JPH0749904B2 - refrigerator - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator provided with a quick freezing device for forcibly operating a compressor for a certain period of time.

2. Description of the Related Art A conventional example will be described with reference to FIGS. In the figure, 1 is a refrigerator main body, which is an outer box 2, an inner box 3, and both boxes 2, 3
The heat insulating material 4 is filled in between. 5 is a partition wall, inside which a cooler 6 and a blower 7 for forced ventilation are housed,
The front end face is provided with a partition plate 8 and a high pressure refrigerant pipe 9 of the refrigeration cycle for contacting the rear surface of the partition plate 8 in a heat conductive manner to prevent dew condensation on the surface of the partition plate 8. A freezer compartment 10 is formed above the partition wall 5, and a refrigerating compartment 11 is formed below. Reference numeral 12 is a duct for guiding the cool air cooled by the cooler 6 to the freezer compartment 10 and the refrigerating compartment 11 by the blower 7, and cold air flows into the inlet of the refrigerating compartment 11 according to the temperature of the refrigerating compartment 11. A damper thermostat 13 for adjusting the quantity is provided. Reference numeral 14 is a refrigeration cycle compressor, and 15 is a temperature detector such as a thermistor provided in the freezing chamber 10 for controlling the operation and stop of the compressor 14 and the blower 7.

Next, the control circuit will be described.

After the compressor 14 and blower 7 are connected in parallel, relay contact
Connected to power supply through 16. Reference numeral 17 denotes a temperature control device, which includes a temperature detector 15 such as a thermistor, resistors R ₁ , R ₂ , and R ₃ , a comparison circuit including a comparator 18, an OR circuit 19, a transistor 20, and a relay coil 21.
The output of 18 is connected to one input of the OR circuit 19. The output of the OR circuit 19 is connected to the base of the transistor 20, and the collector of the transistor 20 is connected to a suction relay coil 21 for opening and closing the relay contact 16. Reference numeral 22 denotes a quick freezing device, which is composed of a quick freezing switch 23 and a timer 24. The timer 24 outputs an output signal "High" (hereinafter referred to as "H") only for a certain time when the quick freezing switch 23 is turned on. Occur. The outlet of the timer 24 is connected to the other input of the OR circuit of the temperature control device 17.

In such a configuration, when the temperature of the freezer compartment 10 is higher than a predetermined value, the resistance R _TH of the temperature detector 15 is small,
The potential of the point A determined by the resistors R _TH and R ₁ becomes higher than the potential of the point B determined by the resistors R ₂ and R ₃ , and the output of the comparator 18 becomes “H”. One input of the circuit 19 becomes "H", that is, the output also becomes "H", the transistor 20 is turned on, and the relay coil 21 is turned on. Then, the relay contact 16 is closed to operate the compressor 14 and the blower 7 to cool the freezer compartment 10 and the refrigerating compartment 11. After that, if the freezer compartment 10 is cooled to a predetermined temperature, the resistance value R _TH of the temperature detector 15 increases and the A potential becomes smaller than the B potential, so that the comparator
18 generates a "Low" (hereinafter referred to as "L") signal. Therefore, one input of the OR circuit 19 becomes "L", and if the quick freezing switch 23 is not turned on, the other input is also "L", and its output also becomes "L". Then, the transistor 20 is turned off and the conduction to the relay coil 21 is cut off,
The relay contact 16 is opened and the compressor 14 and the blower 7 are stopped.

Next, the case of quick freezing will be described.

When the quick freezing switch 23 is turned on, the "H" signal is sent to the timer 24.
Is input to the timer 24, the timer 24 starts integration for a predetermined fixed time and continues to output the "H" signal during that time. Therefore, one input of the OR circuit 19 is always "H" for a certain time,
The output of the OR circuit 19 becomes "H" regardless of the output of the comparator 18 of the temperature control device 17. That is, transistor 20
Is turned on, the relay coil 21 is turned on, and the relay contact 16 is closed. Then, the compressor 14 and the blower 7 are forcibly operated for a certain period of time to exert the quick freezing effect as shown in FIG.

Problems to be Solved by the Invention However, in such a configuration, as shown in FIG.
At the end of the quick freezing, the temperature of the temperature detector 15 is also extremely low because the inside of the freezing chamber 10 is maintained at a considerably low temperature, and after the quick freezing is completed, the compressor 14 and the blower 7 are stopped. Even if the temperature starts to rise, it takes a very long time to reach the temperature at which the compressor 14 and the blower 7 should be operated next. That is, during normal cooling stable operation
Although the cycle is repeated with ON / OFF time t ₁ / t ₂ min, the OFF time immediately after the end of quick freezing is t ₃ min, which is usually t ₂
If it is ≅15 min, it will be extended to t ₃ ≅60 min, and this tendency becomes stronger as the outside air temperature becomes lower. Therefore, for example, when the outside air temperature is 30 ° C., the compressor 14 is stopped during a long OFF time immediately after rapid freezing and the heat source to the high pressure refrigerant pipe 9 is lost, so that the cooler 6 and the freezer compartment 1
0, the surface temperature of the partition plate 8 is greatly reduced due to the influence of the low temperature source of the refrigerating room 11. For example, the surface temperature of the partition plate 8 is significantly lower than the dew point temperature T = 27.2 ° C when the relative humidity of the outside air is 85%. As a result, there is a problem that a large amount of dew condensation occurs in the peripheral part and drops as water drops. At the same time,
Refrigerating room that does not actively perform supercooling even during quick freezing
Regarding No. 11 as well, there was a problem that the room temperature greatly rises because there is no cooling source at the time of long OFF immediately after the end of quick freezing.

The present invention solves the above-mentioned problems, and an object of the present invention is to prevent dew condensation on the partition plate surface and temperature rise in the refrigerating compartment at the time of stopping immediately after the end of quick freezing.

Means for Solving the Problems In order to solve the above problems, the present invention controls a compressor based on a predetermined stop and operation cycle within a fixed time after completion of quick freezing according to the outside air temperature. It is configured to do.

Action The present invention has the above-described configuration, and immediately after the end of the quick freezing, the predetermined forced stop, regardless of the ordinary temperature control device,
The compressor is operated intermittently by the operation cycle, and it shifts to the control by the normal temperature control device while satisfying most of the required heating amount for the partition plate and the required cooling amount for the refrigerating room. .

EXAMPLES An example of the present invention will be described below with reference to FIGS. 1 to 4. In addition, the same reference numerals are given to the same configurations as the conventional ones,
Detailed description thereof will be omitted and only different parts will be described.

In the figure, 25 is a quick freezing device, which is a quick freezing switch 23, an outside air temperature detecting device 26, an inverter 27, an AND circuit 28,2.
9. It consists of timers 30 and 31. Here, the outside air temperature detecting device 26 is attached to a part of the outer shell of the main body, and an outside air temperature detector 32 such as a thermistor, resistors R ₄ , R ₅ , R ₆ and a comparator 3 are provided.
Comprising a comparator circuit with 3. Further, the timers 30 and 31 will be described. Both timers 30 and 31 start integration for a fixed time at the same time when the "H" signal is input, and during that time, the output keeps generating the "H" signal. When a certain accumulated time has elapsed, this is also switched to a predetermined “L” → “H” time cycle, and after the switching, the total time including “L” and “H” has passed a certain time. It is configured to reset for the first time. Of these, the timer 30 is for relatively high outside air temperature, and the timer 31 is for low outside air temperature, "H" / ("H" in the time cycle of "L" → "H" depending on the outside air temperature.
+ "L") ratio is changed. The total time including "L" and "H" is also changed according to the outside air temperature.

The output of the quick freezing switch 23 is connected to one of the inputs of the AND circuits 28 and 29, and the outputs of the AND circuits 28 and 29 are connected to the inputs of the timers 30 and 31, respectively. Also, timer 30,
The output of 31 is merged and the OR circuit 19 of the temperature control device 17 is combined.
Connected to one input. The outside air temperature detecting device 26
One of the outputs of the comparator 33 of the AND circuit 28 is
The other is connected to the AND circuit 29 via the inverter 27.

In such a configuration, when the quick freezing switch 23 is turned on, the "H" signal is input to either one of the AND circuits 28 and 29.
At this time, if the outside air temperature is relatively high (for example, 30 ° C.), the resistance value R _TH ′ of the temperature detector 32 of the outside air temperature detecting device 26.
Becomes smaller, the potential at the point C determined by the resistance value R _TH ′ and the resistance R ₄ becomes higher than the potential at the point D determined by the resistors R ₅ and R ₆ , and the output of the comparator 33 becomes “H”. "become. Therefore, the "H" signal also enters the other input to the AND circuit 28 as it is, and is converted into "L" by the inverter 27 and input to the AND circuit 29. Therefore, as outputs, the AND circuit 28 becomes "H" and the AND circuit 29 becomes "L", and the timer 30 is selected. When the "H" signal is input to the timer 30, time integration is started and the "H" signal is continuously output. Therefore, regardless of the other input, the output of the OR circuit 19 becomes "H", the transistor 20 turns ON, and the relay coil 21 becomes conductive.
Then, the relay contact 16 is closed, the compressor 14 and the blower 7 are forcedly operated, and quick freezing is performed. Then timer 30
When the quick freezing ends after a certain period of time has been accumulated, the timer 30 changes from “L” (t ₄ min) to “H” (t ₅ min) in accordance with a predetermined stop and operation cycle as shown in FIG. The output signal of "L" and "H" is repeated for the total time (tmin) in the cycle. For this reason, the compressor 14 and the blower 7 are also intermittently operated at "H" each time to intermittently supply a heating source to the high-pressure refrigerant pipe 9, so that the surface temperature of the partition plate 8 is, for example, a dew point temperature T at a relative humidity of 85%. It does not fall much below 27.2 ° C and a large amount of condensation does not occur. On the other hand, forced ventilation of the blower 7 is also intermittently performed on the refrigerating compartment 11, so that the temperature rise can be suppressed. In addition, the operating rate t ₅ / (t ₅ + t ₄ ) of the intermittent cycle of this stop and operation
Is generally lower than the operation rate t ₁ / (t ₁ + t ₂ ) during normal stable cooling, and in general, the normal temperature control can be smoothly performed.

Next, when the outside air temperature is lower than a predetermined value (for example, 10 ° C.), the resistance value R _TH ′ of the outside air temperature detector 32 is large, and the potential at the point C is lower than the potential at the point D. Therefore, the output of the comparator 33 becomes "L". Therefore AN
One input of the D circuit 28 becomes "L" and the output also becomes "L".
The input of the circuit 29 becomes "H" and the timer 31 is selected. As shown in FIG. 4, the stop time immediately after the end of quick freezing generally becomes particularly long under a low outside air temperature, so the total time t'where the intermittent cycle of stop and operation is put is set to be long.
In addition, since the operating rate during normal stable cooling is different from that during high outside temperature, the operating rate for intermittent cycles t ₅ ′ / (t ₅ ′ +
The setting of t ₄ ′) is changed from the high outside air temperature so that the operating rate t ₁ ′ / (t ₁ ′ + t ₂ ′) under normal conditions is also lower. And
As a result, even when the outside temperature is low, the surface of the partition plate does not greatly fall below the dew point temperature T '= 7.7 ° C at a relative humidity of 85%, and the rise in the refrigerating room temperature can be suppressed, which is the desired effect. Is obtained.

Effects of the Invention As is apparent from the above description, according to the present invention, the following effects can be obtained.

(1) It is possible to rationally prevent a large amount of dew condensation around the partition plate immediately after rapid freezing in accordance with the outside air temperature.

(2) It is possible to suppress the temperature rise in the refrigerating chamber after the end of the quick freezing.

[Brief description of drawings]

FIG. 1 is a control circuit diagram of a refrigerator showing an embodiment of the present invention,
Fig. 2 is a vertical sectional view of the refrigerator, and Fig. 3 is the outside air temperature of 30 ℃.
Fig. 4 is a temperature characteristic diagram in Fig. 4, Fig. 4 is a temperature characteristic diagram in the same outside air temperature of 10 ° C, and Fig. 5 is a vertical sectional view of a conventional refrigerator.
FIG. 6 is a control circuit diagram of the refrigerator, and FIG. 7 is the outside air temperature 30.
It is a temperature characteristic in ° C. 10 ... Freezer room, 11 ... Refrigerator room, 14 ... Compressor, 17 ... Temperature control device, 25 ... Quick freezing device, 26 Outside air temperature detection device.

Claims (1)

[Claims] 1. A freezing compartment (10), a refrigerating compartment (11), a temperature control device (17) for detecting the temperature in the freezing compartment and controlling the operation of a compressor (14) of a refrigeration cycle, A quick freezing device (25) forcibly operating the compressor for a certain period of time, an outside air temperature detecting device (26) for detecting the outside air temperature, and the outside air temperature detecting device of the outside air temperature detecting device within a predetermined time immediately after the operation of the quick refrigeration device ends. A refrigerator provided with a means for forcibly performing the intermittent operation of the compressor regardless of the temperature control device at an intermittent operation rate that is predetermined so as to decrease in accordance with a decrease in the outside air temperature based on the output.