JPS6142068Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a defrosting device that eliminates the adverse effects of defrosting on food, eliminates wasteful power consumption, and achieves a power saving effect.

Conventional defrosting devices used in refrigerators, etc. are equipped with a defrost heater attached to the cooler in order to remove the frost that accumulates on the cooler during cooling.
Electricity was applied to this heater to melt the frost, and after defrosting, the temperature of the cooler was detected by a thermometer such as a bimetal, and the electricity to the defrost heater was cut off, at the same time driving the compressor and blower fan.
In this type of system, the blower fan is activated immediately after defrosting, so the warm air near the cooler is sent into the freezer, raising the temperature inside the freezer and cooling it further to a lower temperature. This was extremely uneconomical.

Below, the conventional example will be explained in detail based on FIG.
When the refrigerator-freezer is energized as indicated by a dot, the cooler temperature 1 is lowered, and the temperature 2 of the freezer compartment is also lowered by the cold air sent from the cooler by the drive of the blower fan.
When the temperature reaches point b, the compressor is turned off by the freezer thermometer installed in the freezer for temperature control, and the temperature of both the cooler and the freezer gradually rises. After that, the temperature inside the freezer reaches c.
When the temperature reaches this point, the freezer thermo is turned on, the compressor is energized, and the cooler and freezer compartment are cooled.

By repeating the above operations, the temperature inside the freezer is usually A.
The temperature is maintained between ℃ and B℃, but when the refrigeration cycle is operated for a long time (although it is an intermittent operation...), frost gradually forms on the surface of the cooler, and as the frost accumulates, There is a drawback that the cooling capacity of the cooler is reduced and the temperature inside the freezing chamber becomes higher than a predetermined temperature (in the range of A° C. to B° C.). Therefore, conventionally, when the cumulative time of the compressor reaches a certain time (e.g. 8 hours), the defrost heater is energized (point d in Figure 1) with the compressor and fan turned off to melt the frost that has adhered to the cooler. Then, the defrosting thermometer detects the end of defrosting and energizes the compressor and blower fan (Fig. 1e).
point). The temperature of the cooler is always the same after defrosting, but if you start the fan at this point, warm air near the cooler will enter the freezer compartment, raising the temperature inside the freezer and having a negative impact on frozen foods. Not only that, but it was also a waste of power consumption (point f in Figure 1).

The present invention has been devised to eliminate the above-mentioned drawbacks and will be explained in detail below with reference to an embodiment shown in the drawings.
Reference numeral 11 is a defrosting heater that heats the cooler, and is energized at regular intervals (for example, 8 hours) to remove frost that has adhered to the surface of the cooler. 12 is a temperature detection means such as a thermistor for detecting the temperature inside the freezing chamber, and 13 is another temperature detection means such as a thermistor for detecting the surface temperature of the cooler.
Reference numeral 14 designates a control circuit having a detection means for detecting that the temperature in the freezer compartment and the cooler temperature match, and after the defrosting operation is completed, electricity is first applied to only the compressor 15, and then the temperature in the freezer compartment and the cooler temperature are matched. When they match, the blower fan 16 is energized. In Fig. 3, 17 is a line graph showing the cooler temperature, 18 is a line graph showing the temperature inside the freezer, g is a point indicating the start time of defrosting, h is the point at which defrosting is completed, and h-i is the compressor 15. During the period when only the compressor 15 and the blower fan 16 are energized, D is a point where the cooler temperature and the freezer compartment temperature match and the compressor 15 and the blower fan 16 are driven.

Here, the operation of the present invention will be explained. During normal refrigeration cycle operation, the compressor 15 and ventilation fan 16 are operated by the freezer thermometer.
is controlled and the temperature inside the freezing chamber is maintained at a constant temperature. When frost accumulates on the surface of the cooler and the cooling capacity decreases (for example, after 8 hours), power to the compressor 15 and blower fan 16 is cut off, and power is turned to the defrost heater 11. (point g in Figure 2). Therefore, the cooler is heated by the defrosting heater 11 to melt the frost, and the surface temperature of the cooler and the temperature of the freezer compartment rise. After that, when the defrosting operation is completed and the temperature of the cooler reaches point h, the compressor 15 is energized and the temperature of the cooler gradually decreases. At this time, the temperature in the freezing chamber continues to rise gradually compared to before, as shown by the dashed line 18. Then,
The temperature detection means 12 detects that when the temperature reaches point D in FIG.
and 13, the detection means in the control circuit 14 detects this, and the blower fan 16 is energized. At this time, that is, when the blower fan 16 is energized, the surface temperature of the cooler has already been lowered by the operation of the compressor 15, so even if the blower fan 16 is driven, the air heated in the freezer compartment remains at a low temperature. The frozen food stored in the freezer compartment will not be adversely affected.

As described above, the present invention delays the application of electricity to the ventilation fan after defrosting is completed by comparing and matching the temperature of the cooler and the temperature inside the refrigerator. Not only can it eliminate power consumption, but it can also have the remarkable effect of being able to follow changes in the freezer compartment temperature and cooler temperature due to changes in outside air temperature and obtain an accurate operating point. be.

[Brief explanation of the drawing]

Fig. 1 is a temperature change comparison diagram between the cooler temperature and the temperature in the freezer room, showing the operating state of the conventional device, Fig. 2 is the electric circuit diagram of the device of the present invention, and Fig. 3 is the cooler showing the operating state of the same device. A comparison diagram of temperature changes between the temperature and the temperature inside the freezer is shown. 11: Defrosting heater, 12: Temperature detection means in the freezing chamber, 13: Cooler temperature detection means, 14: Control circuit having temperature coincidence detection means, 15: Compressor, 16: Air blower fan.

Claims (1)

[Scope of utility model registration request] A defrosting heater that heats the cooler, a temperature detection means that detects the temperature inside the refrigerator, a temperature detection means that detects the temperature of the cooler, and a detection means that detects that the temperature inside the refrigerator and the temperature of the cooler match. A defrosting device characterized in that it first energizes only the compressor after the defrosting operation is completed, and then energizes the blower fan when the temperature inside the refrigerator and the temperature of the cooler match. .