Refrigerator and control method of refrigerator

Abstract

A refrigerator includes a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator, and a fan configured to supply air cooled by the evaporator to the storage compartment. The refrigerator identifies an index value for detecting a defrost condition based on temperature information of the storage compartment and temperature information of the evaporator recorded at a first time point, and temperature information oaf the storage compartment and temperature information of the evaporator recorded at a second time point, and identifies whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and operate the defrost heater based on identifying that the defrost condition is satisfied.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation application of International Application No. PCT / KR2023 / 020486, filed on Dec. 13, 2023, which claims priority to Korean Patent Application No. 10-2023-0020982, filed on Feb. 16, 2023, in the Korean Intellectual Property Office, the disclosures of which are incorporated by reference herein in their entireties.BACKGROUND1. Field

[0002] The disclosure relates to a refrigerator that may efficiently operate a defrost heater and a method for controlling the refrigerator.2. Description of Related Art

[0003] A refrigerator is a device for storing items such as food, beverages, etc., for a long period without spoilage, and the refrigerator includes a plurality of storage compartments (e.g., a refrigerating compartment, a freezing compartment, a temperature conversion compartment) capable of storing the items.

[0004] The refrigerator repeatedly performs a cooling cycle of compression-condensation-expansion-evaporation of a refrigerant to maintain the temperature of the storage compartment at a set target temperature. That is, the refrigerator supplies each storage compartment with air cooled by an evaporator corresponding to each storage compartment based on a target temperature of each storage compartment, thereby maintaining each storage compartment at its target temperature.

[0005] Water vapor introduced into the refrigerator from outside at room temperature, or water vapor evaporated from food stored in the refrigerator may form frost on an outer surface of the evaporator at a low temperature due to a temperature difference. In addition, frost on the evaporator's surface may reduce heat exchange efficiency, causing decreased cooling efficiency and increased power consumption.SUMMARY

[0006] Provided is a refrigerator that may efficiently remove frost formed on an evaporator, and a method for controlling the refrigerator.

[0007] Further, provided is a refrigerator that may economically operate a defrost heater, and a method for controlling the refrigerator.

[0008] Technical aspects that can be achieved by the disclosure are not limited to the above-mentioned aspects, and other technical aspects not mentioned will be clearly understood by one of ordinary skill in the technical art to which the disclosure belongs from the following description.

[0009] According to an aspect of the disclosure, there is provided a refrigerator including a storage compartment; an evaporator; a defrost heater provided around the evaporator; a compressor configured to compress a refrigerant discharged from the evaporator; a fan configured to supply air cooled by the evaporator to the storage compartment; at least one memory storing instructions and configured to record temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and at least one processor, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to: identify an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point; identify whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and operate the defrost heater based on identifying that the defrost condition is satisfied.

[0010] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to: identify a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point; identify a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; and identify the index value based on the difference value between the first value and the second value.

[0011] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and wherein the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0012] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to, based on a presence of a plurality of past time points that satisfy the defined condition, identify an oldest time point among the plurality of past time points as the second time point.

[0013] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to, based on an absence of a past time point that satisfies the defined condition, omit identifying the index value corresponding to the first time point.

[0014] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to delete oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

[0015] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to identify the index value at the defined time intervals, based on an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

[0016] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

[0017] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, and a defined number of consecutive index values identified at the defined time intervals all being greater than a threshold value.

[0018] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to operate the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, based on identifying that the defrost condition is not satisfied.

[0019] According to an aspect of the disclosure, there is provided a method for controlling a refrigerator including a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator; and a fan configured to supply air cooled by the evaporator to the storage compartment, the method including: recording temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; identifying an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point; identifying whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and operating the defrost heater based on identifying that the defrost condition is satisfied.

[0020] The identifying of the index value may include: identifying a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point; identifying a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; and identifying the index value based on the difference value between the first value and the second value.

[0021] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and wherein the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0022] The method may include, based on presence of a plurality of past time points that satisfy the defined condition, identifying an oldest time point among the plurality of past time points as the second time point.

[0023] The method may include: based on an absence of a past time point that satisfies the defined condition, omitting the identifying of the index value corresponding to the first time point.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other aspects, features, and advantages of embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0025] FIG. 1 is an external view of a refrigerator according to an embodiment of the disclosure;

[0026] FIG. 2 is a cross-sectional view of a refrigerator according to an embodiment of the disclosure;

[0027] FIG. 3 and FIG. 4 are diagrams for illustrating a cooling device of a refrigerator according to an embodiment of the disclosure;

[0028] FIG. 5 is an example of a control block diagram of a refrigerator according to an embodiment of the disclosure;

[0029] FIG. 6 is a flowchart illustrating an example of a method for controlling a refrigerator according to an embodiment of the disclosure;

[0030] FIG. 7 is a diagram illustrating an example of a method for controlling a refrigerator over time according to an embodiment of the disclosure;

[0031] FIG. 8 illustrates an example of predetermined information recorded by a refrigerator according to an embodiment of the disclosure;

[0032] FIG. 9 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure; and

[0033] FIG. 10 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure.DETAILED DESCRIPTION

[0034] Various embodiments of the disclosure and terms used herein are not intended to limit the technical features described herein to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of the corresponding embodiments.

[0035] In describing of the drawings, similar reference numerals may be used for similar or related elements.

[0036] The singular form of a noun corresponding to an item may include one or more of the items unless clearly indicated otherwise in a related context.

[0037] In the disclosure, phrases, such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one or all possible combinations of the items listed together in the corresponding phrase among the phrases.

[0038] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0039] Terms such as “1st”, “2nd”, “primary”, or “secondary” may be used simply to distinguish an element from other elements, without limiting the element in other aspects (e.g., importance or order).

[0040] Further, as used in the disclosure, the terms “front”, “rear”, “top”, “bottom”, “side”, “left”, “right”, “upper”, “lower”, and the like are defined with reference to the drawings, and are not intended to limit the shape and position of any element.

[0041] It will be understood that when the terms “includes”, “comprises”, “including”, and / or “comprising” are used in the disclosure, they specify the presence of the specified features, figures, steps, operations, components, members, or combinations thereof, but do not preclude the presence or addition of one or more other features, figures, steps, operations, components, members, or combinations thereof.

[0042] When a given element is referred to as being “connected to”, “coupled to”, “supported by” or “in contact with” another element, it is to be understood that it may be directly or indirectly connected to, coupled to, supported by, or in contact with the other element. When a given element is indirectly connected to, coupled to, supported by, or in contact with another element, it is to be understood that it may be connected to, coupled to, supported by, or in contact with the other element through a third element.

[0043] It will also be understood that when an element is referred to as being “on” another element, it may be directly on the other element or intervening elements may also be present.

[0044] A refrigerator according to an embodiment of the disclosure may include a main body.

[0045] The “main body” may include an inner case, an outer case positioned outside the inner case, and an insulation provided between the inner case and the outer case.

[0046] The “inner case” may include a case, a plate, a panel, or a liner forming a storage compartment (also referred to as a storage room). The inner case may be formed as one body, or may be formed by assembling a plurality of plates together. The “outer case” may form an appearance of the main body, and be coupled to an outer side of the inner case such that the insulation is positioned between the inner case and the outer case.

[0047] The “insulation” may insulate an inside of the storage compartment from an outside of the storage compartment to maintain inside temperature of the storage compartment at appropriate temperature without being influenced by an external environment of the storage compartment. According to an embodiment of the disclosure, the insulation may include a foaming insulation. The foaming insulation may be molded by fixing the inner case and the outer case with jigs, etc. and then injecting and foaming urethane foam as a mixture of polyurethane and a foaming agent between the inner case and the outer case.

[0048] According to an embodiment of the disclosure, the insulation may include a vacuum insulation in addition to a foaming insulation, or may be configured only with a vacuum insulation instead of a forming insulation. The vacuum insulation may include a core material and a cladding material accommodating the core material and sealing the inside with vacuum or pressure close to vacuum. However, the insulation is not limited to the above-mentioned foaming insulation or vacuum insulation, and may include various materials capable of being used for insulation.

[0049] The “storage compartment” may include a space defined by the inner case. The storage compartment may further include the inner case defining the space corresponding to the storage compartment. The storage compartment may store a variety of items, such as food, medicines, cosmetics, and the like, and the storage compartment may be configured to be open on at least one side for insertion and removal of the items.

[0050] The refrigerator may include one or more storage compartments. In a case in which two or more storage compartments are formed in the refrigerator, the respective storage compartments may have different purposes of use, and may be maintained at different temperatures. To this end, the respective storage compartments may be partitioned by a partition wall including an insulation.

[0051] The storage compartment may be maintained within an appropriate temperature range according to a purpose of use, and may include a “refrigerating compartment”, a “freezing compartment”, and a “temperature conversion compartment” according to purposes of use and / or temperature ranges. The refrigerating compartment may be maintained at an appropriate temperature to keep food refrigerating, and the freezing compartment may be maintained at an appropriate temperature to keep food frozen. The “refrigerating” may be keeping food cold without freezing the food, and for example, the refrigerating compartment may be maintained within a range of 0 degrees Celsius to 7 degrees Celsius. The “freezing” may be freezing food or keeping food frozen, and for example, the freezing compartment may be maintained within a range of −20 degrees Celsius to −1 degrees Celsius. The temperature conversion compartment may be used as either a refrigerating compartment or a freezing compartment according to or regardless of a user's selection.

[0052] The storage compartment may also be referred to by various terms, such as “vegetable compartment”, “freshness compartment”, “cooling compartment”, and “ice-making compartment”, in addition to “refrigerating compartment”, “freezing compartment”, and “temperature conversion compartment”, and the terms, such as “refrigerating compartment”, “freezing compartment”, “temperature conversion compartment”, etc., as used below are to be understood as representing storage compartments having the corresponding purposes of use and the corresponding temperature ranges.

[0053] The refrigerator according to an embodiment of the disclosure may include at least one door configured to open or close the open side of the storage compartment. The respective doors may be provided to open and close one or more storage compartments, or a single door may be provided to open and close a plurality of storage compartments. The door may be rotatably or slidably mounted to the front of the main body.

[0054] The “door” may seal the storage compartment in a closed state. The door, like the main body, may include an insulation to insulate the storage compartment in a closed state.

[0055] According to an embodiment, the door may include an outer door plate forming the front surface of the door, an inner door plate forming the rear surface of the door and facing the storage compartment, an upper cap, a lower cap, and a door insulation provided therein.

[0056] A gasket may be provided on the edge of the inner door plate to seal the storage compartment by coming into close contact with the front surface of the main body when the door is closed. The inner door plate may include a dyke that protrudes rearward to allow a door basket for storing items to be fitted.

[0057] According to an embodiment, the door may include a door body and a front panel that is detachably coupled to the front of the door body and forming the front surface of the door. The door body may include an outer door plate forming the front surface of the door body, an inner door plate forming the rear surface of the door body and facing the storage compartment, an upper cap, a lower cap, and a door insulator provided therein.

[0058] The refrigerator may be classified as French Door Type, Side-by-side Type, Bottom Mounted Freezer (BMF), Top Mounted Freezer (TMF), or Single Door Refrigerator according to the arrangement of the doors and the storage compartments.

[0059] The refrigerator according to an embodiment of the disclosure may include a cold air supply device for supplying cold air to the storage compartment.

[0060] The “cold air supply device” may include a machine, an apparatus, an electronic device, and / or a combination system thereof, capable of generating cold air and guiding the cold air to cool the storage compartment.

[0061] According to an embodiment of the disclosure, the cold air supply device may generate cold air through a cooling cycle including compression, condensation, expansion, and evaporation processes of refrigerants. To this end, the cold air supply device may include a refrigeration cycle device having a compressor, a condenser, an expander, and an evaporator to drive the refrigeration cycle. According to an embodiment of the disclosure, the cold air supply device may include a semiconductor, such as a thermoelectric element. The thermoelectric element may cool the storage compartment by heating and cooling actions through the Peltier effect.

[0062] The refrigerator according to an embodiment of the disclosure may include a machine compartment in which at least some components belonging to the cold air supply device are installed.

[0063] The “machine compartment” may be partitioned and insulated from the storage compartment to prevent heat generated by the components installed in the machine compartment from being transferred to the storage compartment. To dissipate heat from the components installed in the machine compartment, the machine compartment may communicate with outside of the main body.

[0064] The refrigerator according to an embodiment of the disclosure may include a dispenser provided on the door to provide water and / or ice. The dispenser may be provided on the door to allow access by the user without opening the door.

[0065] The refrigerator according to an embodiment of the disclosure may include an ice-making device that produces ice. The ice-making device may include an ice-making tray that stores water, an ice-moving device that separates ice from the ice-making tray, and an ice-bucket that stores ice produced in the ice-making tray.

[0066] The refrigerator according to an embodiment of the disclosure may include a controller for controlling the refrigerator.

[0067] The “controller” may include a memory for storing and / or recording data and / or programs for controlling the refrigerator, and a processor for outputting control signals for controlling the cold air supply device, etc. in accordance with the programs and / or data stored in the memory.

[0068] The memory may store or record various information, data, instructions, programs, and the like necessary for operation of the refrigerator. The memory may store temporary data generated while generating control signals for controlling components included in the refrigerator. The memory may include at least one of a volatile memory or a non-volatile memory, or a combination thereof.

[0069] The processor may control the overall operation of the refrigerator. The processor may control the components of the refrigerator by executing programs stored in memory. The processor may include a separate neural processing unit (NPU) that performs an artificial intelligence (AI) model operation. In addition, the processor may include a central processing unit (CPU), a graphics processor (GPU), and the like. The processor may generate a control signal to control the operation of the cold air supply device. For example, the processor may receive temperature information of the storage compartment from a temperature sensor and generate a cooling control signal to control an operation of the cold air supply device based on the temperature information of the storage compartment.

[0070] Furthermore, the processor may process a user input of a user interface and control an operation of the user interface in accordance with the programs and / or data memorized / stored in the memory. The user interface may be provided with an input interface and an output interface. The processor may receive the user input from the user interface. In addition, the processor may transmit a display control signal and image data for displaying an image on the user interface to the user interface in response to (e.g., based on) the user input.

[0071] The processor and memory may be provided integrally or may be provided separately. The processor may include one or more processors. For example, the processor may include a main processor and at least one sub-processor. The memory may include one or more memories.

[0072] The refrigerator according to an embodiment of the disclosure may include a processor and a memory for controlling all of the components included in the refrigerator, and may include a plurality of processors and a plurality of memories for individually controlling the components of the refrigerator. For example, the refrigerator may include a processor and a memory for controlling the operation of the cold air supply device in accordance with to an output of the temperature sensor. In addition, the refrigerator may be separately provided with a processor and a memory for controlling the operation of the user interface in accordance with the user input.

[0073] A communication module may communicate with external devices, such as servers, mobile devices, and other home appliances via a nearby access point (AP). The AP may connect a local area network (LAN) to which a refrigerator or a user device is connected to a wide area network (WAN) to which a server is connected. The refrigerator or the user device may be connected to the server via the WAN.

[0074] The input interface may include keys, a touch screen, a microphone, and the like. The input interface may receive the user input and pass the received user input to the processor.

[0075] The output interface may include a display, a speaker, and the like. The output interface may output various notifications, messages, information, and the like generated by the processor.

[0076] Hereinafter, various embodiments according to the disclosure will be described in detail with reference to the accompanying drawings.

[0077] FIG. 1 is an external view of a refrigerator according to an embodiment of the disclosure. FIG. 2 is a cross-sectional view of a refrigerator according to an embodiment of the disclosure.

[0078] Referring to FIG. 1 and FIG. 2, a refrigerator 1 may include a main body 10, storage compartments 20 and 30 formed inside the main body 10, and a cooling device 40 for supplying cold air to the storage compartments 20 and 30.

[0079] The main body 10 may include an inner case 10b that defines the storage compartments 20 and 30, an outer case 10a coupled to an outer side of the inner case 10b to form an exterior of the refrigerator 1, and an insulation 10c arranged between the inner case 10b and the outer case 10a to insulate the storage compartments 20 and 30.

[0080] The storage compartments 20 and 30 may be divided by a middle wall 11 into the upper first storage compartment 20 and the lower second storage compartment 30. The first storage compartment 20 may be maintained at a temperature of approximately 3º° C. to store food refrigerated, and the second storage compartment 30 may be maintained at a temperature of approximately minus 19° C. to store food frozen. The first storage compartment 20 may be provided with shelves on which food may be placed and at least one storage box 24 in which food may be stored.

[0081] The first storage compartment 20 and the second storage compartment 30 each have an open front to put in and take out food, and the open front of the first storage compartment 20 may be opened or closed by a pair of doors (21; 21a, 21b) hinged to the main body 10.

[0082] The open front of the second storage compartment 30 may be opened or closed by at least one door 31 hinged to the main body 10.

[0083] According to various embodiments, the number and type of storage compartments, and the number and type of doors for opening and closing each storage compartment may be changed within a scope of general technology.

[0084] According to various embodiments, the first storage compartment 20 and / or the second storage compartment 30 may include a temperature conversion compartment whose temperature may be changed by a user's setting.

[0085] The cooling device 40 may include an evaporator 41 where liquid refrigerant evaporates, a compressor 42 that compresses gaseous refrigerant, a condenser 43 where gaseous refrigerant condenses, and an expander that expands liquid refrigerant.

[0086] The compressor 42 and the condenser 43 may be installed in a machine compartment provided at a rear lower side of the main body 10.

[0087] The evaporator 41 may be installed in a cooling duct 50 provided at an inner rear side of the storage compartments 20 and 30.

[0088] The cooling duct 50 is provided at the inner rear side of the storage compartments 20 and 30 to allow air to flow. The cooling duct 50 may be provided with a fan 51 for discharging air from which heat has been removed by the evaporator 41 (hereinafter referred to as cold air) into the storage compartments 20 and 30 and drawing air from the storage compartments 20 and 30 into the cooling duct 50.

[0089] An outlet 52 may be formed on an upper side of the cooling duct 50 to allow cold air generated by the evaporator 41 to be discharged to the storage compartments 20 and 30. The outlet 52 may be formed as a plurality of holes.

[0090] An inlet 53 may be formed on a lower side of the cooling duct 50 to allow air from the storage compartments 20 and 30 to be introduced into the cooling duct 50. The inlet 53 may be formed as a plurality of holes.

[0091] Although it has been described that the evaporator 41 is disposed at the rear of the storage compartments 20 and 30 and cold air moves from a lower side to an upper side, the position of the evaporator 41 is not limited thereto. For example, the evaporator 41 may be arranged on a lower surface or an upper surface of the storage compartments 20 and 30 to form a corresponding flow path.

[0092] According to various embodiments, the evaporator 41 may be provided to correspond to each of the storage compartments 20 and 30. For example, the evaporator 41 may include a first evaporator corresponding to the first storage compartment 20 and a second evaporator corresponding to the second storage compartment 30.

[0093] According to various embodiments, a temperature sensor 110 for measuring the temperature of the storage compartments 20 and 30 may be provided in the storage compartments 20 and 30.

[0094] In an embodiment, the temperature sensor 110 may include a temperature sensor 110a for measuring a temperature of the first storage compartment 20 and a temperature sensor 110b for measuring a temperature of the second storage compartment 30.

[0095] The temperature sensor 110 may be disposed inside the storage compartments 20 and 30. For example, the temperature sensor 110 may be disposed near the outlet 52 inside the second storage compartment 30, but the position of the temperature sensor 110 is not limited thereto.

[0096] According to various embodiments, a temperature sensor 120 for measuring a temperature of the evaporator 41 may be provided around the evaporator 41. The temperature sensor 120 for measuring the temperature of the evaporator 41 may be disposed on an upper side of the evaporator 41, but the position of the temperature sensor 120 is not limited thereto.

[0097] According to various embodiments, the temperature sensor 120 may be disposed in a middle region of the evaporator 41.

[0098] According to one or more embodiments, a plurality of temperature sensors 120 may be provided.

[0099] In a case where water vapor flows in near the evaporator 41, frost may form on the evaporator 41.

[0100] In a case where frost forms on the evaporator 41, heat exchange between the air around the evaporator 41 and the refrigerant flowing through the evaporator 41 is hindered, and thus heat exchange efficiency decreases.

[0101] In an embodiment, the refrigerator 1 may include a defrost heater 70 for removing frost formed on the evaporator 41.

[0102] The defrost heater 70 may be provided around the evaporator 41. For example, the defrost heater 70 may be disposed on a lower side of the evaporator, but the position of the defrost heater 70 is not limited thereto.

[0103] The defrost heater 70 may remove ice or frost generated on the evaporator 41 and an outlet of the cooling duct 50, and the like, to allow cold air to be smoothly discharged to the storage compartments 20 and 30.

[0104] The defrost heater 70 may include at least one of a sheath heater, a cord heater, high-temperature gas of the cycle itself, or a heat pump cycle.

[0105] Air heated by the defrost heater 70 rises and moves by convection. Frost formed on the evaporator 41 may be removed by the air heated by the defrost heater 70.

[0106] In an embodiment, during a defrost operation, frost formed on the evaporator 41 may be removed by operating the defrost heater 70.

[0107] In an embodiment, during the defrost operation, the operation of the compressor 42 may be stopped, and thus compressed refrigerant may not be supplied to the evaporator 41.

[0108] In an embodiment, during the defrost operation, the operation of the fan 51 may be stopped to prevent air heated by the defrost heater 70 from being introduced into the storage compartments 20 and 30 through the outlet 52.

[0109] FIG. 3 and FIG. 4 are diagrams for illustrating a cooling device of a refrigerator according to an embodiment of the disclosure.

[0110] In an embodiment, the cooling device 40 may include the evaporator 41 generating cold air through heat exchange, a refrigerant pipe 41a for transferring gaseous refrigerant evaporated in the evaporator 41 to the compressor 42, the compressor 42 compressing the gaseous refrigerant provided through the refrigerant pipe 41a, a refrigerant pipe 42a for transferring the gaseous refrigerant compressed by the compressor 42 to the condenser, and the condenser 43 condensing the refrigerant provided through the refrigerant pipe 42a.

[0111] A motor of the compressor 42 receives a drive current under control of a controller 100, which will be described below, and rotates a rotating shaft through magnetic interaction between a rotor and a stator. A rotational force generated by the motor is converted into a linear motion force by a piston in the compressor 42, and the gaseous refrigerant may be compressed to a high pressure through the linear motion force of the piston. In addition, the rotational force generated by the motor of the compressor 42 may be transmitted to a rotating blade connected to the rotating shaft of the motor, allowing the gaseous refrigerant to be compressed to a high pressure using a stick-slip phenomenon between the rotating blade and a container of the compressor 42.

[0112] The motor of the compressor 42 may include an induction AC servo motor, a synchronous AC servo motor, a brushless direct current (BLDC) motor, or the like.

[0113] Through the pressure by the compressor 42, the refrigerant may circulate through the condenser 43, an expansion valve 45, and the evaporator 41. That is, the compressor 42 performs a vital role in the cooling device 40 that cools the storage compartments 20 and 30. Driving the cooling device 40 may be considered driving the compressor 42.

[0114] According to one or more embodiments, the cooling device 40 may include the condenser 43 for condensing the refrigerant compressed by the compressor 42. When the condenser 43 condenses the refrigerant, the temperature of the condenser 43 may increase due to latent heat released by the refrigerant. In an embodiment, the cooling device 40 may include a heat dissipation fan for cooling the condenser 43.

[0115] According to one or more embodiments, the cooling device 40 may include the expansion valve 45 for expanding the refrigerant condensed in the condenser 43. The expansion valve 45 may reduce the pressure of the high-pressure liquid refrigerant to a pressure that may cause evaporation by a throttling process. The throttling process refers to a reduction in pressure without heat exchange with the outside air when a fluid passes through a narrow flow path such as a nozzle or an orifice.

[0116] The expansion valve 45 may adjust the amount of refrigerant supplied to the evaporator 41 to allow the refrigerant to absorb sufficient heat in the evaporator 41. In addition, the opening and closing and / or an opening degree of the expansion valve 45 may be adjusted by the controller 100, which will be described below.

[0117] The opening and closing of the expansion valve 45 may be controllable.

[0118] For example, the expansion valve 45 may include a thermoelectric electronic expansion valve that uses deformation of a bimetal, a thermostatic electronic expansion valve that uses volumetric expansion by heating enclosed wax, a pulse width modulation type electronic expansion valve for opening or closing a solenoid valve by a pulse signal, or a step motor type electronic expansion valve that uses a motor to open or close the valve.

[0119] The refrigerant that has passed through the expansion valve 45 may be transferred to a capillary tube 43b through a refrigerant pipe 43a and expanded. The capillary tube 43b may be implemented by a thin tube, and may expand high-temperature, high-pressure liquid refrigerant and discharge low-temperature, low-pressure refrigerant mixed with gas and liquid to a refrigerant pipe 43c connected to the evaporator 41.

[0120] According to one or more embodiments, the capillary tube 43b may be omitted.

[0121] Surrounding air may be cooled by the evaporator 41, and the fan 51 may introduce the surrounding air cooled by the evaporator 41 into the storage compartments 20 and 30.

[0122] The low-pressure gaseous refrigerant evaporated by the evaporator 41 may be provided to the compressor 42 again, and the cooling cycle may be repeated. That is, the refrigerant may circulate by sequentially passing through the compressor 42, the condenser 43, and the evaporator 41, thereby cooling the storage compartments 20 and 30.

[0123] Inside the storage compartments 20 and 30, the temperature sensor 110 (hereinafter referred to as ‘inside temperature sensor 110’) for measuring the temperature of the storage compartments 20 and 30 may be provided.

[0124] In the cooling duct 50 where the evaporator 41 is installed, the temperature sensor 120 (hereinafter referred to as ‘evaporator temperature sensor 120’) for measuring the temperature of the evaporator 41 may be provided.

[0125] The evaporator temperature sensor 120 may be disposed near the evaporator 41.

[0126] The defrost heater 70 may be located on one side (e.g., a lower part) of the evaporator 41.

[0127] According to one or more embodiments, in a case where the refrigerator 1 includes an ice maker, the cooling device 40 may include a switching valve for transferring refrigerant condensed by the condenser 43 to the evaporator 41 on the icemaker side.

[0128] FIG. 5 is an example of a control block diagram of a refrigerator according to an embodiment of the disclosure.

[0129] Referring to FIG. 5, the refrigerator 1 may include a plurality of controllable electrical components (e.g., the compressor 42, the fan 51, the expansion valve 45, and / or the defrost heater 70), the controller 100 for controlling the plurality of electrical components of the refrigerator (e.g., the compressor 42, the fan 51, the expansion valve 45, and / or the defrost heater 70), the inside temperature sensor 110 for measuring a temperature of the storage compartments 20 and 30, and the evaporator temperature sensor 120 for measuring a temperature of the evaporator 41.

[0130] The controller 100 may include at least one memory storing a program for performing the above-described operations or operations to be described below and various data required to execute the program, and at least one processor that executes the stored program.

[0131] The controller 100 may include hardware such as a central processing unit (CPU), a Micom (e.g., main control unit (MCU), microprocessor unit (MPU)), the at least one memory 102 and the at least one processor 101, and software such as a control program. For example, the controller 100 may include the at least one memory 102 that stores information, algorithms, and / or data in the form of program for controlling the operation of components in the refrigerator, and the at least one processor 101 that performs the above-described operations and operations to be described below using the data and / or information stored in the at least one memory 102. The memory 102 and the processor 101 may each be implemented as separate chips. The processor 101 may include one or more processor chips or one or more processing cores. The memory 102 may include one or more memory chips or one or more memory blocks. In addition, the memory 102 and the processor 101 may be implemented as a single chip or as a plurality of chips.

[0132] The memory 102 may include a volatile memory such as a static random access memory (S-RAM) or a dynamic random access memory (D-RAM), and a non-volatile memory such as a read only memory (ROM), an erasable programmable read only memory (EPROM), or an electrically erasable programmable read only memory (EEPROM).

[0133] A person skilled in the art will readily understand that controlling the compressor 42 in the disclosure may include controlling the motor of the compressor 42, and controlling the fan 51 may include controlling the motor of the fan 51.

[0134] The controller 100 may control the compressor 42 by controlling a driving circuit for driving the compressor 42. The controller 100 may obtain operation information of the compressor 42 from the driving circuit for driving the compressor 42.

[0135] The operation information of the compressor 42 may include information about an operating frequency of the compressor 42 and / or an operation time of the compressor 42.

[0136] The controller 100 may control the fan 51 by controlling a driving circuit for driving the fan 51. The controller 100 may obtain operation information of the fan 51 from the driving circuit for driving the fan 51.

[0137] The operation information of the fan 51 may include information about an operating revolutions per minute (RPM) of the fan 51 and / or an operation time of the fan 51.

[0138] The controller 100 may receive temperature information of the storage compartments 20 and 30 from the inside temperature sensor 110.

[0139] The temperature information of the storage compartments 20 and 30 may include data about temperature value of the storage compartments 20 and 30 measured by the inside temperature sensor 110.

[0140] The controller 100 may receive temperature information of the evaporator 41 from the evaporator temperature sensor 120.

[0141] The temperature information of the evaporator 41 may include data about a temperature value of the evaporator 41 measured by the evaporator temperature sensor 120.

[0142] In an embodiment, the controller 100 may control the compressor 42 and / or the fan 51 based on the temperature of the storage compartments 20 and 30.

[0143] For example, the controller 100 may operate the compressor 42 and the fan 51 in response to the temperature of the storage compartments 20 and 30 being lower than a preset target temperature.

[0144] A cooling operation may be defined as an operation in which the controller 100 operates the compressor 42 and the fan 51.

[0145] As another example, the controller 100 may adjust an opening degree of the expansion valve 45 in response to a temperature change rate of the storage compartments 20 and 30 being lower than a preset target temperature change rate.

[0146] According to one or more embodiments, the controller 100 may operate the defrost heater 70 based on a determination that the evaporator 41 requires defrosting.

[0147] According to one or more embodiments, the controller 100 may stop the operation of the compressor 42 and the fan 51 while the defrost heater 70 is in operation.

[0148] A defrost operation may be defined as an operation in which the controller 100 operates the defrost heater 70.

[0149] For example, the controller 100 may operate the defrost heater 70 for a predetermined time (e.g., 10 minutes) at preset defrost cycles (e.g., 10 hours).

[0150] In an embodiment, the refrigerator 1 may include a door opening / closing sensor for detecting opening and closing of the doors 21 and 31, and the controller 100 may advance the preset defrost cycle based on an opening count and an opening time of the doors 21 and 31.

[0151] Meanwhile, unless the refrigerator 1 is equipped with an expensive sensor capable of accurately detecting the amount of frost formed on the evaporator 41, the amount of frost formed on the evaporator 41 is to be estimated based on factors (e.g., the opening count and opening time of the doors 21 and 31) that may estimate the amount of frost formed on the evaporator 41.

[0152] According to the disclosure, a method that may relatively accurately estimate the amount of frost formed on the evaporator 41 using factors that estimate the amount of frost formed on the evaporator 41 may be provided.

[0153] A relatively accurate estimation of the amount of frost formed on the evaporator 41 may operate the defrost heater 70 economically, thereby increasing energy efficiency.

[0154] In addition, a relatively accurate estimation of the amount of frost formed on the evaporator 41 may allow for an immediate removal of the frost formed on the evaporator 41 when required, thereby increasing the energy efficiency of the cooling device 40.

[0155] Hereinafter, an embodiment of the disclosure is described that may determine (e.g., identify) an optimal operation time of the defrost heater 70 based on alternative factors that may estimate the amount of frost formed on the evaporator 41.

[0156] FIG. 6 is a flowchart illustrating an example of a method for controlling a refrigerator according to an embodiment of the disclosure.

[0157] Referring to FIG. 6, the controller 100 may record predetermined information at defined time intervals (e.g., 10-minute intervals) (1000).

[0158] In an embodiment, the memory 102 may record predetermined information at defined time intervals (e.g., 10-minute intervals).

[0159] Recording predetermined information at defined time intervals may include storing the predetermined information in the memory 102 at defined time intervals.

[0160] Recording predetermined information at defined time intervals may include separately storing, in the memory 102, the predetermined information stored at defined time intervals among information continuously stored in the memory 102.

[0161] According to one or more embodiments, the memory 102 may include a volatile memory and a non-volatile memory.

[0162] Storing predetermined information in the memory 102 at defined time intervals may include storing the predetermined information in a non-volatile memory at defined time intervals.

[0163] Separately storing, in the memory 102, predetermined information stored at defined time intervals among information continuously stored in the memory 102 may include storing, in the non-volatile memory, predetermined information stored at defined time intervals among predetermined information stored in the volatile memory.

[0164] The predetermined information stored in the non-volatile memory at defined time intervals may be copied to the volatile memory when the refrigerator 1 is turned on.

[0165] Separately storing, in the memory 102, predetermined information stored at defined time intervals among information continuously stored in the memory 102 may include separately storing, in the non-volatile memory, predetermined information stored at defined time intervals among predetermined information stored in the non-volatile memory.

[0166] The processor 101 may read the predetermined information recorded in the memory 102 at defined time intervals, and may perform various operations to be described below based on the information.

[0167] Accordingly, recording predetermined information at defined time intervals may include the memory 102 storing predetermined information to be used later by the processor 101.

[0168] In an embodiment, the controller 100 may record temperature information of the storage compartments 20 and 30, temperature information of the evaporator 41, operation information of the compressor 42, and operation information of the fan 51 at defined time intervals.

[0169] The temperature information of the storage compartments 20 and 30 may be obtained from the inside temperature sensor 110, and may include the temperature of the storage compartments 20 and 30.

[0170] The temperature information of the evaporator 41 may be obtained from the evaporator temperature sensor 120, and may include the temperature of the evaporator 41.

[0171] The operation information of the compressor 42 may be obtained from a driving circuit that drives the compressor 42, and may include an operation time and / or operating frequency of the compressor 42.

[0172] The operation information of the fan 51 may be obtained from a driving circuit that drives the fan 51, and may include an operation time and / or operating RPM of the fan 51.

[0173] According to one or more embodiments, the controller 100 may record operation information of the expansion valve 45 at defined time intervals.

[0174] The operation information of the expansion valve 45 may include an open / closed state of the expansion valve 45.

[0175] In an embodiment, the controller 100 may record predetermined information in the memory 102 at defined time intervals.

[0176] According to one or more embodiments, the memory 102 may store up to n pieces of information (where n is a natural number greater than or equal to 2). For example, the memory 102 may store up to 40 pieces of information.

[0177] Assuming the defined time interval is 10 minutes, the memory 102 may record predetermined information for 400 minutes.

[0178] According to one or more embodiments, in a case where the number of pieces of information recorded at defined time intervals exceeds a predetermined number (e.g., 40 pieces), the controller 100 may delete the oldest recorded information.

[0179] According to the disclosure, as the oldest recorded information is deleted, the reliability of the recorded information may be increased.

[0180] The controller 100 may omit the calculation of an index value, in response to an index value calculation condition not being satisfied (No in operation 1100).

[0181] The index value is a value that may be used to detect a defrost condition. In the disclosure, the index value may be used as one factor for determining whether the defrost condition is satisfied.

[0182] The index value calculation condition may include various conditions under which frost formation on the evaporator 41 may be reasonably estimated.

[0183] For example, the index value calculation condition may include an elapse of a preset time (e.g., 10 hours) after a defrost operation ends, i.e., after an operation of the defrost heater 70 is stopped.

[0184] As another example, the index value calculation condition may include an elapse of a preset time (e.g., 5 hours) after the refrigerator 1 is turned on.

[0185] The controller 100 may calculate (e.g., identify) the index value at defined time intervals (1200), in response to the index value calculation condition being satisfied (Yes in operation 1100).

[0186] For example, the controller 100 may calculate the index value at defined time intervals, in response to an elapse of a preset time (e.g., 5 hours or 10 hours) from the time point when the operation of the defrost heater 70 ends and / or the time point when power is applied to the refrigerator 1.

[0187] Before the preset time elapses from the time point when power is applied to the refrigerator 1 and / or the time point when the operation of the defrost heater 70 ends, there is realistically insufficient time for frost to form on the evaporator 41.

[0188] According to the disclosure, by starting to calculate the index value from the time point when frost is expected to form on the evaporator 41, the use of an index value with low reliability may be prevented.

[0189] According to one or more embodiments, the controller 100 may calculate the index value at the defined time intervals in response to a first preset time having elapsed from the time point when the refrigerator 1 was turned on. The time point when the refrigerator 1 was turned on refers to the time point when the refrigerator 1 started receiving power from an external power source.

[0190] According to one or more embodiments, the controller 100 may calculate the index value at the defined time intervals in response to a second preset time having elapsed from the time point when the operation of the defrost heater 70 finished.

[0191] In this instance, the first preset time may be shorter than the second preset time.

[0192] Because the time point when the refrigerator 1 was turned on corresponds to an initial installation time point of the refrigerator 1, a large amount of water vapor is highly likely to have flowed in near the evaporator 41.

[0193] According to the disclosure, by setting the first preset time to be shorter than the second preset time, index values with low reliability may be excluded, and whether frost has formed on the evaporator 41 may be estimated at an optimal time.

[0194] The controller 100 may record predetermined information at defined time intervals, and calculate the index value based on the recorded predetermined information.

[0195] According to one or more embodiments, the controller 100 may calculate the index value, based on temperature information of the storage compartments 20 and 30 and temperature information of the evaporator 41 recorded at the most recent time point and temperature information of the storage compartments 20 and 30 and temperature information of the evaporator 41 recorded at a past time point that satisfies a defined condition.

[0196] In a case where frost forms on the evaporator 41, air heat-exchanged by the evaporator 41 may be trapped by the frost, and thus the temperature of the storage compartments 20 and 30 may not decrease, while the temperature of the evaporator41 may decrease.

[0197] That is, in a case where frost forms on the evaporator 41, a difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30 increases.

[0198] Meanwhile, even in a case where frost does not form on the evaporator 41, the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30 may be increased by many other conditions.

[0199] For example, the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30 may change depending on various factors, such as an operating frequency of the compressor 42, an open / closed state of the expansion valve 45, and / or an operating RPM of the fan 51, regardless of the presence or absence of frost formed on the evaporator 41.

[0200] According to the disclosure, by using not only predetermined information recorded at the most recent time point but also predetermined information recorded at a past time point that satisfies a defined condition, whether frost has formed on the evaporator 41 may be robustly estimated based on various factors that may change the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30, in addition to the frost formed on the evaporator 41.

[0201] According to one or more embodiments, the controller 100 may determine whether the defrost condition is satisfied based on the index value (1300).

[0202] The controller 100 may operate the defrost heater 70 (1400), in response to determining that the defrost condition is satisfied (Yes in operation 1300).

[0203] The controller 100 may add a predetermined additional time k2 (e.g., approximately 15 hours) to a preset defrost cycle k1 (1350), in response to determining that the defrost condition is not satisfied (No in operation 1300).

[0204] In a case where a time obtained by adding the predetermined additional time k2 to the preset defrost cycle k1 is defined as a preset time (k1+k2), the controller 100 may operate the defrost heater 70 based on a cumulative operation time of the compressor 42 exceeding the preset time (k1+k2) in response to determining that the defrost condition is not satisfied.

[0205] That is, in a case where the defrost condition is not satisfied based on the index value, the controller 100 may operate the defrost heater 70 in response to the cumulative operation time of the compressor 42 exceeding the preset defrost cycle k1 and the predetermined additional time k2 (1400).

[0206] However, in a case where it is determined that the defrost condition is satisfied before the cumulative operation time of the compressor 42 exceeds the preset time (k1+k2), the controller 100 may immediately operate the defrost heater 70.

[0207] According to the disclosure, the defrost heater 70 may be prevented from unnecessarily operating by adding the predetermined additional time k2 to the preset defrost cycle k1 in a case where the defrost condition is not satisfied. Thus, energy efficiency may be improved.

[0208] The defrost heater 70 may be operated for a preset time, and based on an elapse of the preset time, the operation of the defrost heater 70 may be stopped to complete the defrost operation (1500).

[0209] For example, the defrost heater 70 may operate until the temperature of the evaporator 41 measured by the evaporator temperature sensor 120 reaches a predetermined temperature. As another example, an operation time of the defrost heater 70 may vary depending on the estimated amount of frost, as described below.

[0210] That is, in a case where the estimated amount of frost on the evaporator 41 is large, the operation time of the defrost heater 70 may be lengthened, and in a case where the estimated amount of frost on the evaporator 41 is small, the operation time of the defrost heater 70 may be shortened.

[0211] When the defrost operation is completed, the controller 100 may perform from operation 1100 again.

[0212] An embodiment in which the controller 100 determines whether the defrost condition is satisfied based on the index value will be described below with reference to FIG. 8 to FIG. 10.

[0213] According to one or more embodiments, some of the operations shown in FIG. 6 may be omitted, and some operations may be added. In addition, the order of the operations shown in FIG. 6 may change.

[0214] FIG. 7 is a diagram illustrating an example of a method for controlling a refrigerator over time according to an embodiment of the disclosure.

[0215] Referring to FIG. 7, the controller 100 may record predetermined information at defined time intervals from a time point t1 when the refrigerator 1 is turned on (operation 1000 of FIG. 6).

[0216] The controller 100 may calculate an index value at defined time intervals in response to an index value calculation condition being satisfied.

[0217] For example, the controller 100 may calculate the index value at defined time intervals (operation 1200 of FIG. 6), in response to a first preset time h1 (e.g., approximately 5 hours) having elapsed from the time point t1 when the refrigerator 1 was turned on (Yes in operation 1100 of FIG. 6).

[0218] That is, the controller 100 may calculate the index value at defined time intervals from a time point t2 when the first preset time h1 has elapsed from the time point t1 when the refrigerator 1 was turned on.

[0219] The controller 100 may determine whether the defrost condition is satisfied based on the index value (operation 1300 of FIG. 6).

[0220] The controller 100 may operate the defrost heater 70 (operation 1400 of FIG. 6), in response to determining that the defrost condition is satisfied (Yes in operation 1300 of FIG. 6).

[0221] That is, the controller 100 may operate the defrost heater 70 at a time point t3 when it is determined that the defrost condition is satisfied.

[0222] The controller 100 may operate the defrost heater 70 for a predetermined time, and stop the operation of the defrost heater 70 in response to the elapse of the predetermined time, thereby ending the defrost operation (operation 1500 of FIG. 6).

[0223] The controller 100 may calculate the index value at defined time intervals in response to the index value calculation condition being satisfied.

[0224] For example, the controller 100 may calculate the index value at defined time intervals, in response to a second preset time h2 (e.g., approximately 5 hours) having elapsed from a time point t4 when the operation of the defrost heater 70 was stopped.

[0225] That is, the controller 100 may calculate the index value at defined time intervals from a time point t5 when the second preset time h2 has elapsed from the time point t4 when the operation of the defrost heater 70 was stopped.

[0226] As such, according to the disclosure, operations 1100, 1200, 1300, 1350, 1400, and 1500 of FIG. 6 may be repeatedly performed.

[0227] FIG. 8 illustrates an example of predetermined information recorded by a refrigerator according to an embodiment of the disclosure.

[0228] Referring to FIG. 8, predetermined information recorded at defined time intervals by the refrigerator 1 according to an embodiment may be confirmed.

[0229] Hereinafter, for convenience of description, it is defined that information arranged at a lower side is closer to the present, and information arranged at an upper side is closer to the past.

[0230] According to one or more embodiments, the controller 100 may collect predetermined information at defined time intervals (e.g., 10 minutes).

[0231] In an embodiment, the predetermined information may include temperature information of the storage compartments 20 and 30, temperature information of the evaporator 41, operation information of the compressor 42, and operation information of the fan 51.

[0232] According to one or more embodiments, the predetermined information may further include operation information of the expansion valve 45.

[0233] Assuming that the information arranged in each row constitutes one piece of information, in a case where the number of pieces of information recorded at defined time intervals exceeds a predetermined number (e.g., 40), the controller 100 may delete the oldest recorded information among the information recorded at defined time intervals, and new information may be updated.

[0234] For example, assuming that the predetermined number is 40, the information in the first row may be deleted at each defined time interval, and new information may be added to the last row.

[0235] According to one or more embodiments, the controller 100 may record information only when reliability is ensured. For example, the controller 100 may record the temperature information of the evaporator 41 and the temperature information of the storage compartments 20 and 30 only when a temperature of the evaporator 41 and / or a temperature of the storage compartments 20 and 30 fluctuates within a predetermined range for a predetermined time (e.g., approximately 1 minute). As another example, the controller 100 may record the operation information of the compressor 42 only when an operating frequency of the compressor 42 fluctuates within a predetermined range for a predetermined time (e.g., approximately 1 minute). As still another example, the controller 100 may record the operation information of the fan 51 only when an operating RPM of the fan 51 fluctuates within a predetermined range for a predetermined time (e.g., approximately 1 minute). As yet another example, the controller 100 may record the operation information of the expansion valve 45 only when an open / closed state of the expansion valve 45 is maintained for a predetermined time (e.g., approximately 1 minute).

[0236] According to the disclosure, the reliability of information recorded at defined time intervals may be secured.

[0237] In an embodiment, the controller 100 may calculate an index value based on the information recorded at defined time intervals.

[0238] To calculate the index value, the controller 100 may determine a past time point that satisfies a defined condition.

[0239] In an embodiment, the defined condition may include the operation information of the compressor 42 and the operation information of the fan 51 recorded at the past time point being identical to the operation information of the compressor 42 and the operation information of the fan 51 recorded at the most recent time point.

[0240] In this instance, the operation information of the compressor 42 being identical may include the operating frequencies of the compressor 42 being identical.

[0241] The operation information of the fan 51 being identical may include the operating RPMs of the fan 51 being identical.

[0242] According to one or more embodiments, the defined condition may include the operation information of the expansion valve 45 recorded at the past time point being identical to the operation information of the expansion valve 45 recorded at the most recent time point.

[0243] The operation information of the expansion valve 45 being identical may include the open / closed state of the expansion valve 45 being identical.

[0244] For example, in a case where operation information c40 of the compressor 42 and operation information d40 of the fan 51 recorded at the most recent time point P40 are identical to operation information c3 of the compressor 42 and operation information d3 of the fan 51 recorded at a past time point P3, respectively, the controller 100 may determine that the past time point P3 satisfies the defined condition.

[0245] As another example, in a case where the operation information c40 of the compressor 42, the operation information d40 of the fan 51, and operation information e40 of the expansion valve 45 recorded at the most recent time point P40 are identical to operation information c1 of the compressor 42, operation information d1 of the fan 51, and operation information e1 of the expansion valve 45 recorded at a past time point P1, respectively, the controller 100 may determine that the past time point P1 satisfies the defined condition.

[0246] According to one or more embodiments, in a case where a plurality of past time points that satisfy the defined condition exist, the controller 100 may determine the oldest time point among the plurality of past time points that satisfy the defined condition as the past time point that satisfies the defined condition.

[0247] In other words, in a case where there are a plurality of past time points that satisfy the defined condition, the controller 100 may calculate the index value based on the temperature information of the storage compartments 20 and 30 and the temperature information of the evaporator 41 recorded at the oldest time point among the plurality of past time points.

[0248] For example, in a case where the operation information c40 of the compressor 42 and the operation information d40 of the fan 51 recorded at the most recent time point P40 are identical to the operation information c3 of the compressor 42 and the operation information d3 of the fan 51 recorded at the first past time point P3, respectively, and the operation information c40 of the compressor 42 and the operation information d40 of the fan 51 recorded at the most recent time point P40 are identical to the operation information c2 of the compressor 42 and the operation information d2 of the fan 51 recorded at a second past time point P2, respectively, the controller 100 may determine that the second past time point P2, which is older than the first past time point P3, satisfies the defined condition.

[0249] As another example, in a case where the operation information c40 of the compressor 42, the operation information d40 of the fan 51, and the operation information e40 of the expansion valve 45 recorded at the most recent time point P40 are identical to the operation information c3 of the compressor 42, the operation information d3 of the fan 51, and operation information e3 of the expansion valve 45 recorded at the first past time point P3, respectively, and the operation information c40 of the compressor 42, the operation information d40 of the fan 51, and the operation information e40 of the expansion valve 45 recorded at the most recent time point P40 are identical to the operation information c2 of the compressor 42, the operation information d2 of the fan 51, and operation information e2 of the expansion valve 45 recorded at the second past time point P2, respectively, the controller 100 may determine that the second past time point P2, which is older than the first past time point P3, satisfies the defined condition.

[0250] The controller 100 may calculate the index value based on the temperature information of the storage compartments 20 and 30 and the temperature information of the evaporator 41 recorded at the past time point that satisfies the defined condition, and the temperature information of the storage compartments 20 and 30 and the temperature information of the evaporator 41 recorded at the most recent time point.

[0251] The index value may be calculated by [Equation 1] below.index=L1(a-b)-L2(c-d)[Equation⁢ 1]

[0252] Here, index denotes the index value, L1 denotes a defined first weight, L2 denotes a defined second weight, a denotes a temperature value of the evaporator 41 recorded at the most recent time point, b denotes a temperature value of the storage compartments 20 and 30 recorded at the most recent time point, c denotes a temperature value of the evaporator 41 recorded at a past time point that satisfies the defined condition, and d denotes a temperature value of the storage compartments 20 and 30 recorded at a past time point that satisfies the defined condition.

[0253] In an embodiment, the controller 100 may determine a first value L1 (a−b) by assigning the defined first weight L1 to a difference value (a−b) between the temperature value a of the evaporator 41 and the temperature value b of the storage compartments 20 and 30 recorded at the most recent time point, and may determine a second value L2(c−d) by assigning the defined second weight L2 to a difference value (c−d) between the temperature value c of the evaporator 41 and the temperature value d of the storage compartments 20 and 30 recorded at a past time point that satisfies the defined condition. In addition, the controller 100 may determine the index value based on a difference value (L1(a−b)−L2(c−d)) between the first value and the second value.

[0254] The first weight L1 and the second weight L2 may be set according to characteristics of the refrigerator 1. According to one or more embodiments, optimal values for the first weight L1 and the second weight L2 may be set through machine learning. For example, the first weight L1 and the second weight L2 may be set to 0.5 and 0.3, respectively, but are not limited thereto.

[0255] In an embodiment, the first weight L1 may be greater than the second weight L2.

[0256] In a case where the first weight L1 is greater than the second weight L2, a temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the most recent time point and a temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the past time point may be considered.

[0257] For example, [Equation 1] may be reproduced as [Equation 2] below.index=(L1-L2)⁢(a-b)+L2((a-b-(c-d))[Equation⁢ 2]

[0258] In a case where the first weight L1 is greater than the second weight L2, the temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the most recent time point may be considered, and at the same time, ‘the temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the most recent time point and the temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the past time point’ may also be considered to calculate the index value.

[0259] According to the disclosure, the index value may be calculated using not only information at the current time point but also information at a past time point having the same condition, thereby robustly estimating whether frost has formed on the evaporator 41 based on various factors that may change the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30, in addition to the frost formed on the evaporator 41.

[0260] For example, assuming that a past time point that satisfies the defined condition for the most recent time point P40 is the time point P1, an index value f2 corresponding to the most recent time point P40 may be calculated by [Equation 3] below.f2=L1(a4⁢0-b4⁢0)-L2(a1-b1)[Equation⁢ 3]

[0261] As another example, it is assumed that a past time point that satisfies the defined condition for a specific time point P39 is the time point P2.

[0262] In other words, it is assumed that operation information c39 of the compressor 42, operation information d39 of the fan 51, and operation information e39 of the expansion valve 45 recorded at the specific time point P39 are identical to the operation information c2 of the compressor 42, the operation information d2 of the fan 51, and the operation information e2 of the expansion valve 45 recorded at the specific past time point P2, respectively.

[0263] Assuming that a past time point that satisfies the defined condition for the specific time point P39 is the time point P2, an index value f1 corresponding to the specific time point P39 may be calculated by [Equation 4] below.f1=L1(a3⁢9-b3⁢9)-L2(a2-b2)[Equation⁢ 4]

[0264] According to an embodiment, the index value for detecting the defrost condition may be calculated at defined time intervals at which predetermined information is recorded.

[0265] Because recording information and calculating the index value may be performed at defined time intervals once the index value calculation condition is satisfied, information about the index value corresponding to each information recording time point P39 and P40 may also be recorded together as information corresponding to each recording time point P39 and P40.

[0266] In general, when the refrigerator 1 is in operation, a past time point that satisfies the defined condition exists. However, in a case where no past time point that satisfies the defined condition exists, an error may occur during the index value calculation.

[0267] In an embodiment, in a case where no past time point satisfies the defined condition, the controller 100 may omit the calculation of the index value corresponding to the most recent time point.

[0268] According to the disclosure, an error that may occur while calculating the index value in a case where no past time point that satisfies the defined condition exists may be prevented.

[0269] As described above, the controller 100 may determine whether the defrost condition is satisfied based on the index value.

[0270] In an embodiment, the controller 100 may accurately identify an operation time point of the defrost heater 70 by considering other alternative factors together with the index value.

[0271] In an embodiment, the controller 100 may determine whether the defrost condition is satisfied based on the index value, the operation information of the compressor 42, and the operation information of the fan 51.

[0272] For example, as an alternative factor for estimating the amount of frost formed on the evaporator 41, a continuous operation time of the compressor 42 may be used. In a case where frost forms on the evaporator 41, the temperature of the storage compartments 20 and 30 may not reach a target temperature, and thus the compressor 42 may operate continuously.

[0273] The controller 100 may count an operation time of the compressor 42, and determine that part of the defrost condition is satisfied in response to the compressor 42 operating continuously for a preset time (e.g., approximately 2 hours).

[0274] As an alternative factor for estimating the amount of frost formed on the evaporator 41, a change in the rotation speed of the fan 51 may be used. In a case where frost forms on the evaporator 41, a flow rate in the storage compartments 20 and 30 may decrease, and thus the rotation speed of the fan 51 may fluctuate.

[0275] For example, in a case where frost forms on the evaporator 41 and the flow rate in the storage compartments 20 and 30 decreases, the rotation speed of the fan 51 may increase.

[0276] In an embodiment, the controller 100 may measure the rotation speed of the fan 51 during a first cooling operation after the operation of the defrost heater 70 ends, and may record the measured rotation speed of the fan 51 in the memory 102 as a reference rotation speed.

[0277] The controller 100 may compare the rotation speed of the fan 51 with the reference rotation speed recorded in the memory 102 at defined time intervals, and may determine that part of the defrost condition is satisfied in response to a difference value between the rotation speed of the fan 51 and the reference rotation speed recorded in the memory 102 being greater than a predetermined value. In other words, the controller 100 may determine that part of the defrost condition is satisfied in response to the rotation speed of the fan 51 being greater than a threshold rotation speed. Here, the threshold rotation speed may be a speed obtained by adding a speed corresponding to the predetermined value to the reference rotation speed recorded in the memory 102.

[0278] According to one or more embodiments, the controller 100 may determine whether part of the defrost condition is satisfied based on the index value calculated at defined time intervals.

[0279] According to one or more embodiments, the controller 100 may determine that the defrost condition is satisfied in response to at least one of the defrost conditions being satisfied.

[0280] A plurality of defrost conditions may exist and may be set according to characteristics of the refrigerator 1.

[0281] According to one or more embodiments, the defrost condition may be set to an optimal condition through machine learning.

[0282] Hereinafter, an example of the defrost condition is described with reference to FIG. 9 and FIG. 10. However, the defrost condition may be changed and added according to characteristics of the refrigerator 1.

[0283] FIG. 9 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure. FIG. 10 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure.

[0284] Referring to FIG. 9, a defrost condition according to an embodiment may include continuous operation of the compressor 42 for a preset time (e.g., approximately 2 hours), a rotation speed of the fan 51 being greater than a threshold rotation speed, and an index value corresponding to the most recent time point P40 being greater than a threshold value. In this instance, the preset time and / or the threshold rotation speed and / or the threshold value may be set in advance, and may vary depending on characteristics of the refrigerator 1. For example, the preset time may be set to approximately 1 hour and 30 minutes and the threshold value may be set to approximately 11, but is not limited thereto.

[0285] For example, the preset time and / or the threshold rotation speed and / or the threshold value may be set to an optimal value derived through machine learning.

[0286] In an embodiment, the controller 100 may determine that the defrost conditions are satisfied, based on the compressor 42 operating for the preset time, the rotation speed of the fan 51 being greater than the defined threshold rotation speed, and the index value corresponding to the most recent time point being greater than or equal to the threshold value.

[0287] Referring to FIG. 10, the defrost condition according to an embodiment may include continuous operation of the compressor 42 for a preset time (e.g., approximately 2 hours), and a predetermined number (e.g., 3) of consecutive index values calculated at defined time intervals all being greater than a threshold value.

[0288] The predetermined number of consecutive index values calculated at defined time intervals may include an index value corresponding to the most recent time point P40, and may include at least one index value corresponding to at least one previous time point P39 and P38.

[0289] In this instance, the preset time and / or the predetermined number and / or the threshold value may be set in advance, and may vary depending on characteristics of the refrigerator 1.

[0290] For example, the preset time and / or the predetermined number and / or the threshold value may be set to an optimal value derived through machine learning.

[0291] Assuming the predetermined number is 3, the defrost conditions may be satisfied in a case where the index values calculated at the three most recent consecutive time points P40, P39, and P38 are all greater than the threshold value and the compressor 42 is operating continuously for the preset time (e.g., approximately 2 hours).

[0292] In an embodiment, the controller 100 may determine that the defrost conditions are satisfied in response to the compressor 42 operating continuously for the preset time and the predetermined number of consecutive index values calculated at defined time intervals all being greater than the threshold value.

[0293] However, the defrost condition is not limited to the conditions described above.

[0294] For example, the controller 100 may determine that the defrost condition is satisfied in response to a predetermined number (e.g., 5) of consecutive index values calculated at defined time intervals all being greater than a threshold value.

[0295] According to one or more embodiments, the controller 100 may determine an operation time of the defrost heater 70 based on which of a plurality of defrost conditions is satisfied.

[0296] For example, for convenience of description, it is assumed that a first defrost condition includes continuous operation of the compressor 42 for a preset time and a predetermined number of consecutive index values calculated at defined time intervals all being greater than a threshold value, and a second defrost condition includes continuous operation of the compressor 42 for a preset time, a rotation speed of the fan 51 being greater than a threshold rotation speed, and an index value corresponding to the most recent time point being greater than a threshold value.

[0297] The controller 100 may operate the defrost heater 70 for a first period of time in response to the first defrost condition being satisfied, and may operate the defrost heater 70 for a second period of time longer than the first period of time in response to the second defrost condition being satisfied.

[0298] According to the disclosure, a more reliable result value may be derived by using not only current data but also past data when calculating the index value.

[0299] According to the disclosure, whether frost has formed on the evaporator 41 may be accurately estimated by considering various results that may occur when frost has formed on the evaporator 41.

[0300] According to the disclosure, energy efficiency may be increased by preventing the defrost heater 70 from operating when a defrost operation is not required.

[0301] According to an embodiment of the disclosure, a refrigerator may include; a storage compartment; an evaporator; a defrost heater provided around the evaporator; a compressor configured to compress a refrigerant discharged from the evaporator; a fan configured to supply air cooled by the evaporator to the storage compartment; memory configured to record temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and at least one processor configured to operate the defrost heater in response to determining that a defrost condition is satisfied.

[0302] The at least one processor may be configured to calculate an index value for detecting a defrost condition based on temperature information of the storage compartment and temperature information of the evaporator recorded at a first time point and temperature information of the storage compartment and temperature information of the evaporator recorded at a second time point.

[0303] The at least one processor may be configured to determine whether the defrost condition is satisfied based on the index value.

[0304] The at least one processor may be configured to determine whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan.

[0305] The at least one processor may be configured to operate the defrost heater in response to determining that the defrost condition is satisfied.

[0306] The at least one processor may be configured to determine a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point.

[0307] The at least one processor may be configured to determine a second value by assigning a defined second weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the second time point.

[0308] The at least one processor may be configured to determine the index value based on a difference value between the first value and the second value.

[0309] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0310] The at least one processor may be configured to determine an oldest time point among the plurality of past time points as the second time point, based on presence of a plurality of past time points that satisfy the defined condition.

[0311] The at least one processor may be configured to omit calculation of an index value corresponding to the first time point, based on absence of a past time point that satisfies the defined condition.

[0312] The at least one processor may be configured to delete oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

[0313] The at least one processor may be configured to calculate the index value at the defined time intervals, in response to an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

[0314] The at least one processor may be configured to determine that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

[0315] The at least one processor may be configured to determine that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, and a defined number of consecutive index values calculated at the defined time intervals all being greater than a threshold value.

[0316] The at least one processor may be configured to operate the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, in response to determining that the defrost condition is not satisfied.

[0317] According to an embodiment of the disclosure, in a method for controlling a refrigerator including a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator; and a fan configured to supply air cooled by the evaporator to the storage compartment, the method may include: recording temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and calculating an index value for detecting a defrost condition based on temperature information of the storage compartment and temperature information of the evaporator recorded at a first time point and temperature information of the storage compartment and temperature information of the evaporator recorded at a second time point.

[0318] The method may include determining whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan.

[0319] The method may include operating the defrost heater in response to determining that the defrost condition is satisfied.

[0320] The calculating of the index value may include determining a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point.

[0321] The calculating of the index value may include determining a second value by assigning a defined second weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the second time point.

[0322] The calculating of the index value may include determining the index value based on a difference value between the first value and the second value.

[0323] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0324] The method may include determining an oldest time point among the plurality of past time points as the second time point, based on presence of a plurality of past time points that satisfy the defined condition.

[0325] The method may further include omitting calculation of an index value corresponding to the first time point, based on absence of a past time point that satisfies the defined condition.

[0326] The method may further include deleting oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

[0327] The calculating of the index value may include calculating the index value at the defined time intervals, in response to an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

[0328] The determining of whether the defrost condition is satisfied may include determining that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

[0329] The determining of whether the defrost condition is satisfied may include determining that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, and a defined number of consecutive index values calculated at the defined time intervals all being greater than a threshold value.

[0330] The method may further include operating the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, in response to determining that the defrost condition is not satisfied.

[0331] The disclosed embodiments may be implemented in the form of a recording medium that stores instructions executable by a computer. The instructions may be stored in the form of program codes, and when executed by a processor, the instructions may create a program module to perform operations of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

[0332] The computer-readable recording medium may include all kinds of recording media storing instructions that may be interpreted by a computer. For example, the computer-readable recording medium may be a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic tape, a magnetic disk, a flash memory, an optical data storage device, etc.

[0333] In addition, the computer-readable recording medium may be provided in the form of a non-transitory storage medium. Here, when a storage medium is referred to as “non-transitory”, it may be understood that the storage medium is tangible and does not include a signal (e.g., an electromagnetic wave), but rather that data is semi-permanently or temporarily stored in the storage medium. For example, a “non-transitory storage medium” may include a buffer in which data is temporarily stored.

[0334] According to an embodiment, the method according to the one or more embodiments disclosed herein may be provided in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a machine-readable recording medium (e.g., compact disc read only memory (CD-ROM)), or may be distributed (e.g., download or upload) through an application store (e.g., Play Store™) online or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product (e.g., downloadable app) may be stored at least semi-permanently or may be temporarily generated in a recording medium, such as a memory of a server of a manufacturer, a server of an application store, or a relay server.

[0335] Although embodiments of the disclosure have been described with reference to the accompanying drawings, a person having ordinary skilled in the art will appreciate that other specific modifications may be made without departing from the technical spirit or essential features of the disclosure. Therefore, the foregoing embodiments should be regarded as illustrative rather than limiting in all aspects.

Examples

Embodiment Construction

[0034]Various embodiments of the disclosure and terms used herein are not intended to limit the technical features described herein to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of the corresponding embodiments.

[0035]In describing of the drawings, similar reference numerals may be used for similar or related elements.

[0036]The singular form of a noun corresponding to an item may include one or more of the items unless clearly indicated otherwise in a related context.

[0037]In the disclosure, phrases, such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one or all possible combinations of the items listed together in the corresponding phrase among the phrases.

[0038]As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0039]Terms such as “1st”, “2nd”,...

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation application of International Application No. PCT / KR2023 / 020486, filed on Dec. 13, 2023, which claims priority to Korean Patent Application No. 10-2023-0020982, filed on Feb. 16, 2023, in the Korean Intellectual Property Office, the disclosures of which are incorporated by reference herein in their entireties.BACKGROUND1. Field

[0002] The disclosure relates to a refrigerator that may efficiently operate a defrost heater and a method for controlling the refrigerator.2. Description of Related Art

[0003] A refrigerator is a device for storing items such as food, beverages, etc., for a long period without spoilage, and the refrigerator includes a plurality of storage compartments (e.g., a refrigerating compartment, a freezing compartment, a temperature conversion compartment) capable of storing the items.

[0004] The refrigerator repeatedly performs a cooling cycle of compression-condensation-expansion-evaporation of a refrigerant to maintain the temperature of the storage compartment at a set target temperature. That is, the refrigerator supplies each storage compartment with air cooled by an evaporator corresponding to each storage compartment based on a target temperature of each storage compartment, thereby maintaining each storage compartment at its target temperature.

[0005] Water vapor introduced into the refrigerator from outside at room temperature, or water vapor evaporated from food stored in the refrigerator may form frost on an outer surface of the evaporator at a low temperature due to a temperature difference. In addition, frost on the evaporator's surface may reduce heat exchange efficiency, causing decreased cooling efficiency and increased power consumption.SUMMARY

[0006] Provided is a refrigerator that may efficiently remove frost formed on an evaporator, and a method for controlling the refrigerator.

[0007] Further, provided is a refrigerator that may economically operate a defrost heater, and a method for controlling the refrigerator.

[0008] Technical aspects that can be achieved by the disclosure are not limited to the above-mentioned aspects, and other technical aspects not mentioned will be clearly understood by one of ordinary skill in the technical art to which the disclosure belongs from the following description.

[0009] According to an aspect of the disclosure, there is provided a refrigerator including a storage compartment; an evaporator; a defrost heater provided around the evaporator; a compressor configured to compress a refrigerant discharged from the evaporator; a fan configured to supply air cooled by the evaporator to the storage compartment; at least one memory storing instructions and configured to record temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and at least one processor, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to: identify an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point; identify whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and operate the defrost heater based on identifying that the defrost condition is satisfied.

[0010] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to: identify a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point; identify a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; and identify the index value based on the difference value between the first value and the second value.

[0011] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and wherein the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0012] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to, based on a presence of a plurality of past time points that satisfy the defined condition, identify an oldest time point among the plurality of past time points as the second time point.

[0013] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to, based on an absence of a past time point that satisfies the defined condition, omit identifying the index value corresponding to the first time point.

[0014] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to delete oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

[0015] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to identify the index value at the defined time intervals, based on an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

[0016] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

[0017] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, and a defined number of consecutive index values identified at the defined time intervals all being greater than a threshold value.

[0018] The instructions, when executed by the at least one processor individually or collectively, may cause the refrigerator to operate the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, based on identifying that the defrost condition is not satisfied.

[0019] According to an aspect of the disclosure, there is provided a method for controlling a refrigerator including a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator; and a fan configured to supply air cooled by the evaporator to the storage compartment, the method including: recording temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; identifying an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point; identifying whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; and operating the defrost heater based on identifying that the defrost condition is satisfied.

[0020] The identifying of the index value may include: identifying a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point; identifying a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; and identifying the index value based on the difference value between the first value and the second value.

[0021] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and wherein the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0022] The method may include, based on presence of a plurality of past time points that satisfy the defined condition, identifying an oldest time point among the plurality of past time points as the second time point.

[0023] The method may include: based on an absence of a past time point that satisfies the defined condition, omitting the identifying of the index value corresponding to the first time point.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other aspects, features, and advantages of embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0025] FIG. 1 is an external view of a refrigerator according to an embodiment of the disclosure;

[0026] FIG. 2 is a cross-sectional view of a refrigerator according to an embodiment of the disclosure;

[0027] FIG. 3 and FIG. 4 are diagrams for illustrating a cooling device of a refrigerator according to an embodiment of the disclosure;

[0028] FIG. 5 is an example of a control block diagram of a refrigerator according to an embodiment of the disclosure;

[0029] FIG. 6 is a flowchart illustrating an example of a method for controlling a refrigerator according to an embodiment of the disclosure;

[0030] FIG. 7 is a diagram illustrating an example of a method for controlling a refrigerator over time according to an embodiment of the disclosure;

[0031] FIG. 8 illustrates an example of predetermined information recorded by a refrigerator according to an embodiment of the disclosure;

[0032] FIG. 9 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure; and

[0033] FIG. 10 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure.DETAILED DESCRIPTION

[0034] Various embodiments of the disclosure and terms used herein are not intended to limit the technical features described herein to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of the corresponding embodiments.

[0035] In describing of the drawings, similar reference numerals may be used for similar or related elements.

[0036] The singular form of a noun corresponding to an item may include one or more of the items unless clearly indicated otherwise in a related context.

[0037] In the disclosure, phrases, such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one or all possible combinations of the items listed together in the corresponding phrase among the phrases.

[0038] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0039] Terms such as “1st”, “2nd”, “primary”, or “secondary” may be used simply to distinguish an element from other elements, without limiting the element in other aspects (e.g., importance or order).

[0040] Further, as used in the disclosure, the terms “front”, “rear”, “top”, “bottom”, “side”, “left”, “right”, “upper”, “lower”, and the like are defined with reference to the drawings, and are not intended to limit the shape and position of any element.

[0041] It will be understood that when the terms “includes”, “comprises”, “including”, and / or “comprising” are used in the disclosure, they specify the presence of the specified features, figures, steps, operations, components, members, or combinations thereof, but do not preclude the presence or addition of one or more other features, figures, steps, operations, components, members, or combinations thereof.

[0042] When a given element is referred to as being “connected to”, “coupled to”, “supported by” or “in contact with” another element, it is to be understood that it may be directly or indirectly connected to, coupled to, supported by, or in contact with the other element. When a given element is indirectly connected to, coupled to, supported by, or in contact with another element, it is to be understood that it may be connected to, coupled to, supported by, or in contact with the other element through a third element.

[0043] It will also be understood that when an element is referred to as being “on” another element, it may be directly on the other element or intervening elements may also be present.

[0044] A refrigerator according to an embodiment of the disclosure may include a main body.

[0045] The “main body” may include an inner case, an outer case positioned outside the inner case, and an insulation provided between the inner case and the outer case.

[0046] The “inner case” may include a case, a plate, a panel, or a liner forming a storage compartment (also referred to as a storage room). The inner case may be formed as one body, or may be formed by assembling a plurality of plates together. The “outer case” may form an appearance of the main body, and be coupled to an outer side of the inner case such that the insulation is positioned between the inner case and the outer case.

[0047] The “insulation” may insulate an inside of the storage compartment from an outside of the storage compartment to maintain inside temperature of the storage compartment at appropriate temperature without being influenced by an external environment of the storage compartment. According to an embodiment of the disclosure, the insulation may include a foaming insulation. The foaming insulation may be molded by fixing the inner case and the outer case with jigs, etc. and then injecting and foaming urethane foam as a mixture of polyurethane and a foaming agent between the inner case and the outer case.

[0048] According to an embodiment of the disclosure, the insulation may include a vacuum insulation in addition to a foaming insulation, or may be configured only with a vacuum insulation instead of a forming insulation. The vacuum insulation may include a core material and a cladding material accommodating the core material and sealing the inside with vacuum or pressure close to vacuum. However, the insulation is not limited to the above-mentioned foaming insulation or vacuum insulation, and may include various materials capable of being used for insulation.

[0049] The “storage compartment” may include a space defined by the inner case. The storage compartment may further include the inner case defining the space corresponding to the storage compartment. The storage compartment may store a variety of items, such as food, medicines, cosmetics, and the like, and the storage compartment may be configured to be open on at least one side for insertion and removal of the items.

[0050] The refrigerator may include one or more storage compartments. In a case in which two or more storage compartments are formed in the refrigerator, the respective storage compartments may have different purposes of use, and may be maintained at different temperatures. To this end, the respective storage compartments may be partitioned by a partition wall including an insulation.

[0051] The storage compartment may be maintained within an appropriate temperature range according to a purpose of use, and may include a “refrigerating compartment”, a “freezing compartment”, and a “temperature conversion compartment” according to purposes of use and / or temperature ranges. The refrigerating compartment may be maintained at an appropriate temperature to keep food refrigerating, and the freezing compartment may be maintained at an appropriate temperature to keep food frozen. The “refrigerating” may be keeping food cold without freezing the food, and for example, the refrigerating compartment may be maintained within a range of 0 degrees Celsius to 7 degrees Celsius. The “freezing” may be freezing food or keeping food frozen, and for example, the freezing compartment may be maintained within a range of −20 degrees Celsius to −1 degrees Celsius. The temperature conversion compartment may be used as either a refrigerating compartment or a freezing compartment according to or regardless of a user's selection.

[0052] The storage compartment may also be referred to by various terms, such as “vegetable compartment”, “freshness compartment”, “cooling compartment”, and “ice-making compartment”, in addition to “refrigerating compartment”, “freezing compartment”, and “temperature conversion compartment”, and the terms, such as “refrigerating compartment”, “freezing compartment”, “temperature conversion compartment”, etc., as used below are to be understood as representing storage compartments having the corresponding purposes of use and the corresponding temperature ranges.

[0053] The refrigerator according to an embodiment of the disclosure may include at least one door configured to open or close the open side of the storage compartment. The respective doors may be provided to open and close one or more storage compartments, or a single door may be provided to open and close a plurality of storage compartments. The door may be rotatably or slidably mounted to the front of the main body.

[0054] The “door” may seal the storage compartment in a closed state. The door, like the main body, may include an insulation to insulate the storage compartment in a closed state.

[0055] According to an embodiment, the door may include an outer door plate forming the front surface of the door, an inner door plate forming the rear surface of the door and facing the storage compartment, an upper cap, a lower cap, and a door insulation provided therein.

[0056] A gasket may be provided on the edge of the inner door plate to seal the storage compartment by coming into close contact with the front surface of the main body when the door is closed. The inner door plate may include a dyke that protrudes rearward to allow a door basket for storing items to be fitted.

[0057] According to an embodiment, the door may include a door body and a front panel that is detachably coupled to the front of the door body and forming the front surface of the door. The door body may include an outer door plate forming the front surface of the door body, an inner door plate forming the rear surface of the door body and facing the storage compartment, an upper cap, a lower cap, and a door insulator provided therein.

[0058] The refrigerator may be classified as French Door Type, Side-by-side Type, Bottom Mounted Freezer (BMF), Top Mounted Freezer (TMF), or Single Door Refrigerator according to the arrangement of the doors and the storage compartments.

[0059] The refrigerator according to an embodiment of the disclosure may include a cold air supply device for supplying cold air to the storage compartment.

[0060] The “cold air supply device” may include a machine, an apparatus, an electronic device, and / or a combination system thereof, capable of generating cold air and guiding the cold air to cool the storage compartment.

[0061] According to an embodiment of the disclosure, the cold air supply device may generate cold air through a cooling cycle including compression, condensation, expansion, and evaporation processes of refrigerants. To this end, the cold air supply device may include a refrigeration cycle device having a compressor, a condenser, an expander, and an evaporator to drive the refrigeration cycle. According to an embodiment of the disclosure, the cold air supply device may include a semiconductor, such as a thermoelectric element. The thermoelectric element may cool the storage compartment by heating and cooling actions through the Peltier effect.

[0062] The refrigerator according to an embodiment of the disclosure may include a machine compartment in which at least some components belonging to the cold air supply device are installed.

[0063] The “machine compartment” may be partitioned and insulated from the storage compartment to prevent heat generated by the components installed in the machine compartment from being transferred to the storage compartment. To dissipate heat from the components installed in the machine compartment, the machine compartment may communicate with outside of the main body.

[0064] The refrigerator according to an embodiment of the disclosure may include a dispenser provided on the door to provide water and / or ice. The dispenser may be provided on the door to allow access by the user without opening the door.

[0065] The refrigerator according to an embodiment of the disclosure may include an ice-making device that produces ice. The ice-making device may include an ice-making tray that stores water, an ice-moving device that separates ice from the ice-making tray, and an ice-bucket that stores ice produced in the ice-making tray.

[0066] The refrigerator according to an embodiment of the disclosure may include a controller for controlling the refrigerator.

[0067] The “controller” may include a memory for storing and / or recording data and / or programs for controlling the refrigerator, and a processor for outputting control signals for controlling the cold air supply device, etc. in accordance with the programs and / or data stored in the memory.

[0068] The memory may store or record various information, data, instructions, programs, and the like necessary for operation of the refrigerator. The memory may store temporary data generated while generating control signals for controlling components included in the refrigerator. The memory may include at least one of a volatile memory or a non-volatile memory, or a combination thereof.

[0069] The processor may control the overall operation of the refrigerator. The processor may control the components of the refrigerator by executing programs stored in memory. The processor may include a separate neural processing unit (NPU) that performs an artificial intelligence (AI) model operation. In addition, the processor may include a central processing unit (CPU), a graphics processor (GPU), and the like. The processor may generate a control signal to control the operation of the cold air supply device. For example, the processor may receive temperature information of the storage compartment from a temperature sensor and generate a cooling control signal to control an operation of the cold air supply device based on the temperature information of the storage compartment.

[0070] Furthermore, the processor may process a user input of a user interface and control an operation of the user interface in accordance with the programs and / or data memorized / stored in the memory. The user interface may be provided with an input interface and an output interface. The processor may receive the user input from the user interface. In addition, the processor may transmit a display control signal and image data for displaying an image on the user interface to the user interface in response to (e.g., based on) the user input.

[0071] The processor and memory may be provided integrally or may be provided separately. The processor may include one or more processors. For example, the processor may include a main processor and at least one sub-processor. The memory may include one or more memories.

[0072] The refrigerator according to an embodiment of the disclosure may include a processor and a memory for controlling all of the components included in the refrigerator, and may include a plurality of processors and a plurality of memories for individually controlling the components of the refrigerator. For example, the refrigerator may include a processor and a memory for controlling the operation of the cold air supply device in accordance with to an output of the temperature sensor. In addition, the refrigerator may be separately provided with a processor and a memory for controlling the operation of the user interface in accordance with the user input.

[0073] A communication module may communicate with external devices, such as servers, mobile devices, and other home appliances via a nearby access point (AP). The AP may connect a local area network (LAN) to which a refrigerator or a user device is connected to a wide area network (WAN) to which a server is connected. The refrigerator or the user device may be connected to the server via the WAN.

[0074] The input interface may include keys, a touch screen, a microphone, and the like. The input interface may receive the user input and pass the received user input to the processor.

[0075] The output interface may include a display, a speaker, and the like. The output interface may output various notifications, messages, information, and the like generated by the processor.

[0076] Hereinafter, various embodiments according to the disclosure will be described in detail with reference to the accompanying drawings.

[0077] FIG. 1 is an external view of a refrigerator according to an embodiment of the disclosure. FIG. 2 is a cross-sectional view of a refrigerator according to an embodiment of the disclosure.

[0078] Referring to FIG. 1 and FIG. 2, a refrigerator 1 may include a main body 10, storage compartments 20 and 30 formed inside the main body 10, and a cooling device 40 for supplying cold air to the storage compartments 20 and 30.

[0079] The main body 10 may include an inner case 10b that defines the storage compartments 20 and 30, an outer case 10a coupled to an outer side of the inner case 10b to form an exterior of the refrigerator 1, and an insulation 10c arranged between the inner case 10b and the outer case 10a to insulate the storage compartments 20 and 30.

[0080] The storage compartments 20 and 30 may be divided by a middle wall 11 into the upper first storage compartment 20 and the lower second storage compartment 30. The first storage compartment 20 may be maintained at a temperature of approximately 3º° C. to store food refrigerated, and the second storage compartment 30 may be maintained at a temperature of approximately minus 19° C. to store food frozen. The first storage compartment 20 may be provided with shelves on which food may be placed and at least one storage box 24 in which food may be stored.

[0081] The first storage compartment 20 and the second storage compartment 30 each have an open front to put in and take out food, and the open front of the first storage compartment 20 may be opened or closed by a pair of doors (21; 21a, 21b) hinged to the main body 10.

[0082] The open front of the second storage compartment 30 may be opened or closed by at least one door 31 hinged to the main body 10.

[0083] According to various embodiments, the number and type of storage compartments, and the number and type of doors for opening and closing each storage compartment may be changed within a scope of general technology.

[0084] According to various embodiments, the first storage compartment 20 and / or the second storage compartment 30 may include a temperature conversion compartment whose temperature may be changed by a user's setting.

[0085] The cooling device 40 may include an evaporator 41 where liquid refrigerant evaporates, a compressor 42 that compresses gaseous refrigerant, a condenser 43 where gaseous refrigerant condenses, and an expander that expands liquid refrigerant.

[0086] The compressor 42 and the condenser 43 may be installed in a machine compartment provided at a rear lower side of the main body 10.

[0087] The evaporator 41 may be installed in a cooling duct 50 provided at an inner rear side of the storage compartments 20 and 30.

[0088] The cooling duct 50 is provided at the inner rear side of the storage compartments 20 and 30 to allow air to flow. The cooling duct 50 may be provided with a fan 51 for discharging air from which heat has been removed by the evaporator 41 (hereinafter referred to as cold air) into the storage compartments 20 and 30 and drawing air from the storage compartments 20 and 30 into the cooling duct 50.

[0089] An outlet 52 may be formed on an upper side of the cooling duct 50 to allow cold air generated by the evaporator 41 to be discharged to the storage compartments 20 and 30. The outlet 52 may be formed as a plurality of holes.

[0090] An inlet 53 may be formed on a lower side of the cooling duct 50 to allow air from the storage compartments 20 and 30 to be introduced into the cooling duct 50. The inlet 53 may be formed as a plurality of holes.

[0091] Although it has been described that the evaporator 41 is disposed at the rear of the storage compartments 20 and 30 and cold air moves from a lower side to an upper side, the position of the evaporator 41 is not limited thereto. For example, the evaporator 41 may be arranged on a lower surface or an upper surface of the storage compartments 20 and 30 to form a corresponding flow path.

[0092] According to various embodiments, the evaporator 41 may be provided to correspond to each of the storage compartments 20 and 30. For example, the evaporator 41 may include a first evaporator corresponding to the first storage compartment 20 and a second evaporator corresponding to the second storage compartment 30.

[0093] According to various embodiments, a temperature sensor 110 for measuring the temperature of the storage compartments 20 and 30 may be provided in the storage compartments 20 and 30.

[0094] In an embodiment, the temperature sensor 110 may include a temperature sensor 110a for measuring a temperature of the first storage compartment 20 and a temperature sensor 110b for measuring a temperature of the second storage compartment 30.

[0095] The temperature sensor 110 may be disposed inside the storage compartments 20 and 30. For example, the temperature sensor 110 may be disposed near the outlet 52 inside the second storage compartment 30, but the position of the temperature sensor 110 is not limited thereto.

[0096] According to various embodiments, a temperature sensor 120 for measuring a temperature of the evaporator 41 may be provided around the evaporator 41. The temperature sensor 120 for measuring the temperature of the evaporator 41 may be disposed on an upper side of the evaporator 41, but the position of the temperature sensor 120 is not limited thereto.

[0097] According to various embodiments, the temperature sensor 120 may be disposed in a middle region of the evaporator 41.

[0098] According to one or more embodiments, a plurality of temperature sensors 120 may be provided.

[0099] In a case where water vapor flows in near the evaporator 41, frost may form on the evaporator 41.

[0100] In a case where frost forms on the evaporator 41, heat exchange between the air around the evaporator 41 and the refrigerant flowing through the evaporator 41 is hindered, and thus heat exchange efficiency decreases.

[0101] In an embodiment, the refrigerator 1 may include a defrost heater 70 for removing frost formed on the evaporator 41.

[0102] The defrost heater 70 may be provided around the evaporator 41. For example, the defrost heater 70 may be disposed on a lower side of the evaporator, but the position of the defrost heater 70 is not limited thereto.

[0103] The defrost heater 70 may remove ice or frost generated on the evaporator 41 and an outlet of the cooling duct 50, and the like, to allow cold air to be smoothly discharged to the storage compartments 20 and 30.

[0104] The defrost heater 70 may include at least one of a sheath heater, a cord heater, high-temperature gas of the cycle itself, or a heat pump cycle.

[0105] Air heated by the defrost heater 70 rises and moves by convection. Frost formed on the evaporator 41 may be removed by the air heated by the defrost heater 70.

[0106] In an embodiment, during a defrost operation, frost formed on the evaporator 41 may be removed by operating the defrost heater 70.

[0107] In an embodiment, during the defrost operation, the operation of the compressor 42 may be stopped, and thus compressed refrigerant may not be supplied to the evaporator 41.

[0108] In an embodiment, during the defrost operation, the operation of the fan 51 may be stopped to prevent air heated by the defrost heater 70 from being introduced into the storage compartments 20 and 30 through the outlet 52.

[0109] FIG. 3 and FIG. 4 are diagrams for illustrating a cooling device of a refrigerator according to an embodiment of the disclosure.

[0110] In an embodiment, the cooling device 40 may include the evaporator 41 generating cold air through heat exchange, a refrigerant pipe 41a for transferring gaseous refrigerant evaporated in the evaporator 41 to the compressor 42, the compressor 42 compressing the gaseous refrigerant provided through the refrigerant pipe 41a, a refrigerant pipe 42a for transferring the gaseous refrigerant compressed by the compressor 42 to the condenser, and the condenser 43 condensing the refrigerant provided through the refrigerant pipe 42a.

[0111] A motor of the compressor 42 receives a drive current under control of a controller 100, which will be described below, and rotates a rotating shaft through magnetic interaction between a rotor and a stator. A rotational force generated by the motor is converted into a linear motion force by a piston in the compressor 42, and the gaseous refrigerant may be compressed to a high pressure through the linear motion force of the piston. In addition, the rotational force generated by the motor of the compressor 42 may be transmitted to a rotating blade connected to the rotating shaft of the motor, allowing the gaseous refrigerant to be compressed to a high pressure using a stick-slip phenomenon between the rotating blade and a container of the compressor 42.

[0112] The motor of the compressor 42 may include an induction AC servo motor, a synchronous AC servo motor, a brushless direct current (BLDC) motor, or the like.

[0113] Through the pressure by the compressor 42, the refrigerant may circulate through the condenser 43, an expansion valve 45, and the evaporator 41. That is, the compressor 42 performs a vital role in the cooling device 40 that cools the storage compartments 20 and 30. Driving the cooling device 40 may be considered driving the compressor 42.

[0114] According to one or more embodiments, the cooling device 40 may include the condenser 43 for condensing the refrigerant compressed by the compressor 42. When the condenser 43 condenses the refrigerant, the temperature of the condenser 43 may increase due to latent heat released by the refrigerant. In an embodiment, the cooling device 40 may include a heat dissipation fan for cooling the condenser 43.

[0115] According to one or more embodiments, the cooling device 40 may include the expansion valve 45 for expanding the refrigerant condensed in the condenser 43. The expansion valve 45 may reduce the pressure of the high-pressure liquid refrigerant to a pressure that may cause evaporation by a throttling process. The throttling process refers to a reduction in pressure without heat exchange with the outside air when a fluid passes through a narrow flow path such as a nozzle or an orifice.

[0116] The expansion valve 45 may adjust the amount of refrigerant supplied to the evaporator 41 to allow the refrigerant to absorb sufficient heat in the evaporator 41. In addition, the opening and closing and / or an opening degree of the expansion valve 45 may be adjusted by the controller 100, which will be described below.

[0117] The opening and closing of the expansion valve 45 may be controllable.

[0118] For example, the expansion valve 45 may include a thermoelectric electronic expansion valve that uses deformation of a bimetal, a thermostatic electronic expansion valve that uses volumetric expansion by heating enclosed wax, a pulse width modulation type electronic expansion valve for opening or closing a solenoid valve by a pulse signal, or a step motor type electronic expansion valve that uses a motor to open or close the valve.

[0119] The refrigerant that has passed through the expansion valve 45 may be transferred to a capillary tube 43b through a refrigerant pipe 43a and expanded. The capillary tube 43b may be implemented by a thin tube, and may expand high-temperature, high-pressure liquid refrigerant and discharge low-temperature, low-pressure refrigerant mixed with gas and liquid to a refrigerant pipe 43c connected to the evaporator 41.

[0120] According to one or more embodiments, the capillary tube 43b may be omitted.

[0121] Surrounding air may be cooled by the evaporator 41, and the fan 51 may introduce the surrounding air cooled by the evaporator 41 into the storage compartments 20 and 30.

[0122] The low-pressure gaseous refrigerant evaporated by the evaporator 41 may be provided to the compressor 42 again, and the cooling cycle may be repeated. That is, the refrigerant may circulate by sequentially passing through the compressor 42, the condenser 43, and the evaporator 41, thereby cooling the storage compartments 20 and 30.

[0123] Inside the storage compartments 20 and 30, the temperature sensor 110 (hereinafter referred to as ‘inside temperature sensor 110’) for measuring the temperature of the storage compartments 20 and 30 may be provided.

[0124] In the cooling duct 50 where the evaporator 41 is installed, the temperature sensor 120 (hereinafter referred to as ‘evaporator temperature sensor 120’) for measuring the temperature of the evaporator 41 may be provided.

[0125] The evaporator temperature sensor 120 may be disposed near the evaporator 41.

[0126] The defrost heater 70 may be located on one side (e.g., a lower part) of the evaporator 41.

[0127] According to one or more embodiments, in a case where the refrigerator 1 includes an ice maker, the cooling device 40 may include a switching valve for transferring refrigerant condensed by the condenser 43 to the evaporator 41 on the icemaker side.

[0128] FIG. 5 is an example of a control block diagram of a refrigerator according to an embodiment of the disclosure.

[0129] Referring to FIG. 5, the refrigerator 1 may include a plurality of controllable electrical components (e.g., the compressor 42, the fan 51, the expansion valve 45, and / or the defrost heater 70), the controller 100 for controlling the plurality of electrical components of the refrigerator (e.g., the compressor 42, the fan 51, the expansion valve 45, and / or the defrost heater 70), the inside temperature sensor 110 for measuring a temperature of the storage compartments 20 and 30, and the evaporator temperature sensor 120 for measuring a temperature of the evaporator 41.

[0130] The controller 100 may include at least one memory storing a program for performing the above-described operations or operations to be described below and various data required to execute the program, and at least one processor that executes the stored program.

[0131] The controller 100 may include hardware such as a central processing unit (CPU), a Micom (e.g., main control unit (MCU), microprocessor unit (MPU)), the at least one memory 102 and the at least one processor 101, and software such as a control program. For example, the controller 100 may include the at least one memory 102 that stores information, algorithms, and / or data in the form of program for controlling the operation of components in the refrigerator, and the at least one processor 101 that performs the above-described operations and operations to be described below using the data and / or information stored in the at least one memory 102. The memory 102 and the processor 101 may each be implemented as separate chips. The processor 101 may include one or more processor chips or one or more processing cores. The memory 102 may include one or more memory chips or one or more memory blocks. In addition, the memory 102 and the processor 101 may be implemented as a single chip or as a plurality of chips.

[0132] The memory 102 may include a volatile memory such as a static random access memory (S-RAM) or a dynamic random access memory (D-RAM), and a non-volatile memory such as a read only memory (ROM), an erasable programmable read only memory (EPROM), or an electrically erasable programmable read only memory (EEPROM).

[0133] A person skilled in the art will readily understand that controlling the compressor 42 in the disclosure may include controlling the motor of the compressor 42, and controlling the fan 51 may include controlling the motor of the fan 51.

[0134] The controller 100 may control the compressor 42 by controlling a driving circuit for driving the compressor 42. The controller 100 may obtain operation information of the compressor 42 from the driving circuit for driving the compressor 42.

[0135] The operation information of the compressor 42 may include information about an operating frequency of the compressor 42 and / or an operation time of the compressor 42.

[0136] The controller 100 may control the fan 51 by controlling a driving circuit for driving the fan 51. The controller 100 may obtain operation information of the fan 51 from the driving circuit for driving the fan 51.

[0137] The operation information of the fan 51 may include information about an operating revolutions per minute (RPM) of the fan 51 and / or an operation time of the fan 51.

[0138] The controller 100 may receive temperature information of the storage compartments 20 and 30 from the inside temperature sensor 110.

[0139] The temperature information of the storage compartments 20 and 30 may include data about temperature value of the storage compartments 20 and 30 measured by the inside temperature sensor 110.

[0140] The controller 100 may receive temperature information of the evaporator 41 from the evaporator temperature sensor 120.

[0141] The temperature information of the evaporator 41 may include data about a temperature value of the evaporator 41 measured by the evaporator temperature sensor 120.

[0142] In an embodiment, the controller 100 may control the compressor 42 and / or the fan 51 based on the temperature of the storage compartments 20 and 30.

[0143] For example, the controller 100 may operate the compressor 42 and the fan 51 in response to the temperature of the storage compartments 20 and 30 being lower than a preset target temperature.

[0144] A cooling operation may be defined as an operation in which the controller 100 operates the compressor 42 and the fan 51.

[0145] As another example, the controller 100 may adjust an opening degree of the expansion valve 45 in response to a temperature change rate of the storage compartments 20 and 30 being lower than a preset target temperature change rate.

[0146] According to one or more embodiments, the controller 100 may operate the defrost heater 70 based on a determination that the evaporator 41 requires defrosting.

[0147] According to one or more embodiments, the controller 100 may stop the operation of the compressor 42 and the fan 51 while the defrost heater 70 is in operation.

[0148] A defrost operation may be defined as an operation in which the controller 100 operates the defrost heater 70.

[0149] For example, the controller 100 may operate the defrost heater 70 for a predetermined time (e.g., 10 minutes) at preset defrost cycles (e.g., 10 hours).

[0150] In an embodiment, the refrigerator 1 may include a door opening / closing sensor for detecting opening and closing of the doors 21 and 31, and the controller 100 may advance the preset defrost cycle based on an opening count and an opening time of the doors 21 and 31.

[0151] Meanwhile, unless the refrigerator 1 is equipped with an expensive sensor capable of accurately detecting the amount of frost formed on the evaporator 41, the amount of frost formed on the evaporator 41 is to be estimated based on factors (e.g., the opening count and opening time of the doors 21 and 31) that may estimate the amount of frost formed on the evaporator 41.

[0152] According to the disclosure, a method that may relatively accurately estimate the amount of frost formed on the evaporator 41 using factors that estimate the amount of frost formed on the evaporator 41 may be provided.

[0153] A relatively accurate estimation of the amount of frost formed on the evaporator 41 may operate the defrost heater 70 economically, thereby increasing energy efficiency.

[0154] In addition, a relatively accurate estimation of the amount of frost formed on the evaporator 41 may allow for an immediate removal of the frost formed on the evaporator 41 when required, thereby increasing the energy efficiency of the cooling device 40.

[0155] Hereinafter, an embodiment of the disclosure is described that may determine (e.g., identify) an optimal operation time of the defrost heater 70 based on alternative factors that may estimate the amount of frost formed on the evaporator 41.

[0156] FIG. 6 is a flowchart illustrating an example of a method for controlling a refrigerator according to an embodiment of the disclosure.

[0157] Referring to FIG. 6, the controller 100 may record predetermined information at defined time intervals (e.g., 10-minute intervals) (1000).

[0158] In an embodiment, the memory 102 may record predetermined information at defined time intervals (e.g., 10-minute intervals).

[0159] Recording predetermined information at defined time intervals may include storing the predetermined information in the memory 102 at defined time intervals.

[0160] Recording predetermined information at defined time intervals may include separately storing, in the memory 102, the predetermined information stored at defined time intervals among information continuously stored in the memory 102.

[0161] According to one or more embodiments, the memory 102 may include a volatile memory and a non-volatile memory.

[0162] Storing predetermined information in the memory 102 at defined time intervals may include storing the predetermined information in a non-volatile memory at defined time intervals.

[0163] Separately storing, in the memory 102, predetermined information stored at defined time intervals among information continuously stored in the memory 102 may include storing, in the non-volatile memory, predetermined information stored at defined time intervals among predetermined information stored in the volatile memory.

[0164] The predetermined information stored in the non-volatile memory at defined time intervals may be copied to the volatile memory when the refrigerator 1 is turned on.

[0165] Separately storing, in the memory 102, predetermined information stored at defined time intervals among information continuously stored in the memory 102 may include separately storing, in the non-volatile memory, predetermined information stored at defined time intervals among predetermined information stored in the non-volatile memory.

[0166] The processor 101 may read the predetermined information recorded in the memory 102 at defined time intervals, and may perform various operations to be described below based on the information.

[0167] Accordingly, recording predetermined information at defined time intervals may include the memory 102 storing predetermined information to be used later by the processor 101.

[0168] In an embodiment, the controller 100 may record temperature information of the storage compartments 20 and 30, temperature information of the evaporator 41, operation information of the compressor 42, and operation information of the fan 51 at defined time intervals.

[0169] The temperature information of the storage compartments 20 and 30 may be obtained from the inside temperature sensor 110, and may include the temperature of the storage compartments 20 and 30.

[0170] The temperature information of the evaporator 41 may be obtained from the evaporator temperature sensor 120, and may include the temperature of the evaporator 41.

[0171] The operation information of the compressor 42 may be obtained from a driving circuit that drives the compressor 42, and may include an operation time and / or operating frequency of the compressor 42.

[0172] The operation information of the fan 51 may be obtained from a driving circuit that drives the fan 51, and may include an operation time and / or operating RPM of the fan 51.

[0173] According to one or more embodiments, the controller 100 may record operation information of the expansion valve 45 at defined time intervals.

[0174] The operation information of the expansion valve 45 may include an open / closed state of the expansion valve 45.

[0175] In an embodiment, the controller 100 may record predetermined information in the memory 102 at defined time intervals.

[0176] According to one or more embodiments, the memory 102 may store up to n pieces of information (where n is a natural number greater than or equal to 2). For example, the memory 102 may store up to 40 pieces of information.

[0177] Assuming the defined time interval is 10 minutes, the memory 102 may record predetermined information for 400 minutes.

[0178] According to one or more embodiments, in a case where the number of pieces of information recorded at defined time intervals exceeds a predetermined number (e.g., 40 pieces), the controller 100 may delete the oldest recorded information.

[0179] According to the disclosure, as the oldest recorded information is deleted, the reliability of the recorded information may be increased.

[0180] The controller 100 may omit the calculation of an index value, in response to an index value calculation condition not being satisfied (No in operation 1100).

[0181] The index value is a value that may be used to detect a defrost condition. In the disclosure, the index value may be used as one factor for determining whether the defrost condition is satisfied.

[0182] The index value calculation condition may include various conditions under which frost formation on the evaporator 41 may be reasonably estimated.

[0183] For example, the index value calculation condition may include an elapse of a preset time (e.g., 10 hours) after a defrost operation ends, i.e., after an operation of the defrost heater 70 is stopped.

[0184] As another example, the index value calculation condition may include an elapse of a preset time (e.g., 5 hours) after the refrigerator 1 is turned on.

[0185] The controller 100 may calculate (e.g., identify) the index value at defined time intervals (1200), in response to the index value calculation condition being satisfied (Yes in operation 1100).

[0186] For example, the controller 100 may calculate the index value at defined time intervals, in response to an elapse of a preset time (e.g., 5 hours or 10 hours) from the time point when the operation of the defrost heater 70 ends and / or the time point when power is applied to the refrigerator 1.

[0187] Before the preset time elapses from the time point when power is applied to the refrigerator 1 and / or the time point when the operation of the defrost heater 70 ends, there is realistically insufficient time for frost to form on the evaporator 41.

[0188] According to the disclosure, by starting to calculate the index value from the time point when frost is expected to form on the evaporator 41, the use of an index value with low reliability may be prevented.

[0189] According to one or more embodiments, the controller 100 may calculate the index value at the defined time intervals in response to a first preset time having elapsed from the time point when the refrigerator 1 was turned on. The time point when the refrigerator 1 was turned on refers to the time point when the refrigerator 1 started receiving power from an external power source.

[0190] According to one or more embodiments, the controller 100 may calculate the index value at the defined time intervals in response to a second preset time having elapsed from the time point when the operation of the defrost heater 70 finished.

[0191] In this instance, the first preset time may be shorter than the second preset time.

[0192] Because the time point when the refrigerator 1 was turned on corresponds to an initial installation time point of the refrigerator 1, a large amount of water vapor is highly likely to have flowed in near the evaporator 41.

[0193] According to the disclosure, by setting the first preset time to be shorter than the second preset time, index values with low reliability may be excluded, and whether frost has formed on the evaporator 41 may be estimated at an optimal time.

[0194] The controller 100 may record predetermined information at defined time intervals, and calculate the index value based on the recorded predetermined information.

[0195] According to one or more embodiments, the controller 100 may calculate the index value, based on temperature information of the storage compartments 20 and 30 and temperature information of the evaporator 41 recorded at the most recent time point and temperature information of the storage compartments 20 and 30 and temperature information of the evaporator 41 recorded at a past time point that satisfies a defined condition.

[0196] In a case where frost forms on the evaporator 41, air heat-exchanged by the evaporator 41 may be trapped by the frost, and thus the temperature of the storage compartments 20 and 30 may not decrease, while the temperature of the evaporator41 may decrease.

[0197] That is, in a case where frost forms on the evaporator 41, a difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30 increases.

[0198] Meanwhile, even in a case where frost does not form on the evaporator 41, the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30 may be increased by many other conditions.

[0199] For example, the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30 may change depending on various factors, such as an operating frequency of the compressor 42, an open / closed state of the expansion valve 45, and / or an operating RPM of the fan 51, regardless of the presence or absence of frost formed on the evaporator 41.

[0200] According to the disclosure, by using not only predetermined information recorded at the most recent time point but also predetermined information recorded at a past time point that satisfies a defined condition, whether frost has formed on the evaporator 41 may be robustly estimated based on various factors that may change the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30, in addition to the frost formed on the evaporator 41.

[0201] According to one or more embodiments, the controller 100 may determine whether the defrost condition is satisfied based on the index value (1300).

[0202] The controller 100 may operate the defrost heater 70 (1400), in response to determining that the defrost condition is satisfied (Yes in operation 1300).

[0203] The controller 100 may add a predetermined additional time k2 (e.g., approximately 15 hours) to a preset defrost cycle k1 (1350), in response to determining that the defrost condition is not satisfied (No in operation 1300).

[0204] In a case where a time obtained by adding the predetermined additional time k2 to the preset defrost cycle k1 is defined as a preset time (k1+k2), the controller 100 may operate the defrost heater 70 based on a cumulative operation time of the compressor 42 exceeding the preset time (k1+k2) in response to determining that the defrost condition is not satisfied.

[0205] That is, in a case where the defrost condition is not satisfied based on the index value, the controller 100 may operate the defrost heater 70 in response to the cumulative operation time of the compressor 42 exceeding the preset defrost cycle k1 and the predetermined additional time k2 (1400).

[0206] However, in a case where it is determined that the defrost condition is satisfied before the cumulative operation time of the compressor 42 exceeds the preset time (k1+k2), the controller 100 may immediately operate the defrost heater 70.

[0207] According to the disclosure, the defrost heater 70 may be prevented from unnecessarily operating by adding the predetermined additional time k2 to the preset defrost cycle k1 in a case where the defrost condition is not satisfied. Thus, energy efficiency may be improved.

[0208] The defrost heater 70 may be operated for a preset time, and based on an elapse of the preset time, the operation of the defrost heater 70 may be stopped to complete the defrost operation (1500).

[0209] For example, the defrost heater 70 may operate until the temperature of the evaporator 41 measured by the evaporator temperature sensor 120 reaches a predetermined temperature. As another example, an operation time of the defrost heater 70 may vary depending on the estimated amount of frost, as described below.

[0210] That is, in a case where the estimated amount of frost on the evaporator 41 is large, the operation time of the defrost heater 70 may be lengthened, and in a case where the estimated amount of frost on the evaporator 41 is small, the operation time of the defrost heater 70 may be shortened.

[0211] When the defrost operation is completed, the controller 100 may perform from operation 1100 again.

[0212] An embodiment in which the controller 100 determines whether the defrost condition is satisfied based on the index value will be described below with reference to FIG. 8 to FIG. 10.

[0213] According to one or more embodiments, some of the operations shown in FIG. 6 may be omitted, and some operations may be added. In addition, the order of the operations shown in FIG. 6 may change.

[0214] FIG. 7 is a diagram illustrating an example of a method for controlling a refrigerator over time according to an embodiment of the disclosure.

[0215] Referring to FIG. 7, the controller 100 may record predetermined information at defined time intervals from a time point t1 when the refrigerator 1 is turned on (operation 1000 of FIG. 6).

[0216] The controller 100 may calculate an index value at defined time intervals in response to an index value calculation condition being satisfied.

[0217] For example, the controller 100 may calculate the index value at defined time intervals (operation 1200 of FIG. 6), in response to a first preset time h1 (e.g., approximately 5 hours) having elapsed from the time point t1 when the refrigerator 1 was turned on (Yes in operation 1100 of FIG. 6).

[0218] That is, the controller 100 may calculate the index value at defined time intervals from a time point t2 when the first preset time h1 has elapsed from the time point t1 when the refrigerator 1 was turned on.

[0219] The controller 100 may determine whether the defrost condition is satisfied based on the index value (operation 1300 of FIG. 6).

[0220] The controller 100 may operate the defrost heater 70 (operation 1400 of FIG. 6), in response to determining that the defrost condition is satisfied (Yes in operation 1300 of FIG. 6).

[0221] That is, the controller 100 may operate the defrost heater 70 at a time point t3 when it is determined that the defrost condition is satisfied.

[0222] The controller 100 may operate the defrost heater 70 for a predetermined time, and stop the operation of the defrost heater 70 in response to the elapse of the predetermined time, thereby ending the defrost operation (operation 1500 of FIG. 6).

[0223] The controller 100 may calculate the index value at defined time intervals in response to the index value calculation condition being satisfied.

[0224] For example, the controller 100 may calculate the index value at defined time intervals, in response to a second preset time h2 (e.g., approximately 5 hours) having elapsed from a time point t4 when the operation of the defrost heater 70 was stopped.

[0225] That is, the controller 100 may calculate the index value at defined time intervals from a time point t5 when the second preset time h2 has elapsed from the time point t4 when the operation of the defrost heater 70 was stopped.

[0226] As such, according to the disclosure, operations 1100, 1200, 1300, 1350, 1400, and 1500 of FIG. 6 may be repeatedly performed.

[0227] FIG. 8 illustrates an example of predetermined information recorded by a refrigerator according to an embodiment of the disclosure.

[0228] Referring to FIG. 8, predetermined information recorded at defined time intervals by the refrigerator 1 according to an embodiment may be confirmed.

[0229] Hereinafter, for convenience of description, it is defined that information arranged at a lower side is closer to the present, and information arranged at an upper side is closer to the past.

[0230] According to one or more embodiments, the controller 100 may collect predetermined information at defined time intervals (e.g., 10 minutes).

[0231] In an embodiment, the predetermined information may include temperature information of the storage compartments 20 and 30, temperature information of the evaporator 41, operation information of the compressor 42, and operation information of the fan 51.

[0232] According to one or more embodiments, the predetermined information may further include operation information of the expansion valve 45.

[0233] Assuming that the information arranged in each row constitutes one piece of information, in a case where the number of pieces of information recorded at defined time intervals exceeds a predetermined number (e.g., 40), the controller 100 may delete the oldest recorded information among the information recorded at defined time intervals, and new information may be updated.

[0234] For example, assuming that the predetermined number is 40, the information in the first row may be deleted at each defined time interval, and new information may be added to the last row.

[0235] According to one or more embodiments, the controller 100 may record information only when reliability is ensured. For example, the controller 100 may record the temperature information of the evaporator 41 and the temperature information of the storage compartments 20 and 30 only when a temperature of the evaporator 41 and / or a temperature of the storage compartments 20 and 30 fluctuates within a predetermined range for a predetermined time (e.g., approximately 1 minute). As another example, the controller 100 may record the operation information of the compressor 42 only when an operating frequency of the compressor 42 fluctuates within a predetermined range for a predetermined time (e.g., approximately 1 minute). As still another example, the controller 100 may record the operation information of the fan 51 only when an operating RPM of the fan 51 fluctuates within a predetermined range for a predetermined time (e.g., approximately 1 minute). As yet another example, the controller 100 may record the operation information of the expansion valve 45 only when an open / closed state of the expansion valve 45 is maintained for a predetermined time (e.g., approximately 1 minute).

[0236] According to the disclosure, the reliability of information recorded at defined time intervals may be secured.

[0237] In an embodiment, the controller 100 may calculate an index value based on the information recorded at defined time intervals.

[0238] To calculate the index value, the controller 100 may determine a past time point that satisfies a defined condition.

[0239] In an embodiment, the defined condition may include the operation information of the compressor 42 and the operation information of the fan 51 recorded at the past time point being identical to the operation information of the compressor 42 and the operation information of the fan 51 recorded at the most recent time point.

[0240] In this instance, the operation information of the compressor 42 being identical may include the operating frequencies of the compressor 42 being identical.

[0241] The operation information of the fan 51 being identical may include the operating RPMs of the fan 51 being identical.

[0242] According to one or more embodiments, the defined condition may include the operation information of the expansion valve 45 recorded at the past time point being identical to the operation information of the expansion valve 45 recorded at the most recent time point.

[0243] The operation information of the expansion valve 45 being identical may include the open / closed state of the expansion valve 45 being identical.

[0244] For example, in a case where operation information c40 of the compressor 42 and operation information d40 of the fan 51 recorded at the most recent time point P40 are identical to operation information c3 of the compressor 42 and operation information d3 of the fan 51 recorded at a past time point P3, respectively, the controller 100 may determine that the past time point P3 satisfies the defined condition.

[0245] As another example, in a case where the operation information c40 of the compressor 42, the operation information d40 of the fan 51, and operation information e40 of the expansion valve 45 recorded at the most recent time point P40 are identical to operation information c1 of the compressor 42, operation information d1 of the fan 51, and operation information e1 of the expansion valve 45 recorded at a past time point P1, respectively, the controller 100 may determine that the past time point P1 satisfies the defined condition.

[0246] According to one or more embodiments, in a case where a plurality of past time points that satisfy the defined condition exist, the controller 100 may determine the oldest time point among the plurality of past time points that satisfy the defined condition as the past time point that satisfies the defined condition.

[0247] In other words, in a case where there are a plurality of past time points that satisfy the defined condition, the controller 100 may calculate the index value based on the temperature information of the storage compartments 20 and 30 and the temperature information of the evaporator 41 recorded at the oldest time point among the plurality of past time points.

[0248] For example, in a case where the operation information c40 of the compressor 42 and the operation information d40 of the fan 51 recorded at the most recent time point P40 are identical to the operation information c3 of the compressor 42 and the operation information d3 of the fan 51 recorded at the first past time point P3, respectively, and the operation information c40 of the compressor 42 and the operation information d40 of the fan 51 recorded at the most recent time point P40 are identical to the operation information c2 of the compressor 42 and the operation information d2 of the fan 51 recorded at a second past time point P2, respectively, the controller 100 may determine that the second past time point P2, which is older than the first past time point P3, satisfies the defined condition.

[0249] As another example, in a case where the operation information c40 of the compressor 42, the operation information d40 of the fan 51, and the operation information e40 of the expansion valve 45 recorded at the most recent time point P40 are identical to the operation information c3 of the compressor 42, the operation information d3 of the fan 51, and operation information e3 of the expansion valve 45 recorded at the first past time point P3, respectively, and the operation information c40 of the compressor 42, the operation information d40 of the fan 51, and the operation information e40 of the expansion valve 45 recorded at the most recent time point P40 are identical to the operation information c2 of the compressor 42, the operation information d2 of the fan 51, and operation information e2 of the expansion valve 45 recorded at the second past time point P2, respectively, the controller 100 may determine that the second past time point P2, which is older than the first past time point P3, satisfies the defined condition.

[0250] The controller 100 may calculate the index value based on the temperature information of the storage compartments 20 and 30 and the temperature information of the evaporator 41 recorded at the past time point that satisfies the defined condition, and the temperature information of the storage compartments 20 and 30 and the temperature information of the evaporator 41 recorded at the most recent time point.

[0251] The index value may be calculated by [Equation 1] below.index=L1(a-b)-L2(c-d)[Equation⁢ 1]

[0252] Here, index denotes the index value, L1 denotes a defined first weight, L2 denotes a defined second weight, a denotes a temperature value of the evaporator 41 recorded at the most recent time point, b denotes a temperature value of the storage compartments 20 and 30 recorded at the most recent time point, c denotes a temperature value of the evaporator 41 recorded at a past time point that satisfies the defined condition, and d denotes a temperature value of the storage compartments 20 and 30 recorded at a past time point that satisfies the defined condition.

[0253] In an embodiment, the controller 100 may determine a first value L1 (a−b) by assigning the defined first weight L1 to a difference value (a−b) between the temperature value a of the evaporator 41 and the temperature value b of the storage compartments 20 and 30 recorded at the most recent time point, and may determine a second value L2(c−d) by assigning the defined second weight L2 to a difference value (c−d) between the temperature value c of the evaporator 41 and the temperature value d of the storage compartments 20 and 30 recorded at a past time point that satisfies the defined condition. In addition, the controller 100 may determine the index value based on a difference value (L1(a−b)−L2(c−d)) between the first value and the second value.

[0254] The first weight L1 and the second weight L2 may be set according to characteristics of the refrigerator 1. According to one or more embodiments, optimal values for the first weight L1 and the second weight L2 may be set through machine learning. For example, the first weight L1 and the second weight L2 may be set to 0.5 and 0.3, respectively, but are not limited thereto.

[0255] In an embodiment, the first weight L1 may be greater than the second weight L2.

[0256] In a case where the first weight L1 is greater than the second weight L2, a temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the most recent time point and a temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the past time point may be considered.

[0257] For example, [Equation 1] may be reproduced as [Equation 2] below.index=(L1-L2)⁢(a-b)+L2((a-b-(c-d))[Equation⁢ 2]

[0258] In a case where the first weight L1 is greater than the second weight L2, the temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the most recent time point may be considered, and at the same time, ‘the temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the most recent time point and the temperature difference between the evaporator 41 and the storage compartments 20 and 30 at the past time point’ may also be considered to calculate the index value.

[0259] According to the disclosure, the index value may be calculated using not only information at the current time point but also information at a past time point having the same condition, thereby robustly estimating whether frost has formed on the evaporator 41 based on various factors that may change the difference value between the temperature of the evaporator 41 and the temperature of the storage compartments 20 and 30, in addition to the frost formed on the evaporator 41.

[0260] For example, assuming that a past time point that satisfies the defined condition for the most recent time point P40 is the time point P1, an index value f2 corresponding to the most recent time point P40 may be calculated by [Equation 3] below.f2=L1(a4⁢0-b4⁢0)-L2(a1-b1)[Equation⁢ 3]

[0261] As another example, it is assumed that a past time point that satisfies the defined condition for a specific time point P39 is the time point P2.

[0262] In other words, it is assumed that operation information c39 of the compressor 42, operation information d39 of the fan 51, and operation information e39 of the expansion valve 45 recorded at the specific time point P39 are identical to the operation information c2 of the compressor 42, the operation information d2 of the fan 51, and the operation information e2 of the expansion valve 45 recorded at the specific past time point P2, respectively.

[0263] Assuming that a past time point that satisfies the defined condition for the specific time point P39 is the time point P2, an index value f1 corresponding to the specific time point P39 may be calculated by [Equation 4] below.f1=L1(a3⁢9-b3⁢9)-L2(a2-b2)[Equation⁢ 4]

[0264] According to an embodiment, the index value for detecting the defrost condition may be calculated at defined time intervals at which predetermined information is recorded.

[0265] Because recording information and calculating the index value may be performed at defined time intervals once the index value calculation condition is satisfied, information about the index value corresponding to each information recording time point P39 and P40 may also be recorded together as information corresponding to each recording time point P39 and P40.

[0266] In general, when the refrigerator 1 is in operation, a past time point that satisfies the defined condition exists. However, in a case where no past time point that satisfies the defined condition exists, an error may occur during the index value calculation.

[0267] In an embodiment, in a case where no past time point satisfies the defined condition, the controller 100 may omit the calculation of the index value corresponding to the most recent time point.

[0268] According to the disclosure, an error that may occur while calculating the index value in a case where no past time point that satisfies the defined condition exists may be prevented.

[0269] As described above, the controller 100 may determine whether the defrost condition is satisfied based on the index value.

[0270] In an embodiment, the controller 100 may accurately identify an operation time point of the defrost heater 70 by considering other alternative factors together with the index value.

[0271] In an embodiment, the controller 100 may determine whether the defrost condition is satisfied based on the index value, the operation information of the compressor 42, and the operation information of the fan 51.

[0272] For example, as an alternative factor for estimating the amount of frost formed on the evaporator 41, a continuous operation time of the compressor 42 may be used. In a case where frost forms on the evaporator 41, the temperature of the storage compartments 20 and 30 may not reach a target temperature, and thus the compressor 42 may operate continuously.

[0273] The controller 100 may count an operation time of the compressor 42, and determine that part of the defrost condition is satisfied in response to the compressor 42 operating continuously for a preset time (e.g., approximately 2 hours).

[0274] As an alternative factor for estimating the amount of frost formed on the evaporator 41, a change in the rotation speed of the fan 51 may be used. In a case where frost forms on the evaporator 41, a flow rate in the storage compartments 20 and 30 may decrease, and thus the rotation speed of the fan 51 may fluctuate.

[0275] For example, in a case where frost forms on the evaporator 41 and the flow rate in the storage compartments 20 and 30 decreases, the rotation speed of the fan 51 may increase.

[0276] In an embodiment, the controller 100 may measure the rotation speed of the fan 51 during a first cooling operation after the operation of the defrost heater 70 ends, and may record the measured rotation speed of the fan 51 in the memory 102 as a reference rotation speed.

[0277] The controller 100 may compare the rotation speed of the fan 51 with the reference rotation speed recorded in the memory 102 at defined time intervals, and may determine that part of the defrost condition is satisfied in response to a difference value between the rotation speed of the fan 51 and the reference rotation speed recorded in the memory 102 being greater than a predetermined value. In other words, the controller 100 may determine that part of the defrost condition is satisfied in response to the rotation speed of the fan 51 being greater than a threshold rotation speed. Here, the threshold rotation speed may be a speed obtained by adding a speed corresponding to the predetermined value to the reference rotation speed recorded in the memory 102.

[0278] According to one or more embodiments, the controller 100 may determine whether part of the defrost condition is satisfied based on the index value calculated at defined time intervals.

[0279] According to one or more embodiments, the controller 100 may determine that the defrost condition is satisfied in response to at least one of the defrost conditions being satisfied.

[0280] A plurality of defrost conditions may exist and may be set according to characteristics of the refrigerator 1.

[0281] According to one or more embodiments, the defrost condition may be set to an optimal condition through machine learning.

[0282] Hereinafter, an example of the defrost condition is described with reference to FIG. 9 and FIG. 10. However, the defrost condition may be changed and added according to characteristics of the refrigerator 1.

[0283] FIG. 9 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure. FIG. 10 is a diagram for illustrating an example of a defrost condition according to an embodiment of the disclosure.

[0284] Referring to FIG. 9, a defrost condition according to an embodiment may include continuous operation of the compressor 42 for a preset time (e.g., approximately 2 hours), a rotation speed of the fan 51 being greater than a threshold rotation speed, and an index value corresponding to the most recent time point P40 being greater than a threshold value. In this instance, the preset time and / or the threshold rotation speed and / or the threshold value may be set in advance, and may vary depending on characteristics of the refrigerator 1. For example, the preset time may be set to approximately 1 hour and 30 minutes and the threshold value may be set to approximately 11, but is not limited thereto.

[0285] For example, the preset time and / or the threshold rotation speed and / or the threshold value may be set to an optimal value derived through machine learning.

[0286] In an embodiment, the controller 100 may determine that the defrost conditions are satisfied, based on the compressor 42 operating for the preset time, the rotation speed of the fan 51 being greater than the defined threshold rotation speed, and the index value corresponding to the most recent time point being greater than or equal to the threshold value.

[0287] Referring to FIG. 10, the defrost condition according to an embodiment may include continuous operation of the compressor 42 for a preset time (e.g., approximately 2 hours), and a predetermined number (e.g., 3) of consecutive index values calculated at defined time intervals all being greater than a threshold value.

[0288] The predetermined number of consecutive index values calculated at defined time intervals may include an index value corresponding to the most recent time point P40, and may include at least one index value corresponding to at least one previous time point P39 and P38.

[0289] In this instance, the preset time and / or the predetermined number and / or the threshold value may be set in advance, and may vary depending on characteristics of the refrigerator 1.

[0290] For example, the preset time and / or the predetermined number and / or the threshold value may be set to an optimal value derived through machine learning.

[0291] Assuming the predetermined number is 3, the defrost conditions may be satisfied in a case where the index values calculated at the three most recent consecutive time points P40, P39, and P38 are all greater than the threshold value and the compressor 42 is operating continuously for the preset time (e.g., approximately 2 hours).

[0292] In an embodiment, the controller 100 may determine that the defrost conditions are satisfied in response to the compressor 42 operating continuously for the preset time and the predetermined number of consecutive index values calculated at defined time intervals all being greater than the threshold value.

[0293] However, the defrost condition is not limited to the conditions described above.

[0294] For example, the controller 100 may determine that the defrost condition is satisfied in response to a predetermined number (e.g., 5) of consecutive index values calculated at defined time intervals all being greater than a threshold value.

[0295] According to one or more embodiments, the controller 100 may determine an operation time of the defrost heater 70 based on which of a plurality of defrost conditions is satisfied.

[0296] For example, for convenience of description, it is assumed that a first defrost condition includes continuous operation of the compressor 42 for a preset time and a predetermined number of consecutive index values calculated at defined time intervals all being greater than a threshold value, and a second defrost condition includes continuous operation of the compressor 42 for a preset time, a rotation speed of the fan 51 being greater than a threshold rotation speed, and an index value corresponding to the most recent time point being greater than a threshold value.

[0297] The controller 100 may operate the defrost heater 70 for a first period of time in response to the first defrost condition being satisfied, and may operate the defrost heater 70 for a second period of time longer than the first period of time in response to the second defrost condition being satisfied.

[0298] According to the disclosure, a more reliable result value may be derived by using not only current data but also past data when calculating the index value.

[0299] According to the disclosure, whether frost has formed on the evaporator 41 may be accurately estimated by considering various results that may occur when frost has formed on the evaporator 41.

[0300] According to the disclosure, energy efficiency may be increased by preventing the defrost heater 70 from operating when a defrost operation is not required.

[0301] According to an embodiment of the disclosure, a refrigerator may include; a storage compartment; an evaporator; a defrost heater provided around the evaporator; a compressor configured to compress a refrigerant discharged from the evaporator; a fan configured to supply air cooled by the evaporator to the storage compartment; memory configured to record temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and at least one processor configured to operate the defrost heater in response to determining that a defrost condition is satisfied.

[0302] The at least one processor may be configured to calculate an index value for detecting a defrost condition based on temperature information of the storage compartment and temperature information of the evaporator recorded at a first time point and temperature information of the storage compartment and temperature information of the evaporator recorded at a second time point.

[0303] The at least one processor may be configured to determine whether the defrost condition is satisfied based on the index value.

[0304] The at least one processor may be configured to determine whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan.

[0305] The at least one processor may be configured to operate the defrost heater in response to determining that the defrost condition is satisfied.

[0306] The at least one processor may be configured to determine a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point.

[0307] The at least one processor may be configured to determine a second value by assigning a defined second weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the second time point.

[0308] The at least one processor may be configured to determine the index value based on a difference value between the first value and the second value.

[0309] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0310] The at least one processor may be configured to determine an oldest time point among the plurality of past time points as the second time point, based on presence of a plurality of past time points that satisfy the defined condition.

[0311] The at least one processor may be configured to omit calculation of an index value corresponding to the first time point, based on absence of a past time point that satisfies the defined condition.

[0312] The at least one processor may be configured to delete oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

[0313] The at least one processor may be configured to calculate the index value at the defined time intervals, in response to an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

[0314] The at least one processor may be configured to determine that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

[0315] The at least one processor may be configured to determine that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, and a defined number of consecutive index values calculated at the defined time intervals all being greater than a threshold value.

[0316] The at least one processor may be configured to operate the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, in response to determining that the defrost condition is not satisfied.

[0317] According to an embodiment of the disclosure, in a method for controlling a refrigerator including a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator; and a fan configured to supply air cooled by the evaporator to the storage compartment, the method may include: recording temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; and calculating an index value for detecting a defrost condition based on temperature information of the storage compartment and temperature information of the evaporator recorded at a first time point and temperature information of the storage compartment and temperature information of the evaporator recorded at a second time point.

[0318] The method may include determining whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan.

[0319] The method may include operating the defrost heater in response to determining that the defrost condition is satisfied.

[0320] The calculating of the index value may include determining a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point.

[0321] The calculating of the index value may include determining a second value by assigning a defined second weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the second time point.

[0322] The calculating of the index value may include determining the index value based on a difference value between the first value and the second value.

[0323] The second time point may be a past time point that satisfies a defined condition among time points before the first time point, and the defined condition may include operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

[0324] The method may include determining an oldest time point among the plurality of past time points as the second time point, based on presence of a plurality of past time points that satisfy the defined condition.

[0325] The method may further include omitting calculation of an index value corresponding to the first time point, based on absence of a past time point that satisfies the defined condition.

[0326] The method may further include deleting oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

[0327] The calculating of the index value may include calculating the index value at the defined time intervals, in response to an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

[0328] The determining of whether the defrost condition is satisfied may include determining that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

[0329] The determining of whether the defrost condition is satisfied may include determining that the defrost condition is satisfied, in response to the compressor being in operation for a preset time, and a defined number of consecutive index values calculated at the defined time intervals all being greater than a threshold value.

[0330] The method may further include operating the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, in response to determining that the defrost condition is not satisfied.

[0331] The disclosed embodiments may be implemented in the form of a recording medium that stores instructions executable by a computer. The instructions may be stored in the form of program codes, and when executed by a processor, the instructions may create a program module to perform operations of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

[0332] The computer-readable recording medium may include all kinds of recording media storing instructions that may be interpreted by a computer. For example, the computer-readable recording medium may be a Read Only Memory (ROM), a Random Access Memory (RAM), a magnetic tape, a magnetic disk, a flash memory, an optical data storage device, etc.

[0333] In addition, the computer-readable recording medium may be provided in the form of a non-transitory storage medium. Here, when a storage medium is referred to as “non-transitory”, it may be understood that the storage medium is tangible and does not include a signal (e.g., an electromagnetic wave), but rather that data is semi-permanently or temporarily stored in the storage medium. For example, a “non-transitory storage medium” may include a buffer in which data is temporarily stored.

[0334] According to an embodiment, the method according to the one or more embodiments disclosed herein may be provided in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a machine-readable recording medium (e.g., compact disc read only memory (CD-ROM)), or may be distributed (e.g., download or upload) through an application store (e.g., Play Store™) online or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product (e.g., downloadable app) may be stored at least semi-permanently or may be temporarily generated in a recording medium, such as a memory of a server of a manufacturer, a server of an application store, or a relay server.

[0335] Although embodiments of the disclosure have been described with reference to the accompanying drawings, a person having ordinary skilled in the art will appreciate that other specific modifications may be made without departing from the technical spirit or essential features of the disclosure. Therefore, the foregoing embodiments should be regarded as illustrative rather than limiting in all aspects.

Examples

Embodiment Construction

[0034]Various embodiments of the disclosure and terms used herein are not intended to limit the technical features described herein to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of the corresponding embodiments.

[0035]In describing of the drawings, similar reference numerals may be used for similar or related elements.

[0036]The singular form of a noun corresponding to an item may include one or more of the items unless clearly indicated otherwise in a related context.

[0037]In the disclosure, phrases, such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one or all possible combinations of the items listed together in the corresponding phrase among the phrases.

[0038]As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0039]Terms such as “1st”, “2nd”,...

Claims

1. A refrigerator comprising:a storage compartment;an evaporator;a defrost heater provided around the evaporator;a compressor configured to compress a refrigerant discharged from the evaporator;a fan configured to supply air cooled by the evaporator to the storage compartment;at least one memory storing instructions and configured to record temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals; andat least one processor,wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to:identify an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point;identify whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; andoperate the defrost heater based on identifying that the defrost condition is satisfied.

2. The refrigerator of claim 1, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to:identify a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point;identify a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; andidentify the index value based on the difference value between the first value and the second value.

3. The refrigerator of claim 1, wherein the second time point is a past time point that satisfies a defined condition among time points before the first time point, andwherein the defined condition includes operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

4. The refrigerator of claim 3, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to, based on a presence of a plurality of past time points that satisfy the defined condition, identify an oldest time point among the plurality of past time points as the second time point.

5. The refrigerator of claim 3, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to, based on an absence of a past time point that satisfies the defined condition, omit identifying the index value corresponding to the first time point.

6. The refrigerator of claim 1, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to delete oldest recorded information among the information recorded at the defined time intervals, based on a number of pieces of information recorded at the defined time intervals exceeding a defined number.

7. The refrigerator of claim 1, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to identify the index value at the defined time intervals, based on an elapse of a preset time from at least one of a time point at which an operation of the defrost heater ends or a time point at which power is applied to the refrigerator.

8. The refrigerator of claim 1, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, a rotation speed of the fan being greater than a defined threshold rotation speed, and the index value corresponding to the first time point being greater than a threshold value.

9. The refrigerator of claim 1, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to identify that the defrost condition is satisfied, based on the compressor being in operation for a preset time, and a defined number of consecutive index values identified at the defined time intervals all being greater than a threshold value.

10. The refrigerator of claim 1, wherein the instructions, when executed by the at least one processor individually or collectively, cause the refrigerator to operate the defrost heater based on a cumulative operation time of the compressor exceeding a preset time, based on identifying that the defrost condition is not satisfied.

11. A method for controlling a refrigerator comprising a storage compartment, an evaporator, a defrost heater provided around the evaporator, a compressor configured to compress a refrigerant discharged from the evaporator; and a fan configured to supply air cooled by the evaporator to the storage compartment, the method comprising:recording temperature information of the storage compartment, temperature information of the evaporator, operation information of the compressor, and operation information of the fan at defined time intervals;identifying an index value for detecting a defrost condition based on the temperature information of the storage compartment and the temperature information of the evaporator recorded at a first time point, and the temperature information of the storage compartment and the temperature information of the evaporator recorded at a second time point;identifying whether the defrost condition is satisfied based on the index value, the operation information of the compressor, and the operation information of the fan; andoperating the defrost heater based on identifying that the defrost condition is satisfied.

12. The method of claim 11, wherein the identifying of the index value comprises:identifying a first value by assigning a defined first weight to a difference value between a temperature value of the evaporator and a temperature value of the storage compartment recorded at the first time point;identifying a second value by assigning a defined second weight to the difference value between the temperature value of the evaporator and the temperature value of the storage compartment recorded at the second time point; andidentifying the index value based on the difference value between the first value and the second value.

13. The method of claim 11, wherein the second time point is a past time point that satisfies a defined condition among time points before the first time point, andwherein the defined condition includes operation information of the compressor and operation information of the fan recorded at the past time point being identical to operation information of the compressor and operation information of the fan recorded at the first time point.

14. The method of claim 13, further comprising:based on a presence of a plurality of past time points that satisfy the defined condition, identifying an oldest time point among the plurality of past time points as the second time point.

15. The method of claim 13, further comprising:based on an absence of a past time point that satisfies the defined condition, omitting the identifying of the index value corresponding to the first time point.

Images