner box rails 25 and slide forward and backward on them, while lower container legs 53 rest on the sliding surfaces 28 provided on the lower container 23 and slide forward and backward on them, protruding outward in the width direction. The upper container legs 52 and lower container legs 53 support the upper container 50 so that it can move forward and backward.

A downward-projecting protrusion 55 is provided at the front end of the bottom wall of the upper container 50. When the vegetable compartment door 16 is opened and the upper container 50 is pulled out to the front of the vegetable compartment 12, and then the vegetable compartment door 16 is closed, the front-rear partition wall 27 of the lower container 23 abuts against the protrusion 55 of the upper container 50, moving the upper container 50 rearward.

As shown in Figure 2, the lid 80 includes a plate portion 81, support portions 84 and 85, a heating portion 86, and a temperature detection portion 87, and is attached to the partition plate 4 that forms the ceiling surface of the vegetable compartment 12.

The plate portion 81 is a generally flat plate that covers and closes the entire top opening 51 of the upper container 50. The lower peripheral edge of the plate portion 81 forms a flat surface and is in surface contact with the entire peripheral edge of the top opening 51 of the upper container 50.

The support portions 84, 85 include a front support portion 84 located forward of the center position of the plate portion 81 in the front-to-rear direction, and a rear support portion 85 located rearward of the front support portion 84. These support portions engage with the partition plate 4 separating the refrigerator compartment 10 and vegetable compartment 12, supporting the plate portion 81 so that it can move up and down within the vegetable compartment 12.

The heating unit 86 and temperature detection unit 87 are attached to the plate unit 81. The heating unit 86 heats the food stored in the upper container 50 from above, and the temperature detection unit 87 detects the temperature of the food stored in the upper container 50. The heating unit 86, together with the refrigerated cooler 30, functions as a temperature adjustment means for adjusting the temperature of the food stored in the upper container 50.

Various heat sources can be used for the heating section 86, but it is preferable to use a heat source that emits radiant heat, such as a halogen heater or ceramic heater, to heat the food stored in the upper container 50.

The lid 80 may be provided with an insulating material 88 that covers the heating unit 86 from the outside of the upper container 50 (in this embodiment, from above the heating unit 86). This prevents heat from the heating unit 86 from leaking outside the upper container 50.

To open the top opening 51 of such an upper container 50 when the vegetable compartment door 16 is closed as shown in Figure 2, first open the vegetable compartment door 16. Because the upper container 50 is supported by the container's upper legs 52 resting on the inner box rails 25, opening the vegetable compartment door 16 causes the lower container 23 to be pulled out, but the upper container 50 remains in the vegetable compartment 12 with its top opening 51 blocked by the lid 80.

When the upper container 50 stored in the vegetable compartment 12 is pulled forward, the upper container 50 is pulled out of the refrigerator. Because the lid 80 is supported by the front support portion 84 and the rear support portion 85 so that it can move up and down, when the upper container 50 is pulled out of the refrigerator, the upper end of the upper container 50 abuts against the front positioning portion 82 provided on the lid 80, and the upper container 50 moves forward while lifting the front end of the lid 80 upward.

Next, to store the upper container 50 that has been pulled out of the cabinet into the vegetable compartment 12, the vegetable compartment door 16 is closed. This causes the front and rear partition wall 27 of the lower container 23 to abut against the protrusion 55 of the upper container 50, moving the upper container 50 rearward. At this time, a sloped portion (not shown) provided at the rear end of the upper container 50 scoops up the front positioning portion 82 and guides it to the top surface of the upper container 50. The upper container 50 then slides rearward along the underside of the lid 80, causing the top opening 51 of the upper container 50 to be closed by the lid 80.

(3) Control of Refrigerator 1 As shown in Fig. 3, the control unit 45 provided on the top of the refrigerator main body 2 is electrically connected to electrical components provided in the refrigerator main body 2, such as the operation and display unit 6, refrigeration blower 31, freezer blower 39, defrosting and heating unit 40, compressor 44, switching valve 46, refrigeration temperature sensor 60, door sensor 61, freezer temperature sensor 62, heating unit 86, and temperature detection unit 87. When signals are input from various sensors or signals are input from a user communication terminal that can communicate with the operation and display unit 6 and the refrigerator 1 by a user operation, the control unit 45 controls the overall operation of the refrigerator 1 based on a control program previously stored in memory.

Specifically, the control unit 45 alternately switches between refrigeration cooling operation and freezing cooling operation, and when predetermined defrosting start conditions are met, it performs defrosting operation to melt and remove frost that has adhered to the refrigeration cooler 30 and freezing cooler 38. Furthermore, when predetermined conditions are met, the control unit 45 performs fruit and vegetable preservation operation.

In principle, the refrigerator 1 of this embodiment will always be in either refrigeration/cooling mode or freezing/cooling mode, but the refrigeration/cooling mode or freezing/cooling mode may be stopped when certain conditions are met, such as when the second defrosting mode (described below) is in operation or when the temperatures of both the refrigerated and freezer spaces fall below a certain temperature.

(3-1) Refrigerating Cooling Operation When the refrigerating cooling start conditions are satisfied, the control unit 45 starts the refrigerating cooling operation by driving the compressor 44 at a predetermined frequency, opening the outlet on the refrigerating refrigerant flow path side of the switching valve 46 to allow the refrigerant to flow into the refrigerating cooler 30, and rotating the refrigerating blower 31. An example of the refrigerating cooling start condition is when the temperature detected by the refrigerating temperature sensor 60 becomes equal to or higher than the ON temperature (for example, 5°C) set for the refrigerated space.

During refrigeration cooling operation, low-pressure, low-temperature refrigerant flows into the refrigeration cooler 30 and vaporizes to generate cold air. The generated cold air circulates within the refrigerator compartment 10 and vegetable compartment 11 due to the blowing action of the refrigerator blower 31, cooling the lower container 23 and upper container 50 in the refrigerator compartment 10 and vegetable compartment 11 to the specified refrigeration temperature range.

Specifically, as the refrigerator blower 31 rotates, the cold air generated by the refrigerator cooler 30 is supplied to the refrigerator compartment 10 through the outlet 34a of the duct 34, cooling the refrigerator compartment 10. A portion of the cold air that flows through the refrigerator compartment 10 flows into the return duct from the intake port located at the rear of the partition plate 4 and returns to the refrigerator cooler compartment 33, while the remaining air flows into the vegetable compartment 11 through the connecting passage 4a located in the partition plate 4. The cold air that flows into the vegetable compartment 11 flows around the lower container 23 and the upper container 50, indirectly cooling the interiors of the lower container 23 and the upper container 50, then returns to the refrigerator cooler 30 from the intake port located at the rear of the vegetable compartment 11 through the return duct, where it is cooled and then blown back into the refrigerator compartment 10 through the outlet 34a.

If a refrigeration cooling termination condition is met during refrigeration cooling operation, the control unit 45 terminates the refrigeration cooling operation. One example of a refrigeration cooling termination condition is when the temperature detected by the refrigeration temperature sensor 60 reaches the OFF temperature (e.g., 2°C) set for the refrigerated space.

When the refrigeration cooling operation is completed, the control unit 45 drives the compressor 44 at a predetermined frequency while opening the outlet of the switching valve 46 on the refrigeration refrigerant flow path side to allow the refrigerant to flow into the refrigeration cooler 38, and then rotates the refrigeration blower 39 to start the refrigeration cooling operation.

(3-2) Freezing and cooling operation In freezing and cooling operation, cold air is generated by vaporizing the low-pressure, low-temperature refrigerant that has flowed into freezing cooler 38. The generated cold air is circulated through the ice making compartment, first freezing compartment 13, and second freezing compartment 14 by the blowing action of freezing blower 39, and cools the ice making compartment, first freezing compartment 13, and second freezing compartment 14 to a predetermined freezing temperature range.

The cold air circulated through the ice-making compartment, first freezer compartment 13, and second freezer compartment 14 returns to the freezer cooler 38 through a return duct from an intake port on the back of the second freezer compartment 14, where it is cooled and then blown back into the ice-making compartment, first freezer compartment 13, and second freezer compartment 14.

When a freeze-cooling termination condition is satisfied during the freeze-cooling operation, the control unit 45 terminates the freeze-cooling operation. For example, the freeze-cooling termination condition is satisfied when the temperature detected by the freeze-temperature sensor 62 reaches the OFF temperature (for example, −21° C.) set for the freezer space.

Then, when the freezing and cooling operation is completed, the control unit 45 starts the refrigerating and cooling operation.

(3-3) Defrosting Operation In the refrigerator 1, while switching between the refrigeration/cooling operation and the freezing/cooling operation, if a predetermined defrosting start condition is satisfied, the first defrosting operation and the second defrosting operation are performed.

The first defrosting operation melts and removes frost adhering to the refrigerated cooler 30, and supplies the moisture from the melted frost to the refrigerated space to humidify it. Specifically, the control unit 45 closes the outlet of the switching valve 46 on the refrigerated refrigerant flow path side and stops the compressor 44, thereby stopping the supply of refrigerant to the refrigerated cooler 30 and driving the refrigerated blower 31.

As a result of these controls, the air in the refrigerated space exchanges heat with the frost-covered refrigerated cooler 30, and then is returned to the refrigerator compartment 10 and vegetable compartment 11. This raises the temperature of the refrigerated cooler 30, melting the frost that has adhered to the refrigerated cooler 30, and the moisture in the melted frost is vaporized and blown into the refrigerator compartment 10 and vegetable compartment 11. As a result, humidified air with a higher relative humidity than the cold air blown into the refrigerator compartment 10 and vegetable compartment 11 during the above-mentioned refrigerated cooling operation is supplied to the refrigerator compartment 10 and vegetable compartment 11, humidifying the refrigerator compartment 10 and vegetable compartment 11.

The second defrosting operation is an operation in which frost adhering to the freeze-cooler 38 is removed by melting it. Specifically, the control unit 45 closes the outlet on the refrigerant flow path side of the switching valve 46 and stops the compressor 44, thereby stopping the supply of refrigerant to the freeze-cooler 38, stopping the freeze-cooler blower 39, and energizing the defrost heating unit 40. Through these controls, the freeze-cooler 38 is heated by the heat from the defrost heating unit 40, melting the frost adhering to the freeze-cooler 38. The defrost water generated by the melting frost is received by the drainage gutter 41 and discharged into the evaporator tray 37 provided in the machine room 36.

(3-4) Fruit and vegetable preservation operation The refrigerator 1 performs a fruit and vegetable preservation operation in which a cooling preservation operation and a recovery operation are alternately performed in the upper container 50 that constitutes the fruit and vegetable storage compartment. The fruit and vegetable preservation operation may be performed when a predetermined start condition is met, such as when the user performs a predetermined operation on the operation display unit 6 or a user communication terminal to instruct the execution of the fruit and vegetable preservation operation, or when the control unit 45 detects that food has been stored in the upper container 50. Alternatively, the fruit and vegetable preservation operation may be performed constantly while the refrigerator 1 is powered on.

The refrigerated storage operation is an operation for cooling food stored in the upper container 50. When performing the refrigerated storage operation, the control unit 45 indirectly cools the interior of the upper container 50 with cold air supplied to the vegetable compartment 11, and drives the heating unit 86 as needed, so that the temperature of the food detected by the temperature detection unit 87 reaches the first temperature Te1.

The control unit 45 continues to perform the refrigeration operation for the first time Ti1, thereby cooling the food stored in the upper container 50 at the first temperature Te1 for the first time Ti1, and then ends the refrigeration operation and starts the recovery operation.

The recovery operation is an operation that heats the temperature of food stored in the upper container 50 to a second temperature Te2, which is higher than the first temperature Te1, and is an operation that is intended to recover from low-temperature damage that has occurred to the food stored in the upper container 50 during the refrigerated storage operation. When performing the recovery operation, the control unit 45 drives or stops the heating unit 86 so that the temperature of the food detected by the temperature detection unit 87 reaches the second temperature Te2, which is higher than the first temperature Te1.

The control unit 45 continues to perform recovery operation for the second time Ti2, maintaining the food stored in the upper container 50 at the second temperature Te2 for the second time Ti2, and then ends the recovery operation and starts refrigerated storage operation. Thereafter, the control unit 45 alternates between refrigerated storage operation for the first time Ti1 and recovery operation for the second time Ti2.

If an end condition is met during the fruit and vegetable preservation operation, the control unit 45 ends the fruit and vegetable preservation operation. Examples of end conditions include when the user performs a predetermined operation on the operation display unit 6 or user communication terminal to instruct the end of the fruit and vegetable preservation operation, or when the control unit 45 detects that food has been removed from the upper container 50.

Even during the refrigeration storage operation and recovery operation, the control unit 45 alternately switches between the refrigeration cooling operation and the freezing cooling operation. Therefore, even during the refrigeration storage operation or recovery operation, while the refrigeration cooling operation is being performed, the cold air generated by the refrigeration cooler 30 is supplied to the vegetable compartment 11 via the refrigerator compartment 10, thereby indirectly cooling the inside of the upper container 50.

The first temperature Te1 set during refrigeration operation can be set to a temperature equal to or higher than the freezing temperature Tf (e.g., Tf = 0°C) of the food stored in the upper container 50 and equal to or lower than the critical temperature Tc of the food. The second temperature Te2 set during recovery operation can be set to a temperature higher than the critical temperature Tc of the food stored in the upper container 50.

The critical temperature Tc of a food product can be determined as follows: mannitol solutions are prepared at different temperatures in 1°C increments between 1°C and 20°C, and food tissue is immersed in the solution at each temperature for 30 minutes. The amount of ions leaking from the food tissue into the solution is measured using an electrical conductivity meter to determine the electrolyte leakage rate at each temperature. An Arrhenius plot of the electrolyte leakage rate is then created from the electrolyte leakage rate at each temperature, and the inflection point on this plot can be determined as the critical temperature Tc of the food product.

It is anticipated that the household refrigerator 1 will store a variety of foods with different critical temperatures Tc. Therefore, the critical temperature Tc may be set to a temperature selected from the range of 8 to 15°C. In this case, the critical temperature Tc may be set to a temperature higher than the lowest temperature reached by the front end of the top shelf 5 of the refrigerator compartment 10 when the cooling strength of the refrigerator compartment 10 is set to the lowest, or higher than the lowest temperature reached by the upper front end of the vegetable compartment 11 when the cooling strength of the refrigerator compartment 10 is set to the lowest, or higher than the ON temperature set as the refrigeration cooling start condition.

Also, when selecting the critical temperature Tc from 2 to 15°C, the temperature selected by the user may be set as the critical temperature Tc. Alternatively, a correspondence table between foods and critical temperatures Tc may be stored in advance in the refrigerator 1 or in a storage device or user communication terminal that can communicate with the refrigerator 1, and the critical temperature Tc corresponding to the food selected by the user on the operation display unit 6 or user communication terminal may be read from the correspondence table and set as the critical temperature Tc.

It is preferable to set the first temperature Te1 and the second temperature Te2 so that the temperature difference Δ2 (= Te2 - Tc) between the second temperature Te2 and the critical temperature Tc is smaller than the temperature difference Δ1 (= Tc - Te1) between the first temperature Te1 and the critical temperature Tc. For example, if the critical temperature Tc is 10°C, the first temperature Te1 can be set to 2-5°C, and the second temperature Te2 can be set to 11-14°C.

The time (second time) Ti2 for performing recovery operation is preferably the same as or longer than the time (first time) Ti1 for performing cooled storage operation, and the time for continuously performing cooled storage operation is preferably 24 hours or less. For example, the first time Ti1 can be set to 10 hours or more and 24 hours or less, and the second time Ti2 can be set to 18 hours or more and 48 hours or less.

Furthermore, it is preferable that the repeat cycle of the cooling storage operation and the recovery operation, i.e., the sum of the time Ti1 for performing one cooling storage operation and the time Ti2 for performing one recovery operation (Ti1 + Ti2), be longer than the repeat cycle of the refrigeration cooling operation and the freezing cooling operation, i.e., the total time for performing one refrigeration cooling operation and one freezing cooling operation.

(4) Effects The refrigerator 1 of this embodiment performs a cooling preservation operation to cool the upper container 50 and a recovery operation to maintain the upper container 50 at a temperature higher than that during the cooling preservation operation to recover from low-temperature damage to food stored in the upper container 50. This prevents low-temperature damage to food and reduces loss of freshness, allowing food to be stored while maintaining its quality.

In this embodiment, the temperature difference between the temperature Te2 during recovery operation and the critical temperature Tc is smaller than the temperature difference between the temperature Te1 during cooling and storage operation and the critical temperature Tc, so the inside of the refrigerator 1 is not unnecessarily heated and low-temperature damage can be suppressed.

In this embodiment, the execution time Ti2 of the recovery operation is equal to or longer than the execution time Ti1 of the refrigeration operation, ensuring the time necessary to recover from low-temperature damage to food.

(5) Modifications In the above embodiment, a case where fruit and vegetable preservation operation is performed in the upper container 50 is described, but a heating unit may be provided in the chilled compartment or the first freezer compartment 13 provided in the refrigerator compartment 10, and fruit and vegetable preservation operation may be performed in the chilled compartment or the first freezer compartment 13.

1...refrigerator, 2...refrigerator body, 3...insulating partition wall, 4...partition plate, 5...mounting shelf, 10...refrigerating compartment, 11...vegetable compartment, 13...first freezer compartment, 14...second freezer compartment, 20...storage container, 23...lower container, 30...refrigerated cooler, 31...refrigerated blower, 33...refrigerated cooler compartment, 38...freezer cooler, 39...freezer blower, 44...compressor, 45...control unit, 50...upper container, 80...lid, 81...plate, 82...front support, 86...heating unit, 87...temperature detection unit

Claims (6)

a storage compartment, a temperature adjusting means for adjusting the temperature of food stored in the storage compartment, and a control unit for controlling the temperature adjusting means;
In a household refrigerator, the control unit executes a cooled storage operation in which the food is cooled to a first temperature, and a recovery operation in which the food is heated to a second temperature higher than the first temperature to recover from low-temperature damage caused to the food,
the first temperature is equal to or higher than the freezing temperature of the food product and equal to or lower than a critical temperature, and the second temperature is higher than the critical temperature;
a temperature difference between the second temperature and the critical temperature is smaller than a temperature difference between the first temperature and the critical temperature;
The household refrigerator alternately repeats the cooling preservation operation and the recovery operation at a temperature of 0°C or higher . The domestic refrigerator according to claim 1 , wherein the critical temperature is variable . 3. The household refrigerator according to claim 2, wherein the critical temperature can be changed according to a user's selection. A household refrigerator according to any one of claims 1 to 3, wherein the execution time of the recovery operation is longer than the execution time of the cooling storage operation. A household refrigerator according to any one of claims 1 to 3, wherein the execution time of the recovery operation is equal to the execution time of the cooling storage operation. A household refrigerator according to any one of claims 1 to 5, wherein the cooling storage operation is continuously performed for 24 hours or less.