JPH03137481A - Refrigerator with defreezing chamber - Google Patents

Abstract

PURPOSE:To reduce an irregular defreezing operation and enable a defreezing state to be attained within a short period of time by a method wherein an far infra-red ray heater and a heating heater are continuously energized until a bottom plate is heated up to a predetermined temperature from a starting of defreezing operation and subsequently a rate of interruption of electrical energization is decreased in a stepwise manner. CONSTITUTION:A direct application of a far infra-red ray with a far infrared ray heater 34 and an indirect application through a reflecting plate 39 against an upper surface and side surfaces of a defreezed food 45 in a defreezing chamber 15 and a transmitted heating is carried out from a heating heater 42 at the bottom surface. Both heaters are continuously energized until a temperature sensor 43 at the bottom surface shows an increased predetermined temperature, and a temperature of the defreezed food 45 is rapidly increased. After that, a rate of intermittent electrical energization for both heaters is decreased in a stepwise manner. A cold air is uniformly supplied to the defreezed food 45 through several vent holes 40 formed in the reflection plate 39 under an operation of a damper thermo-element so as to restrict an increasing of temperature at the surface of the food. Upon completion of the defreezing operation, a temperature of the food is kept at a temperature range between a refrigeration temperature and a freezing temperature. With the foregoing, it is possible to perform a defreezing operation with a less amount of irregular temperature distribution within a short period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a refrigerator with a thawing chamber for thawing frozen foods.

2. Description of the Related Art Conventionally, it is known that a heater is used to thaw frozen foods. For example, the example shown in Japanese Patent Publication No. 48-25414 is sb, and will be explained below with reference to FIGS. 6 and 7.

1 is a thawing box; an outer box 2 formed into a box shape of metal or synthetic resin; and a metal such as aluminum with good thermal conductivity provided with an appropriate gap inside the outer box 2. It consists of an inner box 3 made of Reference numeral 4 denotes a linear heater, which is closely connected to the inner box 3 through aluminum foil 5 so that the bottom surface of the thawing box 1 is sparse and the top surface is densely packed. ,
6 is a heat insulating material interposed between the outer box 2 and the aluminum foil 6.

In this configuration, when the food 7 to be thawed is placed on the bottom of the thawing box 1 and the thawing action is started, heat is applied to the entire circumference of the inner box 3 by the heating of the heater 4, and the food is thawed almost uniformly. The feature is that the food 7 is heated and thawed.

Problem to be Solved by the Invention However, with such a configuration, heat is transmitted from the bottom of the thawing box 1 to the bottom of the food to be thawed 7 by thermal conduction. The effect of radiant heat on the food to be thawed 7 from the top and side surfaces of the thawing box 1 is almost negligible because the heat ray wavelength from the heater 4 through the inner box 3 is in the near-infrared region of 5 μm or less. Heating occurs only by heat transfer by convection of warmed air. Therefore, there are problems in that the food to be thawed 7 tends to be thawed unevenly between the center and the surface, and also takes a long time to thaw.
If food is left as it is after thawing, especially perishable foods such as fish meat, deterioration will occur due to the high ambient temperature, so the user must monitor the end of thawing and dispose of the food, so it cannot be used with confidence. There was a problem.

The present invention solves the above-mentioned problems, and aims to provide a thawing chamber, especially in a refrigerator, that is less uneven in thawing and can be thawed in a short time.

Means for Solving the Problems In order to solve the above problems, the refrigerator with a defrosting chamber of the present invention has the following features:
The thawing chamber has a configuration in which a far infrared heater and a reflector plate covering the upper part in a dome shape are provided on the upper surface of the thawing chamber, a bottom plate is provided with a heater and a temperature sensor in close contact with the bottom surface, and a thawing tray on which food to be thawed is placed is installed. do.

A ventilation passage is formed in the space on the back surface of the reflection plate to communicate with a damper thermometer for adjusting the amount of cold air inflow provided at the entrance of the thawing chamber, and a large number of ventilation holes are formed in the reflection plate. For such a configuration, during thawing, the damper thermo is forcibly opened and the blower is forced into operation, and the far-infrared heater and power heater are turned off from the start of thawing until the temperature of the temperature sensor on the bottom plate rises to the specified temperature. The heater is energized continuously, and thereafter both heaters are energized intermittently, and the intermittent energization rate is gradually reduced over time. A thawing control device is provided to maintain the temperature in the No. 3 temperature range.

Effects of the present invention With the above-described configuration, far-infrared rays are directly radiated by the far-infrared heater and indirectly radiated through the reflector from the top and side surfaces of the food to be thawed, and conductive heating is performed from the bottom heater. is carried out and heat is absorbed.

In addition, until the temperature sensor on the bottom rises to a predetermined temperature, both heaters are continuously energized and the temperature of the food to be thawed rises rapidly.After that, the intermittent energization rate to both heaters gradually decreases. Cold air is uniformly supplied to the food to be thawed through the many ventilation holes formed on the top surface of the deep radiation plate via the damper thermo, thereby suppressing the temperature rise on the food surface. Further, after thawing is completed, the temperature of the food is automatically maintained at a third temperature range between the refrigeration temperature and the freezing temperature by the temperature control function of the damper thermo, and the food is kept cold.

EXAMPLE A refrigerator with a defrosting chamber according to an example of the present invention will be described below with reference to FIGS. 1 to 6.

8 is the refrigerator itself and the outer box 9. Inner box 1o and both boxes 9,
It is composed of a heat insulating material 11 filled between 10 and 10.

12 is a partition wall that partitions the inside of the refrigerator main body 8 into upper and lower sections;
A freezing compartment 13 is provided in the upper part of the partition wall 12, and a refrigerator compartment 14 is provided in the lower part.
are divided into sections.

Reference numeral 16 denotes a thawing chamber provided in an upper section of the refrigerator compartment 14. 1e is a compressor of a refrigeration cycle provided at the rear of the bottom of the refrigerator main body 8, and 17 is a cooler housed in the back of the freezer compartment 13. 18 is a blower for forcing the cold air cooled by the cooler 17 into the freezing compartment 13, the refrigerator compartment 14, and the thawing compartment 15; 19.20 is the refrigerator compartment 1;
4. A damper thermometer is installed at the entrance of the thawing chamber 15 and adjusts the amount of cold air flowing in through electrical input.
To explain using damper thermo 2o for 5 as an example,
1 is an electromagnetic coil; 22 is a plunger that moves the inner core of the electromagnetic coil 21 up and down depending on the presence or absence of electromagnetic action; 23 is a rod connected to the plunger 22; 24 is a damper that opens and closes the cold air passage; carp 1v21
When energized, the rod 23 is pushed up by electromagnetic action to open the damper 24, and when the energization is cut off, the rod 23 falls downward and the damper 24 is closed. Although not shown in the drawings, for convenience of later explanation, the electromagnetic coil A/21' and the damper of the damper thermometer 19 for the refrigerating room having the same configuration will be referred to as 24'.

25 and 26 supply cold air from the blower 18 to the refrigerator compartment 1.
4. Discharge ducts 27 and 28 leading to the thawing chamber 16 are respectively connected to the refrigerating chamber 14. This is a suction duct for returning the cold air that has cooled the inside of the thawing chamber 15 to the cooler 17. Also, 29,30
．． 31 are the freezing chamber 13, the refrigerator chamber 14, and the thawing chamber 15, respectively.
This is a temperature sensor that detects the temperature inside the device.

Next, the detailed configuration of the defrosting chamber 15 will be explained.

32 is an outer box made of synthetic resin, and 33 is a heat insulating material installed on the inner surface of the outer box 32 to surround the outer periphery. 34 is the thawing chamber 1
This is a far infrared heater installed at the top of the heater wire 3.
A ceramic paint layer 37 containing silicon or the like as a main component is baked on the surface of a glass tube 36 in which a glass tube 36 is sealed to effectively emit far infrared rays of about 5 μm or more. This far infrared heater 34 is made of a holder 3 made of synthetic resin with high heat resistance.
It is suspended and supported through a dome-shaped reflector plate 39 made of metal such as aluminum. In addition, the reflector plate 39 is integrally formed with the inner box portions that constitute both side walls and the back wall of the thawing chamber 15, and furthermore, a large number of ventilation holes 4o are formed in the flat portions on both sides of the top dome portion. ing. Next, 41 is a bottom plate made of metal such as aluminum, 42 is a linear heater that is thermally conductively fixed to the back surface of the bottom plate 41 with AYV foil, etc., and 43 is a bottom plate made of metal such as aluminum. Face plate 41
This is a temperature sensor that is placed close to the center of the back surface for thermal conductivity. A thawing tray 44 is detachably installed on the bottom plate 41, and is composed of a tray 46 made of metal such as aluminum on which the food to be thawed 45 is placed, and a frame 47 made of synthetic resin surrounding the outer periphery. . Reference numeral 48 is a protective net for preventing burns that is fixedly installed below the reflecting plate 39 at a constant interval, and 49 is a door that opens and closes the front opening of the thawing chamber 15. Further, 5o is a ventilation passage formed in the space on the back surface of the reflector plate 39, and the damper thermometer 2 is connected through the discharge port 61.
Connected to 0. Reference numeral 62 denotes a suction port formed in the back wall of the thawing chamber 16, which communicates with the suction duct 28. 5
3 is a defrost switch provided on the front surface of the outer shell of the refrigerator main body 8.

Next, the electric circuit and control circuit will be explained.

The compressor 16 has a relay contact 64. The air blowers @8 are each connected to a power supply via a relay contact 55. The far-infrared heater 34 and the heater 42 are connected to a power source via a relay contact 56 and a relay contact 67, respectively. Also, the electromagnetic coil 21 of the damper thermo for the thawing chamber.
The electromagnetic coil 21' of the damper thermometer for the refrigerator compartment is connected to the power source via the four relay contacts 5859.

6o is a freezing room temperature control device, which includes a temperature sensor 29 such as a thermistor. A comparison circuit including resistors R4, R2, R3, a comparator e1, and a transistor 62. SuV-': 1417
63, the output of the comparator 61 is connected to the pace of the transistor 62. The collector of the transistor 62 is connected to the relay coil L'63 for attraction, which opens and closes the relay contact 64. 64 is a refrigerator room temperature control device, which includes a temperature detector 30 such as a thermistor, resistors R4, R5, R6, and a comparator 6.
Comparator circuit with transistor 66. A relay coil 67 is provided, and the output of the comparator 65 is connected to the base of the transistor 66. Further, the relay coil 67 for attraction is connected to the collector of the transistor 66\, which opens and closes the relay contact 59. 68 is a thawing chamber temperature control device, which includes a temperature detector 31 such as a thermistor, resistors R7, R8, R9, and a comparator 69.
a comparison circuit, an OR circuit 70, a transistor 71,
A relay coil/l/72 is provided, and the resistance is configured so that the temperature inside the thawing chamber 15 is controlled to a partial freezing temperature of about -3° C. during normal cooling. The output of the comparator 69 is connected to one input of the OR circuit 70. Further, the output of the OR circuit 70 is connected to the base of the transistor 71, and the collector of the transistor 71 is connected to the relay coil A/72 for attraction, which opens and closes the relay contact 68.

3 is a thawing control device, a temperature sensor 43 closely attached to the bottom plate 41 of the thawing chamber 15, and a resistor R1°.

R11, R12, a comparison circuit with a comparator 74 and a timer 75, 76, 77, an AND circuit 78°y9,
It is provided with OR circuits 8o, al, a2, the 0R11 path γo1 inverter 83, transistors 84, 85°86, relay coil/I/87, 88, 89, and the defrosting switch 63.

The outlet of the defrosting switch 53 is connected to the timer 7.
The output of the timer 75 is connected to one input of each of the AND circuits 7B and 79 and the OR circuits 70 and 82. The output of the comparator 74 is sent to the AND circuit 78 via the inverter 83.
At the same time, it is connected to the other input of the AND circuit 79. The output of the AND circuit 78 is connected to one of the OR circuits 80.81, and the output of the AND circuit 79 is connected to the timer 76.81.
77 input. and the timer 78
．． The outputs of 77 are connected to the other inputs of the OR circuits 80.81, and the outputs of the OR circuits 80.81 are connected to the bases of the transistors 84.85, respectively.

The collector of the transistor 84.85 is provided with the relay coil/coil for attraction that opens and closes the relay contact 56.57.
L'87.88 are connected. The other input of the OR circuit 82 is connected to the freezer compartment temperature control device 60.
The output of the comparator 61 is connected to the OR
The output of circuit 82 is connected to the base of transistor 86. An attraction relay coil 89 for opening and closing the relay contact 65 is connected to the collector of the transistor 86.

Here, the timer 76 has one input and “Hiqh”.
When a ``H'' signal (hereinafter referred to simply as ``H'') is input, the ``H'' signal continues to be output for a predetermined period of time, and then a ``Low'' (
The timers 76 and 77 switch to the ``H'' and ``nL'' signals for a predetermined period of time while the ``H'' signal is being input to the input. Although the signals are output alternately, the intermittent output rate of the "H" signal is gradually decreased as a predetermined period of time elapses.For example, specifically, the output of the timer 76 is high for the first time t1. ``Signal output rate is 80ch, next time t2
In this case, the configuration is such that the output rate of the "H" signal is 4 degrees,
The output of the timer 77 is configured such that the "H" signal output rate is 80% at the first time t1' and 01 at the next eclipse 2'. The operating time of the timer 76°77 is t1+t2=th1'+t
h2', and the predetermined time t of the timer 76 is the operating time t1+ of the timer 76.7, including the time-safe role of the defrosting action.
It is set to be sufficiently long as t2=t1'+t2'.

In this configuration, when the temperature of the freezer compartment 13 is higher than a predetermined value, the resistance value of the temperature detector 29 becomes small and the output of the comparator 61 becomes "H", so that the transistor 62 becomes ONI, and the relay coil/ v63 becomes conductive. Therefore, the relay contact 64 is closed and the compressor 1e is operated. At the same time, the output of the OR circuit 82 is also 'H', so the transistor 8e is turned on and the relay coil 89 is made conductive.Therefore, the relay contact 55 is closed and the blower 18 is also operated, causing the freezer compartment to open. 13. Cold air is forced into the refrigerator compartment 14 and thawing compartment 15 for cooling.

Thereafter, when the freezer compartment 13 is cooled to a predetermined temperature, the resistance value of the temperature detector 29 increases and the output of the comparator 6 becomes nL''.Therefore, the transistor 2 is turned off.
However, since the output of the OR circuit 82 also becomes "L", the transistor 86 is also turned off, and the current to the relay coil Al63.89 is cut off. Therefore, relay contacts 54 and 55 are both opened and compressor 16. The blower 18 stops. Thereafter, this action is repeated until the inside of the freezer compartment 13 reaches a predetermined temperature (for example, -2
temperature control is maintained at ob).

Next, when the temperature of the refrigerator compartment 14 is higher than the predetermined value, the resistance value of the temperature detector 3o becomes small and the comparator 6
5 becomes H", the transistor 66 turns on and the relay coil/L/67 becomes conductive. Therefore, the relay contact 59 is closed and the electromagnetic coil 21' is energized, and the damper 24' of the damper thermometer 19 is turned on. is opened and the refrigerator compartment 14
Cold air is introduced inside to perform a cooling effect. Thereafter, when the refrigerator compartment 14 is cooled to a predetermined temperature, the resistance value of the temperature detector 30 becomes large and the output of the comparator 66 becomes L''. Therefore, the transistor 6e becomes 0FFL.

The current to the relay coil A/1/67 is cut off, the relay contact 69 is opened, and the current to the electromagnetic coil A/21' is also cut off.

Then, the damper 24' of the damper thermostat 19 is closed to prevent cold air from flowing into the refrigerator compartment 14. Thereafter, this action is repeated until the inside of the refrigerator compartment 14 reaches a predetermined temperature (for example, 5
The temperature is maintained at ℃).

In addition, when the temperature of the thawing chamber 15 is higher than the predetermined value when not defrosting, the resistance value of the temperature detector 31 is small and the output of the comparator 69 becomes "H", so that the output of the OR circuit 70 becomes "H". At "H", the transistor transistor 1 turns ON and the relay coil 72 becomes conductive.Therefore, the relay contact 58 closes, the electromagnetic coil /l/21 is energized, and the damper 24 of the damper thermostat 20 is opened. The cold air is introduced into the thawing chamber 15 to perform a cooling effect.Then, the thawing chamber 1
5 is cooled to a predetermined temperature, the resistance value of the temperature sensor 31 increases and the output of the comparator 69 becomes 'L'. Therefore, the output of the OR circuit 70 becomes 'L' and the transistor 71 becomes OFF, the power to the relay coil/I/72 is cut off, the relay contact 58 is opened, and the electromagnetic coil/I/72 is turned off.
The power to /21 is also cut off.

The damper 24 of the damper thermostat 20 is then closed to prevent cold air from flowing into the thawing chamber 16.

Thereafter, by repeating this action, the interior of the thawing chamber 15 reaches the third temperature between the freezing temperature and the refrigeration temperature suitable for preserving fresh foods, as described above.
The temperature is maintained within a temperature range of approximately -3°C, that is, a partial freezing temperature range.

Next, we will discuss the action during thawing. First, the food to be thawed 45 to be thawed is placed on the thawing tray 44 and placed on the bottom plate 41 in the thawing chamber 15, and then the thawing switch 6 is turned on.
Insert 3. At the same time as the input, the timer 76 starts outputting a 'H' signal, and one input of the AND circuits 78 and 79 becomes 'H'. At this time, the temperature of the bottom plate 41 of the thawing chamber 15 decreases due to heat conduction with the thawing tray 44 on which the frozen food 46 having a low temperature (for example, -20° C.) is placed.

That is, the temperature sensor 43 is in a sufficiently low temperature state. Therefore, the output of the comparator 74 becomes "L".
The signal inverted to "H" by the inverter 83 is output to the AND circuit 7.
The other input of 8 is input. On the other hand, the signal I L jl without passing through the inverter 83 is input to the AND circuit 79 as it is. Therefore, the output of the AND circuit 78 is “H”
, the output of the AND circuit 79 becomes L'', so the timer 7
6. T7 does not operate and the output of OR circuit 80.81 is “H”.
” and transistors 84.85 turn on.Then, relay coil 1V87.BB is energized, and relay contact 50
．． 57 is opened and the far infrared heater 34 and the heating heater 42
is continuously energized.

When the thawing action progresses and the temperature sensor 43 rises to a predetermined temperature (for example, 30 tE) (the time required for this is t), the output of the comparator 4 becomes H", and the inverter 83 is turned on. The L” signal is connected to A
It is input to the ND circuit 78 and the output of the AND circuit 78 becomes 'L.
On the other hand, since the 'H' signal is input to the AND circuit 79, the AND circuits 76 and 77 alternately repeat and output 'H' and 'L' signals at a predetermined intermittent rate.For this reason, OR circuit 80.81 with intermittent output rate accordingly
The transistors 84 and 8S are turned 0N10FF through the transistors 84 and 8S.

Then, the power supply to the relay coil μ87°88 is interrupted, and the relay contacts 56 and 57 are intermittently opened and closed. As a result, the far infrared heater 34 is continuously energized for the period t. At the time t1 that follows, the energization rate is 80%, and at the next time t2, the energization rate is 40%.
The heat generation capacity is controlled to decrease gradually over time. Further, the heater 42 is controlled in the above-mentioned manner. In this way, in the early stage of thawing when the temperature of the food 45 to be thawed is low, both the far-infrared heater 34 and the heater 42 are continuously energized until the temperature of the temperature sensor 43 rises to a predetermined temperature. Even if the weight of the food changes in different ways, depending on the degree of temperature rise in the temperature sensor 43, thawing will proceed rapidly under conditions with a large amount of heat generation for a time appropriate for each weight. Time can be shortened. Thereafter, the heat generation capacity gradually decreases with the passage of time, and thawing proceeds while suppressing the rise in surface temperature of the food to be thawed 46.

During thawing, radiant heating from the far-infrared heater 34 from the top surface of the food 46 to be thawed is performed evenly in conjunction with the reflection action of the reflector plate 39, and conductive heating by the heater 42 is simultaneously performed from the bottom surface. It turns out. here,
During heating by the far-infrared heater 34, far-infrared rays with a long wavelength of 5 μm or more are radiated to the food to be thawed 46, so that far-infrared rays are efficiently emitted from common foods that have an absorption wavelength band in the far-infrared wavelength region. It is absorbed and penetrates relatively far into the interior of the food to be thawed 45, and thawing proceeds in a state where the temperature unevenness between the surface and the center does not become relatively large. Further, in heating by the heater 42, the bottom portion of the food to be thawed 45, which cannot be sufficiently heated by the far-infrared heater 34, can be thawed by heat conduction heating via the thawing plate 44.

On the other hand, these far infrared heaters 34. Simultaneously with the heating action by the heater 42, during defrosting, that is, while the output of the timer 75 continues to generate the "H" signal, the output of the ○R circuit 70.82 also becomes "H" υ, and the transistor 71.89 turns ON.
Relay coil 2, 89 becomes conductive. Therefore, the relay contacts 58 and 55 are closed, and the electromagnetic coil 21 is energized regardless of the output of the thawing chamber temperature control device 68, and the damper 24 of the damper thermometer 2o for the thawing chamber is forcibly opened. The blower 18 is forcibly operated regardless of the output of the freezer compartment temperature control bag @60. Cold air forced through the damper 24 by the blower 18 is passed through the discharge duct 26 to the discharge port 51 of the thawing chamber 16.
It flows into the ventilation passage 60 in the inner upper part. The cold air that has flowed into the ventilation path 50 is discharged downward through a large number of ventilation holes formed in the reflection plate 39, thereby uniformly cooling the surface of the food to be thawed 45.

Due to this action, the food to be thawed 45 is mainly affected by the far-infrared radiation effect of the far-infrared heater 34 and the far-infrared radiation effect of the far-infrared heater 34.
In addition to the control effect of gradually reducing the heat generation capacity of the heater 42, the temperature rise at the surface area is further suppressed, and as a result, the temperature difference between the center area and the surface area is small, resulting in uneven thawing. A small amount of thawing can be realized (the temperature characteristics and time chart of the food 45 to be thawed during thawing are shown in FIG. 6).

Regarding the thawing time, due to the internal penetration effect of far infrared rays and continuous heating control in the early stage of thawing, it is possible to thaw in a relatively short time, for example, a tuna with a weight of 5 oop and a thickness of 25 mm is about 3 omi.
), and since the reflector plate 39 is exposed in the ventilation path 5o, the temperature of the reflector plate 39 itself and surrounding members, which would otherwise be at a fairly high temperature, is cooled and lowered, which is advantageous in terms of safety. The cold air that has flowed into the thawing chamber 15 is collected into the cooler 17 through the suction tally 28 from the suction port 52 opened at the rear surface after the cooling effect.

As this thawing action progresses, time t0+t1+t2=
When t0+t1'+t2' elapses, timer 76.7
At the same time, the output of the timer 76 becomes 6L'', which is input to the reset terminal of the timer 76, and the output of the timer 76 also becomes ``L''. Therefore, the transistor 84.8
5 are respectively 0FFI, te relay carp/l/87, 8JEl
The relay contacts 56 and 67 are opened, and the far-infrared heater 34 and the heater 42 are de-energized and thawing is completed. At the same time, OR circuit 70.82
Since one of the inputs becomes L'', the forced operation state of the blower 18 and the forced open state of the damper 24 of the thawing chamber damper thermometer 2Q are canceled.

After thawing, the temperature sensor 3
The temperature inside the defrosting chamber 15 is controlled based on the detected temperature. Therefore, the food to be thawed 45 after thawing is immediately cooled to be stable in the partial freezing temperature range of about -3°C, and the temperature does not rise further due to residual heat. Even if you leave it as it is after thawing, it is kept cool at a partial freezing temperature range of approximately -3°C, which is suitable for preserving fish and meat sketches, so the user does not have to monitor the completion of thawing as usual. Thawing can be carried out safely without the need for immediate processing, and the food to be thawed 45 can be used at any time after thawing, making it extremely convenient to use.

Effects of the Invention As described above, the refrigerator with a defrosting chamber of the present invention provides the following effects.

(1) Efficient heating can be achieved from both sides: far-infrared radiant heating with the far-infrared heater on the top side, and thermal conduction heating with the heater on the bottom side, and the heat generation capacity of both heaters gradually decreases during thawing. In combination with this and the effect of far infrared rays penetrating into the inside of the food to be thawed, thawing with less temperature unevenness between the center and the surface becomes possible.

(2) Since the far-infrared heater and heating heater are continuously energized until the temperature sensor installed on the bottom plate of the thawing chamber rises to a predetermined temperature, even if the weight of the food to be thawed changes, the maximum time is suitable for each. A high-capacity heater allows for rapid heating and thawing in a short time.

(3) During thawing, the damper thermo for the thawing chamber is forcibly opened, and the blower is forced to operate continuously, allowing cold air to descend and flow into the food to be thawed through the ventilation passage formed in the space on the back of the reflector. As a result, the surface of the food to be thawed is evenly cooled, temperature rise is further suppressed, and thawing with less unevenness can be achieved.

(4) During thawing, the reflector and the surrounding parts of the pond, which normally become high in temperature, are exposed to the ventilation path and cooled, so the temperature decreases, which is advantageous from a safety perspective.

(5) After thawing, the inside of the thawing chamber is kept cool in the third temperature range between the freezing room temperature and the refrigerator room temperature (for example, the partial freezing temperature range of approximately -3°C), so it is exposed to residual heat immediately after thawing. The temperature of the thawed food does not rise further, and even if it is left as is, its freshness is maintained at a temperature suitable for raw food such as fish meat, and the food can be used at any time.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a refrigerator with a defrosting chamber showing an embodiment of the present invention, FIG. 2 is a cross-sectional view of the defrosting chamber in FIG. A longitudinal sectional view of a refrigerator with a thawing chamber, FIG. 4 is an enlarged sectional view of the damper thermometer installed at the entrance of the thawing chamber shown in FIG. 1, and FIG. 5 is a refrigerator with a thawing chamber shown in FIG. 3. Fig. 6 is a time chart during thawing and a temperature characteristic diagram of the food to be thawed, Fig. 7 is a perspective view of a conventional thawing box, and Fig. 8 is a diagram of the defrosting box shown in Fig. 7. It is a sectional view taken along the line B-B' of the box. 13... Freezer room, 14... Refrigerator room, 1
5. Old... Thawing chamber, 1θ... Compressor, 1...
...Cooler, 18...il[,20...
... Damper thermo, 34 ... Far infrared heater, 39 ... Reflection plate, 4o ... Ventilation hole, 41 ... Bottom plate, 42 ... ... Heater, 43 ... Temperature detector, 44 ... Thawing dish, 45 ... Food to be thawed, 49 ...
Door, 50... Ventilation path, 73... Thawing control device.

Claims (1)

[Claims] A freezing room, a thawing room whose outer periphery is surrounded by a heat insulating material, and a door that can be opened and closed at the front opening, a refrigeration cycle compressor, a cooler, and the air cooled by the cooler is transferred to the freezer. a blower for forcing air into the storage compartment, refrigerator compartment, and thawing compartment; a far-infrared heater provided at the top of the thawing compartment; a heating heater that is thermally conductively attached to the back surface of the metal bottom plate; A temperature sensor that is thermally conductively attached to the approximate center of the back surface, a metal reflector that covers the top surface of the far-infrared heater in a dome shape, and a thermally conductive sensor on which the food to be thawed is placed and placed on the bottom plate. A thawing tray that is installed in a removable manner, and a damper thermo that is installed at the entrance of the thawing chamber and adjusts the amount of cold air flowing in through electrical input, communicates with the damper thermo and is formed in the space above the back surface of the reflector. and a large number of ventilation holes provided on the reflector plate to communicate the ventilation passages with the inside of the thawing chamber. The far-infrared heater and the heating heater are continuously energized for the time until the temperature of the detector rises to a predetermined temperature, and after that, the energization is intermittently applied to both heaters, and the energization is performed intermittently in stages as time passes. 1. A refrigerator with a thawing chamber, comprising a thawing control device that lowers the rate of defrosting and maintains the thawing chamber in a third temperature range between the refrigerating temperature and the freezing temperature when not thawing.