JPS6030976A - 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 provides a refrigerator that has a refrigerator compartment and a freezer compartment with different set temperatures, and has a function of cooling the freezer compartment by direct cooling and indirect cooling by forced circulation of cold air. Regarding.

[Technical background of the invention and its problems]

Traditionally, refrigerators have a direct-cooling type freezer structure in which the inner box for the freezer compartment is formed by the cooler itself, or those with a direct cooling type freezer structure in which the inner box for the freezer compartment is divided into a freezer compartment and an air duct room and the freezer is stored in the air duct compartment. There is a cold air circulation type that includes a room cooler and a fan device that sends cold air into the freezer compartment. Comparing these performances, in a direct cooling type freezer, the cooling rate of food placed on the empty wall is fast, but the cooling rate of food placed on a shelf or the like floating above the cooling wall is slow. On the other hand, compared to the direct cooling type, the food cooling rate in the cold circulation type is faster for food placed in the air, but slower for food placed on a hard wall surface. Therefore, in both of the above two types of refrigerators, the degree of cooling may become insufficient depending on where food is stored in the freezer compartment.

In addition, such circumstances mean that, for example, when trying to rapidly cool and freeze unfrozen food in a freezer compartment, freezing may take a long time depending on the storage location. There is a problem in that it is undesirable for the preservation of frozen foods. Furthermore, in any type of refrigerator, defrosting of the freezer compartment cooler is performed by stopping the compressor, so there is a problem that the temperature inside the refrigerator tends to rise during defrosting.

(Objective of the Invention) The present invention has been made in view of the above circumstances, and its purpose is to be able to sufficiently cool food in a freezer compartment regardless of where it is stored, and also to cool food particularly rapidly. To provide a refrigerator that can rapidly cool the refrigerator and further prevent the temperature rise inside the refrigerator as much as possible during defrosting of a refrigerator for a freezer compartment.

[Summary of the invention]

The present invention provides a refrigerator equipped with a freezer compartment cooler consisting of an auxiliary cooler for placing food and cooling it, and a main cooler for cooling circulating air by a fan. At times, a forced cooling operation is performed before and after the frost melting operation to suppress the tendency of the temperature inside the refrigerator to rise, and a rapid cooling operation is performed to supply refrigerant only to the freezer compartment cooler using the rapid cooling i1 command. It is characterized by the fact that it enables rapid cooling of food products, and furthermore, it establishes a certain priority relationship between each operation of rapid cooling operation and defrosting operation so that each operation can be executed effectively. has.

[Embodiments of the invention]

A first embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, which shows an outline of a refrigerator, an insulating box 1 has a refrigerator compartment 2 and a refrigerator compartment 3 that are thermally independent from the refrigerator compartment 2, each of which has a door at its front opening. 2a, 3
A is installed so that it can be opened and closed freely. A refrigerator cooler 4 is placed in the refrigerator compartment 2, and an auxiliary cooler 5 is placed in the freezer compartment 3 to directly cool food. In addition, an air passage chamber 6 is formed across the back of the freezer compartment 3 and under the floor, and a main cooler for the freezer compartment 7, which cooperates with the auxiliary cooler 5 to constitute a cooler for the freezer compartment, is arranged in this air passage chamber 6. By driving the fan motor 8), the cold air generated by the main cooler 7 for the freezer compartment is circulated through the freezer compartment 3. The refrigeration cycle of this refrigerator is constructed as shown in FIG. That is, between the discharge port and the suction port of the rotary compressor 10, there are a condenser 11, a first control valve 12, a refrigerator compartment cooler 4, a freezer compartment main cooler 7, an accumulator 13, and a check valve 1.
4, and a second control valve 1 in parallel with the flow path consisting of the first control valve 12 and the refrigeration cooler 4.
5 and an auxiliary cooler 5 are connected to each other. still,
16a to 16e are capillary tubes. FIG. 3 shows the circuit configuration for controlling this refrigeration cycle. In FIG. 3, reference numeral J5 denotes a control section which receives temperature information from the temperature detection unit 18 (and gives a control signal to the drive unit 19, so that the drive unit 19 controls the first control valve 12). The second control valve 15 is controlled to be turned on and off through transistors 20a and 20b, and the defrosting heater 21, damper drive heater 22, and motor 1 attached to the main cooler 7 for the freezer compartment are controlled. 8 and the compressor motor 23 that drives the compressor 10 are connected to the relay contacts 24, respectively.
Power supply/disconnection control is performed from 1 to 27. Here, the tamper drive heater 22 is used to move the damper 28, which opens and closes the discharge port of the air passage chamber 6 into the freezer compartment 3, in the opening direction by heating its heat-sensitive section 281 including the bellows section 28a. It is. In addition, in other parts of this Fig. 3, reference numeral 29 denotes an operation section for controlling the temperature of the freezing room and the cold R room, an operation section for the quick freezing switch, etc., and an operation section for displaying the operation display, temperature status display, etc. A display unit, 30 is an interior light, 31 is a door switch, and 32 is a plug terminal. FIG. 4 shows a specific circuit of the temperature detection unit 18. In this FIG. 4, 33 is a refrigerator temperature detection element, 34 is a refrigerator room temperature detection element, 35 is a defrosting completion detection element (temperature detection), and 36 is a freezing room temperature detection element. Three elements 33,3
4. The signal due to the pigeon resistance change of 35 is connected to the conhalator 37, respectively.
, 38.39, the voltage dividing resistor circuits 33a, 34a,
35. The reference values va, Vb, set by a
VC is compared and given to the control unit 17 as a refrigerator room air temperature signal S, a refrigerator room air temperature signal S2, and a defrosting completion signal S4, and the resistance change of the freezing room temperature detection element 36 is detected by a comparator 4o through a voltage dividing resistor circuit. 36a is compared with the reference value Vd set by the controller 17 as a frozen room temperature signal s3.
It is designed to be given to Especially comparator 40
has a hysteresis loop 40a including a diode,
The temperature value of the signal s3 (refrigerated room temperature + air temperature) is set to be different during the rising and falling stages of the internal temperature, thereby providing a predetermined temperature difference between the stop temperature and the restart temperature of the compressor 1o. ing.

Next, the operation of the above structure (also shown in the flowcharts of FIGS. 5 and 6) will be explained. This explanation should make the structure of the refrigeration cycle control system even clearer.

(I) Normal operation Assuming that the temperature of the refrigerator compartment 2 and the freezer compartment 3 is higher than the set temperature, the control unit 17 receives this information from the refrigerator/air cooling unit 1 temperature signal S1, which is constantly received from the temperature detection unit 18. Judging from the refrigerator room air temperature signal s2 and the freezer room temperature signal S3, the compressor motor 23 and the compressor 1o are driven, the fan motor 8 is also energized, and the second control valve 15 is activated by listening to the first control valve 12. I keep it closed and continue cold NJ operation. That is, in this state, the refrigerant gas discharged from the complete tree 10 is liquefied into the condenser 11 and is supplied to the refrigerator cooler 4 and the freezer compartment main cooler 7 through the first control valve 12. to cool the inside of the refrigerator compartment 2 and the freezer compartment 3. In this case, the inside of the refrigerator compartment 2 is cooled by natural convection, and the inside of the freezer compartment 3 is cooled by forced circulation of cool air from the main freezer cooler 7 by the fan 9 (during this time, the damper 28 is open). When the temperature of the refrigerator compartment 2 drops to the set temperature, a switching operation is performed to close the first control valve 12 and open the second control valve 15 based on the refrigerator compartment air temperature signal S2 obtained by the refrigerator room temperature detection element 34. is switched to the supply state to the auxiliary cooler 5 and the main cooler 7 for the freezer compartment. When the temperature of the freezer compartment 3 drops to the set temperature in this state, the operation of the compressor 10 is stopped based on the freezer room temperature signal S3 obtained by the freezer room temperature detection element 36. During such a stop period of the compressor 10, the first control valve 1
2. Both of the second control valves 15 are maintained in the 1" state,
As a result, immediately after the compressor 10 stops, the capacitor 1
This prevents the superheated refrigerant gas staying in the condenser 11 from leaking to the cooler side and heating it, and also maintains the refrigerant in the condenser 11 in a high condensing pressure state.
0 restart efficiency as above. If the temperature of the freezing chamber 3 rises above the set range while the compressor 10 is stopped, the compressor 10 is restarted based on the freezing room temperature signal S3 at this time.

(■) Preventing cooling R air cooling power reduction A state in which the first control valve 12 opens while the compressor 10 is operating and supplies refrigerant to both the refrigerator compartment cooler 4 and the freezer compartment main cooler 7 If it continues for a long time, for example, 10 o'clock, this is determined by a timer and the first control valve 12 is closed, while the second control valve 15 is opened and the refrigerator compartment cooler 4 is closed. The refrigerant supply is stopped, and the frost adhering to the refrigerator compartment cooler 4 is removed by natural melting. As a result, refrigerant is continuously supplied to the refrigerator compartment cooler 4 for a long period of time, and the frost does not lose the opportunity to dissolve naturally. Therefore, a large amount of frost adheres to the refrigerator compartment cooler 4, which improves the cooling efficiency in the refrigerator. This prevents the situation from decreasing.

(III) Prevention of cooling stoppage in the refrigerator compartment If 30 minutes have passed since the temperature in the refrigerator compartment 2 rose to the cooling start temperature, for example 3.5° C., while the compressor 10 is stopped, the compressor 10 and the compressor motor 23
is forcibly driven by the freezing room temperature detection element 36 without depending on the freezing room temperature signal S3.

Such a forced restart of the compressor 10 (refrigerating room cooling type temperature signal S by the cooling humidity temperature detection element 33
This is done by a timer that monitors 1.

As a result, it is possible to prevent the refrigerator compartment 2 from being left in a non-operating state for a long time with a high internal temperature due to a large load placed on the refrigerator compartment 2.

(IV) Rapid cooling operation In this operation, the rapid cooling timer is manually operated to drive the compressor 10, while the first control valve 12 is closed and the second control valve 15 is closed, thereby controlling the auxiliary cooler. In this operation, the refrigerant supply to the main cooler 5 and the freezer compartment main cooler 7 is forcibly continued for the set time to rapidly cool the inside of the frozen seedlings 3. As a result, even if, for example, unfrozen food is placed in the freezer compartment 3, the food can be quickly frozen and served.

Then, when the set time h of the rapid cooling timer has elapsed, the first control valve 12 opens and the second 1lilj control valve 15 closes, forcing the flow path switching operation between the refrigerator compartment cooler 4 and the freezer. The refrigerant is supplied to the indoor main cooler 7,
This is the refrigerating room air temperature signal S by the refrigerating room temperature detection element 34.
2 until a cooling stop command is given. In this way, the temperature rise in the refrigerator compartment 2 during the rapid cooling operation period of the freezer compartment 3 is compensated for.

(V) Defrosting operation The defrosting operation of the main cooler 7 for the freezer compartment is performed as follows. That is, the defrost monitoring timer integrates the operating time of the compressor 10, and outputs a defrost start command signal when the operating time of the compressor 10 reaches a set time, for example, 48 hours. This command causes the first forced cooling operation to be performed.

(A) First forced cooling power J operation Based on the defrosting start command, the compressor motor 23 and fan motor 8 are driven and the first control valve 12 is forcibly opened to cool M seedlings 1° Refrigerant is supplied to the container 4 and the main cooler 7 for the freezer compartment. This state continues until the first control valve 12 is closed by the refrigerating room air temperature signal S2 from the refrigerating room temperature detection cord 34, whereby the refrigerating room 2 is forcedly cooled. Then, when the first control valve 12 is closed and the second control valve 15 is opened in response to the refrigerator compartment air temperature signal S2, the refrigerant is forcibly supplied to the auxiliary cooler 5 and the main cooler 7 for the freezer compartment. This state is continued for a certain period of time, for example, 15 minutes, using a dedicated timer. After this time has elapsed, the drive of the compressor 10 is stopped, and the first control valve 12 and the second control valve 15 are opened. By such a first forced cooling operation, the refrigerator compartment 2 and the freezer compartment 3 are sufficiently cooled in advance.

(B) Frost melting operation After the first forced cooling operation is finished, the frost melting operation is continued. This frost melting operation is carried out by energizing the damper driving heater 22 to cause the bellows portion 28a to be energized and opening the damper 28, and then by energizing the defrosting heater 21.

As a result, the frost adhering to the main cooler 7 for the freezer compartment is melted and removed, and since the damper 28 is closed, this frost melting operation 1"11 +-l 和IS"3<宕(: , L7 亦m 2s 7km' When the frost has finished melting, the surface temperature of the main cooler 7 for the freezer compartment suddenly drops to t-
Therefore, the control unit 17 detects this as the defrosting completion detection element 35.
The defrosting heater 21 is de-energized based on the defrosting completion signal S4 obtained. In this embodiment, especially after the defrosting heater 21 is cut off, the damper 28 is continuously kept open and the compressor 10 is kept stopped for a predetermined short period of time, for example, 5 minutes, using a timer. During this period, the water droplets that have accumulated on the surface of the main cooler 7 for the freezer compartment due to the melting of frost are allowed to flow down naturally, thereby preventing these water droplets from freezing at the start of the cooling operation.

(C) Residual heat absorption operation After the frost melting operation is completed, the damper 28 is kept closed, the fan motor 8 is also kept stopped, the compressor 10 is forcibly driven, and the second control valve 15 is opened. While the residual heat absorption operation for supplying refrigerant only to the auxiliary cooler 5 and the main cooler 7 for the freezer compartment is performed for a predetermined period of time, for example, 10 minutes, the damper 28 is also turned off at 11V' following the water droplet removal operation. The fan motor 8 is also kept in a stopped state. In this way, if the cooling operation is restarted and the damper 2B is opened and the fan motor 8 is driven at the same time as the defrosting is completed, water vapor or To prevent the inconvenience that residual heat, that is, warm air is immediately blown out into the freezer compartment 3.

CD) Second forced cooling operation After such a defrosting residual heat absorption operation, the damper 28 is opened again by the timer and the refrigerant is transferred to the auxiliary cooler 5 and the main cooler 7 for the freezer compartment while driving the fan motor 8. A second forced cooling operation is performed for about 20 minutes, for example. This forcibly cools the inside of the freezer compartment 3, which had a tendency to rise in temperature during the above-described frost melting operation and residual heat absorption operation, thereby helping to quickly recover the humidity inside the freezer compartment 3. When this 20 minute period has elapsed, the subsequent control operation is shifted to normal operation based on the freezing room cooler temperature signal S3 from the freezing room temperature detection purple sweet potato 36.

(Vl) Priority relationship between rapid cooling operation and defrosting operation In actual usage conditions, a rapid cooling command signal may be issued during defrosting operation (meaning that includes related operations before and after the actual frost melting operation), Alternatively, the opposite may occur, and in that case, describe the priority relationship below.

If the rapid cooling command signal is received during the first forced cooling operation after the defrosting command has already been generated, or during the first forced cooling operation after the residual heat absorption operation is completed, the control unit 17 Priority is given to the cooling operation, and the subsequent operation of the defrosting operation is stopped, and the state is made to wait for the defrosting command again.Then, when the rapid cooling operation is finished, the defrost monitoring timer has already set the cumulative time of compressor 0. Since the time has been reached, the above-mentioned defrosting operation is automatically started.

On the other hand, if the rapid cooling command signal is received before the defrosting operation ends. gives priority to defrosting operation and continues it as is. Then, when the defrosting operation is completed, it is stored in the control unit 17 and the rapid cooling operation (h<T) is started based on the input rapid cooling command signal.

This effectively prevents the situation where, when the frost melting operation has started and water droplets are attached to the cooling enclosure 7, if you try to perform a rapid cooling operation, the water droplets will freeze and the frost will develop significantly. This can be effectively prevented.

In the above embodiment, in order to detect the refrigerator room temperature, the air temperature detection and the temperature detection of the cooler itself are selected and one of these detection signals is used depending on the control purpose. You can treat only one of them as the refrigerator room temperature signal.6X.

〔Effect of the invention〕

According to the present invention, since an auxiliary cooler is provided in the freezer compartment, food can be placed on it for quick cooling similar to that of conventional direct cooling type, and it is also possible to cool food items on shelves and other walls of the cooler. It is possible to quickly cool food that is placed on a wall other than the wall surface with a force of 1, which is the same as that of the cold air circulation type shown in Example 7. Therefore, food in the freezer compartment can be sufficiently cooled regardless of where it is stored. Moreover, when it is desired to cool food particularly rapidly, this can be made possible by a rapid cooling operation that supplies refrigerant to both the main cooler and the auxiliary cooler for the freezer compartment. The operation is not just a simple frost melting operation, but a first forced cooling operation is performed before the frost melting operation, and a residual heat absorption operation and a second forced cooling operation are performed after the frost melting operation, so that the humidity inside the refrigerator does not increase during defrosting. Further, since the defrosting operation +lt is continued even if a rapid cooling command signal is issued during the period from the start of the frost melting operation to the end of the residual heat absorption operation, It is possible to prevent the freezing of water droplets during defrosting, to suppress the development of frost formation, and to perform effective defrosting operation.

[Brief explanation of the drawing]

The drawings relate to one embodiment of the present invention, and FIG.
Schematic longitudinal side view of the refrigerator, Figure 2 [Yo Refrigeration→Nikuru connection diagram, Figure 3 is the horizontal fFc KI I! of the control circuit. IJ diagram, Figure 4 is a wiring diagram of the temperature detection unit, Figures 5 and 6
The figure is a flowchart. In the figure, 2 is a refrigerator compartment, 3 is a freezer compartment, 4 is a cooler for the cold storage room, 5 is an auxiliary cooler, 6 is an air passage room, 7 is a main cooler, 9 is a fan, 1Q is a compressor, and 12 is a First control valve-11
5 is a second control valve, 18 is a temperature detection unit, 33 is a cooling type temperature detection element for the refrigerator compartment, 34 is a freezing room temperature detection element,
36 is a frozen room temperature detection element. Applicant Tokyo Shibaura Electric Co., Ltd. Figure 1 Figure 2 Figure 3M

Claims (1)

[Claims] 1. In a refrigerator equipped with a freezer compartment cooler consisting of an auxiliary cooler for placing food and cooling it, and a main cooler for cooling circulating air by a fan, the defrosting operation of the main cooler is performed in the freezer compartment. and a first forced cooling operation that forcibly cools the refrigerator compartment for a predetermined period of time, a frost melting operation that cuts off refrigerant supply to the main cooler and heats the main cooler, and supplies refrigerant to the main cooler while the circulating air is stopped. A residual heat absorption operation and a second forced cooling Nl operation for generating circulating air and supplying refrigerant to the cooler are sequentially performed, and the rapid cooling operation of the freezer compartment is performed in response to a rapid cooling command signal. the rapid cooling command signal is issued during each of the first and second forced cooling operations; The system is configured to shift to the rapid cooling operation, and to continue the defrosting operation if the rapid cooling command signal is issued during a period from the start of the frost melting operation to the end of the residual heat absorption operation. A refrigerator featuring