KR20220080618A - Refrigerator and control method thereof - Google Patents

Abstract

A refrigerator according to an embodiment of the present invention includes a compressor, a condenser, a switching valve connected to the outlet of the condenser, a flow path connected to a branched side of the switching valve and connected to a refrigerating compartment capillary tube and a refrigerating compartment evaporator, and a branch of the switching valve. In the refrigerator comprising: a flow path on the freezing chamber evaporator connected to the freezing chamber capillary tube and the freezing chamber evaporator connected to the other side of the refrigerator; and an outside air temperature sensor sensing a temperature, wherein the control unit includes: when the outside air temperature sensed by the outside air temperature sensor is equal to or less than a set temperature at which the refrigerant pressure inside the condenser is lowered, the freezing compartment evaporator side flow path and the refrigerating compartment evaporator side flow path; It is characterized in that by opening the switching valve so that all are communicated, the refrigerant circulation amount to the refrigerating chamber evaporator is controlled to increase.

Description

Refrigerator and control method of refrigerator { Refrigerator and control method thereof }

The present invention relates to a refrigerator and a method for controlling a refrigerator.

BACKGROUND ART In general, a refrigerator is a home appliance that can store food at a low temperature in an internal storage space that is shielded by a door. To this end, the refrigerator is configured to store the stored food in an optimal state by cooling the inside of the storage space using cold air generated through heat exchange with the refrigerant circulating in the refrigeration cycle.

Recently, refrigerators are gradually becoming larger and more multifunctional in accordance with changes in dietary habits and the trend of luxury products. .

Such a refrigerator is provided with a refrigeration cycle including a compressor, a condenser, an expansion device, and an evaporator, and can cool the interior space through heat exchange with a refrigerant circulating in the refrigeration cycle.

The refrigerator may include a refrigerating compartment and a freezing compartment, and a refrigerating compartment evaporator and a freezing compartment evaporator may be respectively disposed in the refrigerating compartment and the freezing compartment to independently cool the refrigerating compartment and the freezing compartment. In addition, the refrigerator may selectively supply the high-temperature and high-pressure refrigerant supplied from the compressor to the refrigerating compartment evaporator and the freezing compartment evaporator according to the switching of the 3-way valve to cool the refrigerating compartment and the freezing compartment. Such a refrigerator may have an independent cold air circulation structure between the refrigerating compartment and the freezing compartment, thereby enabling efficient cooling of the refrigerating compartment and the freezing compartment.

However, in the refrigerator having such a structure, when the temperature around the refrigerator is low, such as in winter, the temperature of the condenser is lowered, and thus the pressure on the condenser side is lowered. And, when the pressure on the condenser side is lowered, the refrigerant circulation amount in the refrigeration cycle is reduced, thereby causing a weak cooling problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide a refrigerator and a method for controlling a refrigerator capable of improving the weak cooling problem in a state where the external air temperature of the refrigerator is low.

It is an object of the present invention to provide a refrigerator and a refrigerator control method capable of securing defrosting quality during natural defrosting of a refrigerating compartment in a state where the outside air temperature of the refrigerator is low.

A refrigerator according to an embodiment of the present invention includes a compressor, a condenser, a switching valve connected to the outlet of the condenser, a flow path connected to a branched side of the switching valve and connected to a refrigerating compartment capillary tube and a refrigerating compartment evaporator, and a branch of the switching valve In the refrigerator comprising: a flow path on the freezing chamber evaporator connected to the freezing chamber capillary tube and the freezing chamber evaporator connected to the other side of the refrigerator; and an outside air temperature sensor sensing a temperature, wherein the control unit includes: when the outside air temperature sensed by the outside air temperature sensor is equal to or less than a set temperature at which the refrigerant pressure inside the condenser is lowered, the freezing compartment evaporator side flow path and the refrigerating compartment evaporator side flow path; By opening the switching valve so that all are communicated, the refrigerant circulation amount to the evaporator of the refrigerating compartment may be controlled to increase.

The set temperature may be 13 ℃.

a refrigerating compartment fan circulating air between the refrigerating compartment evaporator and the refrigerating compartment at one side of the refrigerating compartment evaporator; and a defrost temperature sensor sensing a temperature of the refrigerating compartment evaporator, wherein the control unit stops the compressor during a natural defrosting operation of the refrigerating compartment, and the refrigerating compartment fan is can be driven,

The natural defrost operation includes a primary defrost operation in which the natural defrost operation is performed until the temperature of the defrost temperature sensor reaches a first defrost completion temperature, and after the primary defrost operation is completed, the defrost temperature sensor and a secondary defrost operation in which the natural defrost operation is performed until the temperature reaches a second defrost completion temperature, and after the end of the primary defrost operation, the selector valve operates the refrigerating compartment evaporator until the secondary defrost operation is started. An additional cooling operation of cooling the refrigerating compartment by opening the side flow path may be included.

In the additional cooling operation, the compressor may perform an additional cooling operation driven with maximum cooling power.

The secondary defrost operation may be performed for a longer time than the primary defrost operation.

The detection temperature of the suggested temperature sensor for the end of the second defrost operation may be set higher than the detection temperature of the defrost temperature sensor for the end of the first defrost operation.

In the control method of a refrigerator according to an embodiment of the present invention, a freezing compartment evaporator for cooling the freezing compartment and a refrigerating compartment evaporator for cooling the refrigerating compartment are connected in parallel, and by the operation of a switching valve, the freezing compartment evaporator side flow path and the refrigerating compartment evaporator side flow path are selectively selected determining, through an outside air temperature sensor, that an outside air temperature around a refrigerator is installed in a refrigerator that supplies a refrigerant is equal to or less than a set temperature at which the refrigerant pressure inside the condenser is lowered; and operating the switching valve so that both the flow path on the evaporator side of the refrigerating compartment and the flow path on the evaporator side of the freezing compartment are opened when the outside air temperature is equal to or less than a set temperature.

When a natural defrost signal for defrosting of the refrigerating compartment evaporator is input while the switching valve is operated so that both the refrigerating compartment evaporator side flow path and the freezing compartment evaporator side flow path are open It may include blocking the flow path; and performing a natural defrosting operation by circulating cold air between the refrigerating compartment evaporator and the refrigerating compartment by driving the refrigerating compartment fan.

The natural defrost operation may be performed a plurality of times until the temperature sensed by the defrost temperature sensor reaches the defrost completion temperature.

According to the refrigerator according to the embodiment of the present invention, the following effects can be expected.

The refrigerator according to an embodiment of the present invention cools the refrigerating compartment and the freezing compartment by supplying refrigerant to the refrigerating compartment evaporator and the freezing compartment evaporator, respectively, by the operation of the switching valve. And, when the outside air temperature around the refrigerator falls below the set temperature as in winter by the outside air temperature sensor, the switching valve opens both the refrigerating compartment evaporator side flow path and the freezing compartment evaporator side flow path to control the flow rate of refrigerant flowing into the refrigerating compartment evaporator. There is an advantage in that it is possible to prevent weak cooling of the refrigerating chamber from occurring by securing it.

And, when a natural defrost operation is performed to remove frost on the refrigerating compartment evaporator while the switching valve opens both the refrigerating compartment evaporator side flow path and the freezing compartment evaporator side flow path, the switching valve closes the refrigerating compartment evaporator side flow path The supply of cold air to the evaporator is blocked. In this state, the refrigerating compartment fan is driven to circulate air between the refrigerating compartment and the refrigerating compartment evaporator, and it is possible to remove the frost on the refrigerating compartment evaporator. Therefore, even if a separate defrost heater is not provided, there is an advantage that effective natural defrosting is possible even at a low temperature such as in winter, and a reduction effect of power consumption can be expected.

In addition, the natural defrost operation may be divided into a plurality of times like the primary defrost operation and the secondary defrost operation, and it is possible to prevent excessive increase in the temperature inside the refrigerating compartment during defrosting, thereby further reducing power consumption.

And, by performing an additional cooling operation in which the compressor is driven with the maximum cooling power between the first defrosting operation and the second defrosting operation, an excessive increase in the temperature of the refrigerating chamber is prevented within a range that does not reduce the defrost efficiency, thereby further reducing power consumption. can be reduced

1 is a diagram schematically showing the structure of a refrigerator according to an embodiment of the present invention.
2 is a circuit diagram illustrating a refrigerant flow in the refrigerator.
3 is a block diagram illustrating a flow of a control signal of the refrigerator.
4 is a flowchart sequentially illustrating the operation of the refrigerator.
5 is a graph illustrating a change in the temperature of the refrigerating compartment according to time during operation of the refrigerator according to the refrigerator control method according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing an embodiment of the present invention, a detailed description of a related known configuration or its function will be omitted if it is determined that it is obvious to those skilled in the art.

In addition, the embodiment of the present invention will be described as an example of a bottom-freeze type refrigerator in which a freezing compartment is provided below for convenience of explanation and understanding, and the present invention is not limited to the shape of the refrigerator, and the refrigerator compartment evaporator and the freezer compartment evaporator are It is provided in advance, and the refrigerating compartment is applicable to all types of refrigerators in which a defrosting operation is performed by natural defrosting.

For the convenience of explanation and understanding, we would like to define the direction. Hereinafter, with respect to the floor on which the refrigerator is installed, a direction toward the floor may be referred to as downward, and a direction toward the opposite high surface of the cabinet may be referred to as an upper direction. In addition, a direction toward the door may be referred to as a front direction, and a direction toward the inside of the cabinet with respect to the door may be referred to as a rear direction. And when you want to talk about an undefined direction, you can define the direction based on each drawing and explain it.

1 is a view schematically showing the structure of a refrigerator according to an embodiment of the present invention.

As shown in the drawing, the refrigerator 1 may include a cabinet 10 forming a storage space and a door 20 opening and closing the opened front of the cabinet 10 .

The storage space inside the cabinet 10 may be partitioned up and down by a barrier 11 , the refrigerating compartment 12 may be formed at the upper side, and the freezing compartment 30 may be formed at the lower side. In addition, the door 20 may include a refrigerating compartment door 21 for opening and closing the refrigerating compartment 12 and a freezing compartment door 22 for opening and closing the freezing compartment 30 .

In addition, a machine room 14 formed separately from the refrigerating compartment 12 and the freezing compartment 30 may be formed in the corner portions of the rear and lower surfaces of the cabinet 10 . A compressor 141 , a condenser 142 , and a condenser fan 143 constituting a refrigeration cycle may be provided in the machine room 14 . In addition, at least one of a refrigerating compartment capillary 126 and a freezing compartment capillary 136 connected to the branched output side of the switching valve 15 may be disposed in the machine compartment 14 . The machine room 14 may communicate with an external space in which the refrigerator 1 is installed. Accordingly, external air may be introduced into the machine room 14 by the condenser fan 143 , and the introduced air may be discharged to the outside after heat dissipation of the condenser 142 and cooling of the compressor 141 .

A refrigerating compartment rear plate 121 may be provided on a rear surface of the refrigerating compartment 12 . The refrigerating compartment rear plate 121 may form a refrigerating compartment heat exchange space 120 in which the refrigerating compartment evaporator 124 and the refrigerating compartment fan 125 may be disposed at the rear. In addition, a discharge port 122 and a suction port 123 may be formed in the refrigerating compartment rear plate 121 .

Accordingly, when the refrigerating compartment fan 125 is driven, the air sucked through the suction port 123 is cooled while passing through the refrigerating compartment evaporator 124 and is then supplied to the refrigerating compartment 12 through the discharge port 122. The refrigerating compartment 12 may be cooled.

In addition, a freezer compartment rear plate 131 may be provided on the rear surface of the freezing compartment 30 . The freezing compartment rear plate 131 may form a freezing compartment heat exchange space 130 in which the freezing compartment evaporator 134 and the freezing compartment fan 135 may be disposed at the rear. In addition, an outlet 132 and an inlet 133 may be formed in the freezing compartment rear plate 131 .

Accordingly, when the freezing compartment fan 135 is driven, the air sucked through the suction port 133 is cooled while passing through the freezing compartment evaporator 134 , and then is supplied to the refrigerating compartment 12 through the discharge port 132 . The freezing chamber 30 may be cooled.

Meanwhile, in the refrigerator 1 , a refrigeration cycle may be operated so that the refrigerating compartment 12 and the freezing compartment 30 can maintain set temperatures.

Hereinafter, the flow path of the refrigerant in the refrigerator 1 and the flow of control signals for cooling the refrigerating compartment 12 and the freezing compartment 30 will be described.

2 is a circuit diagram illustrating a refrigerant flow in the refrigerator. 3 is a block diagram showing the flow of a control signal of the refrigerator.

As shown in the drawing, a switching valve 15 may be provided at the outlet side of the condenser 142 connected to the compressor 141 . The switching valve 15 may be configured to selectively supply the refrigerant discharged from the condenser to the refrigerating compartment evaporator 124 and the freezing compartment evaporator 134 . The switching valve 15 may be called a three-way valve, a three-way valve, or a three-way valve.

The inlet of the selector valve 15 is connected to the outlet of the condenser 142 , and the outlet of the selector valve 15 is branched and faces the refrigerating compartment evaporator 124 , the refrigerating compartment evaporator flow path 161 and the freezing compartment evaporator. (134) may be respectively connected to the flow path 162 on the evaporator side of the freezing compartment.

The selector valve 15 may be controlled by the control unit 30 , and may close or open all of the flow paths toward the refrigerating compartment evaporator 124 and the freezing compartment evaporator 134 , or selectively open any one according to need. can be closed

The refrigerating compartment capillary tube 126 and the refrigerating compartment evaporator 124 may be connected to the refrigerating compartment evaporator side flow path 161 connected to the branched outlet of the switching valve 15 . Accordingly, the refrigerant guided to the flow path 161 on the refrigerating compartment evaporator side passes through the refrigerating compartment capillary tube 126 and the refrigerating compartment evaporator 124 in turn due to the switching of the switching valve 15 . In addition, the outlet of the refrigerating compartment evaporator 124 is connected to the inlet of the compressor 141 , so that the refrigerant discharged from the refrigerating compartment evaporator 124 may be recovered to the compressor 141 .

In addition, the freezing chamber capillary tube 136 and the freezing chamber evaporator 134 may be connected to the freezing chamber evaporator side flow path 162 connected to the outlet of the switching valve 15 . Accordingly, the refrigerant guided to the freezing chamber evaporator side flow path 162 by the switching of the switching valve 15 passes through the freezing chamber capillary tube 136 and the freezing chamber evaporator 134 sequentially. In addition, the outlet of the freezing compartment evaporator 134 may be connected to the inlet of the compressor 141 so that the refrigerant discharged from the freezing compartment evaporator 134 may be recovered to the compressor 141 .

Meanwhile, a check valve 137 may be provided at the outlet of the freezing chamber evaporator 134 . The check valve 137 may be opened only in a direction from the outlet of the freezing compartment evaporator 134 toward the inlet of the compressor 141 , and thus the refrigerant discharged from the freezing compartment evaporator 134 is directed toward the compressor 141 . flow, and the refrigerant discharged from the refrigerating compartment evaporator 124 and directed to the compressor 141 may be prevented from flowing back into the freezing compartment evaporator 134 due to a pressure difference.

When the compressor 141 is driven, the refrigerant can be supplied to the refrigerating compartment evaporator 124 and/or the freezing compartment evaporator 134 according to the selective opening of the flow path of the switching valve 15 . At this time, the condenser fan 143 is driven to dissipate heat from the condenser 142, and the refrigerating compartment fan 125 and the freezing compartment fan 135 are driven to cool the refrigerating compartment 12 and the freezing compartment 30. can

Meanwhile, the refrigerating compartment 12 and the freezing compartment 30 may be provided with a refrigerating compartment temperature sensor 31 and a freezing compartment temperature sensor 32 for sensing the temperatures of the refrigerating compartment 12 and the freezing compartment 30 , respectively. Accordingly, the controller 30 may cool the refrigerating compartment 12 and the freezing compartment 30 so that the refrigerating compartment 12 and the freezing compartment 30 can maintain set temperatures.

In detail, the control unit 30 opens the switching valve 15 to communicate with the refrigerating compartment evaporator side flow path 161 until the temperature of the refrigerating compartment temperature sensor 31 reaches a set refrigerating compartment temperature, and the compressor ( 141 ) and the refrigerating compartment fan 125 may be operated to cool the refrigerating compartment 12 . In addition, the control unit 30 opens the switching valve 15 to communicate with the freezing compartment evaporator side flow path 162 until the temperature of the freezing compartment temperature sensor 32 reaches the set freezing compartment temperature, and the compressor ( 141 ) and the freezer compartment fan 135 may be operated to cool the freezing compartment 30 .

According to the switching of the switching valve 15, the refrigerant can be supplied to the refrigerating compartment evaporator side flow path 161 and the freezing compartment evaporator side flow path 162, and the refrigerating compartment 12 and the freezing compartment 30 are alternately respectively. can be cooled.

On the other hand, the refrigerator 1 may include an outdoor temperature sensor 33 capable of measuring a temperature around the refrigerator 1 is installed. The outdoor temperature sensor 33 may be provided on one side of the cabinet 10 , and may sense the temperature of the external space in which the refrigerator 1 is installed, that is, the outdoor temperature. The outside air temperature is a temperature at a location adjacent to the refrigerator 1 , and may be referred to as an ambient temperature.

The controller 30 may control the operation of the refrigeration cycle according to the temperature sensed by the outdoor temperature sensor 33 . When the temperature of the outside air is below the set temperature, a weak cooling problem may occur in the refrigerating compartment 12 , and in order to solve this problem, the control unit 30 performs the low-temperature mode operation. The set temperature for the low-temperature mode operation may be set to a temperature of 13° C. or less, which is a temperature at which a substantial pressure drop occurs in the condenser 142 . The low-temperature mode operation may be referred to as a winter mode operation.

On the other hand, in the refrigerator 1, moisture from food during operation and moisture from the door 20 when the door 20 is opened and closed causes frost to form on the refrigerating compartment evaporator 124 and the freezer compartment evaporator 134, resulting in a decrease in cooling ability. may occur. Accordingly, the controller 30 may perform a defrosting operation to remove the frost adhering to the refrigerating compartment evaporator 124 and the freezing compartment evaporator 134 .

In the case of the freezing chamber evaporator 134, the temperature is very low, and therefore, in order to remove the attached frost, a separately provided freezing chamber defrost heater 138 may be operated to remove the frost.

On the other hand, in the case of the refrigerating compartment evaporator 124, the temperature is relatively high, and without a separate defrost heater, the air in the refrigerator is forced to circulate while the compressor 141 is stopped to prevent frost attached to the refrigerating compartment evaporator 124. can be removed As described above, the operation of removing the frost using the air in the refrigerating compartment 12 without using the defrosting heater may be referred to as a natural defrosting operation.

In addition, the control unit 30 can effectively perform an operation for natural defrosting of the refrigerating compartment evaporator 124 in a state where the ambient temperature is below a set temperature, such as in winter.

For the natural defrosting operation, a defrosting temperature sensor 34 may be provided at one side of the refrigerating compartment evaporator 124 . The defrost temperature sensor 34 may measure the temperature of the refrigerating compartment evaporator 124 or a temperature of a position adjacent to the refrigerating compartment evaporator 124 to provide temperature information necessary for starting and ending the defrosting operation. Since the defrost temperature sensor 34 measures the temperature of the refrigerating compartment evaporator 124, it may be referred to as an evaporator temperature sensor.

Hereinafter, the operation of the refrigerator 1 having the above structure and the natural defrosting operation will be described with reference to the drawings.

4 is a flowchart sequentially illustrating the operation of the refrigerator.

As shown in the drawing, the control unit 30 controls the refrigerating compartment 12 and the freezing compartment 30 to maintain a constant temperature according to the temperature input from the refrigerating compartment temperature sensor 31 and the freezing compartment temperature sensor 32 in the refrigeration cycle. to control the operation of

That is, when the temperature detected by the refrigerating compartment temperature sensor 31 is not satisfied, the switching valve 15 is switched to the refrigerating compartment evaporator side flow path 161 and the compressor 141 and the refrigerating compartment fan 125 are driven. can do. The refrigerating compartment 12 may be cooled by the cold air provided from the refrigerating compartment evaporator 124 until a preset refrigerating compartment temperature is satisfied.

In the case of the refrigerating compartment 12 , since the door 20 is frequently opened and closed frequently, temperature dissatisfaction is frequent, and rapid cooling is possible, a cooling operation may be performed in preference to the freezing compartment 30 . Accordingly, when the temperature of the refrigerating compartment 12 is satisfied, the temperature of the freezing compartment 30 may be sensed and the cooling operation of the freezing compartment 30 may be performed.

When the temperature sensed by the freezing chamber temperature sensor 32 is not satisfied while the refrigerating chamber temperature is satisfied, the switching valve 15 is switched to the freezing chamber evaporator side flow passage 162, and the compressor 141 and the freezing chamber The fan 135 may be driven. The freezing chamber 30 may be cooled by the cold air provided from the freezing chamber evaporator 134 until a preset freezing chamber temperature is satisfied.

As described above, the operation of the refrigerating compartment 12 and the freezing compartment 30 to satisfy the set temperature may be referred to as a general operation. [S100]

Meanwhile, when the temperature sensed by the outdoor temperature sensor 33 is lower than the set temperature during the normal operation, low-temperature operation (winter operation) is performed.

In detail, the outside air temperature sensor 33 senses the outside air temperature around the refrigerator 1 while the refrigerator 1 is being operated, and the controller 30 compares the sensed outside air temperature with a set temperature. At this time, when the outside air temperature is below a set temperature that may affect the efficiency of the condenser 142 , the control unit 30 performs a low-temperature operation instead of a normal operation. In this case, the set temperature may be 13 ℃. Of course, the set temperature may vary according to the specifications of the refrigeration cycle, and may be generally understood as a temperature corresponding to the temperature of the winter season. [S210]

When the temperature around the refrigerator 1 is low as in the winter season, the temperature of the condenser 142 may be lowered and the refrigerant pressure inside the condenser 142 may be lowered. During supply, the pressure difference between the input side and the output side of the condenser is reduced, so that the circulation amount of the refrigerant is reduced, which may cause a problem that the refrigerating compartment 12 is in a weak cooling state.

To solve this problem, when the outside air temperature is below the set temperature, the switching valve 15 opens both the refrigerating compartment evaporator side flow path 161 and the freezing compartment evaporator side flow path 162 to increase the flow rate of the circulating refrigerant. make it

That is, the switching valve 15 may open all of the output sides so that even the refrigerant of the freezing compartment evaporator 134 can be circulated, and the refrigerating compartment evaporator 124 can generate sufficient cooling power. When the switching valve 15 opens both the refrigerating compartment evaporator side flow path 161 and the freezing compartment evaporator side flow path 162 , the refrigerating compartment fan 125 is driven to cool the refrigerating compartment 12 . [S220]

Meanwhile, when the defrosting operation condition of the refrigerating compartment 12 is satisfied in the low-temperature operation state, the control unit 30 inputs the defrosting operation of the refrigerating compartment 12 . The defrosting operation condition may be set in consideration of the operating time of the refrigerator 1 , the number of times the door 20 is opened and closed, and the temperature of the evaporator. In particular, the refrigerating compartment 12 performs a natural defrosting operation instead of a defrosting operation using a heater in order to reduce power consumption.

In the case of such a natural defrosting operation, if the length of the refrigerating chamber evaporator 124 is longer in the left and right direction than in the vertical direction, the long heater can be omitted. Significant savings can be expected. [S230]

When a defrosting operation of the refrigerating compartment 12 is input from the control unit 30 , the switching valve 15 closes the flow path 161 on the refrigerating compartment evaporator side to block the supply of cold air to the refrigerating compartment evaporator 124 . By blocking the supply of cold air to the refrigerating compartment evaporator 124 , the temperature of the refrigerating compartment evaporator 124 is prevented from falling or being maintained, thereby creating an environment in which natural defrosting can be performed. [S240]

In this state, the compressor 141 may be stopped, and the refrigerating compartment fan 125 may be driven. When the refrigerating compartment fan 125 is driven, the air inside the refrigerating compartment 12 is supplied to the refrigerating compartment evaporator 124 to perform a natural defrosting operation.

The air inside the refrigerating compartment 12 may be continuously supplied to the refrigerating compartment evaporator 124 by the refrigerating compartment fan 125 at a zero temperature. Accordingly, the temperature of the refrigerating compartment evaporator 124 increases due to the supply of air inside the refrigerating compartment 12 , and frost formed on the refrigerating compartment evaporator 124 may be removed. In addition, when the refrigerating compartment fan 125 is operated at a high speed, the frost on the surface of the refrigerating compartment evaporator 124 can be more effectively removed along with an increase in the temperature of the refrigerating compartment evaporator 124 . [S250]

When the temperature sensed by the defrost temperature sensor 34 reaches the defrost completion temperature through the natural defrost operation, the controller 30 determines the defrost completion. That is, the natural defrost operation may be performed until the defrost completion temperature is input from the defrost temperature sensor 34, and when the defrost completion temperature is inputted from the defrost temperature sensor 34, the natural defrost operation is completed. . When the natural defrosting operation is completed, the control unit 30 returns to step S100 and performs the cooling operation of the refrigerating compartment 12 and the freezing compartment 30 again. [S260]

Meanwhile, an example of the natural defrosting operation based on the temperature change of the refrigerator 1 will be described again with reference to the drawings.

FIG. is a graph showing changes in the temperature of the refrigerating compartment according to time during operation of the refrigerator according to the refrigerator control method according to an embodiment of the present invention.

As shown in the drawing, for cooling the refrigerating compartment 12, the switching valve 15 opens the flow path 161 on the evaporator side of the refrigerating compartment, and turns on and off the compressor 141 and the refrigerating compartment fan in the refrigerating compartment. (12) can be kept constant at the set refrigerating compartment temperature. Also, when the natural defrosting operation of the refrigerating compartment evaporator 124 is input during the cooling operation of the refrigerating compartment 12 , the control unit 30 controls to perform the natural defrosting operation.

On the other hand, the natural defrosting operation may be performed by dividing the operation into a plurality of sections. If the natural defrost operation is continued for a long period of time, the temperature of the evaporator ( ) may increase excessively. , it is possible to restart the natural defrost operation after temporarily cooling the inside of the furnace.

For example, the natural defrost operation may be performed by being divided into a primary defrost operation T1 and a secondary defrost operation T2, and rapid cooling is performed between the primary defrost operation T1 and the secondary defrost operation T2. Driving may be carried out.

In detail, when a natural defrost operation is input from the control unit 30, the flow path 161 on the evaporator side of the refrigerating compartment is closed by the switching of the switching valve 15, the compressor 141 is stopped, and the evaporator fan () While this is driven, the primary defrost operation T1 may be started.

While the first defrosting operation T1 is started, the temperature of the refrigerating compartment 12 is continuously increased. Also, the air in the refrigerating compartment 12 may be continuously supplied to the refrigerating compartment evaporator 124 .

When a predetermined time elapses after the first defrosting operation T1 is started, the first phase change time P1 is reached, so that the frost formed on the refrigerating compartment evaporator 124 can be substantially removed. For example, the first phase change time P1 is approximately 1 hour and 19 minutes after the first defrost operation T1 starts, and the first phase change time P1 is implanted in the refrigerator compartment evaporator 124 after the first phase change time P1. The frost will melt. That is, the temperature of the refrigerating compartment evaporator 124 input from the defrost temperature sensor 34 is maintained constant until the first phase change time P1, and rapidly rises after the first phase change time P1. will do

And, when the temperature input by the defrost temperature sensor 34 reaches the first defrost completion temperature D1, the first defrost operation T1 is terminated. For example, the first defrost completion temperature D1 may be approximately 3°C. In addition, the first defrosting operation T1 may be performed for approximately 2 hours.

When the first defrosting operation T1 is finished, the controller 30 causes the switching valve 15 to open the flow path 161 on the evaporator side of the refrigerating compartment, and drives the compressor 141 and the refrigerating compartment fan 125 . A rapid cooling operation for cooling the refrigerating chamber 12 is performed.

Through the rapid cooling operation, the refrigerating compartment evaporator 124 reaches a set temperature. At this time, the maximum refrigerant flow rate is supplied to the refrigerating compartment evaporator 124 to rapidly lower the temperature of the refrigerating compartment evaporator 124 . During the rapid cooling operation T3, the temperature of the refrigerating compartment evaporator 124 may be significantly lower than that in the normal operation. For example, the refrigerating compartment evaporator 124 may be cooled to approximately -21°C, and a rapid cooling operation may be performed for approximately 22 minutes.

When the rapid cooling operation T3 is finished, the control unit 30 causes the switching valve 15 to close the flow path 161 on the evaporator side of the refrigerating compartment again, and causes the compressor 141 to stop. In this state, the second defrosting operation T2 is started by driving the refrigerating compartment fan 125 .

In detail, while the second defrosting operation T2 is started, the temperature of the refrigerating compartment 12 is continuously increased again. Also, the air in the refrigerating compartment 12 may be continuously supplied to the refrigerating compartment evaporator 124 .

In addition, when a predetermined time elapses after the second defrosting operation T2 is started, the second phase change time P2 is reached, so that the frost formed on the refrigerating compartment evaporator 124 can be substantially removed. For example, the second phase change time P2 is approximately 1 hour and 54 minutes after the secondary defrost operation T2 starts, and the frost formed on the refrigerating compartment evaporator 124 after the second phase change time is melted. do. That is, the temperature of the refrigerating compartment evaporator 124 input from the defrost temperature sensor 34 is kept constant from the start of the second defrosting operation T2 until the second phase change time P2, and the second It increases rapidly after the phase change time P2.

And, when the temperature input by the defrost temperature sensor 34 reaches the second defrost completion temperature D2, the secondary defrost operation T2 is terminated. For example, the second defrosting completion temperature D2 may be approximately 5°C. In addition, the second defrosting operation T2 may be performed for approximately 4 hours and 10 minutes.

As such, the second defrosting operation T2 may be started at a relatively lower temperature of the refrigerating compartment evaporator 124 , and thus may be performed for a relatively longer time than the first defrosting operation T1 . In addition, the second phase change time P2 may also be longer than the first phase change time P1 .

In addition, the secondary defrost operation T2 is a last operation for finally ending the natural defrost operation, and thus the second defrost completion temperature D2 may be a temperature for the natural defrost operation to end.

When the secondary defrosting operation T2 is completed, the natural defrosting operation may be finally terminated, and a rapid cooling operation may be performed again after the natural defrosting operation is terminated. Then, after the rapid cooling operation, the switching valve 15 opens the oil path 161 on the evaporator side of the refrigerating compartment and turns on/off the compressor 141 and the refrigerating compartment fan 125 to set the temperature at which the refrigerating compartment 12 is set. can be maintained.

Claims (10)

A compressor, a condenser, a selector valve connected to the outlet of the condenser, a flow path on the refrigerating compartment evaporator side connected to a branched side of the selector valve and to which a refrigerating compartment capillary and a refrigerating compartment evaporator are connected, and the other branched side of the selector valve connected to the freezing compartment capillary and the freezing compartment A refrigerator comprising: an evaporator-side flow path in a freezer compartment to which an evaporator is connected;
It includes an outdoor temperature sensor for detecting the ambient temperature in the vicinity of which the refrigerator is installed,
The control unit is
When the outside air temperature sensed by the outside air temperature sensor is equal to or less than a set temperature at which the refrigerant pressure inside the condenser is lowered, the switching valve is opened to communicate with both the freezing compartment evaporator side flow path and the refrigerating compartment evaporator side flow path, and A refrigerator that controls the refrigerant circulation to increase.
The method of claim 1,
The set temperature is 13 ℃ refrigerator.
The method of claim 1,
On one side of the refrigeration chamber evaporator,
a refrigerating compartment fan for circulating air between the refrigerating compartment evaporator and the refrigerating compartment;
and a defrost temperature sensor for sensing the temperature of the refrigerating chamber evaporator,
The control unit is
A refrigerator configured to stop the compressor during a natural defrosting operation of the refrigerating compartment and drive the refrigerating compartment fan while the switching valve blocks a flow path at the evaporator side of the refrigerating compartment.
4. The method of claim 3,
The natural defrost operation is
a first defrost operation of performing the natural defrost operation until the temperature of the defrost temperature sensor reaches a first defrost completion temperature;
After the end of the first defrosting operation, a secondary defrosting operation of performing the natural defrosting operation until the temperature of the defrosting temperature sensor reaches a second defrosting completion temperature,
and an additional cooling operation in which the switching valve cools the refrigerating compartment by opening the flow path of the refrigerating compartment evaporator after the end of the first defrosting operation and before the beginning of the second defrosting operation.
5. The method of claim 4,
A refrigerator performing an additional cooling operation in which the compressor is driven with a maximum cooling power in the additional cooling operation.
6. The method of claim 5,
A refrigerator in which the second defrost operation is performed for a longer time than the first defrost operation.
5. The method of claim 4,
A refrigerator in which a detection temperature of the suggested temperature sensor for terminating the second defrosting operation is set higher than a detection temperature of the defrosting temperature sensor for terminating the first defrosting operation.
In a refrigerator in which a freezer compartment evaporator for cooling the freezing compartment and a refrigerating compartment evaporator for cooling the refrigerating compartment are connected in parallel and selectively supplying refrigerant to the freezing compartment evaporator side flow path and the refrigerating compartment evaporator side flow path by the operation of a switching valve,
determining, through an outdoor temperature sensor, that the ambient temperature in which the refrigerator is installed is less than or equal to a set temperature at which the refrigerant pressure inside the condenser is lowered;
and operating the switching valve to open both the flow path on the evaporator side of the refrigerating compartment and the flow path on the evaporator side of the freezing compartment when the outside air temperature is equal to or less than a set temperature.
9. The method of claim 8,
In a state in which the switching valve is operated so that both the flow path on the evaporator side of the refrigerating compartment and the flow path on the side of the evaporator of the freezing compartment are opened,
When a natural defrost signal for defrosting the refrigerating compartment evaporator is input, stopping the compressor and blocking the flow path of the refrigerating compartment evaporator by the switching valve; and
and performing a natural defrosting operation by circulating cold air between the refrigerating compartment evaporator and the refrigerating compartment by driving the refrigerating compartment fan.
10. The method of claim 9,
The natural defrost operation is a control method of a refrigerator that is performed a plurality of times until the temperature detected by the defrost temperature sensor reaches the defrost completion temperature.

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