JPS61208481A - Refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a refrigerator equipped with a thawing section in a refrigeration chamber that thaws frozen foods using air inside the refrigeration chamber.

[Technical background of the invention and its problems] Conventionally, in this type of refrigerator, a thawing chamber for storing frozen food is provided in the refrigeration chamber, and air inside the refrigeration room, which is higher temperature than the frozen food, is drawn into the thawing chamber by a fan to store the frozen food. Spray it on the
A common configuration was to heat frozen foods to thaw them. However, this has the disadvantage that it takes a long time to thaw, so recently a heating plate heated by a heater is installed in the thawing chamber, and the frozen food is placed on this heating plate to thaw it. is also provided.

However, while the above configuration allows rapid decompression,
The temperature difference between the inside and the surface of the frozen food becomes large, and by the time thawing has progressed to the inside, the surface temperature becomes too high. For example, when defrosting meat or fish, meat juices ooze from the surface, which not only makes the food look bad, but also causes the food to thaw. The disadvantage is that it spoils the taste.

[Object of the Invention] An object of the present invention is to provide a refrigerator that can prevent food from deteriorating in appearance and taste while enabling rapid defrosting in a defrosting section provided in a refrigerator compartment.

[Summary of the Invention] The present invention provides a thawing section with a heater that heats frozen food and a fan that blows air from the refrigerator room onto the frozen food, and also stops the fan after power is cut off to the heater. The feature is that it uses the heat from the heater to quickly heat up the product, and at the end of thawing, the heater is cut off and the refrigerator is heated only by the air inside the refrigerator, thereby suppressing excessive temperature rises on the surface. It has the following.

[Embodiment of the Invention] A first embodiment of the invention will now be described with reference to FIGS. 1 to 4.

In FIG. 1 showing a partial vertical cross-sectional view of the refrigerator, 1 and 2
4 is a freezer compartment and a refrigerator compartment which are divided into upper and lower sections by a heat insulating wall 3, and 4 is a cooler storage room formed within the heat insulator wall 3. The cooler storage room 4 is connected to the freezer compartment through cold air passages 5 and 6, respectively 1 and the refrigerator compartment 2, respectively. A cooler 7 and a cold air circulation fan 8 are provided in the cooler storage chamber 4, and the cold air generated by the cooler 7 is passed through a cold air circulation fan 8.
is supplied into the freezer compartment 1 and the refrigerator compartment 2, respectively. A damper device 9 is provided in the cold air passage 6 extending to the refrigerator compartment 2 side, and controls the amount of cold air flowing into the refrigerator compartment 2 from the cooler storage compartment 4 side to increase the inside of the refrigerator compartment 2. The temperature is maintained at a low temperature. Reference numeral 10 denotes a thawing chamber, which is a thawing section provided in the refrigerator compartment 2. This is partitioned by a thawing case 11 located on the lower surface of the heat insulating wall 3, and a saucer 13 on which a frozen food 12 can be placed is located inside. It is located in

Openings 11a and 11b communicating with the inside of the refrigerator compartment 2 are formed on the front and rear lower surfaces of the defrosting case 11, and a fan 14 is disposed at the rear of the interior, and by driving the fan 14, the opening 11a is opened. .

The air inside the refrigerator is allowed to flow into the thawing case 11 through 11b and can be blown against the frozen food 12 placed on the saucer 13. Reference numeral 15 denotes a heater for heating the frozen food 12 provided in contact with the lower surface of the saucer 13. Reference numeral 16 denotes a temperature sensor provided on the saucer 13, which is constantly biased upward by a spring piece 17 provided on the saucer 13.
2 and can detect its surface temperature.

Next, in FIG. 2 showing the electrical configuration, 18 is a comparator, and a reference voltage divided by a series circuit of a variable resistor 19 and a resistor 20 is input to its non-inverting input terminal (+). , a detection voltage divided by the temperature sensor 16 having a negative temperature characteristic and the resistor 21 is input to the inverting input terminal (-). A series circuit of a variable resistor 22 and a diode 22a is connected between the output terminal of the comparator 18 and the non-inverting input terminal (+).
A predetermined hysteresis is provided by appropriately setting . That is, as shown in FIG.
below), the output terminal of the comparator 18 becomes high level, and when it reaches the heater off temperature Hoff, it changes to low level, and even if the food surface temperature decreases thereafter, the predetermined fan off temperature Foff (this implementation In the example, 11
℃), and when the fan-off temperature F″off is reached, the output terminal becomes high level again. and is connected to the clear terminal CL of the counter 24.Counter 2
4 outputs a high level signal to the output terminal Q when a high level signal is given to the clear terminal CL, and when the clear terminal CL becomes low level and then changes to high level again, a low level signal is output to the output terminal 0. Outputs level signal. Output terminal 0 of the counter 24 is connected to the AND circuit 23 of the three-person type.
It is connected to the - input terminal of the input terminal and the input terminal of the two-manufactured AND circuit 25. The output terminal of the three-person-powered AND circuit 23 is connected to the base of a transistor 27 that controls a relay 26 for turning on and off the heater 15, and the output terminal of the two-person-type AND circuit 25 turns on and off the fan 14. It is connected to the base of a transistor 29 that controls a relay 28 that operates. On the other hand, 30 is a flip-flop, one input terminal 30a of which is connected to a defrosting start switch 31, and the other input terminal 30b of which is connected to a defrosting interrupt switch 3.
2 are connected. Further, the input terminal 30b of the flip-flop 30 is connected to the output terminal 0 of the counter 24 via a diode 33. The output terminal Q of the flip-flop 30 is connected to the 3-person type AND circuit 2.
3 and 2 are connected to the remaining input terminals of the AND circuits 25, respectively.

Next, the operation of this embodiment will be explained. Thawing case 11
When the frozen food 12 is placed on the tray 13 inside and the thawing start switch 31 is turned on, the output terminal of the flip-flop 30 becomes high level and the temperature sensor 16 detects the food surface temperature of the frozen food 12. . Frozen food 12
Since the initial temperature is approximately equal to the temperature inside the freezer compartment 1, which is approximately -18°C, the output terminal of the comparator 18 becomes a high level. In addition, because of this, the output terminal of the counter 24 also becomes high level, so the output terminals of each AND circuit 23 and 25 become high level, transistors 27 and 29 are turned on, and both the fan 14 and heater 15 of the defrosting chamber 10 are turned on. It is energized (see Figure 4). Then, frozen food 12 becomes
The air in the refrigerator which is heated by the heater 15 through the saucer 13 and whose temperature is higher than that of the frozen food 12 is sent to the fan 1.
It is heated by being sprayed with water by 4. In this case, the temperature of the frozen food 12 rises relatively quickly,
As shown in FIG. 4, the food surface temperature tends to be higher than the center temperature. Then, when the food surface temperature rises to the heater off temperature Hoff, the comparator 18
Since the output terminal of the triple AND circuit 23 becomes low level, the transistor 27 is turned off, and the heater 15 is immediately cut off. Therefore, from this point on, only the air in the refrigerator room blown by the fan 15 is used for heating, and the heating speed of the frozen food is reduced. As a result, since the temperature at the center of the frozen food 12 is still quite low, the heat from the surface is transferred to the center, and the food surface temperature begins to drop again without being maintained at about 4°C. Then, when the food surface temperature drops to the fan-off temperature FoH of 11°C, a high level signal is output from the output terminal of the comparator 18, and the output terminal 0 of the counter 24 changes to low level. The output terminal of the AND circuit 25 becomes low level and the transistor 2
is turned off, the fan 14 is stopped, and defrosting is completed.

Incidentally, even if the output terminal of the comparator 18 becomes high level again, the output terminal of the counter 24 becomes low level at the same time, so the output terminal of the 3-person AND circuit 23 maintains the low level, and the heater 15 It will not be energized again. In addition, if you wish to interrupt the defrosting process during the defrosting process, turn on the defrost interrupt switch 32, and the flip 70 tab 30 will be reversed and each AND circuit 23
．． The output terminal 25 becomes low level, the fan 14 and the heater 15 are both cut off, and thawing is interrupted.

As described above, in this embodiment, since the frozen food 12 is heated by both the heater 15 and the fan 14 at the beginning of thawing, the temperature of the frozen food 12 can be quickly raised, and the thawing time is controlled by the fan. It is possible to significantly shorten the time compared to the case using only 14. Furthermore, although the frozen food 12 is heated by both the fan 14 and the heater 15, the heater 15 is first cut off when thawing has progressed to a certain extent, and then the fan 14 is stopped. Therefore, it is possible to prevent the surface temperature of the frozen food 12 from increasing more than necessary by lowering the surface temperature of the frozen food 12 again after the heater 15 is stopped. Therefore, even when thawing frozen foods such as meat and fish, it is possible to prevent meat juices from seeping out of the frozen foods 12, making them look bad, making cooking difficult, and even spoiling the taste. This can be reliably prevented. In addition, especially in this embodiment, lWi of the heater 15
Since heating is performed when the food surface temperature of the frozen food 12 reaches a predetermined value or more by the temperature sensor 16 that detects the temperature of the frozen food, the amount of heating by the heater 15 is controlled regardless of the amount of the frozen food 12. Appropriate thawing can always be carried out without causing excess or deficiency.

Next, a second embodiment of the present invention will be described with reference to FIGS. 5 and 6. The basic difference between this embodiment and the first embodiment is that the power-off timing of the heater 15 is controlled by a timer circuit, and the same parts as in the first embodiment are given the same reference numerals. Detailed explanation will be omitted. In FIG. 5, 34 is a switch for starting and interrupting defrosting, and 35 is a defrosting timer.

The defrosting timer 35 changes its oscillation frequency by appropriately adjusting the variable resistor 36 according to the amount of frozen food, and operates during the set time on the condition that the switch 34 is operated to start defrosting. A high level signal is output to the output terminal Q, and thereafter becomes a low level. The output terminal Q of the defrosting timer 35 is connected to a transistor 27 that controls a relay (not shown) that turns on and off the heater 15, and is also connected to a delay timer via one input terminal of an OR circuit 37 and an inverter circuit 38. It is connected to 39. When a high level signal is applied to the input terminal IN, the delay timer 39 outputs a high level signal to the output terminal Q for a predetermined period of time. The output terminal of the OR circuit 37 is connected to a transistor 29 that controls a relay (not shown) that turns on and off the fan 14, and drives the fan 14 when the output terminal of the OR circuit 37 becomes high level. .

In the above configuration, the frozen food 12 is stored in the thawing chamber,
If the variable resistor 36 is set appropriately according to the amount of frozen food 12 and the switch 34 is turned on, the thawing timer 35 is activated.
The output terminal Q becomes high level, and the fan 14 and heater 15 are energized.

In this way, similarly to the first embodiment, the frozen food 12 is heated by the heat from the heater 15 and the air in the refrigerator room,
Temperature rises quickly. When the time set in the defrosting timer 35 has elapsed, the output terminal Q becomes a low level, so that the heater 15 is cut off, and a high level signal is given to the input terminal IN of the delay timer 39 to stop it. Output terminal Q changes to high level. Therefore, the fan 14 continues to be driven, and the surface temperature of the frozen food 12 begins to decrease again, and an excessive rise in the food surface temperature is suppressed. Then, when a predetermined period of time has elapsed after the heater 15 was turned off,
Since the output terminal Q of the delay timer 39 changes to a low level, the fan 14 stops with a delay from the heater 15 being cut off.

In this way, since the fan 14 is stopped after the heater 15 is turned off in this embodiment, it is possible to quickly heat the frozen food 12 while suppressing an excessive rise in food surface temperature. It is possible to reliably prevent spoiling the appearance and taste of the food.

In each of the above embodiments, the fan 14 is turned on at the beginning of defrosting.
Although both the power supply and the heater 15 are energized, the present invention is not limited to this, and is configured such that heating is performed only by the heater at the beginning of defrosting, the fan is driven only after the heater is cut off, and the fan is then stopped. You may do so.

[Effects of the Invention] As described above, the present invention includes a heater that heats frozen food and a fan that blows air from the refrigerator room onto the frozen food in the thawing section provided in the refrigerator compartment, and the fan is used to disconnect the power from the heater. Since the configuration is configured to stop the food later, the heat from the heater can be used to quickly heat the food, increasing the thawing speed, while preventing the surface temperature of the frozen food from rising excessively. This has the excellent effect of reliably preventing deterioration of appearance and taste.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the present invention, FIG. 1 is a partial vertical sectional view of the refrigerator, FIG. 2 is an electric circuit diagram of the main part,
FIG. 3 is a characteristic diagram showing the hysteresis of the comparator, FIG. 4 is a time chart shown in response to temperature changes of frozen foods, and FIGS. 5 and 6 show a second embodiment of the present invention.
FIG. 5 is a block diagram of the main part, and FIG. 6 is a diagram corresponding to FIG. 4. In the drawing, 1 is a freezer compartment, 2 is a refrigerator compartment, 10 is a thawing compartment (thawing section), 12 is a thawing case, 12 is a frozen food, 14 is a saucer, 15 is a heater, 16 is a temperature sensor, and 39 is a delay timer. be. 1st mouth 3rd figure 4th figure 5th figure 6th figure

Claims (1)

[Claims] 1. In a refrigerator provided with a thawing section for thawing frozen foods using the air in the refrigerator, the thawing section includes:
A refrigerator comprising: a heater that heats the frozen food; and a fan that blows air inside the refrigerator onto the frozen food; and the fan is stopped after power is cut off to the heater.