JP2763622B2 - Refrigerator with thawing room - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a refrigerator with a thawing compartment for thawing frozen food.

2. Description of the Related Art Conventionally, an example in which a heater is used for thawing frozen food is known. An example is disclosed in Japanese Patent Publication No. 48-25414, which will be described below with reference to FIGS. 7 and 8.

Reference numeral 1 denotes a thawing box, which is an outer box 2 formed of a metal or a synthetic resin or the like in a box shape, and a metal such as aluminum having good thermal conductivity provided with an appropriate gap in the inner box of the outer box 2. The inner box 3 is made of steel. Numeral 4 denotes a linear heater, which is thermally conductively and tightly connected to the inner box 3 by aluminum foil 5 so that the bottom surface of the thawing box 1 is sparse and the upper surface is dense. Reference numeral 6 denotes a step heating material interposed between the outer box 2 and the aluminum box 5.

In such a configuration, the non-thawed food 7 is placed on the bottom of the thaw box 1.
When the thawing action is started by placing the garbage, the heat is applied from the entire circumference of the inner box 3 by the heating of the heater 4, and the thawing target food 7 is heated almost uniformly, and the thawing is performed. I have.

However, in such a configuration, from the bottom of the thawing box 1,
Although heat is transferred to the bottom surface of the food 7 to be thawed by heat conduction and the fixed surface portion can be thawed, the effect of radiant heat from the top surface and the side surface of the defrosting box 1 to the food 7 to be thawed is as follows.
Since the heat ray wavelength through the inner box 3 is in the near-infrared region of 5 μm or less, there is almost no heating, and heating is performed only by heat transfer by convection of the heated air in the thawing box 1. Therefore, the thawing unevenness between the central part and the surface part of the food 7 to be thawed tends to be large, and the thawing time is long. In this case, since the deterioration occurs due to the high ambient temperature, it is necessary for the user to monitor and process the end of the thawing, and there is a drawback that the thawing cannot be performed with a sense of security.

An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a thawing chamber which can reduce thawing unevenness and can be thawed in a short time, especially in a refrigerator.

Means for Solving the Problems In order to solve the above-mentioned problems, a refrigerator with a thawing room according to the present invention comprises a far-infrared heater on the upper surface of the thawing room, a reflector covering the upper part in a dome shape, a heater and a temperature detector on the bottom surface. Is provided, and a thawing dish on which the food to be thawed is placed is placed on the bottom plate. Then, a ventilation path is formed in the backside space after reflection, and the ventilation path is communicated with a damper thermostat for adjusting the amount of cool air inflow provided at the inlet of cool air in the thawing chamber, and a number of ventilation holes are formed in the reflector. For such a configuration, the blower is forcibly operated during the thawing, and the far-infrared heater, as the first stage, from the start of the thawing until the temperature of the temperature detector on the bottom plate rises to a predetermined temperature.
The heaters are continuously energized, and thereafter, the heaters are intermittently energized to a second stage and a third stage, so that the intermittent energization rate is reduced in a stepwise manner. A thawing control device is provided for forcibly opening the thermostat, forcibly closing the thermostat in the third stage, and for maintaining the thawing chamber in a third temperature zone between the refrigeration temperature and the freezing temperature when not thawing.

Effect of the Invention According to the above-described configuration, the present invention performs direct radiation of far-infrared rays from the top and side surfaces of the food to be thawed by the far-infrared heater and indirect radiation through the reflector plate, and performs heat transfer heating from the bottom heater. Is absorbed. Further, in the first stage in which the temperature detector on the bottom surface rises to a predetermined temperature, both heaters are continuously energized, and the temperature of the food to be thawed rises sharply.
In the third step, the temperature gradually decreases. In the first and second steps, the cold air is uniformly supplied to the food to be thawed from the many ventilation holes formed on the upper surface of the reflector through the damper thermostat. Suppress surface temperature rise. Then, in the third stage, the damper thermostat is closed and the exhaust heat in the thawing chamber is not recovered to the cooler side. Further, after the thawing is completed, the food temperature is automatically kept at a third temperature zone between the refrigeration temperature and the freezing temperature and kept cool by the temperature control action of the damper thermostat.

Embodiment 1 The following is a first embodiment of a refrigerator with a thawing room according to one embodiment of the present invention.
A description will be given with reference to FIGS.

Reference numeral 8 denotes a refrigerator body, an outer box 9, an inner box 10, and both boxes 9,10.
It is composed of a heat insulating material 11 filled in between. Reference numeral 12 denotes a partition wall for partitioning the inside of the refrigerator main body 8 up and down. A freezing compartment 13 is formed above the partition wall 12, and a refrigerator compartment 14 is formed below the partition wall. Reference numeral 15 denotes a thawing chamber provided in an upper section of the refrigerator compartment 14. Reference numeral 16 denotes a compressor of a refrigeration cycle provided at the rear of the bottom of the refrigerator body 8, and reference numeral 17 denotes a cooler housed in the back of the freezing compartment 13. Reference numeral 18 denotes a blower for forcibly ventilating the cool air cooled by the cooler 17 into the freezing compartment 13, the refrigeration compartment 14, and the thawing compartment 15, and 19 and 20 are provided at the inlets of the refrigeration compartment 14, the thawing compartment 15. This is a damper thermostat that adjusts the inflow of cold air by electrical input.
For example, 21 is an electromagnetic coil, 22 is a plunger that moves up and down the inner core of the electromagnetic coil 21 depending on the presence or absence of an electromagnetic action, 23 is a rod joined to the plunger 22, and 24 opens and closes a cool air passage. When the power is supplied to the electromagnetic coil 21, the rod 23 is pushed up by electromagnetic action to open the damper 24, and when the power is cut off, the rod 23 falls downward and the damper 24 is closed. It is configured to do so. Although not shown, for convenience of the following description, the electromagnetic coils of the damper thermometer 19 for the refrigerator having the same configuration are denoted by 21 'and damper 24'.

25, 26 is a discharge duct that guides cool air from the blower 18 to the refrigeration compartment 14 and the thawing compartment 15, 27 and 28 are the refrigeration compartment 14,
This is a suction duct for returning the cool air that has cooled the inside of the thawing chamber 15 to the cooler 17. 29, 30, 31 are the freezer compartments 13,
This is a temperature detector that detects the temperature inside the refrigerator compartment 14 and the thawing compartment 15.

 Next, a detailed configuration of the thawing chamber 15 will be described.

Reference numeral 32 denotes an outer box made of a synthetic resin, and reference numeral 33 denotes a heat insulating material provided on the inner surface of the outer box 32 and surrounding the outer periphery. Numeral 34 denotes a far-infrared heater provided in the upper part of the thawing chamber 15. The surface of a glass tube 36 enclosing the heater wire 35 is baked and coated with a ceramic paint layer 37 containing silicon or the like as a main component, and a far-infrared heater of about 5 μm or more is applied. It is configured to emit infrared rays effectively. The far-infrared heater 34 is supported by a dome-shaped reflection plate 39 made of metal such as aluminum via a holder 38 made of synthetic resin having high heat resistance. The reflection plate 39 is also formed by integrally forming both side walls in the thawing chamber 15 and an inner box portion forming the back wall, and furthermore, a large number of ventilation holes 40 are formed in a flat portion 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 aluminum foil or the like, and 43 is a bottom heater of the bottom plate 41. This is a temperature detector that is in close contact with the center of the back surface in a thermally conductive manner. Reference numeral 44 denotes a thawing plate which is detachably mounted on the bottom plate 41, and a metal plate 46 made of metal such as aluminum on which a food 45 to be thawed is placed and a frame 47 made of a synthetic resin surrounding the outer periphery.
It consists of. Reference numeral 48 denotes a protective net for preventing burns fixed at a predetermined interval below the reflector 39.
Is a door that opens and closes the front opening of the thawing chamber 15. Also, 50
Is a ventilation path formed in the back surface space of the reflection plate 39, and communicates with the damper thermo 20 through a discharge port 51. 52
Is a suction port formed in the inner wall of the thawing chamber 15 and communicates with the suction duct. Reference numeral 53 denotes a defrosting switch provided on the front surface of the outer shell of the refrigerator body 8.

Next, an electric circuit and a control circuit will be described. Compressor
16 is connected to a power supply via a relay contact 54, and the blower 18 is connected to a power supply via a relay contact 55. The far-infrared heater 34 is connected to a power supply via a relay contact 56, and the heater 42 is connected to a power supply via a relay contact 57. Further, the electromagnetic coil 21 of the damper thermometer for the thawing room and the electromagnetic coil 21 'of the damper thermometer for the refrigerator compartment are connected to the power supply via relay contacts 58 and 59, respectively.

Reference numeral 60 denotes a freezing room temperature control device, which includes a temperature detector 29 such as a thermistor, resistors R ₁ , R ₂ , R ₃ , a comparison circuit including a comparator 61, a transistor 62, and a relay coil 63. The output is connected to the base of the transistor 62. The collector coil of the transistor 62 is connected to the attraction relay coil 63 for opening and closing the relay contact 54. Reference numeral 64 denotes a refrigerator temperature control device, a temperature detector 30 such as a thermistor, a resistor R ₄ , R ₅ , R ₆ , a comparison circuit including a comparator 65, a transistor 66, and a relay coil.
The output of the comparator 65 is connected to the base of the transistor 66. The collector of the transistor 66 is connected to the attraction relay coil 67 for opening and closing the relay contact 59. Reference numeral 68 denotes a thawing room temperature controller, which includes a temperature detector 31 such as a thermistor and a resistance.
_{R 7, R 8, R 9} , comparing circuit, OR circuit 7 which includes a comparator 69
0, an AND circuit 70a, a transistor 71, and a relay coil 72. During normal cooling, the temperature of the thawing chamber 15 is about -3 ° C.
The resistance is configured so that the temperature is controlled to the partial freezing temperature. The output of the comparator 69 is the OR circuit
Connected to one input of 70. The output of the OR circuit 70 is connected to the base of the transistor 71 via the AND circuit 70a. The collector of the transistor 71 is connected to the attraction relay coil 72 for opening and closing the relay contact 58.

Reference numeral 73 denotes a thawing control device, which is a temperature detector 43 closely attached to the bottom plate 41 of the thawing chamber 15, resistors R ₁₀ , R ₁₁ , R ₁₂ , and a comparator 7.
Comparison circuit with 4 and timers 75, 76, 77, 77a, AND circuit 7
8, 79, OR circuits 80, 81, 82, the OR circuit 70, the inverter 83,
It includes transistors 84, 85, 86, relay coils 87, 88, 89 and the decompression switch 53.

The outlet of the thawing switch 53 is connected to the timer 75.
The output of the timer 75 is connected to the AN
D circuits 78 and 79 and OR circuits 70 and 82 are respectively connected to one input. The output of the comparator 74 is
Is connected to the other input of the AND circuit 78 at the same time as the other input of the AND circuit 79. The output of the AND circuit 78 is connected to one of the OR circuits 80 and 81, and the output of the AND circuit 79 is connected to the timers 76 and 7.
Connected to the input of 7,77a. And the timer 76,
The output of 77 is connected to the other input of each of the OR circuits 80 and 81, and the output of the OR circuits 80 and 81 is connected to the bases of the transistors 84 and 85, respectively. The collector coils of the transistors 84 and 85 are connected to the attraction relay coils 87 and 88 for opening and closing the relay contacts 56 and 57. The output of the timer 77a is connected to one input of the AND circuit 70a together with the output of the OR circuit 70. The other input of the OR circuit 82 is connected to the output of the comparator 61 of the freezing room temperature control device 60, and the output of the OR circuit 82 is connected to the base of the transistor 86. The collector of the transistor 86 is connected to a relay coil 89 for attraction for opening and closing the relay contact 55.

Here, once the signal of “High” (hereinafter simply referred to as “H”) is input to the input of the timer 75, the timer 75 sets “H” for a predetermined time t.
The signal is continuously output, and thereafter, the signal is switched to a signal of “Low” (hereinafter simply referred to as “L”). The timers 76 and 77 alternately output “H” and “L” signals for a predetermined time while the “H” signal is being input to the input, but after a predetermined time, the “H” signal is intermittently output. The output rate is configured to decrease gradually. For example, specifically, the output of the timer 76, the first time t ₁ is output rate of "H" signal 80
%, Is configured to output rate of the next signal in the time t ₂ at "H" of 40%, the output of timer 77 is a first time t ₁ 'is "H" output rate of the signal is 80%, the following At time t ₂ ′, the output rate of the “H” signal is set to 0%. The operation time of the timers 76 and 77 is configured to be t ₁ + t ₂ = t ₁ ′ + t ₂ ′. The predetermined time t of the timer 75 includes a time-safe function of the decompression operation. The operation time of the timers 76 and 77 is set to be sufficiently longer than t ₁ + t ₂ = t ₁ ′ + t ₂ ′. Further, the timer 77a is usually the output is "H", once continue "H" is between the output of the input time _{t 1 = t 1 '"H} " to the input, then the time t ₂ =
The output is set to “L” during t ₂ ′.

In such a configuration, when the temperature of the freezing 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 is turned on.
Turns on and relay coil 63 conducts. For this reason relay contacts
54 is closed and the compressor 16 is operated. Also at the same time
Since the output of the OR circuit 82 is also “H”, the transistor 86
Turns ON and the relay coil 89 conducts. For this reason, the relay contact 55 is closed, the blower 18 is also operated, and the freezing room 13 and the refrigeration room
14. Cooling is performed by forcing cool air into the thawing chamber 15. After that, if the freezing compartment 13 is cooled to a predetermined temperature, the temperature detector
The resistance value of the resistor 29 increases, and the output of the comparator 6 becomes “L”. Therefore, the transistor 62 is turned off, and the OR circuit 82
Is also "L", the transistor 86 is also turned off, and the power supply to the relay coils 63 and 89 is cut off. Therefore, the relay contacts 54 and 55 are both opened, and the compressor 16 and the blower 18 are stopped. Thereafter, this operation is repeated, and the inside of the freezing compartment 13 is maintained at a predetermined temperature (for example, −20 ° C.).

Next, when the temperature of the refrigerator compartment 14 is higher than a predetermined value, the resistance value of the temperature detector 30 becomes small, and the output of the comparator 65 becomes “H”, so that the transistor 66 is turned on and the relay coil 67 is turned on. I do. For this reason, the relay contact 59 is closed, the electromagnetic coil 21 is energized, and the damper
24 'is opened and cool air is introduced into the refrigerator compartment 14 to perform a cooling action. Thereafter, when the refrigerator compartment 14 is cooled to a predetermined temperature, the resistance value of the temperature detector 30 increases and the
The output of 65 becomes “L”. For this reason, the transistor 66
F, the power to the relay coil 67 is cut off and the relay contact 59
Is released, and the power supply to the electromagnetic coil 21 'is also cut off. Then, the damper 24 'of the damper thermo 19 is closed and the refrigerator compartment 14 is closed.
Cooling air is prevented from flowing into the inside. Thereafter, this operation is repeated to maintain the temperature inside the refrigerator compartment 14 at a predetermined temperature (for example, 5 ° C.).

When the temperature of the thawing chamber 15 is higher than a predetermined value at the time of non-thawing, the resistance value of the temperature detector 31 is small and the output of the comparator 69 becomes “H”, so that the OR circuits 70 and A
The output of the ND circuit 70a becomes "H", the transistor 71 turns on, and the relay coil 72 conducts. Therefore, the relay contact 58 is closed, the electromagnetic coil 21 is energized, the damper 24 of the damper thermo 20 is opened, and cool air is introduced into the thawing chamber 15 to perform a cooling action. Thereafter, when the thawing chamber 15 is cooled to a predetermined temperature, the resistance value of the temperature detector 31 increases, and the output of the comparator 69 becomes “L”. As a result, the output of the OR circuit 70 becomes “L”, the output of the AND circuit 70 a also becomes “L”, the transistor 71 is turned off, the power supply to the relay coil 72 is cut off, the relay contact 58 is opened, and the electromagnetic coil Power to 21 is also cut off. Then, the damper thermo 24 of the damper thermo 20 is closed to prevent the cool air from flowing into the thawing chamber 15. Thereafter, this operation is repeated, and the inside of the thawing chamber 15 is in the third temperature zone between the freezing temperature and the refrigeration temperature suitable for storing the produced food as described above,
That is, the temperature is maintained at a partial freezing temperature zone of about -3 ° C.

Next, the operation at the time of thawing will be described. First, place the food 45 to be thawed on the thawing tray 44 and place it in the thawing room.
After setting on the bottom plate 41 in 15, the thaw switch 53 is turned on. At the same time as the input, the timer 75 starts outputting the “H” signal, and one of the inputs of the AND circuits 78 and 79 becomes “H”. At this time,
The bottom plate 41 of the thawing chamber 15 has a low temperature in a frozen state (for example,-
(20 ° C.), the temperature is lowered due to heat conduction of the thawing dish 44 on which the food 45 to be thawed is placed. That is, the temperature detector 43 is in a state where the temperature is sufficiently low. Therefore, the output of the comparator 74 is “L”, and the signal inverted to “H” by the inverter 83 is AN
It is input to the other input of the D circuit 78. On the other hand, an AND circuit
An “L” signal that does not pass through the inverter 83 is directly input to 79. Therefore, the output of the AND circuit 78 is “L”, and the AND circuit 79
Is low, timers 76 and 77 do not operate and O
The output of R circuit 80, 81 becomes “H”, and transistors 84, 85 become O
N Then, the relay coils 87 and 88 are energized, the relay contacts 56 and 57 are closed, and the far-infrared heater 34 and the heater 42 are continuously energized. Then the thawing action proceeds and the temperature detector
When the temperature of 43 rises to a predetermined temperature (for example, 30 ° C.) (the time required for this is set to t _0, and this period is set to the first stage), the output of the comparator 74 becomes “H”, The signal of "L" is input to the AND 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 start outputting the "H" and "L" signals alternately and repeatedly at a predetermined interruption rate.
For this reason, the transistors 84 and 85 are turned ON / OFF via the OR circuits 80 and 81 at the intermittent output rate corresponding thereto. The energization of the relay coils 87 and 88 is interrupted, and the relay contacts 56 and 57 open and close intermittently. As a result, the far-infrared heater 34 has a duty ratio of 80% for the time t ₁ following this continuous energization time t ₀ (this period is the second stage) and the next time t ₂ (this period is the third stage). ) Is controlled such that the heat generation capacity is reduced stepwise with the passage of time at an electricity supply rate of 40%. In addition, the heater 42 has a time t ₁ ′ following the time t _{0 of the} continuous energization, and an energization rate of 80.
% And the next time t ₂ ′ are controlled so that the duty ratio is 0% and the heat generation capacity decreases. As described above, in the initial stage of thawing when the temperature of the food to be defrosted 45 is low, the far infrared heater 34 and the heater 42 are continuously energized until the temperature of the temperature detector 43 rises to the predetermined temperature. Even if the weight changes variously, the thawing time can be rapidly advanced under the condition of large calorific value without excess or shortage by the time appropriate for each weight depending on the degree of temperature rise of the temperature detector 43. Can be shortened. Then, after that, the heat generation capacity gradually decreases as time passes, and thawing proceeds while suppressing an increase in the surface temperature of the food 45 to be thawed. During the thawing, the radiant heating from the far-infrared heater 34 is performed evenly from the top surface of the food 45 to be defrosted in combination with the reflection action of the reflection plate 39, and the heat transfer heating by the heater 42 is simultaneously performed from the bottom surface. Will be. Here, in the heating of the far infrared heater 34, 5
Since far-infrared rays having a long wavelength of μm or more are radiated to the food 45 to be thawed, far-infrared rays are efficiently absorbed by general foods having an absorption wavelength band in the far-infrared wavelength range, and Thawing proceeds in a state where it relatively penetrates into the inside and the temperature unevenness between the surface and the center does not become relatively large.
Further, in the heating by the heater 42, the bottom surface of the food 45 to be thawed, which cannot be sufficiently heated by the far infrared heater 34, can be thawed by heat transfer heating through the thawing dish 44.

On the other hand, during the defrosting at the same time as the heating action by the far infrared heater 34 and the heating heater 42, that is, during the first, second and third stages in which the output of the timer 75 continues to generate the "H" signal, the output of the OR circuit 82 Becomes "H", the transistor 86 turns on, and the relay coil 89 conducts. For this reason, the relay contact 55 is closed, and the blower 18 is forcibly operated regardless of the output of the freezer compartment temperature control device 60. On the other hand, during this period, the output of the timer 77a is "L" because the output of the comparator 74 is "L" and the output of the AND circuit 79 is "L" in the first stage. When the output of the AND circuit 79 changes to “H” in the subsequent second stage, the output of the timer 77a is “H” in the second stage,
Becomes “L”. Therefore, the output of the AND circuit 70a is also
1, the second stage is "H", the third stage is "L", and the transistor 71 is ON, ON, OFF during that time. That is, during the thawing, the damper 24 of the thawing room damper thermometer 20 has a pattern in which the first and second stages are forcibly opened and the third stage is forcibly closed.

Thus, the first and second stages are performed with the opened damper 24.
The cool air forcedly blown by the blower 18 through the
Through the outlet 51 and into the ventilation passage 50 in the upper part of the thawing chamber 15. The cool air that has flowed into the ventilation path 50 is discharged downward from a number of ventilation holes formed in the reflection path 39, and uniformly cools the surface of the food 45 to be thawed. By this action, the food 45 to be thawed mainly has a far-infrared radiation effect of the far-infrared heater 34 and a control effect of gradually reducing the heat generation capacity of the far-infrared heater 34 and the heater 42, and furthermore, the temperature rise of the surface portion. As a result, the temperature difference between the central part and the surface part is small, and the thawing with less uneven thawing proceeds. Then, the thawing progresses considerably, and after the end of the second stage (for example, the center temperature of the food 45 to be thawed is around -5 ° C),
The thawing process proceeds gradually in a state where the damper 24 of the damper thermo 20 is forcibly closed and cool air is not introduced and the amount of heat generated by the heater is small. Food to be thawed during this time
The heating efficiency of the heater and the heat absorption efficiency of the food 45 to be thawed are reduced due to the rise in the temperature of the product 45, but the residual heat in the defrosting chamber 15 is reduced by the suction port due to the closed damper 24. 52
And is not returned to the cooler 17. For this reason, the heat load on the cooler 17 is reduced correspondingly, and unnecessary operation of the compressor 16 can be avoided. FIG. 6 shows a temperature characteristic and a time chart of the food 45 to be thawed during thawing.

Regarding the thawing time, the effect of the internal penetration of far-infrared rays and the continuous heating control at the beginning of thawing enable thawing in a relatively short time (for example, about 30 mm for a 500 g weight, 25 mm thick tuna), and the reflector 39 The temperature of the reflection plate 39 itself and the peripheral members, which are originally considerably high because they are exposed in the ventilation passage 50, are cooled and lowered, which is advantageous in safety.

Such a thawing action progresses and the time t ₀ + t ₁ + t ₂ = t ₀ +
t ₁ ′ + t ₂ ′ That is, when the total time of the first, second, and third steps has elapsed, the outputs of the timers 76 and 77 become “L”, and are input from the timer 76 to the reset terminal of the timer 75. The output of the timer 75 also becomes “L”. Because of this, the transistor
When 84 and 85 are turned off, respectively, the energization of the relay coils 87 and 88 is cut off, the relay contacts 56 and 57 are opened, and the energization of the far infrared heater 34 and the heater 42 is cut off and the thawing is completed. At the same time, one input of the OR circuit 82 becomes “L”, so that the forced operation state of the blower 18 is released. Also, timer 77a
Returns to "H", one input of the AND circuit 70a becomes "H", and the forced closed state of the damper 24 of the thawing room damper thermo 20 is released.

After the thawing is completed, the temperature detector
Based on the detected temperature of 31, the temperature inside the thawing chamber 15 is controlled.
Therefore, the food 45 to be thawed after thawing is immediately cooled so as to be stabilized in the partial freezing temperature zone of about -3 ° C, and the temperature does not further rise due to residual heat. Then, even if the thawing is completed, the chill is kept in a partial freezing temperature range of about -3 ° C. which is suitable for preserving raw materials such as fish and meat. Thaws can be thawed with peace of mind without the hassle of processing immediately, and at any time after thawing is complete,
Can be used, which is extremely convenient.

Effects of the Invention As described above, according to the refrigerator with a thawing room of the present invention, the following effects can be obtained.

(1) Heat can be efficiently heated from both sides: far-infrared radiation heating by a far-infrared heater from the top surface, and heat conduction heating by a heater from the bottom surface, and the heating capacity of both heaters gradually decreases during thawing. In addition to the effect of penetrating far-infrared rays into the inside of the food to be thawed, defrosting with less temperature unevenness between the center and the surface becomes possible.

(2) The far-infrared heater and the heating heater are continuously energized until the temperature detector provided on the bottom plate of the thawing chamber rises to a predetermined temperature. Rapid heating can be performed with a heater having a capacity, and thawing in a short time is possible.

(3) The first and second stages during thawing are to forcibly open the damper thermostat for the thawing room and to forcibly continuously operate the blower to allow the food to be thawed from the ventilation path formed in the back space of the reflector. Since the cool air is allowed to flow downward, the surface portion of the food to be thawed is uniformly cooled, and furthermore, the temperature rise is suppressed, and thawing with less thawing unevenness can be realized.

(4) In the third stage during the thawing, the damper thermostat is forcibly closed, so that the residual heat in the thawing room is not returned to the cooler and does not become a heat load. Therefore, unnecessary cooling operation of the compressor can be reduced.

(5) During thawing, the reflection plate and other peripheral members, which would normally be high in temperature, are exposed to the ventilation passage and cooled, so that the temperature is lowered and the safety is favorable.

(6) After the thawing is completed, the thawing room is kept cool in a third temperature zone (for example, a partial freezing temperature zone of about −3 ° C.) between the freezing room temperature and the storage room temperature. The temperature of the thawed food does not further rise, and even if it is left as it is, freshness is maintained at a temperature suitable for raw fish and the like, and the food can be used at any time.

[Brief description of the drawings]

FIG. 1 is a perspective view of a thawing chamber of a refrigerator with a thawing chamber according to one embodiment of the present invention, FIG. 2 is a cross-sectional view of the thawing chamber of FIG. 1 taken along the line AA ', and FIG. FIG. 4 is a longitudinal sectional view of a refrigerator with a thawing room having a thawing room, FIG. 4 is an enlarged sectional view of a damper thermostat provided at the entrance of the thawing room of FIG. 1, and FIG. FIG. 6 is an electric circuit and control circuit diagram of the refrigerator, 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 thawing box showing a conventional example, and FIG. It is BB 'sectional drawing of a thawing box. 13… Freezer room, 14… Refrigerator room, 15… Thaw room, 16 …… Compressor, 17 …… Cooler, 18 …… Blower, 20 …… Damper thermo, 34 …… Far infrared heater, 39… … Reflector, 40 …… Hot air hole, 41 …… Bottom plate, 42 …… Heating heater, 43 …… Temperature detector, 44 …… Thaw plate, 45 …… Thawed food, 49 …… Door, 50
…… Ventilation passage, 73 …… Thaw control device.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-89476 (JP, A) JP-A-64-57079 (JP, A) JP-A-58-208573 (JP, A) JP-A 64-64 6687 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) F25D 23/12

Claims (1)

(57) [Claims] (1) surrounding the outer periphery of a freezer compartment and a refrigerator compartment with a heat insulating material;
A thawing chamber provided with a door that can be opened and closed at the front opening, a compressor and a cooler of a refrigeration cycle, and a blower for forcibly ventilating the air cooled by the cooler to the refrigeration room, the refrigerator room, and the thawing room; A far-infrared heater provided at the top of the thawing chamber, a metal bottom plate provided at the bottom of the thawing room, a heater heater in heat conductive contact with the back surface of the bottom plate, and a back surface of the bottom plate. A temperature detector closely adhered to the center in a thermally conductive manner, a metal reflector that covers the upper surface of the far-infrared heater in a dome shape, and a thermally conductive plate on which the food to be thawed is placed, And a thawing plate that is detachably installed, a damper thermo that is provided at an inlet of the chill air of the thawing chamber and controls an inflow amount of the cool air by an electric input, and communicates with the damper thermo,
A ventilation path formed in the upper space on the back surface of the reflection plate, a number of ventilation holes provided in the reflection plate for communicating the ventilation path with the thawing chamber, forcibly operating the blower during thawing, and setting the thawing time to three stages. And the time from the start of thawing until the temperature of the temperature detector rises to a predetermined temperature is set as the first stage, and the far-infrared heater and the heating heater are continuously energized. Thereafter, the process proceeds to the second and third stages. And the two heaters are intermittently energized to reduce the intermittent energization rate, the first and second stages are forcibly opening the damper thermostat, and the third stage is forcibly closing the damper thermostat. A refrigerator with a thawing control unit, wherein the thawing control unit keeps the thawing room in a third temperature zone between the refrigeration temperature and the freezing temperature when the thawing operation is not performed.