Refrigerator and defrosting control method thereof

Abstract

According to the refrigerator and the defrosting control method thereof, a frost blockage prevention control program is added to the refrigerator, and whether an evaporator is subjected to frost blockage or not is judged by collecting the change condition of the temperature of a storage chamber within a certain time after a door is opened and closed, so that a defrosting heater is indicated to perform forced defrosting, and poor refrigeration of the refrigerator is prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerators, and in particular to a refrigerator and a defrosting control method thereof. Background Art

[0002] After the refrigerator is frequently opened and closed, a large amount of outside air enters the box. The new air is circulated through the wind circulation system and reaches the fin evaporator through the return air duct. A large amount of water vapor will condense on the evaporator, causing frost blockage. The cold air cannot be blown from the evaporator to the compartment, causing the compartment temperature to continue to rise. This is especially serious in high temperature and high humidity environments. There are two main ways to control the conventional evaporator defrosting. One is regular defrosting, where the refrigerator defrosts once every set time; the other is cumulative defrosting, which calculates the cumulative running time of the compressor plus the door opening time multiplied by the conversion coefficient to obtain a total defrosting count value, which is then compared with the preset value. The refrigerator will only defrost when the preset value is reached. The above two defrosting methods will cause frost blockage on the evaporator when the refrigerator door is frequently opened and closed, and defrosting cannot be performed in time. Summary of the invention

[0003] The purpose of the embodiment of the present invention is to provide a refrigerator and a defrosting control method thereof, which can accurately determine whether frost blockage occurs in the evaporator, thereby defrosting in time and preventing poor refrigeration in the refrigerator.

[0004] To achieve the above object, an embodiment of the present invention provides a refrigerator, comprising:

[0005] a box body, in which at least one storage chamber is formed, and the storage chamber includes at least a refrigerating chamber and a freezing chamber;

[0006] A door, used for opening and closing the storage room;

[0007] A refrigeration system is arranged in the box body and is used to provide cold air to the storage room. The refrigeration system includes a compressor, a condenser and an evaporator. The compressor, the condenser and the evaporator form a refrigerant circuit through pipelines.

[0008] A compartment temperature sensor is provided in the storage compartment and is used to detect the real-time compartment temperature of the storage compartment;

[0009] The controller is configured as:

[0010] When it is detected that the door of the target storage room is switched from an open state to a closed state, the operating state of the compressor is determined;

[0011] When the compressor is in the on state, obtaining the real-time room temperature detected by the room temperature sensor;

[0012] When the temperature difference between the real-time room temperature and the startup temperature is greater than or equal to a preset difference threshold, the real-time room temperature is continuously recorded n times within a preset frost blockage determination time, and the whole machine operation time of the refrigerator is obtained; wherein n≥2, and n is an integer;

[0013] If the real-time room temperature recorded n times has no downward trend, and the whole machine operation time is greater than the preset operation time threshold, the defrost mode is entered.

[0014] As an improvement of the above scheme, the compartment temperature sensor includes a refrigeration temperature sensor for obtaining the real-time refrigeration temperature and a freezing temperature sensor for obtaining the real-time freezing temperature; then, when the target storage room is a refrigeration room, the real-time room temperature is the real-time refrigeration temperature, the power-on temperature is the refrigeration power-on temperature, and the difference threshold is the refrigeration difference threshold; when the target storage room is a freezing room, the real-time room temperature is the real-time freezing temperature, the power-on temperature is the freezing power-on temperature, and the difference threshold is the freezing difference threshold.

[0015] As an improvement of the above solution, the refrigerator further includes:

[0016] An ambient temperature sensor is disposed outside the box and is used to detect the ambient temperature of the environment in which the refrigerator is located;

[0017] An environmental humidity sensor is arranged outside the box and is used to detect the environmental humidity of the environment in which the refrigerator is located;

[0018] Then, the controller is further configured to:

[0019] Acquiring the ambient temperature detected by the ambient temperature sensor and acquiring the ambient humidity detected by the ambient humidity sensor;

[0020] Calculate the cumulative door opening time when the door of the target storage room is switched from an open state to a closed state;

[0021] The corresponding frost blockage determination time is determined according to the ambient temperature, the ambient humidity and the accumulated door opening time.

[0022] As an improvement of the above solution, the ambient temperature is positively correlated with the frost blockage determination time, the ambient humidity is positively correlated with the frost blockage determination time, and the accumulated door opening time is positively correlated with the frost blockage determination time.

[0023] As an improvement of the above solution, the controller is further configured as follows:

[0024] When the compressor is in a stopped state, the compressor is waited to be started.

[0025] As an improvement of the above solution, after detecting that the door of the target storage room is switched from an open state to a closed state, the controller is further configured to:

[0026] Obtaining the number of times the door of the target storage room is opened within a set time period;

[0027] When the door opening times are greater than or equal to a preset times threshold, the operating state of the compressor is determined.

[0028] To achieve the above object, an embodiment of the present invention further provides a refrigerator defrosting control method, comprising:

[0029] When detecting that a door of a target storage compartment in the refrigerator is switched from an open state to a closed state, determining an operating state of a compressor in the refrigerator;

[0030] When the compressor is in the on state, obtaining the real-time room temperature of the target storage room;

[0031] When the temperature difference between the real-time room temperature and the startup temperature is greater than or equal to a preset difference threshold, the real-time room temperature is continuously recorded n times within a preset frost blockage determination time, and the whole machine operation time of the refrigerator is obtained; wherein n≥2, and n is an integer;

[0032] If the real-time room temperature recorded n times has no downward trend, and the whole machine operation time is greater than the preset operation time threshold, the refrigerator is controlled to enter the defrost mode.

[0033] As an improvement of the above scheme, when the target storage room is a refrigerator room, the real-time room temperature is the real-time refrigeration temperature, the power-on temperature is the refrigeration power-on temperature, and the difference threshold is the refrigeration difference threshold; when the target storage room is a freezer room, the real-time room temperature is the real-time freezing temperature, the power-on temperature is the freezing power-on temperature, and the difference threshold is the freezing difference threshold.

[0034] As an improvement of the above solution, the method further includes:

[0035] Obtain the ambient temperature and ambient humidity of the environment where the refrigerator is located;

[0036] Calculate the cumulative door opening time when the door of the target storage room is switched from an open state to a closed state;

[0037] The corresponding frost blockage determination time is determined according to the ambient temperature, the ambient humidity and the accumulated door opening time.

[0038] As an improvement of the above solution, the ambient temperature is positively correlated with the frost blockage determination time, the ambient humidity is positively correlated with the frost blockage determination time, and the accumulated door opening time is positively correlated with the frost blockage determination time.

[0039] As an improvement of the above solution, the method further includes:

[0040] When the compressor is in a stopped state, the compressor is waited to be started.

[0041] The refrigerator and defrost control method thereof disclosed in the present invention add a frost prevention control program to the refrigerator, and judge whether frost blockage occurs on the evaporator by collecting the change of storage chamber temperature within a certain period of time after the door is opened and closed, thereby instructing the defrost heater to perform forced defrosting to prevent poor refrigeration of the refrigerator. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a schematic diagram of the external structure of a refrigerator provided by an embodiment of the present invention;

[0043] Figure 2 is a schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention;

[0044] Figure 3 is another schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention;

[0045] Figure 4 is a schematic structural diagram of a refrigeration system in a refrigerator provided by an embodiment of the present invention;

[0046] Figure 5 is a schematic diagram of the connection between the controller and other hardware devices provided by an embodiment of the present invention;

[0047] Figure 6 is a first working flow diagram of a controller provided by an embodiment of the present invention;

[0048] Figure 7 is a second working flow diagram of the controller provided by an embodiment of the present invention;

[0049] Figure 8 is a third working flow diagram of the controller provided in an embodiment of the present invention;

[0050] Fig. 9 is a fourth working flow diagram of the controller provided by an embodiment of the present invention;

[0051] Fig.10 The present invention is a flowchart of a refrigerator defrosting control method provided by an embodiment of the present invention.

[0052] Among them, 100, refrigerator; 1, compressor; 2, evaporator; 3, capillary; 4, condenser; 5, defrost heater; 11, freezer; 12, refrigerator; 111, freezing temperature sensor; 112, refrigerator temperature sensor; 113, ambient temperature sensor; 114, ambient humidity sensor; 121, refrigerator temperature adjustment potentiometer. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0055] The terms "first", "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0056] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] See also Figure 1 , Figure 1It is a schematic diagram of the external structure of a refrigerator 100 provided in an embodiment of the present invention. The refrigerator described in the embodiment of the present invention is an air-cooled refrigerator. The refrigerator 100 described in the embodiment of the present invention is approximately in the shape of a rectangular parallelepiped. The refrigerator includes a box body that defines a storage space and a plurality of door bodies arranged at the opening of the box body, wherein the door body includes a door body shell located on the outside of the box body, a door body liner located on the inside of the box body, an upper end cover, a lower end cover, and an insulating layer located between the door body shell, the door body liner, the upper end cover, and the lower end cover; usually, the insulating layer is filled with foam material. The box body is provided with a chamber, wherein the chamber includes a component storage chamber for placing components in the refrigerator, such as a press cabin, etc., and also includes a storage space for storing food, etc. A display screen is provided at the door of the refrigerator, and the display screen is used to display prompt information and receive user touch operations.

[0058] See also Figure 2 , Figure 2 1 is a schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention. The storage space can be divided into multiple storage rooms. The storage rooms can be configured as a freezer 11 and a refrigerator 12 according to different uses. They can also include a variable temperature room, a vacuum drawer, a moisturizing drawer, etc. In the refrigerator 100 shown in the embodiment of the present invention, the freezer 11 is located above the refrigerator 12. In other embodiments, the freezer 11 can also be located below the refrigerator 12. Each storage room corresponds to one or more door bodies, for example, Figure 2 In the freezer compartment 11 at the top, a double-door body is provided. The door body can be pivotally arranged at the opening of the box body, and can also be opened in a drawer-like manner to realize drawer-like storage.

[0059] See also Figure 3 , Figure 3 1 is another schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention, wherein a freezing temperature sensor 111 is provided inside the freezing chamber 11, and the freezing temperature sensor is used to obtain the real-time freezing temperature of the freezing chamber 11, and a refrigerating temperature sensor 112 is provided inside the refrigerating chamber 12, and the freezing temperature sensor is used to obtain the real-time freezing temperature of the freezing chamber 11. The refrigerating chamber 12 is also provided with a refrigerating temperature adjustment potentiometer 121, and the refrigerating temperature adjustment potentiometer 121 is used to adjust the temperature level of the refrigerating chamber 12. Furthermore, an ambient temperature sensor 113 and an ambient humidity sensor 114 are also provided outside the body of the refrigerator 100, and the ambient temperature sensor 113 is used to detect the ambient temperature of the environment in which the refrigerator is located, and the ambient humidity sensor 114 is used to detect the ambient humidity of the environment in which the refrigerator is located.

[0060] See also Figure 4 , Figure 4The schematic diagram of the structure of the refrigeration system in the refrigerator provided by the embodiment of the present invention, the refrigeration system includes a compressor 1, an evaporator 2, a drying filter (not shown in the figure), a capillary tube 3, a condenser 4 and a gas-liquid separator (not shown in the figure). The working process of the refrigeration system includes a compression process, a condensation process, a throttling process and an evaporation process. The compression process is: plug in the power cord of the refrigerator, when the contacts of the thermostat are connected, the compressor 1 starts to work, and the low-temperature and low-pressure refrigerant is sucked into the compressor 1, and is compressed into a high-temperature and high-pressure superheated gas in the cylinder of the compressor 1 and then discharged into the condenser 4; the condensation process is: the high-temperature and high-pressure refrigerant gas dissipates heat through the condenser 4, the temperature continues to drop, and is gradually cooled to a saturated vapor of normal temperature and high pressure, and is further cooled to a saturated liquid, and the temperature no longer drops. The temperature at this time is called the condensation temperature, and the pressure of the refrigerant remains almost unchanged during the entire condensation process; the throttling process is as follows ... The process is as follows: the condensed refrigerant saturated liquid is filtered through a drying filter to remove moisture and impurities and then flows into the capillary 3, through which it is throttled and depressurized, and the refrigerant becomes wet steam at room temperature and low pressure; the evaporation process is as follows: the wet steam at room temperature and low pressure begins to absorb heat and vaporize in the evaporator 2, which not only reduces the temperature of the evaporator 2 and its surroundings, but also turns the refrigerant into a low-temperature, low-pressure gas. The refrigerant coming out of the evaporator 2 passes through the gas-liquid separator and returns to the compressor 1 again, repeating the above process to transfer the heat in the refrigerator to the air outside the box, thereby achieving the purpose of refrigeration.

[0061] See also Figure 5 , Figure 5 1 is a connection diagram of the controller provided in the embodiment of the present invention and other hardware devices, and the detection values ​​of the freezing temperature sensor 111, the refrigeration temperature sensor 112, the ambient temperature sensor 113 and the ambient humidity sensor 114 are obtained through the controller in the refrigerator. Furthermore, the refrigerator described in the embodiment of the present invention also includes a defrost heater 5. The frost-free refrigerator is equipped with a defrost heater 5 at the lower end of the finned evaporator 2. The defrost heater 5 and the defrost timer and the bimetallic thermostat and the temperature fuse (when the temperature exceeds the set value, the temperature fuse melts and cuts off the power supply of the electric heating tube) form an automatic defrosting system. When the compressor works for a period of time, the surface of the evaporator 2 will frost. If defrosting is not performed, the frost will become thicker and thicker, and then the evaporator will be filled with frost and the air duct will be blocked, forming frost blockage, so that the cold air cannot circulate and the refrigeration effect is reduced. After the controller controls the defrost timer to work for a period of time, it automatically cuts off the power supply of the compressor and turns on the defrost heater 5. The defrost heater 5 heats to melt the frost on the evaporator 2. When the temperature rises to a certain temperature, the bimetallic thermostat disconnects and cuts off the power supply of the defrost heater 5. After the defrost is completed, the defrost timer cuts off the power supply of the defrost heater 5, turns on the power supply of the compressor to resume refrigeration, and the cycle repeats itself.

[0062] Specifically, the controller is configured to: determine the operating state of the compressor when detecting that the door of the target storage room switches from an open state to a closed state; when the compressor is in the on state, obtain the real-time room temperature detected by the compartment temperature sensor; when the temperature difference between the real-time room temperature and the on-state temperature is greater than or equal to a preset difference threshold, continuously record the real-time room temperature n times within a preset frost blockage determination time, and obtain the whole machine running time of the refrigerator; wherein n ≥ 2, and n is an integer; if the real-time room temperature recorded n times has no downward trend, and the whole machine running time is greater than the preset running time threshold, enter the defrost mode. When the compressor is in the off state, wait for the compressor to be turned on.

[0063] For example, see Figure 6 , Figure 6 It is a first working flow chart of the controller provided in an embodiment of the present invention, and the controller is configured to execute steps S101 to S111.

[0064] Specifically, in steps S101 to S104, after the air-cooled refrigerator performs frequent door opening and closing actions, a large amount of outside air enters the refrigerator, and the new air reaches the fin evaporator through the return air duct along the air circulation system. A large amount of water vapor will condense on the evaporator to cause frost blockage. Therefore, in the embodiment of the present invention, it is first determined whether the door of the target storage room has experienced the "open door-close door" stage. If so, when it is detected that the door of the target storage room is closed, the operating status of the compressor is determined. Since the compressor may be in a stopped state, it is necessary to wait for the compressor to start up.

[0065] Furthermore, in step S101, in order to enhance the accuracy of judging frost blockage and further detect whether the frequent door opening condition is met, after detecting that the door of the target storage room switches from an open state to a closed state, the controller is also configured to: obtain the number of door openings m of the target storage room within a set time period; when the number of door openings m is greater than or equal to a preset number threshold, determine the operating status of the compressor.

[0066] Exemplarily, if the number threshold is 2 or other values, then within the set time period (such as 1 hour), it is detected whether the door of the target storage room has gone through m "open door-close door" stages, m≥2, and m is an integer.

[0067] Specifically, in steps S105 to S107, when the compressor is in the on state, the real-time room temperature detected by the compartment temperature sensor is obtained. When the real-time room temperature is greater than the preset on-state temperature, it is determined whether the temperature difference between the real-time room temperature and the on-state temperature is greater than or equal to the preset difference threshold, that is, whether it satisfies: real-time room temperature ≥ on-state temperature + difference threshold; if it satisfies, it means that the room temperature of the storage room is too high at this time, and there may be frost blocking. At this time, the real-time room temperature is continuously recorded n times every t minutes within the preset frost blocking determination time, and the whole machine operation time of the refrigerator is obtained. It is necessary to further determine whether frost blocking occurs in combination with these parameters; if it does not satisfy, it means that the room temperature of the storage room is moderate at this time, and there is no frost blocking phenomenon. Exemplarily, the difference threshold can be set according to the empirical value, such as 3°C, 4°C, etc., and the present invention does not make specific limitations on this; the values ​​of t and n are determined by the frost blocking determination time, and the frost blocking determination time = t * n.

[0068] Specifically, in steps S108 to S111, after the real-time room temperature is recorded n times continuously within the preset frost blockage determination time and the whole machine operation time of the refrigerator is obtained, when the real-time room temperature recorded n times continuously shows no downward trend, it means that the temperature of the target storage room is too high for a long time, which is largely caused by insufficient cold air. At this time, it is further determined whether the whole machine operation time of the refrigerator is greater than the operation time threshold. If so, it means that the compressor has been running for a long time, the interval from the last defrosting is long, and the frosting is serious. It can be determined that the evaporator is frost blocked and needs to enter the defrost mode immediately; if not, it means that the compressor has been running for a short time, which may be because the room temperature has not been able to drop to a low temperature after the last defrosting. At this time, the refrigerator is controlled to continue to operate in the refrigeration mode. In this case, the speed of the compressor can be appropriately increased to ensure that the temperature of the target storage room will not be high for a long time. Exemplarily, the operation time threshold can be set according to an empirical value, such as 7h, 8h, etc., and the present invention does not make specific limitations on this.

[0069] In an embodiment of the present invention, an anti-frost control program is added to the refrigerator. By collecting the changes in the storage chamber temperature within a certain period of time after opening and closing the door, it is determined whether the evaporator is blocked by frost, thereby instructing the defrost heater to perform forced defrosting to prevent poor refrigeration of the refrigerator.

[0070] Specifically, the controller is further configured to: obtain the ambient temperature detected by the ambient temperature sensor and the ambient humidity detected by the ambient humidity sensor; calculate the cumulative door opening time when the door of the target storage room is switched from an open state to a closed state; and determine the corresponding frost blockage determination time according to the ambient temperature, the ambient humidity and the cumulative door opening time. The ambient humidity is positively correlated with the frost blockage determination time, and the cumulative door opening time is positively correlated with the frost blockage determination time.

[0071] For example, see Figure 7 , Figure 7 It is the second working flow chart of the controller provided by an embodiment of the present invention. After executing step S101, the controller is further configured to execute steps S121 to S123. The defrost determination time can be dynamically adjusted, which is mainly determined by the current (most recent) cumulative door opening time, ambient temperature and ambient humidity. When the collected door opening time is higher than the cumulative door opening time, ambient temperature or ambient humidity, the corresponding frost blockage determination time is longer, otherwise the corresponding frost blockage determination time is shorter.

[0072] In the first embodiment, the controller's memory pre-stores the correspondence between the frost blockage determination time and the cumulative door opening time (range value), ambient temperature (range value), and ambient humidity (range value), which can be stored in a data table. When the cumulative door opening time, ambient temperature, and ambient humidity are detected in real time, the corresponding frost blockage determination time is obtained by a table lookup method.

[0073] In a second embodiment, the controller's memory pre-stores the corresponding relationship between the standard frost blockage determination time and the standard door opening cumulative time, standard ambient temperature, and standard ambient humidity. At this time, after the door opening cumulative time, ambient temperature, and ambient humidity are detected in real time, the standard frost blockage determination time is adjusted by one-to-one comparison to obtain the actual frost blockage determination time. For example, if the door opening cumulative time detected in real time is compared with the standard door opening cumulative time, if it is greater than, the standard frost blockage determination time is extended; if it is equal, the standard frost blockage determination time is kept unchanged; if it is less than, the standard frost blockage determination time is shortened. The specific extension and shortening adjustment amount can be pre-set according to the empirical value. Similarly, the same adjustment method is used for the ambient temperature and ambient humidity detected in real time.

[0074] Specifically, the compartment temperature sensor includes a refrigeration temperature sensor for obtaining the real-time refrigeration temperature and a freezing temperature sensor for obtaining the real-time freezing temperature; then, when the target storage compartment is a refrigeration compartment, the real-time compartment temperature is the real-time refrigeration temperature, the startup temperature is the refrigeration startup temperature, and the difference threshold is the refrigeration difference threshold; when the target storage compartment is a freezing compartment, the real-time compartment temperature is the real-time freezing temperature, the startup temperature is the freezing startup temperature, and the difference threshold is the freezing difference threshold. The freezing difference threshold and the refrigeration difference threshold may be equal or unequal.

[0075] Exemplarily, when the target storage room is the cold storage room, see Figure 8 , Figure 8 This is the third working flow diagram of the controller provided by the embodiment of the present invention. After detecting that the refrigerator performs an "open door-close door" action in the refrigeration chamber, it first determines whether the compressor is in operation. If so, it determines whether the real-time refrigeration temperature Tr exceeds the refrigeration startup temperature Trk + refrigeration difference threshold Tn1; if not, it waits for the compressor to start up, and then determines whether the real-time refrigeration temperature Tr exceeds the refrigeration startup temperature Trk + Tn1. If the real-time refrigeration temperature Tr exceeds the refrigeration startup temperature Trk + Tn1, the real-time refrigeration temperature Tr is recorded every 5 minutes, and recorded continuously for n times. If the real-time refrigeration temperature Tr recorded for n times does not drop, and the whole machine is running for more than 8 hours (that is, more than 8 hours since the last defrosting), it is determined to be frost blockage, and the refrigerator is forced to defrost.

[0076] Exemplarily, when the target storage compartment is the freezer compartment, see Fig. 9 , Fig. 9 This is the fourth work flow chart of the controller provided by the embodiment of the present invention. After detecting that the refrigerator performs an "open door-close door" action in the freezer compartment, it first determines whether the compressor is in operation. If so, it determines whether the real-time freezing temperature Tf exceeds the freezing start-up temperature Tfk + freezing difference threshold Tn2; if not, it waits for the compressor to start up, and then determines whether the real-time freezing temperature Tf exceeds the freezing start-up temperature Tfk + Tn2. If the real-time freezing temperature Tf exceeds the freezing start-up temperature Tfk + Tn2, the real-time freezing temperature Tf is recorded every 5 minutes, and recorded continuously for n times. If the real-time freezing temperature Tf recorded for n times does not drop, and the whole machine is running for more than 8 hours (that is, more than 8 hours since the last defrosting), it is determined to be frost blockage, and the refrigerator is forced to defrost.

[0077] The refrigerator and defrost control method thereof disclosed in the present invention add a frost prevention control program to the refrigerator, and judge whether frost blockage occurs on the evaporator by collecting the change of storage chamber temperature within a certain period of time after the door is opened and closed, thereby instructing the defrost heater to perform forced defrosting to prevent poor refrigeration of the refrigerator.

[0078] See also Fig.10 , Fig.10 : is a flowchart of a refrigerator defrost control method provided by an embodiment of the present invention. The refrigerator defrost control method is implemented by a controller in a refrigerator. The refrigerator defrost control method includes:

[0079] S1, when it is detected that the door of the target storage room in the refrigerator is switched from an open state to a closed state, determining the operating state of the compressor in the refrigerator;

[0080] S2. when the compressor is in the on state, obtaining the real-time room temperature of the target storage room;

[0081] S3. When the temperature difference between the real-time room temperature and the startup temperature is greater than or equal to a preset difference threshold, the real-time room temperature is continuously recorded n times within a preset frost blockage determination time, and the whole machine operation time of the refrigerator is obtained; wherein n≥2, and n is an integer;

[0082] S4. If the real-time room temperature recorded n times has no downward trend, and the whole machine operation time is greater than a preset operation time threshold, control the refrigerator to enter the defrost mode.

[0083] Furthermore, the method further comprises: when the compressor is in a stopped state, waiting for the compressor to be started.

[0084] For example, after the air-cooled refrigerator is frequently opened and closed, a large amount of outside air enters the refrigerator, and the new air follows the air circulation system through the return air duct to the fin evaporator. A large amount of water vapor will condense on the evaporator to cause frost blockage. Therefore, in the embodiment of the present invention, it is first determined whether the door of the target storage room has experienced the "open door-close door" stage. If so, when it is detected that the door of the target storage room is closed, the operating status of the compressor is determined. Since the compressor may be in a stopped state, it is necessary to wait for the compressor to start up.

[0085] Furthermore, in step S1, in order to enhance the accuracy of judging frost blockage and further detect whether the frequent door opening condition is met, after detecting that the door of the target storage room switches from an open state to a closed state, the method further includes: obtaining the number of door openings m of the target storage room within a set time period; when the number of door openings m is greater than or equal to a preset number threshold, determining the operating status of the compressor.

[0086] Exemplarily, if the number threshold is 2 or other values, then within the set time period (such as 1 hour), it is detected whether the door of the target storage room has gone through m "open door-close door" stages, m≥2, and m is an integer.

[0087] Exemplarily, when the compressor is in the on state, the real-time room temperature is obtained. When the real-time room temperature is greater than the preset on-temperature, it is determined whether the temperature difference between the real-time room temperature and the on-temperature is greater than or equal to the preset difference threshold, that is, whether it satisfies: real-time room temperature ≥ on-temperature + difference threshold; if it satisfies, it means that the room temperature of the storage room is too high at this time, and there may be frost blocking. At this time, the real-time room temperature is continuously recorded n times every t minutes within the preset frost blocking judgment time, and the whole machine operation time of the refrigerator is obtained. It is necessary to further determine whether frost blocking occurs in combination with these parameters; if it does not satisfy, it means that the room temperature of the storage room is moderate at this time, and there is no frost blocking phenomenon. Exemplarily, the difference threshold can be set according to the empirical value, such as 3°C, 4°C, etc., and the present invention does not make specific limitations on this; the values ​​of t and n are determined by the frost blocking judgment time, and the frost blocking judgment time = t * n.

[0088] Exemplarily, after the real-time room temperature is recorded n times continuously within the preset frost blockage determination time and the whole machine operation time of the refrigerator is obtained, when the real-time room temperature recorded n times continuously shows no downward trend, it means that the temperature of the target storage room is too high for a long time, which is largely caused by insufficient cold air. At this time, it is further determined whether the whole machine operation time of the refrigerator is greater than the operation time threshold. If so, it means that the compressor has been running for a long time, the interval from the last defrosting is long, and the frosting is serious. It can be determined that the evaporator is frost blocked and needs to enter the defrost mode immediately; if not, it means that the compressor has been running for a short time, which may be because the room temperature has not been able to drop to a low temperature after the last defrosting. At this time, the refrigerator is controlled to continue to operate in the refrigeration mode. In this case, the speed of the compressor can be appropriately increased to ensure that the temperature of the target storage room will not be high for a long time. Exemplarily, the operation time threshold can be set according to an empirical value, such as 7h, 8h, etc., and the present invention does not make specific limitations on this.

[0089] Specifically, the method further includes: obtaining the ambient temperature and ambient humidity of the environment in which the refrigerator is located; calculating the cumulative door opening time when the door of the target storage room is switched from an open state to a closed state; and determining the corresponding frost blockage determination time according to the ambient temperature, the ambient humidity and the cumulative door opening time. The ambient temperature is positively correlated with the frost blockage determination time, the ambient humidity is positively correlated with the frost blockage determination time, and the cumulative door opening time is positively correlated with the frost blockage determination time.

[0090] Exemplarily, the defrost determination time can be dynamically adjusted, mainly determined by the current (most recent) cumulative door opening time, ambient temperature and ambient humidity. When the collected door opening time is higher than the cumulative door opening time, ambient temperature or ambient humidity, the corresponding frost blockage determination time is longer, otherwise the corresponding frost blockage determination time is shorter.

[0091] In the first embodiment, the controller's memory pre-stores the correspondence between the frost blockage determination time and the cumulative door opening time (range value), ambient temperature (range value), and ambient humidity (range value), which can be stored in a data table. When the cumulative door opening time, ambient temperature, and ambient humidity are detected in real time, the corresponding frost blockage determination time is obtained by a table lookup method.

[0092] In a second embodiment, the controller's memory pre-stores the corresponding relationship between the standard frost blockage determination time and the standard door opening cumulative time, standard ambient temperature, and standard ambient humidity. At this time, after the door opening cumulative time, ambient temperature, and ambient humidity are detected in real time, the standard frost blockage determination time is adjusted by one-to-one comparison to obtain the actual frost blockage determination time. For example, if the door opening cumulative time detected in real time is compared with the standard door opening cumulative time, if it is greater than, the standard frost blockage determination time is extended; if it is equal, the standard frost blockage determination time is kept unchanged; if it is less than, the standard frost blockage determination time is shortened. The specific extension and shortening adjustment amount can be pre-set according to the empirical value. Similarly, the same adjustment method is used for the ambient temperature and ambient humidity detected in real time.

[0093] Specifically, when the target storage room is a refrigerator, the real-time room temperature is the real-time refrigerator temperature, the startup temperature is the refrigerator startup temperature, and the difference threshold is the refrigerator difference threshold; when the target storage room is a freezer, the real-time room temperature is the real-time freezer temperature, the startup temperature is the freezer startup temperature, and the difference threshold is the freezer difference threshold. The freezer difference threshold and the refrigerator difference threshold may be equal or unequal.

[0094] For example, after detecting that the refrigerator performs an "open-close" action of the refrigerator compartment, first determine whether the compressor is in operation. If so, determine whether the real-time refrigeration temperature Tr exceeds the refrigeration startup temperature Trk + refrigeration difference threshold Tn1; if not, wait until the compressor is turned on, and then determine whether the real-time refrigeration temperature Tr exceeds the refrigeration startup temperature Trk + Tn1. If the real-time refrigeration temperature Tr exceeds the refrigeration startup temperature Trk + Tn1, the real-time refrigeration temperature Tr is recorded every 5 minutes, and recorded n times continuously. If the real-time refrigeration temperature Tr recorded n times does not drop, and the whole machine has been running for more than 8 hours (that is, more than 8 hours since the last defrosting), it is determined to be frost blockage, and the refrigerator is forced to defrost.

[0095] For example, after detecting that the refrigerator performs an "open-close" action of the freezer compartment, first determine whether the compressor is in operation. If so, determine whether the real-time freezing temperature Tf exceeds the freezing start-up temperature Tfk + freezing difference threshold Tn2; if not, wait until the compressor is turned on, and then determine whether the real-time freezing temperature Tf exceeds the freezing start-up temperature Tfk + Tn2. If the real-time freezing temperature Tf exceeds the freezing start-up temperature Tfk + Tn2, then record the real-time freezing temperature Tf every 5 minutes, and record it continuously for n times. If the real-time freezing temperature Tf recorded for n times does not drop, and the whole machine is running for more than 8 hours (that is, more than 8 hours since the last defrosting), it is determined to be frost blockage, and the refrigerator is forced to defrost.

[0096] The refrigerator and defrost control method thereof disclosed in the present invention add a frost prevention control program to the refrigerator, and judge whether frost blockage occurs on the evaporator by collecting the change of storage chamber temperature within a certain period of time after the door is opened and closed, thereby instructing the defrost heater to perform forced defrosting to prevent poor refrigeration of the refrigerator.

[0097] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A refrigerator, characterized in that: include: a box body, in which at least one storage chamber is formed, and the storage chamber includes at least a refrigerating chamber and a freezing chamber; A door, used for opening and closing the storage room; A refrigeration system is arranged in the box body and is used to provide cold air to the storage room. The refrigeration system includes a compressor, a condenser and an evaporator. The compressor, the condenser and the evaporator form a refrigerant circuit through pipelines. A compartment temperature sensor is provided in the storage compartment and is used to detect the real-time compartment temperature of the storage compartment; The controller is configured as: When it is detected that the door of the target storage room is switched from an open state to a closed state, the operating state of the compressor is determined; When the compressor is in the on state, obtaining the real-time room temperature detected by the room temperature sensor; When the temperature difference between the real-time room temperature and the startup temperature is greater than or equal to a preset difference threshold, the real-time room temperature is continuously recorded n times within a preset frost blockage determination time, and the whole machine operation time of the refrigerator is obtained; wherein n≥2, and n is an integer; If the real-time room temperature recorded n times has no downward trend, and the whole machine operation time is greater than the preset operation time threshold, the defrost mode is entered.

2. The refrigerator according to claim 1, characterized in that: The compartment temperature sensor includes a refrigeration temperature sensor for obtaining a real-time refrigeration temperature and a freezing temperature sensor for obtaining a real-time freezing temperature; then, when the target storage compartment is a refrigeration compartment, the real-time compartment temperature is the real-time refrigeration temperature, the power-on temperature is the refrigeration power-on temperature, and the difference threshold is the refrigeration difference threshold; when the target storage compartment is a freezing compartment, the real-time compartment temperature is the real-time freezing temperature, the power-on temperature is the freezing power-on temperature, and the difference threshold is the freezing difference threshold.

3. The refrigerator according to claim 1, characterized in that: The refrigerator further comprises: An ambient temperature sensor is disposed outside the box and is used to detect the ambient temperature of the environment in which the refrigerator is located; An environmental humidity sensor is arranged outside the box and is used to detect the environmental humidity of the environment in which the refrigerator is located; Then, the controller is further configured to: Acquire the ambient temperature detected by the ambient temperature sensor and acquire the ambient humidity detected by the ambient humidity sensor; Calculate the cumulative door opening time when the door of the target storage room is switched from an open state to a closed state; The corresponding frost blockage determination time is determined according to the ambient temperature, the ambient humidity and the accumulated door opening time.

4. The refrigerator according to claim 3, characterized in that: The ambient temperature is positively correlated with the frost blockage determination time, the ambient humidity is positively correlated with the frost blockage determination time, and the accumulated door opening time is positively correlated with the frost blockage determination time.

5. The refrigerator according to claim 1, characterized in that: The controller is also configured to: When the compressor is in a stopped state, the compressor is waited to be started.

6. The refrigerator according to claim 1, characterized in that: After detecting that the door of the target storage room is switched from an open state to a closed state, the controller is further configured to: Obtaining the number of times the door of the target storage room is opened within a set time period; When the door opening times are greater than or equal to a preset times threshold, the operating state of the compressor is determined.

7. A refrigerator defrosting control method, characterized in that: include: When detecting that a door of a target storage compartment in the refrigerator is switched from an open state to a closed state, determining an operating state of a compressor in the refrigerator; When the compressor is in the on state, obtaining the real-time room temperature of the target storage room; When the temperature difference between the real-time room temperature and the startup temperature is greater than or equal to a preset difference threshold, the real-time room temperature is continuously recorded n times within a preset frost blockage determination time, and the whole machine operation time of the refrigerator is obtained; wherein n≥2, and n is an integer; If the real-time room temperature recorded n times has no downward trend, and the whole machine operation time is greater than the preset operation time threshold, the refrigerator is controlled to enter the defrost mode.

8. The refrigerator defrosting control method according to claim 7, characterized in that: When the target storage room is a refrigerator room, the real-time room temperature is the real-time refrigerator temperature, the power-on temperature is the refrigerator power-on temperature, and the difference threshold is the refrigerator difference threshold; when the target storage room is a freezer room, the real-time room temperature is the real-time freezer temperature, the power-on temperature is the freezer power-on temperature, and the difference threshold is the freezer difference threshold.

9. The refrigerator defrosting control method according to claim 7, characterized in that: The method further comprises: Obtain the ambient temperature and ambient humidity of the environment where the refrigerator is located; Calculate the cumulative door opening time when the door of the target storage room is switched from an open state to a closed state; The corresponding frost blockage determination time is determined according to the ambient temperature, the ambient humidity and the accumulated door opening time.

10. The refrigerator defrosting control method according to claim 7, characterized in that: The method further comprises: When the compressor is in a stopped state, the compressor is waited to be started.

Images