Refrigerator and defrosting control method therefor

Abstract

Disclosed in some embodiments of the present application are a refrigerator and a defrosting control method therefor. The refrigerator comprises a refrigerator body; a refrigeration system, which is configured to provide cold for the refrigerator, wherein the refrigeration system comprises a compressor, a condenser and an evaporator connected in sequence by means of a pipe; a switching valve, which is disposed in the refrigeration system and is configured to switch a flow direction of a refrigerant in the refrigeration system, wherein the flow direction of the refrigerant comprises a first flow direction during the operation in a refrigeration mode and a second flow direction during the operation in a defrosting mode; and a controller. The controller is configured to: when it is detected that the refrigerator enters the defrosting mode, control the compressor to shut down and record a first shutdown duration of the compressor; when the first shutdown duration is greater than a preset first duration threshold, adjust the switching valve to switch the flow direction of the refrigerant from the first flow direction to the second flow direction, and record a waiting duration after the switching valve has been adjusted; and when the waiting duration is greater than a preset second duration threshold, control the compressor to start.

Description

Refrigerators and their defrosting control methods

[0001] Related applications

[0002] This application claims priority to Chinese patent application No. 2025102063179, filed on February 24, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of electrical equipment technology, and in particular to a refrigerator and a defrosting control method thereof. Background Technology

[0004] The evaporator of a refrigerator is fixed inside the refrigerator liner. Frost will form on the evaporator during cooling, and this frost layer negatively impacts heat exchange. When the frost layer accumulates to a certain extent, it will affect the refrigerator's cooling performance, thus requiring defrosting. Defrosting can consume electricity and cause wear and tear on components such as the compressor. Therefore, how to achieve defrosting while simultaneously saving energy and protecting components like the compressor is a significant concern. Summary of the Invention

[0005] This application provides a refrigerator and a defrosting control method thereof in some embodiments, which reduces energy consumption and wear on the compressor while achieving defrosting.

[0006] In a first aspect, some embodiments of this application provide a refrigerator, including:

[0007] Box;

[0008] A refrigeration system configured to provide cooling capacity to a refrigerator, the refrigeration system comprising a compressor, a condenser, and an evaporator connected in sequence by pipes;

[0009] A switching valve, located in the refrigeration system, is configured to switch the flow direction of the refrigerant in the refrigeration system; wherein the flow direction of the refrigerant includes a first flow direction operating in refrigeration mode and a second flow direction operating in defrost mode;

[0010] The controller is configured to:

[0011] When the refrigerator is detected to have entered defrost mode, the compressor is controlled to stop, and the first shutdown duration of the compressor is recorded.

[0012] When the first shutdown duration exceeds a preset first duration threshold, the switching valve is adjusted to switch the refrigerant flow direction from the first flow direction to the second flow direction, and the waiting time of the switching valve after adjustment is recorded.

[0013] When the waiting time exceeds a preset second time threshold, the compressor is controlled to start.

[0014] By setting a first time threshold, when the refrigerator enters defrost mode, the compressor is allowed to stop for a certain period before subsequent operations are performed, preventing the compressor from starting frequently in a short period. When the first stop time exceeds the first time threshold, the switching valve is adjusted. At this point, system parameters such as pressure are more stable, and the load on the subsequent compressor startup is relatively small, which is conducive to a smooth compressor start-up and reduces the impact on the compressor and the entire refrigeration system. When the waiting time after the switching valve adjustment exceeds a second time threshold, the compressor is started. This ensures that after the switching valve action, the system has sufficient time for pressure balancing and state stabilization, avoiding problems such as refrigerant flow disturbances caused by premature compressor startup, resulting in refrigerant waste or incomplete defrosting. Furthermore, this application avoids unnecessary compressor operation and ineffective refrigerant circulation, allowing the system to utilize energy more rationally during defrosting and cooling processes, reducing overall power consumption. In defrost mode, the compressor is only started after the switching valve is adjusted and the waiting time meets the requirements, optimizing the compressor startup time, avoiding energy waste, helping to achieve energy-saving goals, and reducing user operating costs.

[0015] Secondly, some embodiments of this application also provide a defrosting control method for a refrigerator, including:

[0016] When the refrigerator is detected to have entered defrost mode, the compressor is stopped and the first shutdown duration of the compressor is recorded.

[0017] When the first shutdown duration exceeds a preset first duration threshold, the switching valve is adjusted to switch the refrigerant flow direction from the first flow direction to the second flow direction, and the waiting time of the switching valve after adjustment is recorded; wherein, the switching valve is configured to change the refrigerant flow direction in the refrigeration system; the refrigerant flow direction includes the first flow direction when operating in refrigeration mode and the second flow direction when operating in defrost mode;

[0018] When the waiting time exceeds a preset second time threshold, the compressor is controlled to start.

[0019] The refrigerator and defrosting control method provided in some embodiments of this application, by setting a first time threshold, allows the compressor to stop for a certain period of time before proceeding with subsequent operations when the refrigerator enters defrosting mode, preventing the compressor from starting frequently in a short period of time. When the first stop time exceeds the first time threshold, the switching valve is adjusted. At this time, the pressure and other parameters in the system are more stable, and the load on the compressor when it starts is relatively small, which is conducive to a smooth start-up of the compressor and reduces the impact on the compressor and the entire refrigeration system during startup. When the waiting time after the switching valve adjustment exceeds a second time threshold, the compressor is started. This ensures that after the switching valve action is completed, the system has sufficient time for pressure balancing and state stabilization, avoiding problems such as refrigerant flow disturbances caused by premature compressor startup, resulting in refrigerant waste or incomplete defrosting. Furthermore, the control logic provided in this application avoids unnecessary compressor operation and ineffective refrigerant circulation, enabling the system to utilize energy more rationally during defrosting and cooling processes, reducing overall power consumption. In defrost mode, the compressor is only started after the switching valve is adjusted and the waiting time meets the requirements. This optimizes the compressor start-up time, avoids energy waste, helps achieve energy-saving goals, and reduces user operating costs.

[0020] Details of one or more embodiments of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the published drawings without creative effort.

[0022] Figure 1 is a schematic diagram of the external structure of a refrigerator according to some embodiments.

[0023] Figure 2 is a schematic diagram of the internal structure of a refrigerator according to some embodiments.

[0024] Figure 3 is a schematic diagram of the structure of a refrigeration system according to some embodiments.

[0025] Figure 4 is a schematic diagram of the structure of a refrigeration system according to some other embodiments.

[0026] Figure 5 is a schematic diagram of the refrigerant flow in the defrosting mode of a refrigeration system according to some other embodiments.

[0027] Figure 6 is a schematic diagram of the refrigerant flow direction in the refrigeration mode of the refrigeration system shown in the embodiment of Figure 5.

[0028] Figure 7 is a structural block diagram of a refrigerator according to some embodiments.

[0029] Figure 8 is a flowchart of the controller in defrost mode according to some embodiments.

[0030] Figure 9 is a flowchart of the controller in cooling mode according to some embodiments.

[0031] Figure 10 is a schematic diagram of the switching valve according to some embodiments.

[0032] Figure 11 is a schematic diagram of the operation of the switching valve shown in Figure 10.

[0033] Figure 12 is a schematic diagram of another switching valve according to some embodiments.

[0034] Figure 13 is a schematic diagram of the connection of the switching valve shown in Figure 12 in cooling mode according to some embodiments.

[0035] Figure 14 is a schematic diagram of the connection of the switching valve shown in Figure 12 in defrosting mode according to some embodiments.

[0036] Figure 15 is a flowchart of a defrosting control method for a refrigerator according to some embodiments. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0038] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0039] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0040] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0041] When a refrigerator is cooling, frost will form on the evaporator. When the frost accumulates to a certain level, it will affect the refrigerator's cooling performance. Some technologies use a heating device on the evaporator to defrost, but this increases energy consumption. Other technologies use a refrigerant reversal system, allowing the evaporator to function as a condenser, thus defrosting by releasing heat from the evaporator. However, the inventors discovered that in refrigerant reversal defrosting technology, directly switching operating modes (such as from cooling to defrosting mode, or vice versa) can cause the system to suddenly change between high and low pressure, leading to excessively high compressor suction pressure. This can exceed the compressor's reliable operating range, causing compressor failure and affecting its lifespan.

[0042] Based on this, this application provides a refrigerator and a defrosting control method.

[0043] Referring to Figure 1, which is a schematic diagram of the external structure of a refrigerator 100 according to some embodiments of this application, the refrigerator 100 has an approximately cuboid shape and includes a cabinet defining a storage space and one or more doors disposed at the opening of the cabinet. The doors include a door shell located outside the cabinet, a door inner liner located inside the cabinet, an upper end cover, a lower end cover, and an insulation layer located between the door shell, the door inner liner, the upper end cover, and the lower end cover. Typically, the insulation layer is filled with foam material. The cabinet has chambers, including component storage chambers configured to house components of the refrigerator, such as a compressor compartment, and storage spaces configured to store food, etc.

[0044] Referring to Figure 2, which is a schematic diagram of the internal structure of a refrigerator according to some embodiments of this application, the storage space can be divided into multiple storage compartments. Depending on their purpose, these compartments can be configured as a refrigerator compartment 101 and a freezer compartment 102, and may also include a variable temperature compartment, a vacuum drawer, a humidifier drawer, etc. Each storage compartment corresponds to one or more doors; for example, in Figure 2, the upper storage compartment has double doors. The doors can be pivotally mounted at the opening of the refrigerator body. In some embodiments, the storage compartments may also be equipped with drawers, which can be opened and closed by pushing or pulling them out.

[0045] Referring to Figure 3, which is a schematic diagram of a first refrigeration system provided in some embodiments of this application, the refrigeration system is configured to provide cooling capacity to a refrigerator. The refrigeration system includes a compressor 1, a condenser 2, and an evaporator 3 connected in sequence by pipes. The compressor 1, condenser 2, and evaporator 3 form a refrigerant circulation loop.

[0046] The refrigeration system also includes a switching valve 4. The switching valve 4 is connected in the refrigerant circulation loop and is configured to change the flow direction of the refrigerant in the refrigeration system. The refrigerant flow direction includes a first flow direction operating in refrigeration mode and a second flow direction operating in defrost mode. In the first and second flow directions, the refrigerant flows in opposite directions between the compressor, evaporator, and condenser. In the embodiment shown in Figure 3, the switching valve 4 may be, for example, a four-way valve.

[0047] The refrigeration system also includes a receiver 5. In some embodiments, the receiver 5 is connected between the compressor 1 and the switching valve 4. During the operation of the refrigerator refrigeration system, the refrigerant flow rate changes according to different operating conditions and refrigeration demands. The receiver 5 can store a certain amount of refrigerant. When the system load is high and more refrigerant is needed for circulation, it can replenish the system in a timely manner. When the system load is low, the receiver 5 can store excess refrigerant, ensuring that the amount of refrigerant in the system is always within a suitable range, maintaining the stable operation of the refrigeration system. In addition, the refrigerant coming out of the evaporator 3 is usually in a gas-liquid mixed state. If this gas-liquid mixed refrigerant directly enters the compressor 1, it may cause liquid slugging in the compressor 1, damaging the compressor. The receiver 5 can act as a gas-liquid separator, allowing the gaseous refrigerant to preferentially enter the compressor 1, while the liquid refrigerant is temporarily stored in the receiver 5 and enters the system circulation at a suitable time, thereby protecting the compressor 1, extending its service life, and ensuring the safe operation of the refrigeration system.

[0048] For example, some embodiments of this application employ counter-current defrosting technology. When the refrigerator is operating in cooling mode, the refrigerant flows in a first direction: compressor 1 → switching valve 4 → condenser 2 → evaporator 3 → switching valve 4 → receiver 5 → compressor 1. When the refrigerator is operating in defrosting mode, the refrigerant flows in a second direction: compressor 1 → switching valve 4 → evaporator 3 → condenser 2 → switching valve 4 → receiver 5 → compressor 1.

[0049] It should be noted that the working process of the refrigerator's cooling mode and the defrosting mode using counter-current defrosting technology can be referred to the relevant technologies in this field, and will not be described in detail here.

[0050] Referring to Figure 4, which is a schematic diagram of the structure of a second refrigeration system provided in some embodiments of this application, the refrigerator also includes a decondensation component 10.

[0051] The decondensation assembly 10 includes a condensate evaporation pipe 11, configured to evaporate condensate generated inside the refrigerator. The decondensation assembly 10 also includes a decondensation pipe 12, with the condensate evaporation pipe 11 located between the compressor 1 and the decondensation pipe 12, and connected to the air outlet of the compressor 1. The decondensation pipe 12 is located between the condensate evaporation pipe 11 and the switching valve 4.

[0052] In some embodiments of this application, the condensate evaporator pipe 11 is connected to the outlet of the compressor 1. When the high-temperature, high-pressure refrigerant gas discharged from the compressor 1 flows through the condensate evaporator pipe 11, it transfers heat to the condensate evaporator pipe 11. This heat, which might otherwise be wasted, is used to evaporate the condensate generated inside the refrigerator, achieving heat recovery and improving the overall energy efficiency of the refrigerator. By using the decondensation component to evaporate the condensate and regulate the refrigerator surface temperature, additional heat exchange losses due to condensation on the refrigerator surface are reduced. Without the decondensation component, condensation on the refrigerator surface absorbs heat from the surrounding environment, requiring the refrigeration system to consume more energy to maintain the low temperature inside the refrigerator. The presence of the decondensation component reduces this additional heat load, thereby reducing the burden on the refrigeration system, lowering energy consumption, and contributing to energy-efficient operation of the refrigerator.

[0053] Referring to Figures 5 and 6, Figure 5 is a schematic diagram of the refrigerant flow in the defrosting mode of a third refrigeration system provided in some embodiments of this application, and Figure 6 is a schematic diagram of the refrigerant flow in the refrigeration mode of a third refrigeration system provided in some embodiments of this application. In some embodiments, as shown in Figures 5 and 6, the refrigerator further includes a first branch 20 disposed between the switching valve 4 and the evaporator 3. The first branch 20 includes a first capillary tube 7. The first branch 20 also includes a first dryer filter 6 connected to the first capillary tube 7. The first end of the first capillary tube 7 is connected to the evaporator 3, the second end of the first capillary tube 7 is connected to the first end of the first dryer filter 6, and the second end of the first dryer filter 6 is connected to the switching valve 4.

[0054] The refrigerator also includes a second branch 30, located between the switching valve 4 and the evaporator 3. The second branch 30 includes a second capillary tube 8. The second branch 30 also includes a second dryer filter 9 connected to the second capillary tube 8. The first end of the second capillary tube 8 is connected to the switching valve 4, and the second end of the second capillary tube 8 is connected to the first end of the second dryer filter 9. The second end of the second dryer filter 9 is connected to the evaporator 3.

[0055] For example, the switching valve 4 includes seven ports, numbered 41 to 47. The fixed connection method (unchangeable) of the switching valve 4 is as follows: port 46 is connected to the compressor outlet, port 44 is connected to the liquid receiver 5, ports 47 and 41 are connected to the condenser 2 respectively, port 42 is connected to the second branch, port 43 is connected to the first branch, and port 45 is connected to the evaporator 3. The ports of the switching valve 4 can be dynamically connected to each other. This dynamic connection method includes a first connection method corresponding to the cooling mode and a second connection method corresponding to the defrosting mode. The detailed process of the dynamic connection method for different operating modes is as follows:

[0056] 1) Defrosting mode, see Figure 5. When the refrigeration system is running in the defrosting mode, the refrigerant flows out of the evaporator 3 and flows sequentially through the second dryer filter 9, the second capillary tube 8 and the switching valve 4.

[0057] For example, at this time, ports 41 and 42, ports 44 and 47, and ports 45 and 46 in switching valve 4 are connected, and the refrigerant flow direction is the second flow direction, including: compressor 1 → port 46 → port 45 → evaporator 3 → second dryer filter 9 → second capillary tube 8 → port 42 → port 41 → condenser 2 → port 47 → port 44 → receiver 5 → compressor 1. The second capillary tube 8 plays a throttling role in the second branch. In defrost mode, when the refrigerant passes through the second capillary tube 8, the pressure decreases, allowing the refrigerant to enter the evaporator 3 at a suitable pressure and state for defrosting. The second dryer filter 9 in the second branch can prevent impurities and moisture that may be generated during the defrosting process from damaging the evaporator 3. During defrosting, the frost layer on the surface of evaporator 3 melts to form water. If the water contains impurities or there is moisture in the system, it may cause adverse effects such as corrosion to evaporator 3. The second dryer filter 9 can filter impurities and absorb moisture, protect evaporator 3, extend the service life of evaporator 3, and ensure that evaporator 3 can work normally after defrosting without affecting the cooling effect.

[0058] 2) Cooling mode, see Figure 6. When the refrigeration system is running in the cooling mode, the refrigerant flows out from the switching valve 4 and flows sequentially through the first dryer filter 6, the first capillary tube 7 and the evaporator 3.

[0059] For example, at this time, ports 41 and 43, ports 46 and 47, and ports 44 and 45 in switching valve 4 are connected, and the refrigerant flow direction is the first direction, including: compressor 1 → port 46 → port 47 → condenser 2 → port 41 → port 43 → first dryer filter 6 → first capillary tube 7 → evaporator 3 → port 45 → port 44 → liquid receiver 5 → compressor 1. The first capillary tube 7 plays a key role in throttling and pressure reduction in the first branch. The refrigerant pressure is high before entering the evaporator 3. When passing through the first capillary tube 7, due to its small diameter, it forms resistance to the refrigerant, causing the refrigerant pressure to decrease, thereby achieving throttling and pressure reduction. This allows the refrigerant to evaporate and absorb heat under a suitable low pressure state in the evaporator 3, ensuring the cooling effect of the evaporator 3 and enabling the refrigerator interior to be effectively cooled. The main function of the first dryer filter 6 is to filter impurities in the refrigeration system. During the operation of the refrigeration system, some metal shavings, dust and other impurities may be generated. If these impurities enter the evaporator 3 or other components, they may clog pipes and wear parts, affecting the normal operation of the system. The first dryer filter 6 can effectively intercept these impurities, ensure the cleanliness of the refrigeration system and extend the service life of the system.

[0060] In some embodiments of this application, in the counter-current defrosting technology, the first branch and the second branch are independent of each other and do not share pipes. This allows the application of capillary tubes and dryer filters to better suit the refrigerator's operating mode, thereby improving defrosting and cooling efficiency. Furthermore, if the capillary tube in one branch is blocked, the capillary tube in the other branch can be used, avoiding the problem of the refrigeration system failing to operate normally (defrosting or cooling) due to blockage of one capillary tube, thus maintaining the normal operation of the refrigeration system.

[0061] In some embodiments, the flow rate of the second capillary 8 is greater than the flow rate of the first capillary 7.

[0062] In some embodiments of this application, the evaporator 3 and condenser 2 interchange functions when the refrigerant flows forward to achieve refrigeration and when it flows backward to achieve defrosting. Due to the large difference in the internal volume of the two evaporators, the high and low pressure matching in the two flow directions varies greatly. The system design provided in some embodiments of this application utilizes different capillary flow rates to adapt to different refrigeration cycle requirements. During defrosting, sufficient heat is needed to quickly melt the frost layer on the evaporator surface. The second branch capillary has a larger flow rate, allowing more high-temperature refrigerant to flow through the evaporator per unit time. More refrigerant means more heat is carried to the evaporator, thereby accelerating the melting speed of the frost layer, shortening the defrosting time, improving defrosting efficiency, and enabling the evaporator to recover to a good heat exchange state more quickly. Therefore, when the flow rate of the second capillary 8 is greater than that of the first capillary 7, it can adapt to the current requirement of a large flow rate in the second branch, thereby increasing the system evaporation temperature and improving the system's counter-current cycle efficiency.

[0063] In some embodiments, referring to FIG7, the refrigerator further includes a controller 40, which is connected to the compressor 1 and the switching valve 4. The controller 40 is configured to: when the refrigerator detects that it has entered the defrost mode, control the compressor to stop and record a first stop duration of the compressor; when the first stop duration is longer than a preset first duration threshold, adjust the switching valve to switch the refrigerant flow direction from a first flow direction to a second flow direction and record the waiting time of the switching valve after adjustment; when the waiting time is longer than a preset second duration threshold, control the compressor to start.

[0064] For example, see Figure 8, which is a flowchart of the controller in defrost mode provided in some embodiments of this application. The controller 30 is configured to perform steps S11 to 16.

[0065] Step S11: Determine if the refrigerator has entered defrost mode.

[0066] Step S12: When it is determined that the refrigerator has entered defrost mode, the controller controls the compressor to stop and records the first shutdown duration of the compressor. The first shutdown duration is the duration of the compressor shutdown.

[0067] Step S13: Determine whether the first downtime has reached the first duration threshold.

[0068] Step S14: After the compressor stops for the first time and the first time threshold is reached, control the switching valve to switch to the connection of ports 41 and 42, ports 44 and 47, and ports 45 and 46 in the switching valve 4. That is, the switching valve switches the flow direction of the refrigerant from the first flow direction to the second flow direction, and records the waiting time for the switching valve to maintain this state.

[0069] Step S15: Determine whether the waiting time has reached the second time threshold.

[0070] Step S16: After the waiting time reaches the second time threshold, control the compressor to start running.

[0071] This control design is primarily based on the following: When the refrigeration system is cooling, the compressor discharges into the condenser, which is the high-pressure side, typically with a pressure of 500–800 kPa. When the system needs to defrost, if the valve body switches to direct compressor operation, and the condenser component is switched to the low-pressure side, becoming the compressor's suction component, it will cause excessively high compressor suction pressure, leading to compressor valve plate breakage. If the first step of stopping the compressor and waiting for the system to self-balance is executed, the shutdown time before defrosting starts will be too long, causing the storage room temperature to rise and affecting the quality of food storage.

[0072] In some embodiments of this application, the system self-balancing problem is considered when the refrigerator is performing counter-current defrosting. By setting a first time threshold, the compressor is allowed to stop for a certain period of time after the refrigerator enters defrosting mode before subsequent operations are performed, preventing the compressor from starting frequently in a short period of time. When the first stop time exceeds the first time threshold, the switching valve is adjusted. At this time, the pressure and other parameters in the system are more stable, and the load on the compressor when it starts is relatively small, which is conducive to the smooth start of the compressor and reduces the impact on the compressor and the entire refrigeration system during startup. When the waiting time after the switching valve adjustment exceeds a second time threshold, the compressor is started. This ensures that after the switching valve action is completed, the system has enough time to balance pressure and stabilize its state, avoiding problems such as refrigerant flow disorder in the system due to premature compressor startup, resulting in refrigerant waste or incomplete defrosting. In addition, the control logic provided in this application avoids unnecessary operation of the compressor and ineffective circulation of refrigerant, enabling the system to make more rational use of energy during defrosting and cooling processes, reducing overall power consumption. In defrosting mode, the compressor is only started after the switching valve is adjusted to the correct position and the waiting time meets the requirements, which optimizes the compressor start-up time, avoids energy waste, helps to achieve energy-saving goals, and reduces user operating costs.

[0073] In some embodiments, the first duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the defrosting mode.

[0074] For example, assuming the first duration threshold is t1, the ambient temperature is T, and the refrigerant flow rate in defrost mode is q, then t1 = aq + b, t1 = aT + b, or t1 = a(q + T) + b, where a and b are correction coefficients, and a is a negative number. The first duration threshold is inversely proportional to the refrigerant flow rate in defrost mode and the ambient temperature. The higher the ambient temperature, the shorter the equilibrium time, and the shorter the first duration threshold; the larger the refrigerant flow rate in defrost mode, the shorter the equilibrium time, and the shorter the first duration threshold.

[0075] In some embodiments of this application, under high-temperature conditions, if the first time threshold is too long, the compressor will be shut down for an extended period, leading to significant pressure changes within the refrigeration system and potentially disrupting pressure balance. Therefore, shortening the first time threshold allows the system to enter the defrosting process promptly, and through operations such as refrigerant flow switching, system pressure balance can be restored more quickly. Under low-temperature conditions, appropriately extending the first time threshold allows sufficient time for the system pressure to adjust naturally before entering defrosting, creating conditions for pressure balance restoration during subsequent defrosting. A larger refrigerant flow rate accelerates heat transfer and system pressure changes; shortening the first time threshold allows the system to enter the defrosting state more quickly, accelerating the balancing of system parameters such as temperature and pressure. Extending the first time threshold with a smaller refrigerant flow rate allows the system to gradually adjust under relatively stable conditions, causing system parameters to slowly approach equilibrium during defrosting, preventing excessive fluctuations in system parameters due to overly abrupt defrosting operations, and improving the stability and reliability of the system's self-balancing mechanism.

[0076] In some embodiments, the second duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the defrosting mode.

[0077] For example, assuming the second duration threshold is t2, the ambient temperature is T, and the refrigerant flow rate in defrost mode is q, then t2 = cq + d, t2 = cT + d, or t2 = c(q + T) + d, where c and d are correction coefficients, and c is a negative number. The second duration threshold is inversely proportional to the refrigerant flow rate in defrost mode and the ambient temperature. The higher the ambient temperature, the shorter the equilibrium time, and therefore the shorter the second duration threshold; the larger the refrigerant flow rate in defrost mode, the shorter the equilibrium time, and therefore the shorter the second duration threshold.

[0078] In some embodiments of this application, changes in ambient temperature affect the pressure state within the refrigeration system. In high-temperature environments, system pressure changes relatively quickly; a shorter second time threshold allows the compressor to start promptly, enabling the system pressure to quickly return to normal refrigeration levels and preventing excessive pressure fluctuations. In low-temperature environments, system pressure changes more slowly; extending the second time threshold allows sufficient time for the system to naturally stabilize after the switching valve adjustment, allowing the compressor to start only after the pressure reaches a suitable level. This helps maintain system pressure balance and reduces impact on system components. Larger refrigerant flow rates cause more rapid changes in system parameters such as pressure and temperature. Setting a shorter second time threshold allows the compressor to start quickly, enabling the system to rapidly return to normal operation after defrosting, accelerating system parameter stabilization, and achieving system self-balancing. Conversely, when the refrigerant flow rate is low, system parameter changes are relatively gradual. Extending the second time threshold allows more time for internal adjustments after the switching valve adjustment, allowing the compressor to start only after all parameters have stabilized. This improves system stability, enabling the system to achieve self-balancing more smoothly and reducing the impact on the entire refrigerator refrigeration system.

[0079] In some embodiments, the method further includes: when the refrigerator is detected to have entered the cooling mode, controlling the compressor to stop and recording a second shutdown duration of the compressor; when the second shutdown duration is longer than a preset third duration threshold, adjusting the switching valve to switch the flow direction of the refrigerant from a second flow direction to a first flow direction; and controlling the compressor to start.

[0080] Referring to Figure 9, which is a flowchart of the controller in cooling mode according to some embodiments of this application, the controller is further configured to execute steps S21 to S25. When defrosting is complete and cooling is required, the controller first controls the compressor to stop and records the compressor's stop time as a second stop time (S22), and determines whether the second stop time has reached a third time threshold (S23). When the compressor's second stop time reaches the third time threshold, the switching valve is adjusted (S24). At this time, ports 41 and 43, ports 46 and 47, and ports 44 and 45 in the switching valve 4 are connected, so that the refrigerant flow direction is switched from the second flow direction to the first flow direction. After the switching valve is adjusted, the compressor starts running immediately (S25).

[0081] In some embodiments of this application, when the refrigerator switches from defrosting mode to cooling mode, the compressor is allowed to stop for a period of time, and a second stop duration is recorded. The compressor is then restarted only after the second stop duration exceeds a third duration threshold. This allows for better pressure balance within the compressor during the stop period, preventing excessive mechanical stress and current surges at startup due to large pressure differences, effectively extending the compressor's lifespan. The third duration threshold also prevents the compressor from starting immediately after defrosting, avoiding multiple starts in a short period due to frequent switching between defrosting and cooling modes, thus reducing the risk of wear and failure caused by frequent compressor starts. In addition, the switching valve is adjusted to switch the refrigerant flow from the second flow direction in defrosting mode to the first flow direction in cooling mode only after the compressor has been stopped for a certain period of time. This provides a stable system state for the switching valve to operate, which can avoid interference with the refrigerant flow switching due to the compressor starting too early. This ensures a smooth transition of the system from defrosting to cooling. Furthermore, the reasonable switching logic ensures that when the system starts in cooling mode, the refrigerant can flow quickly and orderly according to the cooling mode's circulation path, rapidly establishing a cooling cycle, thereby effectively improving cooling efficiency and enabling the refrigerator to recover to the set low temperature state more quickly.

[0082] In some embodiments, the third duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the cooling mode.

[0083] For example, assuming the third time threshold is t3, the ambient temperature is T, and the refrigerant flow rate in the cooling mode is p, then t3 = ep + f, t3 = eT + f, or t3 = e(p + T) + f, where e and f are correction coefficients, and e is negative. The third time threshold is inversely proportional to the refrigerant flow rate in the cooling mode and the ambient temperature. The higher the ambient temperature, the shorter the equilibrium time, and the shorter the third time threshold; the larger the refrigerant flow rate in the cooling mode, the shorter the equilibrium time, and the shorter the third time threshold.

[0084] In some embodiments of this application, under high-temperature conditions, the system pressure fluctuates greatly due to temperature changes. Shortening the third time threshold allows the compressor to start promptly, enabling the system pressure to quickly recover to the normal refrigeration state, preventing damage to the system from excessively high or low pressure and maintaining pressure balance. Under low-temperature conditions, the system pressure is relatively stable. Extending the third time threshold allows the system pressure to adjust naturally during compressor shutdown, resulting in a smoother transition to refrigeration state upon startup, reducing pressure shocks and ensuring system pressure self-balancing. Larger refrigerant flow rates cause rapid changes in system parameters. A shorter third time threshold allows the compressor to start promptly, enabling the system to quickly adapt to changes, maintain stable operation, and achieve system self-balancing. With smaller refrigerant flow rates, system parameters change slowly. Extending the third time threshold allows the system sufficient time to adjust its internal state, allowing the compressor to start only after all parameters have stabilized. This prevents system oscillations or instability caused by improper startup timing, improving the reliability and stability of system operation and ensuring system self-balancing.

[0085] In some embodiments of this application, the switching valve includes seven ports and is capable of switching between a first flow direction and a second flow direction, as well as between the second flow direction and the first flow direction.

[0086] In some embodiments, referring to Figure 10, which is a schematic diagram of the structure of a first type of switching valve provided in some embodiments of this application, the switching valve includes a valve body actuator 401 and a main valve body 402, wherein the main valve body 402 has 7 ports and has the functions of defrosting throttling, refrigeration throttling switching and condenser / evaporator high and low pressure function switching, wherein 3 ports (41-43) are configured to control the defrosting and throttling branches, and wherein 4 ports (44-47) are configured to four-way reversing and switch the flow direction of refrigerant between the evaporator and the condenser.

[0087] Referring to Figure 11, which is a schematic diagram of the operation of the first switching valve provided in the embodiment shown in Figure 10, the internal structure of the main valve body 402 is shown in Figure 11. The main valve body 402 has two valve cores, namely a first valve core 4021 and a second valve core 4022, which are connected in series coaxially. In some embodiments, the first valve core and the second valve core are spherical. The first valve core 4021 has a single channel, one end of which is connected to port 41, and the other end is configured to switch between ports 42 and 43, thereby connecting port 41 to port 42 or 43. The second valve core 4022 has a dual channel, each channel having two ports. The four ports of the second valve core 4022 are configured to be connected to ports 44-47 respectively to switch the communication relationship between ports 44-47, realizing the switching of refrigerant between the first flow direction and the second flow direction. In some embodiments, the two valve cores are isolated by a partition 404, and the valve body driver 401 at the upper part of the main valve body drives a gear (not shown) to drive the valve cores to rotate synchronously, thereby achieving the channel switching function. The sealing device 403 acts as a seal, creating a sealed space within the switching valve to prevent refrigerant from flowing out. The partition 404 divides the internal space of the switching valve 4 into an upper first space and a lower second space. At this time, high-temperature, high-pressure refrigerant fills the second space, where the lower second valve core is located, through the bottom pipe, minimizing its impact on the circulation in the upper first space. In some embodiments, the partition 404 may be omitted, and the compressor exhaust directly enters the entire space of the main valve body from the bottom connecting pipe. The refrigeration cycle is represented by the solid white line, with port connections of 46 and 47, 41 and 43, and 45 and 44. When switching to defrost mode, the valve body actuator 401 drives the gear transmission to rotate the valve core synchronously by 180°, achieving the channel switching function. In this case, the port connections become the black dashed line in the diagram below, with 46 and 45 connected, 42 and 41 connected, and 47 and 44 connected.

[0088] In other embodiments, referring to FIG12, FIG12 is a schematic diagram of the structure of a second switching valve provided in some embodiments of this application. The switching valve 4 includes a drive device 411. The drive device 411 may be, for example, a motor. The switching valve 4 also includes a transmission shaft 412, which is connected to the drive device 411 and rotates under the drive of the drive device 411. The switching valve 4 also includes a moving part 413, on which the transmission shaft 412 is fixed, and the moving part 413 can rotate about an axis under the action of the drive device 411 and the transmission shaft 412. The switching valve 4 also includes a fixing part 414.

[0089] Referring to Figure 13, which is a schematic diagram of the second type of switching valve shown in Figure 12 in cooling mode according to some embodiments of this application, the moving part 413 has two recessed slots 415, which are configured to connect to the through holes of the fixed part 414, thus serving a communication function. The fixed part 414 has seven or more through holes, which form the ports of the switching valve. One side of the fixed part 414 (i.e., one port of the through hole) cooperates with the moving part 413 to satisfy the connection / disconnection relationship, and the other side of the fixed part 414 (i.e., the other end of the through hole) is fixedly connected to the refrigerant flow pipe. When the moving part 413 rotates under the drive of the driving device 411 and the transmission shaft 412, the slots 415 can connect to different through holes on the fixed part 414 to realize the switching of the refrigerant between the first flow direction and the second flow direction. Referring to Figure 13, ports 45 and 44 are through holes located on the fixed component 414 and can be directly connected. Ports 46 and 47 connect to one of the slots 415, and ports 41 and 43 connect to the other slot 415. During the refrigeration cycle, the port connections are: 46 and 47 connected, 41 and 43 connected, and 45 and 44 connected. Referring to Figure 14, Figure 14 is a schematic diagram of the second type of switching valve in defrost mode provided in some embodiments of this application. When the refrigerator switches from refrigeration mode to defrost mode, the moving component 413 can rotate around the axis to the position shown in Figure 14 under the action of the drive device 411 and the transmission shaft 412. At this time, ports 45 and 46 are through holes located on the fixed component 414 and can be directly connected. Ports 44 and 47 connect to one of the slots 415, and ports 41 and 42 connect to the other slot 415. During the defrost cycle, the port connections are: 46 and 45 connected, 42 and 41 connected, and 47 and 44 connected.

[0090] In some embodiments of this application, the switching valve can freely switch between defrosting and cooling modes to meet the needs of different operating stages of the refrigerator. During defrosting, the switching valve switches the refrigerant flow to a second direction, allowing the refrigerant to flow along a specific path and efficiently melt the frost layer on the evaporator surface. During cooling, the switching valve switches the refrigerant flow to a first direction, allowing the refrigerant to run along the refrigeration cycle path to achieve the cooling function and ensure the refrigerator operates normally. The seven ports of the switching valve provide more connection and control possibilities for the refrigerator's cooling and defrosting system. It can connect to multiple components, such as the evaporator, condenser, and compressor, allowing the refrigerant to flow precisely to the required components in different modes, achieving complex system functions and improving the overall performance of the refrigerator. In different modes, the switching valve can precisely adjust the refrigerant flow direction according to actual needs, making the refrigerant flow more smoothly and rationally in the system, reducing energy loss and improving cooling and defrosting efficiency. In addition, by precisely controlling the refrigerant flow, ineffective refrigerant flow and energy waste are avoided, making the refrigerator more energy-efficient during the cooling and defrosting process. Reasonable flow switching can make the compressor and other components work more efficiently, reduce unnecessary running time, reduce energy consumption, and save electricity costs.

[0091] Referring to Figure 15, which is a flowchart of a defrosting control method for a refrigerator according to some embodiments of this application, the defrosting control method is implemented by a controller in the refrigerator, and the method includes:

[0092] S1. When the refrigerator is detected to have entered defrost mode, control the compressor to stop and record the first shutdown duration of the compressor;

[0093] S2. When the first shutdown duration exceeds a preset first duration threshold, adjust the switching valve to switch the refrigerant flow direction from the first flow direction to the second flow direction, and record the waiting time of the switching valve after adjustment; wherein, the switching valve is configured to change the refrigerant flow direction in the refrigeration system; the refrigerant flow direction includes the first flow direction in the refrigeration mode and the second flow direction in the defrost mode;

[0094] S3. When the waiting time exceeds a preset second time threshold, control the compressor to start.

[0095] In some embodiments, the method further includes:

[0096] When the refrigerator is detected to have entered cooling mode, the compressor is controlled to stop, and the second shutdown duration of the compressor is recorded;

[0097] When the second shutdown duration exceeds the preset third duration threshold, the switching valve is adjusted to switch the refrigerant flow direction from the second flow direction to the first flow direction;

[0098] Control the compressor to start.

[0099] In some embodiments, the first duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the defrosting mode.

[0100] In some embodiments, the second duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the defrosting mode.

[0101] In some embodiments, the third duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the cooling mode.

[0102] It is worth noting that the specific working process of the defrosting control method of the refrigerator described in some embodiments of this application can be referred to the working process of the controller in the refrigerator described in the above embodiments, and will not be repeated here.

[0103] In some embodiments of this application, when the refrigerator is defrosting in reverse flow mode, the system self-balancing problem is considered. By setting a first time threshold, when the refrigerator enters defrosting mode, the compressor is allowed to stop for a certain period of time before subsequent operations are performed, preventing the compressor from starting frequently in a short period of time. When the first stop time is longer than the first time threshold, the switching valve is adjusted. At this time, the pressure and other parameters in the system are more stable, and the load when the compressor starts is relatively small, which is conducive to the smooth start of the compressor and reduces the impact on the compressor and the entire refrigeration system during startup. When the waiting time after the switching valve adjustment is longer than the second time threshold, the compressor is started. This ensures that after the switching valve action is completed, the system has enough time to balance pressure and stabilize its state, avoiding problems such as refrigerant flow disorder in the system due to premature compressor startup, resulting in refrigerant waste or incomplete defrosting. In addition, the control logic provided in this application avoids unnecessary operation of the compressor and ineffective circulation of refrigerant, enabling the system to make more rational use of energy during defrosting and cooling processes, reducing overall power consumption. In defrosting mode, the compressor is only started after the switching valve is adjusted to the correct position and the waiting time meets the requirements, which optimizes the compressor start-up time, avoids energy waste, helps to achieve energy-saving goals, and reduces user operating costs.

[0104] The above description is only a part of the embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A refrigerator, comprising: Box; A refrigeration system configured to provide cooling capacity to a refrigerator, the refrigeration system comprising a compressor, a condenser, and an evaporator connected in sequence by pipes; A switching valve, located in the refrigeration system, is configured to switch the flow direction of the refrigerant in the refrigeration system; wherein the refrigerant flow direction includes a first flow direction operating in refrigeration mode and a second flow direction operating in defrost mode; and The controller is configured to: When the refrigerator is detected to have entered defrost mode, the compressor is controlled to stop, and the first shutdown duration of the compressor is recorded. When the first shutdown duration exceeds a preset first duration threshold, the switching valve is adjusted to switch the refrigerant flow direction from the first flow direction to the second flow direction, and the waiting time of the switching valve after adjustment is recorded. When the waiting time exceeds a preset second time threshold, the compressor is controlled to start.

2. The refrigerator as described in claim 1, wherein, The method further includes: When the refrigerator is detected to have entered cooling mode, the compressor is controlled to stop, and the second shutdown duration of the compressor is recorded; When the second shutdown duration exceeds the preset third duration threshold, the switching valve is adjusted to switch the refrigerant flow direction from the second flow direction to the first flow direction; Control the compressor to start.

3. The refrigerator as described in claim 1, wherein, The refrigerator also includes: The first branch is located between the switching valve and the evaporator, and includes a first capillary tube and a first drying filter connected in sequence, wherein one end of the first capillary tube is connected to the evaporator and one end of the first drying filter is connected to the switching valve. The second branch, located between the switching valve and the evaporator, includes a second capillary tube and a second dryer filter connected in sequence, wherein one end of the second capillary tube is connected to the switching valve and one end of the second dryer filter is connected to the evaporator.

4. The refrigerator as described in claim 3, wherein, The flow rate of the second capillary is greater than that of the first capillary.

5. The refrigerator as described in claim 3, wherein, When the refrigeration system is operating in the refrigeration mode, the refrigerant flows out from the switching valve and then flows sequentially through the first dryer filter, the first capillary tube, and the evaporator; when the refrigeration system is operating in the defrost mode, the refrigerant flows out from the evaporator and then flows sequentially through the second dryer filter, the second capillary tube, and the switching valve.

6. The refrigerator as claimed in claim 3, wherein, The refrigerator also includes: The decondensation assembly includes a condensate evaporation pipe and a decondensation pipe. The condensate evaporation pipe is located between the compressor and the decondensation pipe and is connected to the air outlet of the compressor. The decondensation pipe is located between the condensate evaporation pipe and the switching valve.

7. The refrigerator as claimed in claim 1, wherein, The first duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the defrosting mode.

8. The refrigerator as claimed in claim 1, wherein, The second duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the defrosting mode.

9. The refrigerator as claimed in claim 2, wherein, The third duration threshold is inversely proportional to the ambient temperature and / or the refrigerant flow rate in the cooling mode.

10. The refrigerator as claimed in claim 3, wherein, The switching valve includes: Valve body actuator; and Main valve body, the main valve body comprising: It has 7 ports, of which the first port is connected to the condenser, the second port is connected to the first dryer filter on the first branch, the third port is connected to the second capillary tube on the second branch; the fourth to seventh ports are respectively connected to the compressor outlet, the compressor inlet, the condenser and the compressor; The first valve core includes a channel, one end of which is connected to a first port, and the other end is configured to switch between a second port and a third port when the first valve core rotates under the drive of a valve body actuator. The second valve core includes two channels, each channel having two ports. The ports of the channels of the second valve core are configured to switch between the fourth and seventh ports when the second valve core rotates under the drive of the valve body actuator to achieve switching between the first flow direction and the second flow direction.

11. The refrigerator according to claim 3, wherein, The switching valve includes: Drive unit; A drive shaft is connected to the drive device; A moving component is configured to rotate about an axis under the drive of a drive device and a drive shaft; the transmission component includes two slots; and A fixing component, the fixing component including 7 through holes; The moving component is configured such that when it rotates under the drive of the drive device and the transmission shaft, the two slots connect different through holes on the fixed component to realize the switching of the refrigerant between the first flow direction and the second flow direction.

12. A defrosting control method for a refrigerator, comprising: When the refrigerator is detected to have entered defrost mode, the compressor is stopped and the first shutdown duration of the compressor is recorded. When the first shutdown duration exceeds a preset first duration threshold, the switching valve is adjusted to switch the refrigerant flow direction from the first flow direction to the second flow direction, and the waiting time of the switching valve after adjustment is recorded; wherein, the switching valve is configured to change the refrigerant flow direction in the refrigeration system; the refrigerant flow direction includes the first flow direction when operating in refrigeration mode and the second flow direction when operating in defrost mode; When the waiting time exceeds a preset second time threshold, the compressor is controlled to start.

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