WO2020084866A1 - Refrigerator - Google Patents

Abstract

This refrigerator provided with a cooling/heating chamber that can cool and heat food comprises: a heating unit that heats food by heating the cooling/heating chamber; and a heated food detecting unit that detects, after food has been heated, whether the heated food is in the cooling/heating chamber. The cooling temperature for cooling operations of the cooling/heating chamber is changed on the basis of the detection results of the heated food detecting unit.

Description

refrigerator

The present invention relates to a refrigerator capable of thawing food.

For example, Patent Document 1 discloses a freezer capable of thawing frozen food. The freezer of Patent Document 1 has a high-frequency heating chamber in which food to be thawed is stored and which is subjected to high-frequency heating (dielectric heating). The high frequency heating chamber is configured to be able to introduce cold air from the freezing chamber. Thereby, when not used for thawing, the high frequency heating chamber is used as a freezing chamber.

Japanese Patent Laid-Open No. 2002-147919

By the way, in the freezer described in Patent Document 1, when the defrosted food is stored in the high frequency heating chamber as it is, the user operates the temperature control switch to set the high frequency heating chamber to a temperature suitable for storage, for example, a refrigeration temperature. There is a need to. Therefore, when the user forgets to thaw the food, there is a possibility that the temperature control switch is not operated and the thawed food is left in the high-frequency heating chamber that is not at an appropriate temperature.

Therefore, an object of the present invention is to appropriately store a heated food that is heated in the cooling / heating chamber and left as it is in a refrigerator including a cooling / heating chamber capable of cooling and heating food.

In order to solve the above problems, according to one aspect of the present invention,
A refrigerator having a cooling / heating chamber capable of cooling and heating food, comprising:
A heating unit for heating the food by heating the cooling / heating chamber;
After the heating of the food is finished, a heated food detection unit for detecting whether or not the heated food is present in the cooling / heating chamber,
There is provided a refrigerator that changes a cooling temperature of a cooling operation of the cooling / heating chamber based on a detection result of the heated food detection unit.

According to the present invention, in a refrigerator provided with a cooling / heating chamber capable of cooling and heating food, it is possible to appropriately store the heated food heated in the cooling / heating chamber and left as it is.

These aspects and features of the present invention will become apparent from the following description in connection with the preferred embodiments of the accompanying drawings. In this drawing,
Vertical sectional view of a refrigerator according to an embodiment of the present invention Block diagram showing the control system of the refrigerator Enlarged sectional view of the freeze / thaw chamber Enlarged sectional view of the freeze / thaw chamber showing the flow of cold air Cross section of heating module Sectional view of a portion of the body of the refrigerator before the heating module is installed Exploded sectional view of heating module Sectional view of the heating module along the line AA in FIG. Block diagram showing the control system of the heating unit of the heating module Diagram showing changes in reflectance during food thawing Timing chart of normal operation Timing chart of rapid cooling operation Timing chart of zone defrosting operation Timing chart of all zone defrosting operation Flow chart of zone defrosting operation (all zone defrosting operation)

A refrigerator according to an aspect of the present invention is a refrigerator including a cooling / heating chamber capable of cooling and heating food, and a heating unit that heats the cooling / heating chamber to heat the food, and heating of the food. After completion, a heated food detection unit that detects whether or not heated food exists in the cooling / heating chamber, and based on the detection result of the heated food detection unit, the cooling / heating chamber Change the cooling temperature of the cooling operation of.

According to this aspect, in a refrigerator including a cooling / heating chamber capable of cooling and heating food, it is possible to appropriately store the heated food heated in the cooling / heating chamber and left as it is.

For example, when the heated food detection unit does not detect the heated food, the normal operation of maintaining the cooling temperature of the cooling operation of the cooling / heating chamber at the first cooling storage temperature may be executed.

For example, when the heated food is detected by the heated food detecting unit, the cooling temperature of the cooling operation of the cooling / heating chamber is set to the second cooling storage temperature higher than the first cooling storage temperature. You may perform the 2nd cooling preservation operation maintained.

For example, after a lapse of a predetermined time from the end of heating, the second cooling storage operation may be switched to the normal operation. This prevents the heated food from being stored at the second cooling storage temperature for a long time.

For example, the cooling / heating chamber has a heating zone that is a space in which food to be heated is placed, and a non-heating zone that is a space continuous to the heating zone and in which food to be unheated is placed. When divided, the heating unit applies an AC voltage between the oscillation electrode and the counter electrode arranged to face each other across the heating zone of the cooling / heating chamber, and the oscillation electrode and the counter electrode. And an oscillating portion for heating the food between them. In this case, when the heated food is detected by the heated food detection unit, by heating the heated food by the heating unit while maintaining the cooling / heating chamber at the first cooling storage temperature. , Maintaining the cooked food at the second cold storage temperature. Thereby, the heated food can be brought to the second cold storage temperature while the food in the non-heating zone is stored at the first cold storage temperature.

For example, the heated food detection unit is a reflection wave detection unit that detects a reflection wave returning to the oscillation unit, and a reflectance calculation that calculates a reflectance that is a ratio of the reflection wave to the incident wave output from the oscillation unit. The heated food detection unit, the reflectance is a value that is smaller than a value when the heated food is not present between the oscillation electrode and the counter electrode. The cooked food may be detected if it is smaller than a threshold value. Thereby, the heated food can be detected.

For example, a refrigerator has a door that opens and closes the cooling / heating chamber and a door sensor that detects opening and closing of the door, and the heated food detection unit detects that the door opening and closing sensor has opened the door. If not, the cooked food may be detected. Thereby, the heated food can be detected.

For example, when the refrigerator reaches a second threshold value that is a value smaller than the first threshold value while the reflectance increases while the heating unit is heating the food, The impedance matching between the oscillation electrode and the counter electrode is provided, and the impedance matching causes the reflectance to exceed a third threshold value that is smaller than the second threshold value. If it does not decrease, the execution timing of the impedance matching may be the heating end timing of the food. As a result, the second cooling storage operation can be started after the food is heated.

For example, the refrigerator has an operation unit for the user to input a heating time while receiving a heating start instruction, and the timing when the heating time elapses from the timing when the user receives the start instruction It may be the end timing. As a result, the second cooling storage operation can be started after the food is heated.

Hereinafter, a refrigerator according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a vertical cross-sectional view of the refrigerator according to the present embodiment. In FIG. 1, the left side is the front side of the refrigerator and the right side is the back side of the refrigerator. FIG. 2 is a block diagram showing the control system of the refrigerator.

As shown in FIG. 1, the refrigerator 10 includes a main body 12. The main body 12 is made of a metal material and forms an outer surface of the refrigerator 10, and an outer housing 14, an inner housing 16 that is made of a resin material such as ABS and forms an inner surface of the refrigerator 10, and an outer housing. The space between the body 14 and the inner casing 16 is filled with a heat insulating material 18 such as hard urethane foam.

The main body 12 of the refrigerator 10 has a plurality of storage rooms for storing foods (foodstuffs, processed foods, etc.). In the case of the present embodiment, as the storage chambers, a refrigerating chamber 12a, a freezing / thawing chamber 12b, a freezing chamber 12c, and a vegetable chamber 12d are provided from the top. Although not shown, an ice making chamber in which ice is made is provided on the right side (the inner side of the drawing) of the freezing / thawing chamber 12b. The refrigerator 10 can also store articles other than food.

The refrigerating room 12a is a space maintained in a temperature range where food does not freeze, for example, a temperature range of 1 ° C to 5 ° C. The freezer compartment 12c is a space which is maintained in a temperature zone where food is frozen, for example, in a temperature zone of -22 ° C to -15 ° C. The vegetable compartment 12d is a space maintained at a temperature zone equal to or higher than that of the refrigerating compartment 12a, for example, 2 ° C to 7 ° C. The freezing / thawing chamber 12b will be described later.

In the case of this embodiment, a machine room 12e is provided above the main body 12 of the refrigerator 10. The machine room 8 accommodates a compressor 20 that constitutes a refrigeration cycle of the refrigerator 10 and circulates the refrigerant of the refrigeration cycle. Alternatively, the machine room 12e may be provided in the lower portion of the main body 12 of the refrigerator 10.

In the case of the present embodiment, a cooling chamber 12f is provided on the back side of the freezing chamber 12c and the vegetable chamber 12d. Inside the cooling chamber 12f, a cooler 22 that constitutes a refrigeration cycle of the refrigerator 10 and through which a refrigerant passes is arranged. In addition, a cooling fan 24 that blows air (cool air) cooled by the cooler 22 toward the refrigerating room 12a, the freezing / thawing room 12b, the freezing room 12c, and the vegetable room 12d is supplied to the cooling room 12f. It is provided. Further, as shown in FIG. 2, dampers 26A to 26D for controlling the flow rates of the cool air flowing into the chambers 12a to 12d are arranged in the flow path between the chambers 12a to 12d and the cooling fan 24 (see FIG. 1 only the damper 26B is shown).

Furthermore, as shown in FIG. 2, temperature sensors 28A to 28D for measuring the internal temperature of each of the refrigerating room 12a, the freezing / thawing room 12b, the freezing room 12c, and the vegetable room 12d are provided.

As shown in FIG. 2, the control unit 30 of the refrigerator 10 executes cooling control based on the measurement results of the plurality of temperature sensors 28A to 28D, that is, output control of the compressor 20 and rotation speed control of the cooling fan 24. , And each of the dampers 26A to 26D are controlled so that the temperatures in the refrigerating room 12a, the freezing / thawing room 12b, the freezing room 12c, and the vegetable room 12d are appropriately maintained. The control unit 30 is a board provided with a processor such as a CPU, a storage device such as a memory for storing programs, and a circuit, and the processor is a compressor 20 or a cooling fan according to the programs stored in the storage device. 24 and the dampers 26A to 26D.

As shown in FIG. 2, in the case of the present embodiment, the refrigerator 10 is provided with an operation unit 32 for the user to operate the refrigerator 10, particularly the freezing / thawing chamber 12b. The operation unit 32 may be a touch panel incorporated in the refrigerator 10 and / or a user's mobile terminal. When the operation unit 32 is a mobile terminal, software (application) for operating the refrigerator 10 is installed in the mobile terminal. Details of the freezing / thawing chamber 12b will be described below.

FIG. 3 is an enlarged sectional view of the freezing / thawing chamber 12b. FIG. 4 is an enlarged sectional view of the freezing / thawing chamber 12b showing the flow of cold air. The flow of cold air is indicated by the alternate long and short dash line.

As shown in FIG. 3, in the case of the present embodiment, the freezing / thawing chamber 12b is configured by the heating module 40 incorporated in the main body 12 of the refrigerator 10.

FIG. 5 is a sectional view of the heating module, and FIG. 6 is a sectional view of a part of the main body of the refrigerator before the heating module is incorporated. FIG. 7 is an exploded sectional view of the heating module. FIG. 8 is a cross-sectional view of the heating module taken along the line AA of FIG.

As shown in FIGS. 5 and 8, the heating module 40 has a rectangular parallelepiped shape and is a double-walled structure including an inner case 42 and a shield case 44 that accommodates the inner case 42. The shield case 44 functions as a housing of the heating module 40. The inner case 42 defines a storage chamber in which food is stored, that is, a freezing / thawing chamber 12b.

The inner case 42 is made of an insulating material such as resin and has a box shape with an opening on the front side. The shield case 44 is made of a material containing metal, and is made of a metal material such as aluminum. Further, the shield case 44 has a box shape having an opening on the front side and storing the inner case 42.

In the case of the present embodiment, as shown in FIG. 7, the heating module 40 includes a drawer 46 that is put in and taken out of the freezing / thawing chamber 12b and stores food. Specifically, the drawer 46 includes a storage portion 46a in which food is stored, and a door portion 46b that is provided in front of the storage portion 46a and that opens and closes the freezing / thawing chamber 12b. The housing portion 46a is made of a resin material. Further, a metal rail 48 for guiding the drawer 46 at the time of taking in and out is provided on the inner wall surface of the inner case 42. Such a drawer 46 makes it easy to put food in and out of the freezing / thawing chamber 12b.

In the case of the present embodiment, as shown in FIGS. 3 and 4, the heating module 40 has a cold air inlet hole for introducing cold air (dashed line) into the freezing / thawing chamber 12b therein and the freezing / thawing chamber 12b. A cold air outlet hole for discharging the cold air therein is provided. Specifically, as the cold air inlet holes of the heating module 40, a plurality of through holes 44a formed in the ceiling portion of the shield case 44 and a through hole 42a formed in the ceiling portion of the inner case 42 are provided. . By these through holes 42a and 44a, it is possible to introduce cool air, which is blown by the cooling fan 24, passes through the damper 26B and flows through the flow path 12g, into the freezing / thawing chamber 12b.

As the cold air outlet holes of the heating module 40, a plurality of through holes 42b formed at the bottom of the inner case 42 and a plurality of through holes 44b formed at the bottom of the shield case 44 are provided. By these through holes 42b and 44b, the cold air in the freezing / thawing chamber 12b can be returned to the cooling chamber 12f.

In the case of the present embodiment, the cool air flowing out from the through holes 42b and 44b as the cool air outlet holes returns to the cooling chamber 12f via the freezing chamber 12c. Therefore, as shown in FIG. 6, the partition wall 12j in the main body 12 of the refrigerator 10 separating the space 12h in which the cooling / thawing chamber 12b is incorporated and the freezing chamber 12c is penetrated to connect the space 12h and the freezing chamber 12c. A hole 12k is provided.

Further, as shown in FIGS. 4 and 8, the accommodating portion 46a of the drawer 46 has at least one of a bottom portion and a side wall portion thereof so that the cool air in the drawer 46 can smoothly flow into the cooling chamber 12f (that is, the freezing chamber 12c). Further, it is preferable to provide a through hole 46c penetrating from the inside of the drawer 46 toward the outside. In the case of the present embodiment, as the through holes 46c, a plurality of slit holes 46c that extend in the up-down direction and are arranged in the left-right direction are provided in the rear side wall portion of the drawer 46.

As shown in FIG. 2, the heating module 40 includes a heating unit 50 in order to thaw the frozen food in the freezing / thawing chamber 12b.

FIG. 9 is a block diagram showing the control system of the heating unit of the heating module.

As shown in FIG. 5, the heating module 40 includes an oscillating electrode 52 and a counter electrode (counter electrode part) 54 facing the oscillating electrode 52, as components of the heating unit 50.

In the case of the present embodiment, the oscillation electrode 52 is a plate-shaped electrode made of a metal material as shown in FIG. 8, and the ceiling part of the inner case 42 and the ceiling of the shield case 44 as shown in FIG. It is located in the space between the department. Further, the oscillation electrode 52 has a plurality of cold air passage holes 52a through which cold air passes. The cold air passage hole 52a allows the oscillation electrode 52 to be cooled by the cold air, and also allows the cold air to be introduced into the region of the freezing / thawing chamber 12b located below the oscillation electrode 52.

In the case of the present embodiment, the counter electrode 54 is a part 44c of the bottom of the shield case 44. The counter electrode 54 (portion 44c) is vertically opposed to the oscillation electrode 52 with the inner case 42, that is, the freezing / thawing chamber 12b interposed therebetween. The oscillation electrode and the counter electrode do not have to have the same area.

As shown in FIG. 9, the heating unit 50 is controlled by the control unit 30 to apply an AC voltage of a predetermined VHF band frequency, for example, 40.68 MHz, between the oscillation electrode 52 and the counter electrode 54. The oscillator 56). Specifically, the oscillation circuit 56 is a circuit formed on the substrate and is electrically connected to the oscillation electrode 52 and the counter electrode 54. Further, the oscillation circuit 56 converts the AC voltage from the power supply unit 58 of the refrigerator 10 connected to the commercial power supply and applies the converted AC voltage between the oscillation electrode 52 and the counter electrode 54.

By applying the AC voltage, an alternating electric field is generated between the oscillation electrode 52 and the counter electrode 54. This alternating electric field dielectrically heats the food arranged between the electrodes 52 and 54, that is, the food contained in the drawer 46 in the freezing / thawing chamber 12b. As a result, the frozen food is thawed.

In the case of the present embodiment, as shown in FIGS. 3 and 5, the oscillation electrode 52 and the counter electrode 54 do not face each other across the entire freezing / thawing chamber 12b, but face each other across a part thereof. It is arranged to. As a result, the freezing / thawing chamber 12b is divided into a thawing zone (heating zone) DZ (a region indicated by cross-hatched dashed lines), which is a space in which food to be thawed (heating target) is placed, and a thawing zone DZ. On the other hand, it is a continuous space and is divided into a non-thawing zone (non-heating zone) NDZ in which a non-thawing target (non-heating target) food is placed. That is, the thawing zone DZ exists and the non-thawing zone NDZ does not exist between the oscillation electrode 52 and the counter electrode 54.

By dividing the freezing / thawing chamber 12b into the thawing zone DZ and the non-thawing zone NDZ in this way, it is possible to thaw only a part of the plurality of foods stored in the freezing / thawing chamber 12b. Therefore, when thawing, it is not necessary to move food that is not desired to be thawed from the freezing / thawing chamber 12b, for example, to the freezing chamber 12c. Further, when the operation unit 32 is configured to be able to reserve the start time of thawing, the food placed in the thawing zone DZ is kept in a frozen state until thawing is started, and then automatically thawed. To be done.

Further, in the case of the present embodiment, the thawing zone DZ is located on the front side of the refrigerator 10 with respect to the non-thawing zone NDZ. Therefore, the food thawed in the thawing zone DZ can be immediately taken out.

In order to indicate to the user that the food to be defrosted is placed in the defrosting zone DZ, a presentation unit that presents to the user that the portion of the drawer 46 placed in the defrosting zone DZ is the place to place the food to be defrosted. Is preferably provided. The presentation unit may be, for example, an image or characters printed on the bottom surface of the drawer 46. Further, for example, the presentation unit may be a partition wall provided in the drawer 46, which indicates the boundary between the thawing zone DZ and the non-thawing zone NDZ. The front-rear positional relationship between the defrosting zone DZ and the non-thawing zone NDZ may be reversed. In the opposite case, the distance of the connecting member 64 is shortened and the heating efficiency is improved.

As shown in FIG. 8, when the oscillation electrode 52 and the counter electrode 54 are opposed to each other (in the vertical direction of the refrigerator 10), the oscillation electrode 52 and the counter electrode 54 are arranged in the inner case 42 so as not to overlap the rail 48. It is preferably provided. On the other hand, when the rail 48 is present between the oscillation electrode 52 and the counter electrode 54, an alternating electric field is generated between the oscillation electrode 52 and the rail 48, and is generated between the oscillation electrode 52 and the counter electrode 54. The alternating electric field is weakened, and the uniformity of the electric field (uniformity of heating) is impaired.

Further, in the case of the present embodiment, the counter electrode 54 is a raised portion of the shield case 44 that is raised toward the oscillation electrode 52, and thus the counter electrode 54 is close to the oscillation electrode 52. As a result, a stronger alternating electric field can be generated as compared with the case where the counter electrode 54 is not a raised portion.

During the thawing of food, that is, when an alternating electric field is generated between the oscillation electrode 52 and the counter electrode 54, the shield case 44 functions as a shield member that shields the alternating electric field from leaking to the outside. As shown in FIG. 5, a metallic shield plate 46d is provided in the door portion 46b of the drawer 46 so that the alternating electric field does not leak to the outside through the opening on the front side of the shield case 44. The shield plate 46d and the shield case 44 surround and electromagnetically shield the freezing / thawing chamber 12b in which an alternating electric field is generated.

As shown in FIG. 9, the heating unit 50 also includes a matching circuit (matching unit) 60 that performs impedance matching between the oscillation electrode 52 and the counter electrode 54. Specifically, the matching circuit 60 is a circuit formed on the substrate and is electrically connected to the oscillation electrode 52 and the counter electrode 54. In the case of the present embodiment, the counter electrode 54 is grounded.

The role of the matching circuit 60 will be described. As the food is thawed, the number of water molecules in the food increases. As the number of water molecules increases, the impedance changes from the matched state and the reflectance increases. The reflectance is the ratio of the reflected wave returning to the oscillation circuit 56 to the incident wave output from the oscillation circuit 56.

FIG. 10 is a diagram showing changes in reflectance during thawing of food.

In FIG. 10, P1 to P5 are timings when the matching circuit 60 re-establishes impedance matching between the oscillation electrode 52 and the counter electrode 54. Further, R1 to R3 are threshold values of reflectance. In reality, instead of the reflectance, a threshold value of reflected power that is easy to detect may be provided for the determination.

When the food thawed, the reflectance increases with the passage of time. Each time the reflectance reaches the second threshold value R2, the matching circuit 60 re-establishes impedance matching between the oscillation electrode 52 and the counter electrode 54. As a result, the reflectance decreases. By repeatedly re-adjusting the impedance matching between the oscillation electrode 52 and the counter electrode 54 before the thawing of food is completed in this way, the loss of electric energy due to reflection can be suppressed and the food can be thawed efficiently. it can.

In order to calculate this reflectance, the heating unit 50 includes a reflected wave detection circuit 62, as shown in FIG. The control unit 30 as a reflectance calculation unit calculates the reflectance based on the incident wave output from the oscillation circuit 60 and the reflected wave detected by the reflected wave detection circuit 62. Each time the calculated reflectance reaches the second threshold value R2, the matching circuit 60 re-establishes impedance matching between the oscillation electrode 52 and the counter electrode 54.

In the case of the present embodiment, as shown in FIG. 5, the oscillation circuit 56, the matching circuit 60, and the reflected wave detection circuit 62 are incorporated in the heating module 40. The reflected wave detection circuit 62 is formed on the substrate on which the matching circuit 60 is formed.

Specifically, as shown in FIG. 5, the oscillation circuit 56 and the matching circuit 60 are arranged in a shield chamber 44d provided in the shield case 44. The shield chamber 44d is separated from the freezing / thawing chamber 12b by a partition wall 44e. By being arranged in such a shield chamber 44d, the oscillation circuit 56 and the matching circuit 60 are shielded from the alternating electric field generated in the freezing / thawing chamber 12b, and malfunction is suppressed.

The connection member 64 that electrically connects the matching circuit 60 and the oscillation electrode 52 penetrates the partition wall 44e. Further, as shown in FIG. 8, the size of the connecting member 64 in the left-right direction is smaller than that of the oscillation electrode 52. This is to suppress the generation of an alternating electric field between the connecting member 64 and the portion of the shield case 44 that faces the freezing / thawing chamber 12b. That is, as shown in FIG. 3, this is to prevent the food present in the non-thawing zone NDZ located below the connecting member 64 from being thawed.

Further, as shown in FIG. 5, the oscillator circuit 56 is provided with a connector 66 for connecting to the control unit 30 of the refrigerator 10. Further, the matching circuit 60 is also provided with a connector 68 for connecting to the control unit 30. As shown in FIG. 6, the connector 66 of the oscillation circuit 56 is provided in the space 12h of the main body 12 of the refrigerator 10 in which the heating module 40 is incorporated, and engages with the connector 70 connected to the control unit 30. In addition, the connector 68 of the matching circuit 60 engages with the connector 72 that is also provided in the space 12h and connected to the control unit 30. The engagement work of these connectors is performed through a through hole 12k that connects the space 12h and the freezer compartment 12c. That is, as shown in FIG. 4, the through hole 12k through which cold air flowing from the freezing / thawing chamber 12b to the freezing chamber 12c passes serves as an access hole for accessing the heating module 40.

As in the present embodiment, the advantage of incorporating the oscillation circuit 56 and the matching circuit 60 (the reflected wave detection circuit 62 included therein) together with the oscillation electrode 52 and the counter electrode 54 in the heating module 40 including the shield case 44 is as follows. It is possible to perform inspections such as these heating tests and noise (alternating electric field) leakage checks outside the refrigerator 10.

On the contrary, when the oscillation electrode, the counter electrode, the oscillation circuit, the matching circuit, the reflected wave detection circuit, and the shield component are installed inside the refrigerator body, the heating test and the noise leakage check are performed after they are all installed in the refrigerator body. It is necessary to perform inspections such as. Therefore, for example, when the result of the heating test is not good or when the noise leakage occurs, it is necessary to remove the circuit and the shield component built in the inside of the refrigerator body, which is very troublesome. Moreover, when noise leakage occurs, it is necessary to remove the shield member from the refrigerator body. As a result, the work of manufacturing the refrigerator including the inspection may be complicated.

Therefore, by modularizing the oscillation electrode 52, the counter electrode 54, the oscillation circuit 56, the matching circuit 60, the reflected wave detection circuit 62, and the shield case 44 as the heating module 40 in this way, it is possible to perform a heating test outside the refrigerator 10. Since the inspection such as the noise leakage check can be performed, the refrigerator 10 can be easily manufactured. Moreover, when the refrigerator housing is covered with a metal plate, there is a possibility that leakage noise cannot be detected from the outside because it is shielded by the metal plate. In that case, the risk that the electronic components between the metal plate and the heating module 40 do not operate normally due to the influence of leakage noise is overlooked, and the quality of the refrigerator cannot be confirmed.

Up to this point, the structure of the freeze / thaw chamber 12b has been described. From here, the operation (operation) for the food in the freezing / thawing chamber 12b of the refrigerator according to the present embodiment will be described.

In the case of the present embodiment, the control unit 30 performs a normal operation, a rapid cooling operation, a zone thawing operation (zone heating operation), an all-zone thawing operation, and a slight freezing operation on the food in the freezing / thawing chamber 12b. To do.

In normal operation, in order to store the food in the freezing / thawing chamber 12b in a frozen state, the temperature in the freezing / thawing chamber 12b is a frozen storage temperature (first cooling storage temperature), for example, a freezing temperature at which the food freezes. The operation is maintained at a temperature of -16 ° C to -20 ° C. That is, it is an operation of maintaining the temperature at the same level as the freezer compartment 12c.

FIG. 11 is a timing chart of normal operation.

As shown in FIG. 11, in normal operation, the compressor 20 is intermittently operated so as to maintain the temperature in the freezing / thawing chamber 12b at the frozen storage temperature Tf (to maintain the food temperature at Tf). In addition, the cooling fan 24 and the damper 26B are controlled.

Due to such intermittent operation of the compressor 20, when the compressor 20 is stopped (when OFF), the water content of the food is evaporated, and when the compressor 20 is operating (when ON). The food is frosted, which causes the food temperature to fluctuate widely.

When the food placed in the thawing zone DZ is frosted, a part of the food is dried and is frozen and deteriorates. Therefore, even if the thawing is performed in a high quality, the user can obtain a high quality food. I cannot provide it.

As a countermeasure, in the case of the present embodiment, when the compressor 20 is operating, the oscillation circuit 56 is turned on to apply an AC voltage between the oscillation electrode 52 and the counter electrode 54, and the compressor 20 is stopped. During this time, the oscillation circuit 56 is turned off to stop the application of the AC voltage, thereby reducing the temperature fluctuation of the food. The output of the oscillation circuit 56 at this time is, for example, 30% or more of the refrigerating capacity.

Due to such intermittent operation of the oscillation circuit 56 (that is, intermittent dielectric heating), it is possible to suppress frost from being generated in the food arranged in the thawing zone DZ, and as a result, thawing quality varies. Suppressed. In addition, it is possible to suppress the expansion of ice crystals inside the food arranged in the thawing zone DZ. When ice crystals are greatly extended inside the food, the cells and tissues of the food are damaged, and water is leaked from the damaged cells and tissues during thawing, which deteriorates the quality of the food. As a countermeasure against this, an electric field is collected at the tip of the ice crystal by dielectric heating to suppress the elongation of the crystal, and the size of the ice crystal can be suppressed to prevent physical deterioration of the food.

The rapid cooling operation is an operation for freezing (quenching) the food, which is to be newly frozen from now on, when the food is placed in the defrosting zone DZ of the freezing / thawing chamber 12b, as compared with the normal operation. Further, when the food is placed, the quenching operation is automatically started.

FIG. 12 is a timing chart of the rapid cooling operation.

The reflectance described above is used to detect that the food to be rapidly frozen is placed in the thawing zone DZ of the freezing / thawing chamber 12b. As shown in FIG. 12, the signal from the door open / close switch is used as a trigger to weakly operate the oscillation circuit 56 (small oscillation output), and the closing is determined based on the reflectance. After the determination of turning on, the oscillation circuit 56 is periodically operated to detect a change in reflectance, the frozen state is determined based on the detected change in reflectance, and the operation of the oscillation circuit 56 is controlled.

As shown in FIG. 12, when the food to be rapidly frozen is placed in the thawing zone DZ of the freezing / thawing chamber 12b (timing P6), the reflectance decreases. This is because the food to be rapidly frozen is arranged between the oscillation electrode 52 and the counter electrode 54, so that the dielectric constant between the oscillation electrode 52 and the counter electrode 54 increases.

In the case of the present embodiment, when the reflectance exceeds the first threshold value R1 and decreases, the control unit 30 determines that the food to be quickly frozen is placed in the defrosting zone DZ of the freezing / thawing chamber 12b. The quenching operation is started instead of the normal operation (timing P7).

When the rapid cooling operation is started, cooling control is continuously executed as shown in FIG. For example, the compressor 20 and the cooling fan 24 are continuously operated, and the damper 26B is kept open. It should be noted that if there is a surplus power, the output of the compressor 20 and the rotation speed of the cooling fan 24 may be increased as compared with during normal operation.

As shown in FIG. 12, when the reflectance decreases and reaches the second threshold value R2, the rate of change of the reflectance increases. This is because the food temperature has entered the maximum ice crystal production zone (for example, -1 to -5 ° C) where the ice crystals are likely to expand.

When the food temperature enters the maximum ice crystal formation zone (when the reflectance reaches the second threshold value R2), the oscillation circuit 56 of the heating unit 50 applies an AC voltage between the oscillation electrode 52 and the counter electrode 54. Start applying intermittently. At this time, the output of the oscillation circuit 56 is, for example, 1 to 10 W, which is smaller than the output during normal operation. By such dielectric heating by the heating unit 50, it is possible to freeze the food while suppressing the expansion of ice crystals in the food.

When the reflectance further decreases and reaches the third threshold value R3, the rate of change of the reflectance becomes small. This is because the food temperature reached the temperature just before passing through the maximum ice crystal formation zone. When the third threshold value R3 is reached and a predetermined time t1 has elapsed, the control unit 30 determines that the food temperature has passed the maximum ice crystal production zone, the cooling control returns to the control during normal operation, and the oscillation circuit The intermittent application of the AC voltage by 56 ends (timing P8). As a result, the rapid cooling operation ends and the normal operation is resumed.

The zone thawing operation (zone heating operation) is an operation in which only the food placed in the thawing zone DZ is thawed (heated) and the food placed in the non-thawing zone NDZ is maintained at the frozen storage temperature Tf. Unlike the rapid cooling operation, the zone defrosting operation is started when the operation unit 32 receives an instruction from the user to switch from the normal operation to the zone defrosting operation. For example, when the user presses the “zone defrost” button on the operation unit 32, the zone defrosting operation is started.

FIG. 13 is a timing chart of the zone defrosting operation.

As shown in FIG. 13, when the zone thawing operation is started, the oscillation circuit 56 of the heating unit 50 starts continuously applying the AC voltage between the oscillation electrode 52 and the counter electrode 54. As a result, the thawing of the food A arranged in the thawing zone DZ starts, and the temperature of the food A begins to rise.

On the other hand, the output of the compressor 20 so that the food B arranged in the non-thawing zone NDZ is maintained at the frozen storage temperature Tf, that is, the freezing / thawing chamber 12b is maintained at the frozen storage temperature Tf during normal operation. The rotation speed of the cooling fan 24 and the opening / closing of the damper 26B are controlled. For example, the damper 26B is repeatedly opened and closed so that the open state and the closed state continue for the same time.

Due to this, the food B placed in the non-thawing zone NDZ is frozen and stored as in the normal operation. In this zone defrosting operation, the output of the compressor 20 and the rotation speed of the cooling fan 24 are higher than in the normal operation in consideration of the temperature increase in the freezing / thawing chamber 12b caused by the dielectric heating by the heating unit 50. Also, the opening time of the damper 26B is long.

Further, according to such a zone thawing operation, the steam generated from the food A being thawed is discharged to the outside of the cooling / thawing chamber 12b by the damper 26B being intermittently opened. Thereby, the relative humidity of the cooling / thawing chamber 12b does not become 100%, and the generation of frost is suppressed.

When the thawing of the food A placed in the thawing zone DZ is completed, the zone thawing operation ends.

Note that in the case of the present embodiment, the end of thawing of food is judged based on the change in reflectance.

Looking at Fig. 10, which shows the change in reflectance during thawing of food, the reflectance immediately after impedance matching gradually rises as thawing progresses. For example, the reflectance at the timing P2 is higher than the reflectance at the timing P1. At the timing P5, unlike the timings P1 to P4 before that, the reflectance after impedance matching is higher than the third threshold value R3. By appropriately setting the third threshold value R3, when the reflectance lowered by the impedance matching is higher than the third threshold value R3, the execution timing P5 of the impedance matching is regarded as the defrosting end timing. be able to. Therefore, when the reflectance does not drop below the third threshold value due to the impedance matching, the control unit 30 determines that the thawing of the food has finished at the timing of executing the impedance matching, and finishes the zone thawing operation. When the zone defrosting operation is completed, it returns to normal operation. However, depending on the amount and physical properties of the food, the reflectance after matching may exceed R3 even if it is not thawed, or it may not reach R2 even after the thaw is completed. Therefore, the minimum operating time and the maximum operating time may be set regardless of the threshold values R2 and R3.

The all-zone defrosting operation is an operation that thaws (heats) not only the food in the freezing / thawing chamber 12b, that is, the food in the non-thawing zone DZ but also the food in the non-thawing zone NDZ. Similar to the zone defrosting operation, the all-zone defrosting operation is also started by the operation unit 32 receiving an instruction from the user to switch from the normal operation to the all-zone defrosting operation. For example, when the user presses the “decompress all zones” button on the operation unit 32, decompression operation for all zones is started.

FIG. 14 is a timing chart of the defrosting operation for all zones.

As shown in FIG. 14, the all-zone defrosting operation is the same as the zone defrosting operation shown in FIG. 12, except for the opening time of the damper 26B. Specifically, during the all-zone thawing operation, the damper 26B is generally closed in order to maintain the temperature of the freezing / thawing chamber 12b that is increased by the dielectric heating of the heating unit 50. However, the damper 26B is momentarily opened to reduce the humidity in the cooling / thawing chamber 12b and suppress the generation of frost, and discharges water vapor to the outside. By such an all-zone thawing operation, all foods in the cooling / thawing chamber 12b are thawed. The all-zone defrosting operation ends as in the zone defrosting operation. After that, it returns to normal operation.

The micro freezing operation is an operation executed when the food (thawed food) after thawing is left as it is without being taken out from the cooling / thawing chamber 12b.

Thawed foods thawed by the zone defrosting operation or all-zone defrosting operation are left as they are, and then frozen again by the normal operation thereafter. Therefore, the user may take out the thawed food from the freezing / thawing chamber 12b in a re-frozen state. Of course, the refrigerated state is so hard that the user cannot immediately cook the food. To cope with this, it is conceivable to maintain the temperature of the thawed food at a temperature at which it does not freeze after thawing, but in that case, the thawed food may be damaged if left unattended for a long time.

Therefore, in the case of the present embodiment, when the thawed food is left as it is without being taken out from the cooling / thawing chamber 12b, the thawed food is compared with the frozen storage temperature (-16 ° C to -20 ° C). High refrigeration storage temperature (maintaining at the second refrigeration storage temperature, for example, micro freezing operation that maintains the frozen food at a micro freezing temperature (for example, -3 ° C to -7 ° C) so that it is in a microfrozen state (second cooling storage The "micro-frozen state" here means a state in which the liquid outside the cells does not freeze, but the liquid outside the cells freezes.

Note that the contents of the micro freezing operation (zone micro freezing operation) performed after zone defrosting operation and the micro freezing operation (all zone micro freezing operation) performed after all zone defrosting operation are different.

After the zone thawing operation, the zone slight freezing operation is executed. This operation is an operation in which the temperature in the freezing / thawing chamber 12b is maintained at the freezing storage temperature and the defrosted food in the thawing zone DZ is heated by the heating unit 50 so that the temperature is maintained at the slight freezing temperature. . As a result, the thawed food in the thaw zone DZ is maintained at the fine freezing temperature, while the food in the non-thaw zone NDZ is maintained at the frozen storage temperature as in the normal operation.

After the all-zone defrosting operation, the all-zone defrosting operation is executed. This operation is an operation in which the temperature in the freezing / thawing chamber 12b is maintained at a slight freezing temperature while the heating unit 50 is stopped. As a result, the thawed food in the freezing / thawing chamber 12b is maintained at the slight freezing temperature.

In order to execute the zone and all-zones micro freezing operation, a defrosted food detection unit (heated food detection unit) that detects whether or not the defrosted food is present in the freezing / thawing chamber 12b after the defrosting is completed. is necessary.

In the case of the present embodiment, the presence of defrosted food is detected using the reflectance described above. That is, the reflected wave detection circuit 62 that detects the reflected wave and the control unit 30 that calculates the reflectance based on the detected reflected wave function as a defrosted food detection unit.

Specifically, as described in the quenching operation, when the food to be frozen is placed in the thawing zone DZ, the reflectance drops below the first threshold value R1. From the opposite point of view, when the thawed food product is taken out of the thaw zone DZ, the reflectance increases above the first threshold value R1. Therefore, if the reflectance rises above the first threshold R1, it can be determined that the defrosted food that has been thawed by the zone thaw operation has been taken out of the thaw zone DZ, or the thaw by the whole zone thaw operation. It can be determined that the processed food has been taken out from the thawing zone DZ and the non-thawing zone NDZ.

When the presence of thawed food is detected in the freezing / thawing room 12b after the end of thawing, the zone or all-zones micro freezing operation is executed. Normal operation is performed if the presence of food is not detected.

Alternatively, as shown in FIG. 3, the presence of the thawed food may be detected by the door sensor 34 that detects the opening / closing of the door of the cooling / thawing chamber 12b (the door portion 46b of the drawer 46).

The user needs to open the door to take out the thawed food from the freezing / thawing chamber 12b. Therefore, when the door sensor 34 does not detect the opening of the door after thawing, it can be determined that the thawed food is present in the freezing / thawing chamber 12b.

Further details of the zone micro-freezing operation and all-zone micro-freezing operation will be described using the flowchart shown in FIG.

As shown in FIG. 15, first, when the zone (all zones) defrosting operation is completed, the control unit 30 starts the zone (all zones) micro freezing operation in step S100.

In step S110, the control unit 30 determines whether or not food is present in the freezing / thawing chamber 12b. When it exists, it progresses to step S120. If not, the process proceeds to step S140.

In step S120, the control unit 30 determines whether or not the food item detected in step S110 is a thawed food item. This is because there is a possibility that the food detected in step S110 is a food that is stored in the freezing / thawing chamber 12b and then frozen. However, when the food detected in step S110 is a food to be frozen, the door of the freezing / thawing chamber 12b is opened by the user after the thawing is completed. That is, the door sensor 34 detects the opening of the door after the thawing is completed. Therefore, when the door sensor 34 does not detect the opening of the door, it is determined that the food item detected in step S110 is a defrosted food item, and the process proceeds to step S130. If not, it is determined that the food detected in step S110 is a food to be frozen, the process proceeds to step S160, the zone (all zones) micro freezing operation is ended, and the quenching operation is started in step S170. .

When it is determined in step S120 that the food has been thawed, the control unit 30 determines in step S130 whether a predetermined period has elapsed from the end of the thawing. This is because if the thawed food is stored in a slightly frozen state for a long period of time, the quality will deteriorate. In the case of the all-zone defrosting operation, the predetermined period is, for example, 7 days. In the zone defrosting operation, frost is more likely to occur than in the all-zone defrosting operation, so the predetermined period is 5 days, which is shorter than in the all-zone defrosting operation. When the predetermined period has passed from the end of the thawing, the process proceeds to step S140 to end the zone (all zones) micro freezing operation, and then the normal operation is started in step S150. If the predetermined period has not elapsed, the process returns to step S110.

As described above, according to the present embodiment, in a refrigerator having a freezing / thawing chamber capable of freezing and thawing food, it is possible to properly store the thawed food that is thawed in the freezing / thawing chamber and left as it is. You can

Although the present invention has been described with reference to the above embodiment, the present invention is not limited to the above embodiment.

For example, in the case of the above-described embodiment, as shown in FIG. 5, the cooling / thawing chamber 12b is divided into a thawing zone DZ and a non-thawing zone NDZ. That is, the oscillation electrode 52 and the counter electrode 54 are arranged to face each other with a part of the cooling / thawing chamber 12b interposed therebetween. However, the embodiment of the present invention is not limited to this. The oscillation electrode and the counter electrode may be arranged to face each other across the entire cooling / thawing chamber. That is, the entire cooling / thawing chamber may be a thawing zone in which food can be dielectrically heated and thawed.

Also, in the case of the above-described embodiment, the method of heating and thawing food is dielectric heating using the oscillation electrode and the counter electrode, but the embodiment of the present invention is not limited to this. For example, a sheathed heater may be used.

Furthermore, in the case of the above-mentioned embodiment, the end of the thawing of food is judged based on the reflectance. However, the embodiment of the present invention is not limited to this. For example, the user may set the thawing time, and the timing when the thawing time has elapsed from the start of the thawing may be the food thawing end timing. In this case, the operation unit is configured to be able to receive the defrosting start instruction from the user and input the defrosting time.

Furthermore, in the case of the above-described embodiment, as shown in FIG. 4, the accommodation chamber of the heating module 40 functions as a freezing / thawing chamber 12b capable of freezing and thawing by introducing cold air. However, the embodiment of the present invention is not limited to this. The heating module may not introduce cold air into its accommodation chamber, i.e. may be dedicated to thawing. The heating module 40 may be used not only for freezing and thawing, but also for cooling and heating food as a temperature control. That is, the accommodation chamber of the heating module 40 may be a cooling / heating chamber.

In addition, in the above embodiment, the description has been centered on the case of heating and thawing in the freezer compartment, but heating may be performed in a room in a temperature zone other than that in the refrigerator. For example, by heating milk containing yogurt bacteria or soybean containing natto bacteria stored in a refrigerator, it is possible to promote fermentation to make homemade yogurt or homemade natto.

Further, it is possible for a person skilled in the art to combine at least a part of one embodiment with another at least one embodiment as a whole or in part to form a further embodiment according to the present invention. Is obvious to

The embodiment has been described above as an example of the technology according to the present disclosure. To that end, the accompanying drawings and detailed description are provided. Therefore, among the constituent elements described in the accompanying drawings and the detailed description, not only constituent elements essential for solving the problem but also constituent elements not essential for solving the problem in order to exemplify the above-mentioned technology. Can also be included. Therefore, it should not be immediately recognized that the non-essential components are essential, because the non-essential components are described in the accompanying drawings and the detailed description.

Further, since the above-described embodiment is for exemplifying the technique in the present disclosure, various changes, replacements, additions, omissions, etc. can be made within the scope of the claims or the scope of equivalents thereof.

The disclosures of Japanese Patent Application No. 2018-199433, filed on October 23, 2018, drawings, and claims are incorporated herein by reference in their entirety. .

The present invention can be applied to a refrigerator having a heating function.

Claims (11)

1. A refrigerator having a cooling / heating chamber capable of cooling and heating food, comprising:
   A heating unit for heating the food by heating the cooling / heating chamber;
   After the heating of the food is finished, a heated food detection unit for detecting whether or not the heated food is present in the cooling / heating chamber,
   A refrigerator that changes a cooling temperature of a cooling operation of the cooling / heating chamber based on a detection result of the heated food detection unit.
2. The normal operation of maintaining the cooling temperature of the cooling operation of the cooling / heating chamber at the first cooling storage temperature is executed when the heated food detection unit does not detect the heated food. refrigerator.
3. When the heated food is detected by the heated food detection unit, the cooling temperature of the cooling operation of the cooling / heating chamber is maintained at the second cooling storage temperature higher than the first cooling storage temperature. The refrigerator according to claim 2, wherein the refrigerator performs a second cooling storage operation.
4. The refrigerator according to claim 3, wherein the second cooling operation is switched to the normal operation after a lapse of a predetermined time from the end of heating.
5. The cooling / heating chamber is divided into a heating zone, which is a space in which food to be heated is placed, and a non-heating zone, which is a space continuous with the heating zone and in which food to be non-heated is placed. ,
   The heating unit applies an AC voltage between the oscillation electrode and the counter electrode arranged to face each other with the heating zone of the cooling / heating chamber interposed therebetween, and applies an AC voltage between the oscillation electrode and the counter electrode. Including an oscillating section for heating the food of
   When the heated food is detected by the heated food detection unit, while maintaining the cooling / heating chamber at the first cooling storage temperature, by heating the heated food by the heating unit, The refrigerator according to any one of claims 1 to 4, wherein the heated food product is maintained at the second cooling storage temperature.
6. The heated food detection unit, a reflected wave detection unit that detects a reflected wave returning to the oscillation unit, and a reflectance calculation unit that calculates the reflectance that is the ratio of the reflected wave to the incident wave output from the oscillation unit. Including,
   The heated food detection unit, the reflectance is smaller than a first threshold value which is a value smaller than a value when the heated food is not present between the oscillation electrode and the counter electrode. The refrigerator according to claim 5, wherein the refrigerator detects the heated food when it is small.
7. A door for opening and closing the cooling / heating chamber,
   A door sensor for detecting opening and closing of the door,
   The refrigerator according to any one of claims 1 to 5, wherein the heated food detection unit detects the heated food when the door opening / closing sensor does not detect opening of the door after heating is completed.
8. While the food is being heated by the heating unit, when the reflectance rises and reaches a second threshold value which is a smaller value than the first threshold value, the oscillation electrode and the opposing surface are opposed to each other. It has a matching part for impedance matching with the electrodes,
   When the impedance matching does not decrease the reflectance beyond the third threshold value, which is smaller than the second threshold value, the impedance matching execution timing is the food heating end timing. The refrigerator according to claim 6.
9. Having an operation unit for the user to input a heating time while receiving a user's heating start instruction,
   The refrigerator according to any one of claims 1 to 6, wherein the timing when the heating time has elapsed from the timing when the start instruction is received is set as the heating end timing of the food.
10. The refrigerator according to any one of claims 2, 3, and 5, wherein the first cold storage temperature is a freezing temperature.
11. The refrigerator according to claim 3 or 5, wherein the second cooling storage temperature is a slight freezing temperature.

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