Refrigerator and control method thereof

Abstract

The application provides a refrigerator and a control method thereof, and belongs to the technical field of refrigerators. A first temperature sensor arranged at the top of a refrigeration cavity and a second temperature sensor arranged at the bottom of the refrigeration cavity are used to collect a first temperature and a second temperature respectively, then the first temperature is subtracted by a first preset temperature to obtain a first temperature difference, and the second temperature is subtracted by a second preset temperature to obtain a second temperature difference. According to the matching of the first temperature difference and the second temperature difference with the corresponding preset temperature fluctuation interval, the refrigeration state of the refrigerator is determined. This method can simultaneously obtain the temperature information of the upper and lower two regions of the refrigeration cavity, breaks through the defect of limited coverage of single-point temperature measurement, and can completely and truly feedback the overall temperature condition of the refrigeration cavity. Through the dual-temperature-difference joint determination method, the normal refrigeration condition and the abnormal refrigeration condition can be accurately distinguished, the determination logic is rigorous, the result is reliable, and the accuracy and reliability of the refrigeration state determination of the refrigerator can be improved.

Description

Technical Field

[0001] This application relates to the field of refrigerator technology, and mainly to a refrigerator and its control method. Background Technology

[0002] With economic development and the improvement of people's living standards, air-cooled refrigerators have been widely used in daily life, mainly relying on refrigeration and air supply systems to achieve low-temperature storage of food.

[0003] A typical air-cooled refrigerator consists of a cabinet and a door. The cabinet has an upper cavity and a lower cavity that are spaced apart. The door consists of an upper door and a lower door. The upper door is used to open and close the upper cavity, and the lower door is used to open and close the lower cavity.

[0004] Existing frost-free refrigerators typically only have a single temperature sensor in the refrigerator compartment. Judging the cooling status based on the temperature of a single point cannot comprehensively reflect the actual temperature distribution in the upper and lower areas of the refrigerator compartment. When problems such as poor airflow, frost buildup in the air ducts, or malfunction of the damper occur in a localized area of ​​the refrigerator compartment, the single-point temperature measurement method is difficult to identify the abnormal cooling status in a timely and accurate manner, which can easily lead to temperature judgment errors. Consequently, it is impossible to make effective adjustments in a timely manner, affecting the overall temperature control effect of the refrigerator compartment and the quality of food storage. Summary of the Invention

[0005] The main objective of this application is to provide a refrigerator and its control method, which aims to comprehensively determine the refrigeration condition by calculating the temperature difference at two temperature detection points at the top and bottom of the refrigeration cavity, thereby comprehensively and accurately identifying normal and abnormal refrigeration states and improving the accuracy and reliability of refrigerator refrigeration status determination.

[0006] To achieve the above objectives, a first aspect of this application provides a method for controlling a refrigerator, the refrigerator comprising:

[0007] The box contains a refrigeration chamber and a freezing chamber. A refrigeration system, comprising a compressor, a condenser, a capillary tube, and an evaporator connected in series to form a loop; An air supply system, comprising a fan, a main air supply duct, dampers, and a return air duct; The freezer chamber is equipped with an evaporator air duct compartment. The evaporator and the fan are both installed in the evaporator air duct compartment. The evaporator air duct compartment is provided with a communication port to communicate with the storage space of the freezer chamber. One end of the main air supply duct is connected to the evaporator air duct compartment, and the other end of the main air supply duct is connected to the top of the refrigerator compartment. The main air supply duct is used to transport the cold air generated by the evaporator to the refrigerator compartment. The damper is located inside the main air supply duct, and the damper is used to adjust the amount and direction of cold air flowing into the refrigeration chamber in the main air supply duct. One end of the return air duct is connected to the return air inlet at the bottom of the refrigeration chamber, and the other end of the return air duct flows back into the evaporator air duct compartment. The temperature detection assembly includes a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is disposed at the top of the refrigeration cavity and the second temperature sensor is disposed at the bottom of the refrigeration cavity; The control method includes: Acquire the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor; The first temperature difference is obtained by subtracting the first preset temperature from the first temperature, and the second temperature difference is obtained by subtracting the second preset temperature from the second temperature. When the first temperature difference is within the first preset temperature fluctuation range and the second temperature difference is within the second preset temperature fluctuation range, the cooling is determined to be normal. When the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, the refrigeration is determined to be abnormal.

[0008] The above technical solution has the following advantages or beneficial effects: In this embodiment, a first temperature sensor located at the top of the refrigerator cavity and a second temperature sensor located at the bottom of the refrigerator cavity collect first and second temperatures, respectively. The first temperature is then subtracted from a first preset temperature to obtain a first temperature difference, and the second temperature is subtracted from a second preset temperature to obtain a second temperature difference. Based on the matching of the first and second temperature differences with their corresponding preset temperature fluctuation ranges, the refrigerator's cooling status is determined. This method can simultaneously acquire temperature information from both the upper and lower areas of the refrigerator cavity, overcoming the limitation of limited coverage in single-point temperature measurement and providing a complete and accurate reflection of the overall temperature of the refrigerator cavity. By using a dual-temperature-difference joint determination method, normal and abnormal cooling conditions can be accurately distinguished. The determination logic is rigorous, and the results are reliable, providing solid data support for subsequent control operations such as damper adjustment, airflow control, and fault handling, thereby ensuring the stable operation of the refrigerator's cooling system and optimizing the overall temperature control performance of the refrigerator cavity.

[0009] In some embodiments of this application, after determining that the cooling is normal, the method further includes: The damper is opened or closed based on the first temperature collected by the first temperature sensor.

[0010] The above technical solution has the following advantages or beneficial effects: In this embodiment, under normal refrigeration conditions, the opening and closing of the damper is controlled based on the first temperature collected by the first temperature sensor. This allows for dynamic adjustment of the flow of cold air from the main air duct to the refrigeration chamber, in conjunction with the real-time temperature at the top of the refrigeration chamber. This control method precisely matches the actual refrigeration needs of the refrigeration chamber, rationally managing the timing and amount of cold air delivery, ensuring the refrigeration chamber temperature remains stable within the normal range. While guaranteeing the preservation effect of the refrigeration chamber, the opening and closing of the damper is synchronized with the overall refrigeration control logic, achieving refined temperature control during normal refrigeration.

[0011] In some embodiments of this application, controlling the opening and closing of the damper based on the first temperature collected by the first temperature sensor includes: When the first temperature is detected to be greater than or equal to the first preset temperature, the damper is controlled to open to deliver cold air to the refrigeration chamber. When the first temperature is detected to be less than or equal to the third preset temperature, the damper is controlled to close to stop supplying cold air to the refrigeration chamber. The first preset temperature is greater than the second preset temperature.

[0012] The above technical solution has the following advantages or beneficial effects: In this embodiment, the first temperature collected by the first temperature sensor is used as the judgment basis, and a first preset temperature with a larger value and a third preset temperature with a smaller value are set as the damper opening and closing thresholds. When the first temperature is greater than or equal to the first preset temperature, the damper is opened to deliver cold air to the refrigerator cavity; when the first temperature is less than or equal to the third preset temperature, the damper is closed to stop the delivery of cold air. By controlling the opening and closing of the damper through two differentiated temperature thresholds, a stable temperature control range can be formed, avoiding frequent opening and closing of the damper. This not only keeps the temperature at the top of the refrigerator cavity within a reasonable range, ensuring the cooling effect of the refrigerator area, but also effectively reduces component wear and improves the stability of the overall machine operation.

[0013] In some embodiments of this application, after controlling the damper to open, the method further includes: The timing is started in response to the opening action of the damper, and the second temperature collected by the second temperature sensor is acquired at preset time intervals; If the second temperature does not decrease when the cumulative time reaches the first set time, it is determined that the air volume of the main air supply duct is insufficient. Increase the speed of the fan to increase the air volume supplied by the main air duct.

[0014] The above technical solution has the following advantages or beneficial effects: In this embodiment, timing is started immediately after the damper is opened, and the second temperature collected by the second temperature sensor is continuously acquired at preset time intervals. When the accumulated timing reaches a first set duration, the airflow status of the main air supply duct is determined based on whether the second temperature has decreased. When it is determined that the airflow is insufficient, the airflow of the main air supply duct is increased by increasing the fan speed. This can promptly compensate for the airflow deficiency, ensure that cold air can be effectively delivered to the bottom of the refrigerator cavity, improve the cooling effect in the lower part of the refrigerator cavity, avoid local cooling lag caused by insufficient airflow, and further improve the uniformity and operational reliability of the entire cooling system.

[0015] In some embodiments of this application, after determining a cooling malfunction, the method further includes: The measured temperature difference between the top and bottom of the refrigeration cavity is obtained by subtracting the second temperature from the first temperature. The temperature difference deviation value is obtained by subtracting the preset reference temperature difference from the measured temperature difference. The temperature difference deviation value is compared with a first preset difference value; If the temperature difference deviation value is less than the first preset difference value and the condition continues for a first preset time, it is determined that there is a frost accumulation blockage fault in the return air duct. The defrosting procedure is initiated to melt the frost accumulated in the return air duct.

[0016] The above technical solution has the following advantages or beneficial effects: In this embodiment, after determining a cooling anomaly, the measured temperature difference between the top and bottom of the refrigerator cavity is calculated using a first temperature and a second temperature. This difference is then combined with a preset reference temperature difference to obtain the temperature difference deviation value, which is compared with a first preset difference. If the temperature difference deviation value remains less than the first preset difference for a first preset duration, a frost blockage fault in the return air duct can be accurately determined, and the defrosting program can be initiated promptly to melt the frost in the return air duct. This method relies on temperature data collected by dual sensors to achieve accurate fault identification, allowing for immediate location of frost accumulation in the return air duct and immediate defrosting operations. This effectively clears the return air duct, restores normal airflow circulation, eliminates cooling anomalies caused by frost blockage, and ensures the continuous and stable operation of the refrigerator's air supply and refrigeration systems.

[0017] In some embodiments of this application, after controlling the start of the defrosting procedure, the method further includes: After the defrosting process is completed and the refrigerator resumes cooling operation, if the temperature difference deviation value is continuously less than the first preset difference value within a preset number of consecutive cooling cycles, it is determined that the air distribution in the main air duct is uneven. The rotation angle of the damper blades is controlled and adjusted so that cold air flows out from the gap below the damper, thereby increasing the airflow delivered to the bottom of the refrigeration chamber.

[0018] The above technical solution has the following advantages or beneficial effects: In this embodiment, after the defrosting process is completed and the refrigerator resumes cooling operation, the temperature difference deviation value is continuously monitored. If this value is consistently less than a first preset difference value within a preset number of cooling cycles, it is accurately determined that there is an uneven air distribution problem in the main air duct. By adjusting the rotation angle of the damper blades, cold air is guided to flow out from the gap below the damper, thereby increasing the airflow delivered to the bottom of the refrigerator cavity. This effectively optimizes the cold air distribution, improves the problem of a large temperature difference between the top and bottom of the refrigerator cavity, makes the cooling effect in each area of ​​the refrigerator cavity more balanced, and ensures the overall cooling performance of the refrigerator is stable.

[0019] In some embodiments of this application, after determining a cooling malfunction, the method further includes: The measured temperature difference between the top and bottom of the refrigeration cavity is obtained by subtracting the second temperature from the first temperature. The temperature difference deviation value is obtained by subtracting the preset reference temperature difference from the measured temperature difference. The temperature difference deviation value is compared with the second preset difference value; If the temperature difference deviation value is greater than the second preset difference value and the condition continues for the second preset time, the fault type is determined to be at least one of the following: abnormal mechanical positioning of the damper, damper icing and jamming, and frost accumulation and blockage of the main air supply duct.

[0020] The above technical solution has the following advantages or beneficial effects: In this embodiment, after determining a refrigeration abnormality, the measured temperature difference between the top and bottom of the refrigerator cavity is calculated using a first temperature and a second temperature. This difference is then combined with a preset reference temperature difference to obtain a temperature difference deviation value, which is compared with a second preset difference value. If the temperature difference deviation value remains greater than the second preset difference value for a second preset duration, at least one of the following faults is identified: abnormal mechanical positioning of the damper, damper icing and jamming, or frost accumulation and blockage in the main air duct. This method, relying on dual-temperature data acquisition and temperature difference determination logic, can quickly identify various common air supply and damper faults, effectively distinguishing fault types and providing accurate basis for subsequent targeted fault handling. This facilitates timely elimination of potential faults and maintains the refrigerator's normal refrigeration operation.

[0021] In some embodiments of this application, the damper is driven by a stepper motor, and the opening and closing angle of the blades and the guide position are controlled by a preset number of steps. The damper integrates a heating element. After determining that the fault type is at least one of the following: abnormal mechanical positioning of the damper, damper icing and jamming, and frost accumulation and blockage of the main air supply duct, the method further includes: The damper blades are controlled to reset and calibrate throughout their full stroke, and the reference operating position of the stepper motor is recalibrated to perform damper reset. If the temperature difference deviation value continues to be greater than the second preset difference value within the third preset time period after the damper reset is completed, the damper is controlled to close and the heating element is turned on to heat the damper. When the heating time for the heating element to heat the damper reaches the fourth preset time, the heating element is controlled to be turned off and the damper is controlled to be reopened. If the temperature difference deviation value continues to be greater than the second preset difference value within the fifth preset time period after the damper is opened, the defrosting program is started and the heating element is turned on to heat the damper. The defrosting procedure is repeated according to a preset cycle until the temperature difference deviation value is within the preset normal temperature difference range, at which point the periodic defrosting is stopped and the heating element is turned off.

[0022] The above technical solution has the following advantages or beneficial effects: In this embodiment, for a damper driven by a stepper motor and integrating a heating element, after determining that there is a fault such as abnormal damper mechanical positioning, damper icing and jamming, or frost accumulation and blockage in the main air supply duct, a multi-level fault handling process is executed sequentially. First, the damper blades are controlled to reset and calibrate the full stroke and the reference operating position of the stepper motor is recalibrated to complete the damper reset, which can effectively correct the damper mechanical positioning deviation. If the temperature difference deviation value still exceeds the second preset difference value within the third preset time after reset, the damper is controlled to close and the heating element is turned on to heat the damper, thereby eliminating the damper icing and jamming problem. When the heating time reaches the fourth preset time, the heating element is turned off and the damper is reopened to check the operating status again. If the temperature difference deviation value still exceeds the second preset difference value within the fifth preset time after the damper is opened, the defrosting program is started and the heating element is turned on simultaneously. The defrosting program is repeated according to the preset cycle until the temperature difference deviation value falls back to the preset normal temperature difference range, then the periodic defrosting is stopped and the heating element is turned off. This layered and progressive processing logic can troubleshoot and resolve various faults such as mechanical misalignment, icing, and frost buildup in the air ducts step by step. The fault handling is comprehensive and highly targeted, effectively restoring the opening and closing angle and airflow function of the damper, clearing the air supply path, ensuring the normal operation of the air supply system, and improving the stability of the refrigerator's operation and its self-repair capability.

[0023] In some embodiments of this application, the method further includes: During the operation of the refrigerator, when the first temperature or the second temperature is detected to be lower than the preset low temperature threshold, the defrosting program is initiated.

[0024] The above technical solution has the following advantages or beneficial effects: In this embodiment, during the operation of the refrigerator, the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor are monitored in real time. Once the first temperature or the second temperature is detected to be lower than a preset low temperature threshold, the defrosting program is immediately initiated. This method can promptly detect abnormalities such as excessively low local temperatures in the refrigerator compartment, eliminate the adverse effects of abnormal low temperatures through defrosting, and prevent the continuous interference of refrigeration and airflow due to excessively low temperatures and frost accumulation. This effectively ensures that the temperature of the refrigerator compartment is within a reasonable range, improving the safety and stability of the refrigerator's overall operation.

[0025] To achieve the above objectives, a first aspect of this application provides a refrigerator, the refrigerator comprising: The box contains a refrigeration chamber and a freezing chamber. A refrigeration system, comprising a compressor, a condenser, a capillary tube, and an evaporator connected in series to form a loop; An air supply system, comprising a fan, a main air supply duct, dampers, and a return air duct; The freezer chamber is equipped with an evaporator air duct compartment. The evaporator and the fan are both installed in the evaporator air duct compartment. The evaporator air duct compartment is provided with a communication port to communicate with the storage space of the freezer chamber. One end of the main air supply duct is connected to the evaporator air duct compartment, and the other end of the main air supply duct is connected to the top of the refrigerator compartment. The main air supply duct is used to unidirectionally transport the cold air circulated in the freezer compartment to the refrigerator compartment. The damper is located inside the main air supply duct, and the damper is used to adjust the amount and direction of cold air flowing into the refrigeration chamber in the main air supply duct. One end of the return air duct is connected to the return air inlet at the bottom of the refrigeration chamber, and the other end of the return air duct flows back into the evaporator air duct compartment. The temperature detection assembly includes a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is disposed at the top of the refrigeration cavity and the second temperature sensor is disposed at the bottom of the refrigeration cavity; The controller is electrically connected to the fan, the damper, the first temperature sensor, and the second temperature sensor, respectively, and is used to execute the method described in the first aspect of the embodiments of this application.

[0026] The above technical solution has the following advantages or beneficial effects: In this embodiment, a complete refrigeration and air supply structure is constructed by separately setting up a refrigerator cavity and a freezer cavity inside the refrigerator, combined with a refrigeration system consisting of a compressor, condenser, capillary tube, and evaporator, and an air supply system including a fan, main air duct, damper, and return air duct. A temperature detection component consisting of a first temperature sensor and a second temperature sensor is arranged at the top and bottom of the refrigerator cavity, respectively, enabling real-time acquisition of temperature data at different locations within the refrigerator cavity. A controller electrically connected to the fan, damper, and both temperature sensors can stably execute the aforementioned refrigerator control method, performing a series of control actions such as condition determination, damper adjustment, fan speed control, fault identification, and defrosting based on the acquired first and second temperatures. The entire hardware structure is rationally laid out, with smooth coordination among components, enabling comprehensive and accurate monitoring of the refrigerator cavity temperature status and achieving intelligent management and autonomous fault handling, effectively ensuring uniform and stable refrigerator cavity temperature, and improving the overall refrigeration effect, operational reliability, and user experience. Attached Figure Description

[0027] Figure 1 This is a front view of a refrigerator according to an embodiment of this application.

[0028] Figure 2 for Figure 1 A cross-sectional view.

[0029] Figure 3 This is a schematic diagram of the side cross-sectional structure of a refrigerator provided in one embodiment of this application.

[0030] Figure 4 This is a first flowchart of a refrigerator control method provided in an embodiment of this application.

[0031] Figure 5 This is a second flowchart of a refrigerator control method provided in an embodiment of this application.

[0032] Figure 6 This is a flowchart of the steps performed after the control damper is opened, according to an embodiment of this application.

[0033] Figure 7 This is a third flowchart of a refrigerator control method provided in an embodiment of this application.

[0034] Figure 8 This is the fourth flowchart of a refrigerator control method provided in an embodiment of this application.

[0035] Figure 9 This is the fifth flowchart of a refrigerator control method provided in an embodiment of this application.

[0036] Figure 10 This is the sixth flowchart of a refrigerator control method provided in an embodiment of this application.

[0037] Explanation of reference numerals in the attached figures: 1. Cabinet body; 11. Refrigeration chamber; 12. Freezing chamber; 13. Cabinet door; 14. Evaporator; 15. Evaporator air duct compartment; 16. Compressor compartment; 17. Fan; 18. Main air supply duct; 19. Air damper; 20. Return air duct; 21. First temperature sensor; 22. Second temperature sensor. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0039] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0041] Traditional air-cooled refrigerators typically only have a single temperature sensor in the refrigerator compartment. Relying solely on the temperature data collected from this single point to determine the overall refrigeration operation is insufficient to fully represent the true temperature distribution differences between the upper and lower areas of the refrigerator compartment. If malfunctions occur in the refrigerator compartment, such as increased airflow resistance, frost buildup on the duct walls, or malfunctioning dampers, the single-point temperature measurement method cannot quickly and accurately detect these abnormal cooling conditions. This easily leads to distorted temperature readings, preventing the refrigerator from promptly implementing corresponding adjustments and repairs. Ultimately, this reduces the overall temperature uniformity of the refrigerator compartment, impairing the preservation and storage of food within.

[0042] Based on this, this application provides a refrigerator and its control method, which aims to comprehensively determine the refrigeration condition by calculating the temperature difference at two temperature detection points at the top and bottom of the refrigeration cavity, thereby comprehensively and accurately identifying normal and abnormal refrigeration states and improving the accuracy and reliability of refrigerator refrigeration status determination.

[0043] Please see Figures 1 to 2 As shown, Figure 1 This is a front view of a refrigerator according to an embodiment of this application. Figure 2 for Figure 1A cross-sectional view. The refrigerator provided in this embodiment may include a cabinet 1. The cabinet 1 may have a hollow structure such as a cuboid. The cabinet 1 forms the outer shell of the refrigerator. It should be noted that the cabinet 1 may also have a hollow shell structure of other shapes.

[0044] In some embodiments, the interior of the housing 1 may have a plurality of compartments, each of which may include a refrigerator compartment 11 and a freezer compartment 12. The refrigerator compartment 11 and the freezer compartment 12 may be configured as multiple storage compartments. The housing 1 may have an upper cavity and a lower cavity that are spaced apart vertically, the upper cavity being either the refrigerator compartment 11 or the freezer compartment 12, and the lower cavity being either the refrigerator compartment 11 or the freezer compartment 12.

[0045] In some embodiments, the refrigeration chamber 11 and the freezing chamber 12 can serve as independent storage spaces to meet different refrigeration needs, such as freezing and refrigeration, depending on the type of food, and to store items that require refrigeration or freezing. The refrigeration chamber 11 and the freezing chamber 12 can be arranged vertically.

[0046] In some embodiments, the refrigerator may include a refrigerator liner. A refrigerator compartment 11 and a freezer compartment 12 may be formed within the refrigerator liner.

[0047] Please see Figure 1 As shown, in some embodiments, the refrigerator may include a door 13. The door 13 may be hinged to the front side of the body 1 for opening and closing the refrigerator compartment 11 and the freezer compartment 12.

[0048] It should be noted that multiple doors 13 can be provided. Each door 13 can be provided in a one-to-one correspondence with a refrigerator compartment 11 and a freezer compartment 12. One refrigerator compartment 11 can be provided with one or more doors 13, and one freezer compartment can also be provided with one or more doors 13.

[0049] In some embodiments, a compressor compartment may be provided inside the housing 1. A compressor may be installed inside the compressor compartment. The compressor compartment may be located in the bottom region of the housing 1. The compressor compartment may be located below the rear side of the refrigeration chamber 12. The compressor, condenser, throttling device, etc., may be installed inside the housing 1.

[0050] In some embodiments, the refrigerator may include a refrigeration system. The refrigeration system may be located inside the refrigerator body 1. The refrigeration system provides cold air to the interior of the refrigerator to maintain a low-temperature environment in each of the refrigeration compartments 11 and the freezer compartment 12. A refrigeration system is a system that uses refrigerant circulation to lower the temperature, and mainly includes major components such as a compressor, condenser, throttling element, and evaporator. The refrigeration system achieves a cooling effect by circulating refrigerant to transfer heat from a low-temperature object to a high-temperature object.

[0051] In some embodiments, the refrigeration system may include a compressor (not shown). The compressor can serve as the power source for the refrigeration cycle of the refrigeration chamber 11 and the freezing chamber 12, drawing in low-temperature, low-pressure refrigerant gas and compressing it into high-temperature, high-pressure gas. The compressor can deliver the high-temperature, high-pressure refrigerant to the condenser.

[0052] In some embodiments, the refrigeration system may include a condenser (not shown). The condenser can be used to receive refrigerant flowing from the compressor, cooling the high-temperature, high-pressure refrigerant gas from the compressor and converting it into a liquid state. The condenser can transfer heat from the refrigerant to the surrounding air, thus lowering the temperature of the refrigerant.

[0053] In some embodiments, the refrigeration system may include a throttling device (not shown). A condenser can deliver condensed refrigerant to the throttling device. The throttling device may be a capillary tube. The throttling device can be used to reduce the pressure of the refrigerant.

[0054] In some embodiments, refer to Figure 3 , Figure 3 This is a side cross-sectional view of a refrigerator according to an embodiment of this application. The refrigeration system may include an evaporator 14. A throttling device can deliver the throttled and depressurized refrigerant to the evaporator 14. The evaporator 14 can be used for the refrigerant vapor to evaporate and boil, so as to absorb heat from the surrounding medium.

[0055] In some embodiments, the compressor, condenser, throttling device, and evaporator can be connected in sequence to form a refrigeration circuit. The refrigerant can circulate within the refrigeration circuit to cool the refrigeration chamber 11 and the freezing chamber 12 inside the housing 1.

[0056] In some embodiments, refer to Figure 3The refrigerator has an evaporator air duct compartment 15 inside the freezer cavity 12. The evaporator 14 is fully housed and assembled inside the cavity of the evaporator air duct compartment 15. A connecting port is provided on the side wall of the evaporator air duct compartment 15, allowing airflow between the internal cavity of the evaporator air duct compartment 15 and the storage space of the freezer cavity 12. During the operation of the refrigeration system, the refrigerant evaporates and absorbs heat inside the evaporator 14, causing the air inside the evaporator air duct compartment 15 to continuously cool down and form low-temperature cold air. Through the connecting port, the cold air in the evaporator air duct compartment 15 can diffuse outwards to the storage area of ​​the freezer cavity 12, where it undergoes sufficient convection heat exchange with the air inside the freezer cavity 12, maintaining the required low-temperature storage environment of the freezer cavity 12. Simultaneously, the air heated up after heat exchange in the freezer cavity 12 can also flow back into the evaporator air duct compartment 15 through the connecting port, where it exchanges heat again with the evaporator 14 to achieve a secondary cooling, thus forming a continuously circulating cold air loop between the freezer cavity 12 and the evaporator air duct compartment 15. The evaporator air duct compartment 15 can form a barrier to enclose the evaporator 14, concentrate the cold energy generated by the evaporator 14, and reduce the ineffective loss of cold energy to the outside. This not only improves the refrigeration efficiency of the freezer chamber 12, but also integrates the evaporator 14, fan and other components into an independent air supply unit, providing a centralized cold source for the subsequent delivery of cold air to the refrigerator chamber through the main air supply duct.

[0057] Continue to refer to Figure 3 In some embodiments, a compressor compartment 16 may be provided inside the housing 1. A compressor may be installed inside the compressor compartment 16. The compressor compartment 16 may be located in the bottom region of the housing 1. The compressor compartment 16 may be located below the rear side of the refrigeration chamber 11. The compressor, condenser, throttling device, etc., may be located inside the housing 1.

[0058] It should be noted that in some other embodiments, the compressor compartment 16 may also be located at the top or side of the housing 1.

[0059] Continue to refer to Figure 3 In some embodiments, the refrigerator may include an air supply system, which may include main components such as a fan 17, a main air supply duct 18, an air damper 19, and a return air duct 20. The air supply system can be used in conjunction with the refrigeration system to complete the centralized generation, directional delivery, and recirculation of cold air, realizing a complete airflow circulation of self-circulating refrigeration in the freezer chamber 12 and unidirectional cooling from the freezer chamber to the refrigerator chamber.

[0060] The fan 17 can be arranged in the evaporator air duct compartment 15. As an airflow driving component, the fan 17 can drive the low-temperature cold air formed by heat exchange around the evaporator 14 to flow. Part of the cold air enters the storage space of the freezer chamber 12 through the connecting port of the evaporator air duct compartment 15 to complete the internal air circulation heat exchange of the freezer chamber 12 to maintain the low-temperature freezing environment. Another part of the cold air is driven by the fan 17 to flow into the main air supply duct 18 and is transported unidirectionally to the top of the refrigerator chamber 11 by the main air supply duct 18 to realize the cooling of the refrigerator chamber.

[0061] Specifically, during the operation of the refrigeration system, the low-temperature cold air generated by the evaporator 14 accumulates in the evaporator air duct compartment 15. The fan 17 operates to generate air pressure, which on the one hand pushes the cold air in the compartment through the connection port of the evaporator air duct compartment 15 into the storage space of the freezer cavity 12, forming convection heat exchange inside the freezer cavity 12 and maintaining the low-temperature storage environment of the freezer cavity 12. On the other hand, the remaining low-temperature cold air in the evaporator air duct compartment 15 is forced into the main air supply duct 18, so that the cold air is transported along the main air supply duct 18 to the top of the refrigerator cavity 11, supplying cooling capacity to the refrigerator cavity 11.

[0062] The fan 17 can be adjusted in speed with the controller. When the air volume delivered to the main air duct is insufficient, the controller can increase the operating speed of the fan 17, increase the airflow output of the duct, supplement the cold air delivered to the bottom of the refrigerator compartment 11, and reduce the temperature difference between the upper and lower areas of the refrigerator compartment 11. At the same time, the fan 17 can continuously provide circulation power, causing the air heated by heat exchange in the refrigerator compartment 11 to flow back to the evaporator duct compartment 15 through the return air duct 20, and re-exchange heat with the evaporator 14 to cool down, completing the closed-loop circulation of airflow throughout the machine. During the defrosting process, the fan 17 can stop operating according to the control logic to prevent the hot and humid air generated during defrosting from spreading to the freezer compartment and refrigerator compartment, ensuring the smooth completion of the defrosting operation and reducing the problems of frost and condensation in the compartment.

[0063] One end of the main air supply duct 18 is directly connected to the evaporator air duct compartment 15, and the other end extends and connects to the top of the refrigerator cavity 11, forming an independent airflow channel for supplying cooling from the cold source on the freezing side to the refrigerator cavity 11. Relying on the wind pressure generated by the fan 17 in the evaporator air duct compartment 15, the low-temperature cold air generated by the heat exchange of the evaporator 14 and which has completed the internal circulation heat exchange of the freezing cavity 12 can be unidirectionally drawn into the main air supply duct 18. The air duct's sealed structure can reduce the loss of cold air during the cold air transportation process, ensuring that the low-temperature airflow is completely delivered to the top of the refrigerator cavity 11. After entering the cavity from the top of the refrigerator cavity 11, the cold air sinks downwards by its own weight, completing the heat exchange and cooling of the entire refrigerator cavity 11.

[0064] A damper 19 is installed inside the main air supply duct 18. The damper 19 can adjust the cross-sectional area of ​​the duct to change the volume and direction of the cold air delivered to the refrigerator compartment 11. The main air supply duct 18 only allows cold air to flow unidirectionally from the evaporator duct compartment 15 to the refrigerator compartment 11, preventing the hot air after heat exchange in the refrigerator compartment 11 from flowing back to the freezer side and avoiding hot air entering the evaporator duct compartment 15 to increase the evaporator's cooling load. In the overall airflow circulation, the main air supply duct 18 plays a core guiding role in the dual-chamber cooling distribution of the freezer and refrigerator compartments 11. Together with the return air duct 20, it forms a complete closed-loop airflow path, ensuring the stable realization of the air supply logic of priority cooling in the freezer compartment and top air intake in the refrigerator compartment 11 under the single evaporator system, effectively improving the temperature uniformity of the refrigerator compartment.

[0065] The damper 19 is located inside the main air supply duct 18. The damper 19 can be used to adjust the flow rate and direction of the cold air flowing into the refrigeration chamber 11 in the duct. It can dynamically switch on and off according to the real-time temperature of the refrigeration chamber 11, adjust the cold air supply, and balance the air flow rate in the upper and lower areas of the refrigeration chamber 11.

[0066] In some embodiments, the damper 19 can be composed of four parts: a stepper motor drive assembly, damper blades, a heating element, and a mounting base, forming a complete integrated adjustment structure.

[0067] The mounting base can be sealed and fixed to the inner wall of the main air supply duct 18. An airflow hole matching the duct diameter is opened in the middle of the base to provide a basic channel for the passage of cold air.

[0068] The stepper motor is fixedly installed on one side of the base. The motor output shaft is rigidly connected to the damper blade. The stepper motor can precisely control the rotation angle of the shaft according to the number of pulse steps issued by the controller, thereby driving the damper blade to deflect synchronously. The air volume is adjusted by the size of the area of ​​the air passage blocked by the blade. At the same time, the direction of the cold air outlet is changed by the different deflection postures of the blade.

[0069] The damper blades can be a guide plate structure with a gap fit between the blade edge and the inner wall of the air duct. When the blades are fully closed, they can completely block the airflow holes at the base, preventing the evaporator air duct chamber 15 from supplying cold air to the refrigerator chamber 11. When the blades are partially deflected, ventilation gaps of different sizes can be reserved at the top and bottom. When the controller determines that the temperature difference between the top and bottom of the refrigerator chamber is too large, the stepper motor can adjust the blade angle so that the cold air flows out from the gap below the blades, increasing the air volume at the bottom of the refrigerator chamber.

[0070] The heating element can be attached to the windward side surface of the damper blade and the mounting base. The heating element is electrically connected to the controller and can be powered on to heat up when the damper 19 is stuck due to icing, melting the frost attached to the blade, base and the inner wall of the surrounding air duct, and relieving the blade rotation obstruction.

[0071] The mechanical rotation stroke of damper 19 is equipped with a full-stroke limit structure. The controller can control the blade to perform a full-stroke reciprocating reset action, and simultaneously complete the recalibration of the stepper motor reference running position, correct the mechanical positioning offset caused by long-term operation, and ensure the control accuracy of the blade opening and closing angle and the guide position.

[0072] The damper 19 integrates multiple functions such as airflow interruption, stepless air volume adjustment, airflow guidance, defrosting and heating, and mechanical reset calibration. Its compact design fits the small installation space inside the main air duct 18 without requiring additional storage space in the cabinet. It can stably and precisely control the cold air supply to the refrigeration side compartment in a single evaporator air supply system.

[0073] Meanwhile, the air supply system can work with the refrigerator's controller to execute a complete set of temperature control and fault handling logic: after the damper 19 is opened, the insufficient air supply volume can be compensated by adjusting the fan speed. When faults such as frost accumulation in the return air duct 20, damper 14 jamming, and uneven air distribution are identified, the airflow state is optimized by relying on the control actions such as damper 19 angle adjustment, fan 17 speed adjustment, and defrosting heating to ensure uniform cold air distribution in the refrigerator and freezer compartments, reduce the temperature difference between the upper and lower parts of the compartments, and stabilize the dual-compartment cooling effect.

[0074] The inlet of the return air duct 20 is connected to the return air port at the bottom of the refrigeration chamber 11, and the outlet is centrally connected to the evaporator duct compartment 15, forming a complete airflow circulation loop in the refrigeration chamber in conjunction with the main supply air duct 18. During the operation of the unit, the low-temperature cold air delivered to the top of the refrigeration chamber 11 through the main supply air duct 18 descends from top to bottom, gradually completing the heat exchange inside the refrigeration chamber 11 and absorbing heat from the chamber to raise its temperature. The heated air gathers at the bottom of the refrigeration chamber 11 and can smoothly flow into the return air duct 20 through the bottom return air port.

[0075] Under the negative pressure suction effect generated by the continuous operation of the fan 17, the heat exchange air that flows into the return air duct 20 can flow back to the evaporator air duct chamber 15 along the duct pipeline, and re-exchange heat with the evaporator 14 to cool down, and then be converted into low-temperature cold air to participate in the next round of air supply cycle. In this way, the airflow in the cold storage chamber 11 is continuously closed-loop circulated, which effectively improves the utilization rate of cold energy and avoids problems such as temperature control lag and severe temperature stratification caused by the heat exchange air remaining in the chamber.

[0076] Meanwhile, the return air duct 20 adopts a bottom return air structure, which can fully adapt to the top air intake and bottom return air supply logic of the refrigerator cavity 11 in this embodiment. It can promptly exhaust the hot and humid air in the cavity for recirculation, reducing the risk of condensation and frost formation inside the refrigerator cavity 11. Furthermore, the diameter structure of the return air duct 20 ensures smooth airflow. When frost accumulates and blocks the inner wall of the duct, it directly leads to obstruction of the return airflow and an imbalance in the hot and cold air circulation in the refrigerator cavity 11, manifesting as an abnormal temperature difference between the top and bottom of the refrigerator cavity 11. This provides a structural basis for the system to determine the return air frost accumulation fault and trigger the defrosting self-repair procedure based on the temperature difference deviation value. The return air duct structure is rationally laid out with a clear airflow path. Combined with the single evaporator refrigeration air supply architecture, it effectively ensures the stability and continuity of the airflow circulation in both the freezer and refrigerator cavities, improving the overall temperature control uniformity and operational reliability.

[0077] It should be noted that in this embodiment, the refrigeration system is a single evaporator refrigeration system. The freezing chamber 12 and the refrigeration chamber 11 share the same evaporator 14 as the sole cold source. The entire refrigeration cycle uses only one evaporator 14, relying on the refrigerant to evaporate and absorb heat within the evaporator 14 to uniformly prepare low-temperature cold air. When the refrigeration system is running, the evaporator 14 continuously cools the air in the air duct chamber to form cold air. Driven by the fan 17, the cold air preferentially flows into the interior of the freezing chamber 12 through the connection port of the evaporator air duct chamber 15, where it fully convects and exchanges heat with the air in the storage space of the freezing chamber 12, completing the cooling of the freezing chamber 12 and meeting the requirements for low-temperature freezing storage. After completing the heat exchange in the freezing chamber 12, the low-temperature cold air can be diverted into the main air duct 18 connected to the evaporator air duct chamber 15 under the action of the fan pressure. It is then transported along the main air duct 18 to the top of the refrigeration chamber 11 and sent into the chamber from the top. The refrigeration of the refrigeration chamber 11 is achieved by the downward settling of the cold air. The air heated by absorbing heat inside the refrigeration chamber 11 flows into the return air duct 20 through the return air inlet at the bottom of the refrigeration chamber 11. It then flows back to the evaporator duct chamber 15 along the return air duct 20, where it comes into contact with the evaporator 14 again for heat exchange and cooling, transforming back into low-temperature cold air to participate in the next round of airflow circulation. This single evaporator structure relies on only one evaporator to simultaneously provide cooling to both the freezing chamber 12 and the refrigeration chamber 11. The airflow path, where cold air first flows through the freezing chamber 12 and then supplies the top of the refrigeration chamber 11, is simple and eliminates the need for an additional refrigeration evaporator, reducing the overall component cost. Furthermore, the use of air ducts and dampers enables independent temperature control for both chambers, balancing freezing capacity with refrigeration temperature uniformity.

[0078] In some embodiments, continue to refer to Figure 3 The refrigerator may also include a temperature detection component. The temperature detection component includes a first temperature sensor 21 and a second temperature sensor 22. The first temperature sensor 21 is located at the top of the refrigerator compartment 11, and the second temperature sensor 22 is located at the bottom of the refrigerator compartment 11.

[0079] Specifically, two temperature sensors are positioned at different vertical locations within the refrigerator cavity 11 to achieve differentiated temperature acquisition between the upper and lower regions of the refrigerator cavity 11. The first temperature sensor 21 is fixedly installed at the top of the refrigerator cavity 11, corresponding to the cold air outlet of the main air duct 18, and can accurately acquire the real-time temperature of the air inlet side at the top of the refrigerator cavity 11. The second temperature sensor 22 is fixedly installed at the bottom of the refrigerator cavity 11, corresponding to the air return side, and is used to acquire the real-time temperature of the return side at the bottom of the refrigerator cavity 11. Both the first temperature sensor 21 and the second temperature sensor 22 are electrically connected to the refrigerator controller, and can transmit the acquired first and second temperature data to the controller in real time and without interruption. Based on the two highly differentiated temperature data sets, the controller can calculate the measured temperature difference between the top and bottom of the refrigerator cavity 11, and combine it with a preset reference temperature difference to obtain the temperature difference deviation value. This accurately characterizes the temperature stratification state and cold air circulation conditions inside the refrigerator cavity, which differs from the single-point temperature measurement method of traditional refrigerators. This dual-point temperature measurement structure can comprehensively reflect the true temperature distribution of the refrigerator cavity, providing accurate and reliable data support for the determination of refrigeration anomalies, identification of frost blockage in the return air duct, determination of uneven air distribution in the air supply duct, and self-repairing control logic such as air duct angle adjustment and defrosting program initiation. It effectively solves the problem that single-point temperature measurement cannot identify hidden faults such as temperature stratification in the cavity, abnormal air supply, and frost blockage in the air duct, ensuring the temperature control accuracy and temperature uniformity of the refrigerator cavity.

[0080] In some embodiments, the refrigerator also includes a controller (not shown in the figure). The controller is the core control unit of the refrigerator and can be electrically connected to the fan 17 of the air supply system, the air damper 19 with heating element, the first temperature sensor 21 and the second temperature sensor 22 of the temperature detection component, as well as the refrigeration system and the defrosting heating component. It can coordinate and execute the entire process control logic of the refrigerator's refrigeration regulation, operating condition monitoring, anomaly judgment, and fault self-repair. The controller can receive and analyze the first temperature at the top of the refrigerator compartment 11 collected by the first temperature sensor 21 and the second temperature at the bottom of the refrigerator compartment 11 collected by the second temperature sensor 22 in real time. It can calculate the measured temperature difference and temperature difference deviation value, and combine it with various preset thresholds, preset durations, and preset refrigeration cycles to accurately determine various operating conditions and faults such as refrigeration abnormalities, uneven air distribution in the main air supply duct, abnormal mechanical positioning of the air damper, air damper icing and jamming, and frost accumulation and blockage in the main air supply duct. Simultaneously, the controller can output corresponding control commands based on the judgment results, precisely controlling the operation of the stepper motor of the damper 19 to achieve full-stroke reset calibration of the damper blades, recalibration of the reference position, adjustment of the opening and closing angle, and opening and closing control, thereby adjusting the air volume and direction of the main air supply duct 18. It can also independently control the start and stop of the fan 17 and its operating speed, the opening and closing of the damper heating element, and the start, periodic operation, and stop of the defrosting program of the whole machine. In addition, the controller can promptly trigger the defrosting logic when it detects that the local temperature of the refrigerator cavity is lower than the preset low temperature threshold. After the fault is repaired and the temperature difference deviation value returns to the normal temperature difference range, it automatically terminates the defrosting and heating operations, realizing intelligent closed-loop control of refrigerator cooling air supply, fault self-diagnosis, and abnormal self-repair. It effectively adapts to the air supply architecture of single evaporator freezing first and then refrigeration, continuously corrects the temperature stratification problem in the refrigerator cavity, and ensures long-term stable and high-precision operation of the refrigerator.

[0081] Reference Figure 4 , Figure 4 This is a first flowchart of a refrigerator control method provided in an embodiment of this application, which is executed by the refrigerator controller and includes, but is not limited to, steps S410 to S460.

[0082] Step S410: Obtain the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor.

[0083] In this step, the controller reads in real time the first temperature collected by the first temperature sensor located at the top of the refrigerator compartment and the second temperature collected by the second temperature sensor located at the bottom of the refrigerator compartment. This solution addresses the problem of temperature lag in single-system air-cooled side-by-side refrigerators, where the refrigerator compartment is colder at the top and warmer at the bottom, and single-point temperature measurement is prone to detection delays. It employs a dual-point temperature measurement method to comprehensively capture the actual temperature status of different areas of the refrigerator compartment, avoiding the problem of missed detections caused by the limited sensing range of a single sensor.

[0084] Step S420: Subtract the first preset temperature from the first temperature to obtain the first temperature difference, and subtract the second preset temperature from the second temperature to obtain the second temperature difference.

[0085] In this step, the controller subtracts a preset first temperature from the acquired first temperature to calculate a first temperature difference, which characterizes the degree to which the temperature at the top of the refrigerator compartment deviates from the standard temperature. Simultaneously, the controller subtracts a preset second temperature from the second temperature to calculate a second temperature difference, which characterizes the degree to which the temperature at the bottom of the refrigerator compartment deviates from the standard temperature.

[0086] For example, the standard temperature at the top of the refrigerator compartment, i.e., the first preset temperature, is set to 2°C, and the standard temperature at the bottom of the refrigerator compartment, i.e., the second preset temperature, is set to 4°C. If the current value detected by the first temperature sensor is 2.2°C and the value detected by the second temperature sensor is 4.1°C, then the first temperature difference can be calculated to be 0.2°C and the second temperature difference to be 0.1°C.

[0087] Step S430: Determine whether the first temperature difference is within the first preset temperature fluctuation range.

[0088] In this step, the controller judges the calculated first temperature difference to confirm whether it falls within a predefined first preset temperature fluctuation range. This range is the normal allowable fluctuation range of the temperature at the top of the refrigerator compartment. For example, the first preset temperature fluctuation range can be set to [-0.5℃, +0.5℃]. As long as the first temperature difference is within this range, it means that the temperature at the top of the refrigerator compartment is compliant. Taking the example data above, the first temperature difference of 0.2℃ is within this fluctuation range, and the top temperature is determined to be normal.

[0089] Step S440: If the first temperature difference is within the first preset temperature fluctuation range, determine whether the second temperature difference is within the second preset temperature fluctuation range.

[0090] In this step, when the first temperature difference is within the first preset temperature fluctuation range and the temperature at the top of the refrigerator cavity is normal, the controller further verifies the second temperature difference to determine whether it is within the second preset temperature fluctuation range. For example, the second preset temperature fluctuation range is also set to [-0.5℃, +0.5℃]. Continuing with the above example, if the second temperature difference of 0.1℃ is within this range, the temperature at the bottom of the refrigerator cavity is also determined to be normal.

[0091] In step S450, if the second temperature difference is within the second preset temperature fluctuation range, the refrigeration is determined to be normal.

[0092] In this step, when the first temperature difference and the second temperature difference fall into their respective preset temperature fluctuation ranges, it indicates that the temperature at the top and bottom of the refrigerator cavity is stable within the allowable fluctuation range of the standard temperature, the overall temperature distribution of the refrigerator cavity is uniform, and there are no obvious abnormalities in components such as air supply, air duct, and damper. The controller ultimately determines that the refrigeration condition is normal, and the refrigerator maintains the normal refrigeration and air supply operation mode without the need to start fan speed adjustment, damper reset, heating, defrosting, or other intervention actions.

[0093] Step S460: If the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, then the refrigeration is determined to be abnormal.

[0094] In this step, if the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, the controller will determine that the cooling is abnormal if either condition is met. For example, if the first temperature is 3.2℃ and the calculated first temperature difference is 1.2℃, it exceeds the range of [-0.5℃, +0.5℃]; or if the second temperature is 4.8℃ and the second temperature difference is 0.8℃, it also exceeds the preset range; or if both temperature differences exceed the standard simultaneously, it will be determined that the cooling is abnormal. This abnormal state is usually caused by problems such as insufficient air volume in the refrigerator, frost accumulation and blockage in the air duct, stuck damper, and misaligned ice. The controller will then enter the subsequent fault type identification and classification handling process, sequentially performing operations such as fan speed adjustment, damper reset calibration, heating defrosting, and periodic defrosting to gradually eliminate the fault and correct the temperature state of the refrigerator cavity.

[0095] In this embodiment, relying on the temperature measurement data of the upper and lower dual sensors of the refrigeration cavity, full-area temperature verification can be achieved. Compared with the traditional single-point temperature measurement logic, it can accurately identify problems such as local temperature anomalies and uneven temperature stratification in the refrigeration cavity, and detect potential problems such as deterioration of air supply, frost in the air duct, and malfunction of the air damper in advance, so as to ensure the stability and compliance of the refrigeration temperature. At the same time, it makes subsequent fault handling actions more targeted. While improving the temperature control effect, it can also avoid the problem of increased energy consumption caused by ineffective defrosting.

[0096] Reference Figure 5 , Figure 5 This is a second flowchart of a refrigerator control method provided in an embodiment of this application, which is executed by the refrigerator controller and includes, but is not limited to, steps S510 to S5100.

[0097] Step S510: Obtain the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor.

[0098] Step S520: Subtract the first preset temperature from the first temperature to obtain the first temperature difference, and subtract the second preset temperature from the second temperature to obtain the second temperature difference.

[0099] Step S530: Determine whether the first temperature difference is within the first preset temperature fluctuation range.

[0100] Step S540: If the first temperature difference is within the first preset temperature fluctuation range, determine whether the second temperature difference is within the second preset temperature fluctuation range.

[0101] In step S550, if the second temperature difference is within the second preset temperature fluctuation range, then the refrigeration is determined to be normal.

[0102] Step S560: Detect whether the first temperature is greater than or equal to the first preset temperature.

[0103] Step S570: If the first temperature is greater than or equal to the first preset temperature, control the damper to open so as to deliver cold air to the refrigeration chamber.

[0104] Step S580: If the first temperature is less than the first preset temperature, then detect whether the first temperature is less than or equal to the third preset temperature.

[0105] In step S590, if the first temperature is less than or equal to the third preset temperature, the damper is closed to stop supplying cold air to the refrigeration chamber. If the first preset temperature is greater than the third preset temperature, the process returns to step S560.

[0106] In step S5100, if the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, then the refrigeration is determined to be abnormal.

[0107] In this embodiment, after determining that the cooling is normal, the controller also controls the damper to open or close based on the first temperature collected by the first temperature sensor. That is, when the first temperature is detected to be greater than or equal to the first preset temperature, the damper is controlled to open to deliver cold air to the refrigerator cavity; when the first temperature is detected to be less than or equal to the third preset temperature, the damper is controlled to close to stop delivering cold air to the refrigerator cavity, wherein the first preset temperature is greater than the third preset temperature.

[0108] Specifically, after the controller completes the refrigeration condition determination and confirms that the refrigeration state of the refrigerator cavity is normal, it will control the opening and closing of the dampers in the main air supply duct based on the first temperature collected by the first temperature sensor at the top of the refrigerator cavity, thereby realizing the automatic on / off regulation of the cold air supply to the refrigerator cavity. There are a first preset temperature and a third preset temperature preset, and the value of the first preset temperature is greater than the third preset temperature. The two thresholds constitute the temperature control range for the opening and closing of the dampers.

[0109] When the first temperature sensor detects in real time that the first temperature at the top of the refrigerator compartment is greater than or equal to the first preset temperature, the controller outputs a control signal to drive the damper to open, opening the airflow path of the main air supply duct. The cold air circulated in the evaporator duct chamber through the freezer chamber can then be normally delivered to the top of the refrigerator compartment, continuously supplying cooling capacity to the refrigerator compartment and achieving cooling inside the compartment. For example, if the first preset temperature is set to 4.5℃, and the currently collected first temperature is 4.8℃, which is greater than the first preset temperature, the controller will then control the damper to open and start the refrigerator cooling supply.

[0110] When the first temperature sensor detects that the first temperature has dropped to less than or equal to the third preset temperature, the controller controls the damper to close, cutting off the cold air delivery channel in the main air duct and stopping the supply of cold air to the refrigerator compartment to prevent the temperature in the refrigerator compartment from remaining too low. For example, the third preset temperature is set to 3.5℃, which is lower than the aforementioned first preset temperature. If the current first temperature drops to 3.2℃, meeting the condition of being less than or equal to the third preset temperature, the controller immediately controls the damper to close, suspending the refrigeration supply.

[0111] In this embodiment, the temperature at the top of the refrigerator cavity is used as the adjustment basis, and the circulatory opening and closing of the damper is achieved in conjunction with two temperature thresholds (high and low) to keep the refrigerator cavity temperature stably maintained between a third preset temperature and a first preset temperature. This method has a simple structural logic and timely response. Under normal refrigeration conditions, it can accurately control the cold supply to the refrigerator cavity, effectively constraining the refrigerator temperature within a reasonable range. This not only meets the low-temperature requirements for food storage but also avoids problems such as increased energy consumption and localized low temperatures caused by excessive refrigeration, further improving the overall temperature control accuracy and operational efficiency of the machine.

[0112] Reference Figure 6 , Figure 6 This is a flowchart of the steps performed after the control damper is opened, provided in an embodiment of this application. The steps are executed by the refrigerator's controller, including but not limited to steps S610 to S630.

[0113] Step S610: In response to the damper opening action, start timing and acquire the second temperature collected by the second temperature sensor according to the preset time interval.

[0114] In this step, after receiving the execution signal to open the damper, the controller immediately starts the timing function and continuously collects the second temperature detected by the second temperature sensor at preset time intervals. This temperature is the real-time temperature at the bottom of the refrigerator cavity. For example, the preset time interval for data collection is 1 minute to ensure continuous and consistent capture of temperature change trends.

[0115] In step S620, if the second temperature does not decrease when the accumulated time reaches the first set duration, it is determined that the air volume of the main air supply duct is insufficient.

[0116] In this step, when the accumulated timing reaches the first set time, the controller compares and analyzes the second temperature data collected throughout the process. If the second temperature does not show a decreasing trend throughout the entire timing period, it is determined that there is insufficient airflow in the main air supply duct. For example, the first set time is set to 10 minutes, and the timing is continuously recorded for 10 minutes after the damper is opened. During this period, the temperature at the bottom of the refrigerator compartment is collected every minute. If all the second temperature values ​​collected within 10 minutes do not decrease, it can be determined that the cold air delivery volume cannot meet the cooling requirements of the bottom of the refrigerator compartment, which is mostly caused by poor airflow in the duct or excessive air supply resistance.

[0117] Step S630: Control the fan speed to increase the air volume supplied by the main air supply duct.

[0118] In this step, after determining that the air supply volume is insufficient, the controller outputs a control command to increase the fan speed. After the fan speed is increased, the air pressure in the evaporator duct increases, and the airflow in the main air supply duct increases accordingly, enhancing the cold air delivery capacity and accelerating the cooling speed at the bottom of the refrigerator compartment. This can improve the problem of uneven temperature distribution in the refrigerator compartment, where the top is cold and the bottom is hot.

[0119] In this embodiment, based on the normal opening of the damper for cooling, hidden air supply abnormalities can be detected in a timely manner by relying on timed sampling and temperature trend judgment. The air volume can be adaptively adjusted without the need for additional detection devices, which effectively improves the overall temperature control uniformity of the refrigeration chamber and the reliability of the whole machine operation.

[0120] Reference Figure 7 , Figure 7 This is a third flowchart of a refrigerator control method provided in an embodiment of this application, which is executed by the refrigerator controller and includes, but is not limited to, steps S710 to S7160.

[0121] Step S710: Obtain the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor.

[0122] Step S720: Subtract the first preset temperature from the first temperature to obtain the first temperature difference, and subtract the second preset temperature from the second temperature to obtain the second temperature difference.

[0123] Step S730: Determine whether the first temperature difference is within the first preset temperature fluctuation range.

[0124] Step S740: If the first temperature difference is within the first preset temperature fluctuation range, determine whether the second temperature difference is within the second preset temperature fluctuation range.

[0125] In step S750, if the second temperature difference is within the second preset temperature fluctuation range, the refrigeration is determined to be normal.

[0126] Step S760: Detect whether the first temperature is greater than or equal to the first preset temperature.

[0127] In step S770, if the first temperature is greater than or equal to the first preset temperature, the damper is opened to deliver cold air to the refrigeration chamber.

[0128] Step S780: If the first temperature is less than the first preset temperature, then detect whether the first temperature is less than or equal to the third preset temperature.

[0129] In step S790, if the first temperature is less than or equal to the third preset temperature, the damper is closed to stop supplying cold air to the refrigeration chamber. If the first preset temperature is greater than the third preset temperature, the process returns to step S760.

[0130] In step S7100, if the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, then the refrigeration is determined to be abnormal.

[0131] Step S7110: Subtract the second temperature from the first temperature to obtain the measured temperature difference between the top and bottom of the refrigeration chamber.

[0132] Step S7120: Subtract the preset reference temperature difference from the measured temperature difference to obtain the temperature difference deviation value.

[0133] Step S7130: Determine whether the temperature difference deviation value is less than the first preset difference value.

[0134] In step S7140, if the temperature difference deviation value is less than the first preset difference value, determine whether the duration of the working condition where the temperature difference deviation value is less than the first preset difference value is greater than or equal to the first preset duration; if the temperature difference deviation value is greater than or equal to the first preset difference value, return to step S7130.

[0135] In step S7150, if the duration of the condition where the temperature difference deviation value is less than the first preset difference value is greater than or equal to the first preset duration, it is determined that there is a frost blockage fault in the return air duct; if the duration of the condition where the temperature difference deviation value is less than the first preset difference value is less than the first preset duration, then return to step S7140.

[0136] Step S7160: Control the start of the defrosting program to melt the frost accumulated in the return air duct.

[0137] In this embodiment, after the controller determines that the refrigeration condition is abnormal, it immediately enters the refrigerator cavity temperature difference analysis and fault identification process. Specifically, the controller retrieves the first temperature at the top of the refrigerator cavity collected by the first temperature sensor and the second temperature at the bottom of the refrigerator cavity collected by the second temperature sensor. By subtracting the second temperature from the first temperature, the measured temperature difference between the top and bottom of the refrigerator cavity is obtained. For example, if the detected first temperature at the top of the refrigerator cavity is 2°C and the second temperature at the bottom is 6°C, then the measured temperature difference is -4°C.

[0138] Next, the controller subtracts the preset reference temperature difference from the calculated measured temperature difference to obtain the final temperature difference deviation value. For example, if the preset reference temperature difference is set to -2℃, the temperature difference deviation value calculated based on the measured temperature difference is -2℃. This parameter can intuitively reflect the degree of deviation between the actual temperature difference in the refrigeration chamber and the standard temperature difference, and is the core basis for judging air duct malfunctions.

[0139] The controller determines whether the current temperature difference deviation is less than a first preset deviation value. For example, the first preset deviation value is set to -1.5℃, which serves as the threshold for determining whether the refrigerator compartment is cold at the top and hot at the bottom, or whether the return air circulation is obstructed. Using the data from the previous step, the current temperature difference deviation value of -2℃ is less than the first preset deviation value of -1.5℃, so the process proceeds to the next timing and determination stage; if the temperature difference deviation value is greater than or equal to the first preset deviation value, it indicates that the temperature difference in the refrigerator compartment is within a reasonable deviation range and there are no characteristics of return air blockage, so the process returns to step S7130 for continuous monitoring.

[0140] When the temperature difference deviation is less than a first preset value, the controller starts timing and continuously monitors the cumulative duration of this abnormal condition to determine whether the duration has reached or exceeded the first preset duration. For example, the first preset duration can be set to 40 minutes. If the cumulative duration does not reach this value, it indicates only a short-term temperature fluctuation and not permanent air duct blockage, and the process returns to step S7140 to continue timing monitoring. If the cumulative duration meets the requirement, i.e., when the duration of the temperature difference deviation being less than the first preset value is greater than or equal to the first preset duration, the controller determines that frost has accumulated inside the return air duct, causing a blockage. Frost accumulation in the return air duct leads to poor air return after heat exchange in the refrigeration chamber, insufficient bottom cooling, ultimately resulting in a lower top temperature, a higher bottom temperature, and a consistently smaller measured temperature difference. If the abnormal duration is less than the first preset duration, the monitoring continues cyclically.

[0141] Upon determining that the return air duct is blocked by frost, the controller immediately initiates the whole-unit defrosting program. The heating element melts the frost adhering to the inner wall of the return air duct, clearing the airflow path. After the frost is cleared, airflow circulation in the refrigerator compartment returns to normal, the temperature difference between the upper and lower zones gradually returns to the standard range, and the abnormal cooling condition is resolved.

[0142] In this embodiment, relying on the temperature difference calculation and time verification of dual temperature measuring points, short-term temperature fluctuations and frost accumulation faults in the return air duct can be accurately distinguished, realizing automatic fault identification and targeted repair, effectively solving the problems of temperature stratification and abnormal temperature control in the refrigerator cavity caused by return air blockage, and improving the stability of refrigerator operation and food storage effect.

[0143] Reference Figure 8 , Figure 8This is a fourth flowchart of a refrigerator control method provided in an embodiment of this application, which is executed by the refrigerator controller and includes, but is not limited to, steps S810 to S8210.

[0144] Step S810: Obtain the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor.

[0145] Step S820: Subtract the first preset temperature from the first temperature to obtain the first temperature difference, and subtract the second preset temperature from the second temperature to obtain the second temperature difference.

[0146] Step S830: Determine whether the first temperature difference is within the first preset temperature fluctuation range.

[0147] Step S840: If the first temperature difference is within the first preset temperature fluctuation range, determine whether the second temperature difference is within the second preset temperature fluctuation range.

[0148] In step S850, if the second temperature difference is within the second preset temperature fluctuation range, the refrigeration is determined to be normal.

[0149] Step S860: Detect whether the first temperature is greater than or equal to the first preset temperature.

[0150] In step S870, if the first temperature is greater than or equal to the first preset temperature, the damper is opened to deliver cold air to the refrigeration chamber.

[0151] Step S880: If the first temperature is less than the first preset temperature, then detect whether the first temperature is less than or equal to the third preset temperature.

[0152] In step S890, if the first temperature is less than or equal to the third preset temperature, the damper is closed to stop supplying cold air to the refrigeration chamber. If the first preset temperature is greater than the third preset temperature, the process returns to step S860.

[0153] In step S8100, if the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, then the refrigeration is determined to be abnormal.

[0154] Step S8110: Subtract the second temperature from the first temperature to obtain the measured temperature difference between the top and bottom of the refrigeration chamber.

[0155] Step S8120: Subtract the preset reference temperature difference from the measured temperature difference to obtain the temperature difference deviation value.

[0156] Step S8130: Determine whether the temperature difference deviation value is less than the first preset difference value.

[0157] In step S8140, if the temperature difference deviation value is less than the first preset difference value, determine whether the duration of the working condition where the temperature difference deviation value is less than the first preset difference value is greater than or equal to the first preset duration; if the temperature difference deviation value is greater than or equal to the first preset difference value, return to step S8130.

[0158] In step S8150, if the duration of the condition where the temperature difference deviation value is less than the first preset difference value is greater than or equal to the first preset duration, it is determined that there is a frost blockage fault in the return air duct; if the duration of the condition where the temperature difference deviation value is less than the first preset difference value is less than the first preset duration, then return to step S8140.

[0159] Step S8160: Control the start of the defrosting program to melt the frost accumulated in the return air duct.

[0160] In step S8170, after the defrosting process is completed, the compressor is turned on to perform cooling.

[0161] Step S8180: Determine whether the temperature difference deviation value is continuously less than the first preset difference value within a consecutive preset number of cooling cycles.

[0162] Step S8190: If the temperature difference deviation value is continuously less than the first preset difference value within a consecutive preset number of cooling cycles, it is determined that the air distribution in the main air supply duct is uneven.

[0163] In step S8200, the rotation angle of the damper blades is controlled and adjusted so that cold air flows out from the gap below the damper, thereby increasing the airflow delivered to the bottom of the refrigeration chamber.

[0164] In step S8210, if the temperature difference deviation value does not continuously decrease to the first preset difference value within a preset number of consecutive cooling cycles, it is determined that the frost blockage fault in the return air duct has been eliminated, and the refrigerator continues to operate the normal cooling and damper control logic.

[0165] In this embodiment of the application, when it is determined that there is a frost blockage fault in the return air duct, the defrosting program is started. After the defrosting program is fully executed and the frost in the duct is fully melted and discharged, the controller controls the compressor to restart, and the refrigerator enters the normal cooling operation state again, and the air circulation of the freezer cavity and the refrigerator cavity is restored synchronously.

[0166] After the compressor starts cooling, the controller continuously collects the first temperature and the second temperature and calculates the temperature difference deviation value in real time. It continuously tracks the parameter changes within a preset number of cooling cycles and determines whether the temperature difference deviation value is less than the first preset difference value throughout the entire process. For example, the preset number of cooling cycles can be 3, and the first preset difference value can be -1.5℃, which is used as the judgment criterion.

[0167] If the temperature difference deviation remains less than -1.5℃ for three consecutive cooling cycles, it indicates that defrosting has not improved the issue of the refrigerator compartment being colder at the top and hotter at the bottom. The return air blockage is not the root cause of the problem, and the controller then determines that the air distribution in the main air duct is uneven. Secondly, if the temperature difference deviation no longer remains less than -1.5℃ for three consecutive cooling cycles, meaning the parameter returns to the normal range, it indicates that the frost buildup in the return air duct has been completely cleared, the fault has been successfully resolved, and the refrigerator requires no additional intervention. It should continue to operate stably according to the factory-set conventional cooling logic and damper opening and closing rules, while maintaining constant temperature monitoring.

[0168] After determining that the air distribution in the main air supply duct is uneven, the controller outputs a control signal to drive the stepper motor to adjust the rotation angle of the damper blades, change the direction of the cold air outflow in the duct, and make the cold air mainly send out from the gap below the damper, thereby increasing the airflow to the bottom of the refrigerator cavity, supplementing the cold air at the bottom, and improving the problem of large temperature difference between the top and bottom of the refrigerator cavity.

[0169] For example, the preset reference temperature difference is -2℃, the first preset difference is -1.5℃, and the continuous monitoring cooling cycle is 3 times. After defrosting is complete and the compressor restarts: Condition 1: During three consecutive cooling cycles, the measured temperature difference is always below -2℃, and the calculated temperature difference deviation is always less than -1.5℃. The controller determines that the air distribution is uneven and then adjusts the damper blade angle to guide the cold air downward.

[0170] Condition 2: After defrosting, the measured temperature difference gradually returns to the normal range. If the temperature difference deviation is greater than or equal to -1.5℃, it is determined that the return air frost blockage fault has been resolved, and the refrigerator continues to operate in its original working mode.

[0171] In this embodiment, a periodic review mechanism is added on the basis of defrosting repair. This mechanism can accurately distinguish between two similar faults: return air frost accumulation and uneven air distribution. Differentiated treatment methods are adopted to avoid unnecessary repeated defrosting that would increase energy consumption. Furthermore, the airflow distribution can be optimized by fine-tuning the damper angle, which can effectively improve the temperature uniformity of the refrigeration chamber and the overall reliability of the machine.

[0172] Reference Figure 9 , Figure 9 This is a fifth flowchart of a refrigerator control method provided in an embodiment of this application, which is executed by the refrigerator controller and includes, but is not limited to, steps S910 to S9240.

[0173] Step S910: Obtain the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor.

[0174] Step S920: Subtract the first preset temperature from the first temperature to obtain the first temperature difference, and subtract the second preset temperature from the second temperature to obtain the second temperature difference.

[0175] Step S930: Determine whether the first temperature difference is within the first preset temperature fluctuation range.

[0176] Step S940: If the first temperature difference is within the first preset temperature fluctuation range, determine whether the second temperature difference is within the second preset temperature fluctuation range.

[0177] In step S950, if the second temperature difference is within the second preset temperature fluctuation range, the refrigeration is determined to be normal.

[0178] Step S960: Detect whether the first temperature is greater than or equal to the first preset temperature.

[0179] In step S970, if the first temperature is greater than or equal to the first preset temperature, the damper is opened to deliver cold air to the refrigeration chamber.

[0180] Step S980: If the first temperature is less than the first preset temperature, then detect whether the first temperature is less than or equal to the third preset temperature.

[0181] In step S990, if the first temperature is less than or equal to the second preset temperature, the damper is closed to stop supplying cold air to the refrigeration chamber. The first preset temperature is greater than the third preset temperature. If the first temperature is greater than the third preset temperature, the process returns to step S960.

[0182] In step S9100, if the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, then the refrigeration is determined to be abnormal.

[0183] Step S9110: Subtract the second temperature from the first temperature to obtain the measured temperature difference between the top and bottom of the refrigeration chamber.

[0184] Step S9120: Subtract the preset reference temperature difference from the measured temperature difference to obtain the temperature difference deviation value.

[0185] Step S9130: Determine whether the temperature difference deviation value is greater than the second preset difference value.

[0186] Step S9140: If the temperature difference deviation value is greater than the second preset difference value, determine whether the duration of the working condition where the temperature difference deviation value is greater than the second preset difference value is greater than or equal to the second preset duration; if the temperature difference deviation value is less than or equal to the second preset difference value, return to step S9130.

[0187] Step S9150: If the duration of the condition where the temperature difference deviation value is greater than the second preset difference value is greater than or equal to the second preset duration, then the fault type is determined to be at least one of the following: abnormal mechanical positioning of the damper, damper icing and jamming, and frost accumulation and blockage of the main air supply duct.

[0188] In step S9160, the damper blades are controlled to reset and calibrate throughout their full stroke, and the reference operating position of the stepper motor is recalibrated to perform damper reset.

[0189] Step S9170: Detect whether the temperature difference deviation value continues to be greater than the second preset difference value within the third preset time period after the damper reset is completed.

[0190] In step S9180, if the temperature difference deviation value continues to be greater than the second preset difference value within the third preset time period after the damper reset is completed, the damper is controlled to close and the heating element is turned on to heat the damper.

[0191] Step S9190: Determine whether the heating time of the heating element has reached the fourth preset time.

[0192] In step S9200, if the heating time of the heating element reaches the fourth preset time, control the heating element to be turned off and control the damper to be reopened; if the heating time of the heating element does not reach the fourth preset time, return to step S9190.

[0193] Step S9210: Determine whether the temperature difference deviation value continues to be greater than the second preset difference value within the fifth preset time period after the damper is opened.

[0194] In step S9220, if the temperature difference deviation value continues to be greater than the second preset difference value within the fifth preset time after the damper is opened, the defrosting program is started and the heating element is turned on to heat the damper.

[0195] Step S9230: Repeat the defrosting procedure according to the preset cycle until the temperature difference deviation value is within the preset normal temperature difference range, then control to stop the periodic defrosting and turn off the heating element.

[0196] In step S9240, if the temperature difference deviation value does not continuously exceed the second preset difference value within the third preset time period after the damper is reset, or if the temperature difference deviation value does not continuously exceed the second preset difference value within the fifth preset time period after the damper is opened, then the fault is determined to be eliminated, and the refrigerator continues to operate in its original working mode.

[0197] In this embodiment of the application, the phenomenon of the upper part being hot and the lower part being cold in the refrigeration chamber is mainly caused by abnormal mechanical positioning of the damper, icing and jamming of the damper, or frost blockage of the main air supply duct, which leads to abnormal air supply angle and air supply speed. As a result, the cold air cannot be delivered to the upper part of the refrigeration chamber normally, the upper area has insufficient cold supply and the temperature is too high, while the lower part has sufficient cold supply, ultimately resulting in the problem of the upper part being hot and the lower part being cold in the refrigeration chamber.

[0198] Specifically, the damper is mechanically positioned by a stepper motor, transmission mechanism, and limit structure. The controller outputs the corresponding number of pulse steps to fix the damper blades at the upward angle, so that the cold air is directionally delivered to the upper part of the refrigerator compartment. At this time, the air duct flow area is the largest and the air supply speed is stable. When mechanical positioning abnormalities such as gear wear, shaft loosening, limit failure, or motor step loss occur, the damper blades cannot reach the preset upward position and remain in a lower obstructed position. On the one hand, the air outlet faces downward, causing the air supply angle to deviate, and the mainstream cold air blows directly to the lower part of the refrigerator compartment, lacking a directionally upward cold airflow. On the other hand, the blades obstruct the air duct, reducing the effective ventilation cross section, increasing wind resistance, decreasing the overall air supply speed, and reducing the amount of cold air delivered per unit time. Only a small amount of cold air diffuses upward by weak natural convection. The upper part of the refrigerator compartment is chronically under-cooled, and the heat cannot be dissipated in time, ultimately resulting in a phenomenon where the upper part of the refrigerator compartment is hot and the lower part is cold.

[0199] Ice buildup around the damper blades and housing directly locks the blades' rotation, creating additional mechanical resistance. The stepper motor, hindered by the ice, exceeds its load limit and skips steps, failing to complete all the pulse steps issued by the controller. The blades remain in a lower, non-target position. This phenomenon is directly caused by ice jamming, unlike inherent damper mechanical positioning abnormalities such as gear wear or limit switch failure. Ice jamming prevents the blades from rising to the standard angle aligned with the upper air duct of the refrigerator compartment, causing a deviation in airflow direction. The main cold air flows directly to the lower part of the refrigerator compartment. Simultaneously, the blades are fixed in a semi-obstructed state by the ice, reducing the effective ventilation cross-section of the air duct, increasing airflow resistance, and consequently reducing the airflow velocity. Only a small amount of cold air slowly spreads upwards through natural convection. The upper part of the refrigerator compartment cannot obtain sufficient directional cooling to remove accumulated heat, resulting in an imbalance of upper-heat and lower-cooling conditions after long-term operation.

[0200] When thick frost accumulates on the inner wall of the main air duct, forming a frost blockage, the effective ventilation cross-sectional area inside the duct is significantly reduced, and the airflow resistance increases significantly. The overall flow velocity and airflow speed of the cold air delivered by the fan decrease simultaneously. At the same time, the frost layer changes the airflow direction inside the duct. The airflow channel that was originally directed to the upper part of the refrigerator cavity is squeezed by the frost, and the guiding path is deformed. Most of the cold air can only flow along the narrow space at the bottom of the duct and blow directly to the bottom of the refrigerator cavity, making it difficult to deliver it upward to the upper part of the refrigerator cavity. Only a small amount of cold air diffuses upward by weak natural convection. The upper part of the refrigerator cavity cannot obtain sufficient cold energy for continuous heat exchange and dissipation. The cold energy supply is insufficient for a long time, which eventually causes the problem of the upper part being hot and the lower part being cold with sufficient cold energy. This fault is caused by frost blockage in the duct and is a different fault cause from the icing and jamming of the damper or abnormal mechanical positioning of the damper.

[0201] After the controller determines that the refrigeration condition is abnormal, it immediately enters the refrigerator cavity temperature difference analysis and fault identification process. Specifically, the controller retrieves the first temperature at the top of the refrigerator cavity and the second temperature at the bottom. By subtracting the second temperature from the first temperature, the measured temperature difference between the top and bottom of the refrigerator cavity is obtained, which directly reflects the temperature stratification state within the cavity. For example, if the detected first temperature at the top of the refrigerator cavity is 4°C and the second temperature at the bottom is 2°C, then the measured temperature difference is 2°C.

[0202] Next, the controller subtracts the preset reference temperature difference from the calculated measured temperature difference to obtain the final temperature difference deviation value. For example, if the preset reference temperature difference is set to -2℃, the temperature difference deviation value is 4℃ based on the above measured temperature difference calculation. This parameter can intuitively reflect the degree of deviation between the actual temperature difference in the refrigeration cavity and the standard temperature difference, and is used to identify faults in the air damper and air supply duct.

[0203] The controller determines whether the current temperature difference deviation is greater than a second preset difference. For example, the second preset difference is set to 1.5℃, which serves as the threshold for judging faults in the upper heating and lower cooling of the refrigeration chamber, the damper, and the air supply duct. Using the data from the previous step, the current temperature difference deviation of 2℃ is greater than the second preset difference of 1.5℃, so the process proceeds to the next timing judgment stage; if the temperature difference deviation is less than or equal to the second preset difference, it indicates that the current temperature stratification is within the normal deviation range and no target fault characteristics have appeared, and the process returns to step S9130 for continuous cyclic monitoring.

[0204] When the temperature difference deviation exceeds a second preset value, the controller starts timing to determine whether the duration of the abnormal condition has reached or exceeded the second preset duration. For example, the preset reference temperature difference can be -2℃, the second preset difference can be +1.5℃, and the second preset duration can be 40 minutes. If the abnormal duration does not meet the standard, it indicates only a short-term temperature fluctuation, and the process returns to step S9140 to continue monitoring and timing.

[0205] When the temperature difference deviation exceeds the second preset value for a duration greater than or equal to the second preset duration, the controller determines the fault to be at least one of the following: abnormal mechanical positioning of the damper, damper icing and jamming, or frost accumulation and blockage in the main air supply duct. This type of fault will cause insufficient air intake at the top of the refrigerator compartment and a lower temperature at the bottom, ultimately resulting in a larger measured temperature difference between the top and bottom and a persistently high temperature difference deviation.

[0206] In response, the controller first drives the damper blades, which are driven by a stepper motor, to complete the full-stroke reciprocating motion, resetting the blade opening and closing angle and the guide position. At the same time, it recalibrates the reference operating position of the stepper motor, corrects the mechanical offset caused by long-term operation of the equipment, and prioritizes solving the problem of inaccurate damper positioning.

[0207] After the damper is reset, the controller continuously monitors the temperature difference deviation value for a third preset time period. For example, the third preset time period can be set to 40 minutes, and the controller will determine whether the temperature difference deviation value is continuously greater than the second preset difference value throughout the process.

[0208] If the temperature difference deviation value continues to be greater than the second preset difference value within the third preset time period, it indicates that the damper reset has not eliminated the fault. The controller controls the damper blades to close and activates the integrated heating element of the damper to melt the frost and release the jam using a local heat source. If the temperature difference deviation value no longer continues to be greater than the second preset difference value within the third preset time period, it is determined that the fault has been eliminated, the refrigerator exits the repair process, and maintains normal cooling, temperature monitoring, and damper control logic operation.

[0209] After the heating element is turned on, the controller monitors the heating element's operating time in real time and determines whether the fourth preset time has been reached. For example, the fourth preset time can be set to 60 minutes. If the heating element's operating time has not reached the fourth preset time, the heating state continues, and the process returns to step S9180; if the heating element's operating time has reached the fourth preset time, the controller turns off the heating element and simultaneously reopens the damper to restore the cold air delivery to the main air duct, proceeding to the next stage of operating condition verification.

[0210] After the damper is reopened, the controller continuously monitors the temperature difference deviation value within a fifth preset time period. For example, the fifth preset time period can be set to 30 minutes to determine whether the temperature difference deviation value is continuously greater than the second preset difference value during this period.

[0211] If the temperature difference deviation value no longer exceeds the second preset value within the fifth preset time period, it is determined that all problems such as frost, jamming, and positioning abnormalities have been eliminated, the fault repair is complete, and the whole machine returns to normal operation mode. However, if the temperature difference deviation value continues to exceed the second preset value within the fifth preset time period, it indicates that local heating of the damper alone cannot completely remove the accumulated ice and frost. In this case, the controller starts the whole machine defrosting program and keeps the damper heating element continuously open.

[0212] The controller repeats the defrosting program according to the preset cycle, continuously removing stubborn frost from the main air supply duct and dampers; until the temperature difference deviation value returns to the preset normal temperature difference range, confirming that the cooling and air supply status has been fully restored, the controller stops the periodic defrosting and turns off the damper heating element, and the entire fault repair process ends.

[0213] For example, the preset reference temperature difference is -2℃, the second preset difference is 1.5℃, the second preset duration is 40 minutes, the third preset duration is 40 minutes, the fourth preset duration is 60 minutes, and the fifth preset duration is 30 minutes.

[0214] Condition 1: Repair is successful once the damper is reset. After the cooling malfunction trigger procedure, the measured temperature difference is 2.0℃, and the temperature difference deviation is 4℃. If the temperature difference deviation is greater than the second preset deviation of 1.5℃ for 40 consecutive minutes, a damper / air duct malfunction is determined; a full-stroke damper reset calibration is performed. If the temperature difference deviation drops back to 1℃ (≤1.5℃) within 40 minutes after the reset, the malfunction is determined to be eliminated, and the refrigerator is operating normally.

[0215] Condition 2: Localized heating repair successful If the temperature difference deviation remains above 4℃ (consistently greater than 1.5℃) within 40 minutes after the damper resets, the controller closes the damper and activates the heating element. After 60 minutes of heating, the heating is turned off and the damper is opened. During the subsequent 30 minutes of monitoring, if the temperature difference deviation drops to 1℃ (≤1.5℃), the fault is determined to be resolved, and the entire machine resumes normal operation.

[0216] Condition 3: Periodic defrosting is required to complete the repair. After the damper is reset and local heating is initiated, the temperature difference deviation remains stable at 2℃ (consistently greater than 1.5℃) for 30 minutes after the damper is opened. The controller then initiates the defrosting program and keeps the heating element on, repeatedly defrosting at a fixed cycle until the temperature difference deviation enters the normal range, at which point defrosting stops and the heating element is turned off.

[0217] In this embodiment, a layered, progressive fault repair logic is adopted. First, the damper position deviation is corrected by mechanical reset. Then, minor icing and jamming are treated by local heating. Finally, the stubborn frost buildup in the air duct is resolved by periodic defrosting. This tiered approach avoids blindly initiating whole-machine defrosting, effectively reducing overall energy consumption. At the same time, relying on the temperature difference judgment method of dual temperature measuring points, hidden faults such as dampers and air ducts are accurately identified, significantly improving the uniformity of the refrigerator's cooling temperature and the long-term operational reliability of the entire unit.

[0218] Reference Figure 10 , Figure 10 This is a sixth flowchart of a refrigerator control method provided in an embodiment of this application, which is executed by the refrigerator controller and includes, but is not limited to, steps S1010 to S1040.

[0219] Step S1010: Obtain the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor.

[0220] In this step, the controller continuously acquires the first temperature collected by the first temperature sensor at the top of the refrigeration chamber and the second temperature collected by the second temperature sensor at the bottom of the refrigeration chamber, providing basic data for low temperature determination.

[0221] Step S1020: Determine whether the first temperature is less than the preset low temperature threshold.

[0222] In this step, the controller compares the first temperature with a preset low-temperature threshold to determine whether the first temperature is lower than the preset low-temperature threshold. For example, the preset low-temperature threshold can be set to 0.5℃.

[0223] Step S1030: If the first temperature is not less than the preset low temperature threshold, then determine whether the second temperature is less than the preset low temperature threshold.

[0224] In this step, if the first temperature is determined to be not less than the preset low temperature threshold, it means that the temperature at the top of the refrigerator cavity is in the normal range. The controller then continues to determine the second temperature and detects whether the temperature at the bottom of the refrigerator cavity is lower than the preset low temperature threshold.

[0225] In step S1040, if the first temperature is less than the preset low temperature threshold, or the second temperature is less than the preset low temperature threshold, the defrosting program is started; if the second temperature is not less than the preset low temperature threshold, the process returns to step S1010.

[0226] In this step, as long as either the first temperature or the second temperature is less than the preset low-temperature threshold, the controller immediately initiates the defrosting program. The heating components melt the ice and frost, preventing blockages or clogging of the air vents and ducts due to ice buildup at low temperatures. If the second temperature is also not less than the preset low-temperature threshold, it indicates that the temperature throughout the refrigeration chamber is within a safe range, with no risk of ultra-low temperatures or frost formation. The process then returns to step S1010 to continue cyclically collecting and monitoring the temperature.

[0227] For example, the preset low temperature threshold is set to 0.5°C.

[0228] Defrosting Trigger Conditions: When the first temperature is 0.3℃, which is less than 0.5℃, the controller directly starts the defrosting program; or when the first temperature is 1.2℃ and the second temperature is 0.4℃ (bottom temperature is below 0.5℃), the defrosting program is also triggered.

[0229] Normal operating conditions: The first temperature is 1.5℃, the second temperature is 1.1℃, and both temperatures are not less than 0.5℃. The controller does not perform defrosting action, and the process returns to step S1010 to continuously monitor the temperature.

[0230] In this embodiment, a step-by-step comparison method is adopted, and low-temperature protection of the entire cold storage cavity is achieved by relying on dual-point temperature monitoring. This can promptly address local ultra-low temperature problems, resolve potential malfunctions in the air supply system in advance, and initiate defrosting only when necessary, reducing ineffective operations and balancing equipment reliability with overall energy consumption control.

[0231] It is understood that those skilled in the art can make equivalent substitutions or changes to the technical solution and inventive concept of the present invention, and all such changes or substitutions should fall within the protection scope of the present invention.

Claims

1. A method for controlling a refrigerator, characterized in that, The refrigerator includes: The box contains a refrigeration chamber and a freezing chamber. A refrigeration system, comprising a compressor, a condenser, a capillary tube, and an evaporator connected in series to form a loop; An air supply system, comprising a fan, a main air supply duct, dampers, and a return air duct; The freezer chamber is equipped with an evaporator air duct compartment. The evaporator and the fan are both installed in the evaporator air duct compartment. The evaporator air duct compartment is provided with a communication port to communicate with the storage space of the freezer chamber. One end of the main air supply duct is connected to the evaporator air duct compartment, and the other end of the main air supply duct is connected to the top of the refrigerator compartment. The main air supply duct is used to transport the cold air generated by the evaporator to the refrigerator compartment. The damper is located inside the main air supply duct, and the damper is used to adjust the amount and direction of cold air flowing into the refrigeration chamber in the main air supply duct. One end of the return air duct is connected to the return air inlet at the bottom of the refrigeration chamber, and the other end of the return air duct flows back into the evaporator air duct compartment. The temperature detection assembly includes a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is disposed at the top of the refrigeration cavity and the second temperature sensor is disposed at the bottom of the refrigeration cavity; The control method includes: Acquire the first temperature collected by the first temperature sensor and the second temperature collected by the second temperature sensor; The first temperature difference is obtained by subtracting the first preset temperature from the first temperature, and the second temperature difference is obtained by subtracting the second preset temperature from the second temperature. When the first temperature difference is within the first preset temperature fluctuation range and the second temperature difference is within the second preset temperature fluctuation range, the cooling is determined to be normal. When the first temperature difference exceeds the first preset temperature fluctuation range, or the second temperature difference exceeds the second preset temperature fluctuation range, the refrigeration is determined to be abnormal. After determining that the refrigeration is abnormal, the first temperature is subtracted from the second temperature to obtain the measured temperature difference between the top and bottom of the refrigeration cavity; The temperature difference deviation value is obtained by subtracting the preset reference temperature difference from the measured temperature difference. The temperature difference deviation value is compared with a first preset difference value; If the temperature difference deviation value is less than the first preset difference value and the condition continues for a first preset time, it is determined that there is a frost accumulation blockage fault in the return air duct. Control the start of the defrosting procedure to melt the frost accumulated in the return air duct; After the defrosting process is completed and the refrigerator resumes cooling operation, if the temperature difference deviation value is continuously less than the first preset difference value within a preset number of consecutive cooling cycles, it is determined that the air distribution in the main air duct is uneven. The rotation angle of the damper blades is controlled and adjusted so that cold air flows out from the gap below the damper, thereby increasing the airflow delivered to the bottom of the refrigeration chamber.

2. The method according to claim 1, characterized in that, After determining that the cooling is normal, the method further includes: The damper is opened or closed based on the first temperature collected by the first temperature sensor.

3. The method according to claim 2, characterized in that, The step of controlling the opening and closing of the damper based on the first temperature collected by the first temperature sensor includes: When the first temperature is detected to be greater than or equal to the first preset temperature, the damper is controlled to open to deliver cold air to the refrigeration chamber. When the first temperature is detected to be less than or equal to the third preset temperature, the damper is controlled to close to stop supplying cold air to the refrigeration chamber. The first preset temperature is greater than the third preset temperature.

4. The method according to claim 2 or 3, characterized in that, After controlling the damper to open, the method further includes: The timing is started in response to the opening action of the damper, and the second temperature collected by the second temperature sensor is acquired at preset time intervals; If the second temperature does not decrease when the cumulative time reaches the first set time, it is determined that the air volume of the main air supply duct is insufficient. Increase the speed of the fan to increase the air volume supplied by the main air duct.

5. The method according to claim 1, characterized in that, After determining that the cooling is abnormal, the method further includes: The measured temperature difference between the top and bottom of the refrigeration cavity is obtained by subtracting the second temperature from the first temperature. The temperature difference deviation value is obtained by subtracting the preset reference temperature difference from the measured temperature difference. The temperature difference deviation value is compared with the second preset difference value; If the temperature difference deviation value is greater than the second preset difference value and the condition continues for the second preset time, the fault type is determined to be at least one of the following: abnormal mechanical positioning of the damper, damper icing and jamming, and frost accumulation and blockage of the main air supply duct.

6. The method according to claim 5, characterized in that, The damper is driven by a stepper motor and controls the opening and closing angle of the blades and the guide position by a preset number of steps. The damper integrates a heating element. After determining that the fault type is at least one of the following: abnormal mechanical positioning of the damper, damper icing and jamming, and frost accumulation and blockage of the main air supply duct, the method further includes: The damper blades are controlled to reset and calibrate throughout their full stroke, and the reference operating position of the stepper motor is recalibrated to perform damper reset. If the temperature difference deviation value continues to be greater than the second preset difference value within the third preset time period after the damper reset is completed, the damper is controlled to close and the heating element is turned on to heat the damper. When the heating time for the heating element to heat the damper reaches the fourth preset time, the heating element is controlled to be turned off and the damper is controlled to be reopened. If the temperature difference deviation value continues to be greater than the second preset difference value within the fifth preset time period after the damper is opened, the defrosting program is started and the heating element is turned on to heat the damper. The defrosting procedure is repeated according to a preset cycle until the temperature difference deviation value is within the preset normal temperature difference range, at which point the periodic defrosting is stopped and the heating element is turned off.

7. The method according to claim 1, characterized in that, The method further includes: During the operation of the refrigerator, when the first temperature or the second temperature is detected to be lower than the preset low temperature threshold, the defrosting program is initiated.

8. A refrigerator, characterized in that, The refrigerator includes: The box contains a refrigeration chamber and a freezing chamber. A refrigeration system, comprising a compressor, a condenser, a capillary tube, and an evaporator connected in series to form a loop; An air supply system, comprising a fan, a main air supply duct, dampers, and a return air duct; The freezer chamber is equipped with an evaporator air duct compartment. The evaporator and the fan are both installed in the evaporator air duct compartment. The evaporator air duct compartment is provided with a communication port to communicate with the storage space of the freezer chamber. One end of the main air supply duct is connected to the evaporator air duct compartment, and the other end of the main air supply duct is connected to the top of the refrigerator compartment. The main air supply duct is used to unidirectionally transport the cold air circulated in the freezer compartment to the refrigerator compartment. The damper is located inside the main air supply duct, and the damper is used to adjust the amount and direction of cold air flowing into the refrigeration chamber in the main air supply duct. One end of the return air duct is connected to the return air inlet at the bottom of the refrigeration chamber, and the other end of the return air duct flows back into the evaporator air duct compartment. The temperature detection assembly includes a first temperature sensor and a second temperature sensor, wherein the first temperature sensor is disposed at the top of the refrigeration cavity and the second temperature sensor is disposed at the bottom of the refrigeration cavity; A controller, which is electrically connected to the fan, the damper, the first temperature sensor and the second temperature sensor respectively, and is used to perform the method according to any one of claims 1 to 7.

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