A refrigerator and its control method

Abstract

This invention discloses a refrigerator and its control method. The refrigerator includes: a compressor, a condenser, a first throttling device, a first evaporator, and a gas-liquid separator connected in sequence; an oil circulation control device, the first end of which is connected to the liquid outlet of the gas-liquid separator, and the second end of which is connected between the compressor and the condenser, for delivering oil from the gas-liquid separator to the condenser when the refrigerator is in defrost mode; a bypass pipeline connected in parallel with the first throttling device; a first circuit switching device, which is connected to the condenser, the first throttling device, and the first bypass pipeline respectively, for switching the condenser to be connected to either the first bypass pipeline or the first throttling device; and a controller, for controlling the compressor to shut down, the oil circulation control device to deliver oil from the gas-liquid separator to the condenser, and the circuit switching device to switch the condenser to be connected to the first bypass pipeline when the refrigerator is in defrost mode. Therefore, this invention can improve the defrost efficiency of the refrigerator.

Description

Technical Field

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

[0002] Currently, refrigerators primarily use a reverse refrigerant cycle for defrosting. This method reverses the refrigerant flow, turning the evaporator into a condenser and vice versa, using the heat of the refrigerant to melt the frost on the evaporator. While this method can melt the frost on the refrigerator evaporator to some extent, because refrigerators generally use low-temperature refrigerants, the pressure difference between the condensing and evaporating pressures in the refrigerator system is very low at low ambient temperatures. This pressure difference often fails to reach the minimum pressure required for the four-way valve to switch, preventing the valve from switching between cooling and reverse defrosting. Consequently, the defrosting efficiency of the refrigerator is low. Summary of the Invention

[0003] This invention provides a refrigerator and its control method, which can improve the defrosting efficiency of the refrigerator.

[0004] The refrigerator provided in the first embodiment of the present invention includes:

[0005] A refrigerant circulation loop includes a compressor, a condenser, a first throttling device, a first evaporator, and a gas-liquid separator connected in sequence; wherein the inlet of the gas-liquid separator is connected to the first evaporator, and the gas outlet of the gas-liquid separator is connected to the compressor.

[0006] An oil circulation control device, with its first end connected to the liquid outlet of the gas-liquid separator and its second end connected to the pipeline between the compressor and the condenser, is used to transport the oil in the gas-liquid separator to the condenser when the refrigerator is in defrosting mode.

[0007] The first bypass pipeline is connected in parallel with the first throttling device;

[0008] The first loop switching device is connected to the condenser, the first throttling device and the first bypass line respectively, and is used to switch the condenser to be connected to the first bypass line or to the first throttling device.

[0009] Controller, used for:

[0010] When the refrigerator is in defrost mode, the compressor is controlled to shut down, the first circuit switching device is controlled to switch the condenser to be connected to the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separator to the condenser.

[0011] In the second embodiment of the refrigerator provided by the present invention, the controller is further configured to:

[0012] When the refrigerator is in cooling mode, the compressor is turned on, the oil circulation control device is stopped from supplying oil to the condenser, and the first circuit switching device is switched to connect the condenser to the first throttling device.

[0013] The refrigerator provided in the third embodiment of the present invention includes, in particular, an oil circulation control device comprising:

[0014] A switching valve, the first end of which is the first end of the oil circulation control device, is used to open or close under the control of the controller;

[0015] An oil circulation pump, the first end of which is connected to the second end of the switching valve, and the second end of which is the second end of the oil circulation control device, is used to deliver the oil in the gas-liquid separator to the condenser when the switching valve is opened.

[0016] The refrigerator provided in the fourth embodiment of the present invention further includes:

[0017] A first temperature detection device is installed on the first evaporator and is used to detect the temperature of the first evaporator;

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

[0019] When the temperature of the first evaporator is detected to be greater than a preset temperature threshold, the refrigerator is controlled to switch to cooling mode.

[0020] The refrigerator provided in the fifth embodiment of the present invention further includes:

[0021] The refrigerant circulation branch includes a second evaporator and a second throttling device; wherein, the first end of the second throttling device is connected to the pipeline between the condenser and the first circuit switching device, and the second end of the second throttling device is connected to the pipeline between the gas-liquid separation device and the first evaporator through the second evaporator;

[0022] The second bypass pipeline is connected in parallel with the second throttling device;

[0023] The second loop switching device is connected to the condenser, the second throttling device and the second bypass line respectively, and is used to switch the condenser to be connected to the second throttling device or to the second bypass line.

[0024] Therefore, when the refrigerator is in defrost mode, the controller is also used to:

[0025] The second circuit switching device is controlled to switch the condenser to be connected to the second bypass pipeline.

[0026] In the sixth embodiment of the refrigerator provided by the present invention, the controller is further configured to:

[0027] When the refrigerator is in cooling mode, the compressor is turned on, the oil circulation control device is stopped supplying oil to the condenser, the first circuit switching device is switched to connect the condenser to the first throttling device, and the second circuit switching device is switched to connect the condenser to the second throttling device.

[0028] A refrigerator control method provided in the seventh embodiment of the present invention includes a compressor, a condenser, a first throttling device, a first evaporator, a gas-liquid separator, an oil circulation control device, a first bypass pipeline, and a first circuit switching device; wherein the compressor, the condenser, the first throttling device, the first evaporator, and the gas-liquid separator are connected in sequence; the first end of the oil circulation control device is connected to the liquid outlet of the gas-liquid separator, and the second end of the oil circulation control device is connected to the pipeline between the compressor and the condenser; the first bypass pipeline is connected in parallel with the first throttling device; and the first circuit switching device is connected to the condenser, the first throttling device, and the first bypass pipeline respectively; then, the method includes:

[0029] When the refrigerator is in defrost mode, the compressor is controlled to shut down, the first circuit switching device is controlled to switch the condenser to be connected to the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separator to the condenser.

[0030] The refrigerator control method provided in the eighth embodiment of the present invention further includes:

[0031] When the refrigerator is in cooling mode, the compressor is turned on, the oil circulation control device is stopped from supplying oil to the condenser, and the first circuit switching device is switched to connect the condenser to the first throttling device.

[0032] The refrigerator control method provided in the ninth embodiment of the present invention further includes a second evaporator, a second throttling device, a second bypass pipeline, and a second circuit switching device; wherein, the first end of the second throttling device is connected to the pipeline between the condenser and the first circuit switching device, and the second end of the second throttling device is connected to the pipeline between the gas-liquid separator and the first evaporator through the second evaporator; the second bypass pipeline is arranged in parallel with the second throttling device; the second circuit switching device is respectively connected to the condenser, the second throttling device, and the second bypass pipeline; then, the method further includes:

[0033] The second circuit switching device is controlled to switch the condenser to be connected to the second bypass pipeline.

[0034] The refrigerator control method provided in the tenth embodiment of the present invention further includes:

[0035] When the refrigerator is in cooling mode, the compressor is turned on, the oil circulation control device is stopped supplying oil to the condenser, the first circuit switching device is switched to connect the condenser to the first throttling device, and the second circuit switching device is switched to connect the condenser to the second throttling device.

[0036] Compared to existing technologies, the refrigerator and its control method provided in this embodiment of the invention include: a refrigerant circulation loop consisting of a compressor, a condenser, a first throttling device, a first evaporator, and a gas-liquid separator connected in sequence; an oil circulation control device, the first end of which is connected to the liquid outlet of the gas-liquid separator, and the second end of which is connected to the pipeline between the compressor and the condenser; a first bypass pipeline connected in parallel with the first throttling device; and a first loop switching device, which is connected to the condenser, the first throttling device, and the first bypass pipeline respectively, and is used to switch the condenser to be connected to either the first bypass pipeline or the first throttling device. When the refrigerator is in defrost mode, the controller controls the compressor to shut down, controls the first loop switching device to switch the condenser to be connected to the first bypass pipeline, and controls the oil circulation control device to deliver the oil from the gas-liquid separator to the condenser. Therefore, when the refrigerator is in defrost mode, the oil separated by the gas-liquid separator can be delivered to the condenser, allowing the oil to exchange heat with the condenser and its surrounding environment. After absorbing heat, the oil flows through the first bypass pipe to the first evaporator. Because the oil is at a higher temperature after absorbing heat, it can heat the frost adhering to the surface of the first evaporator, melting the frost and achieving the purpose of defrosting. Simultaneously, since the specific heat capacity of oil is much higher than that of refrigerant, compared to the prior art, this invention can, on the one hand, utilize the oil to exchange more heat with the condenser and its surrounding environment to defrost the first evaporator, improving defrosting efficiency; on the other hand, it can also store a large amount of cold energy from the first evaporator, avoiding waste of cold energy during the defrosting process, thereby improving the refrigerator's cooling efficiency. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a first refrigerator provided in an embodiment of the present invention.

[0038] Figure 2 This is a schematic diagram of the structure of a second refrigerator provided in an embodiment of the present invention.

[0039] Figure 3 This is a schematic diagram of the structure of a third type of refrigerator provided in an embodiment of the present invention.

[0040] Figure 4 This is a schematic diagram of the refrigeration system of a single-system refrigerator provided in an embodiment of the present invention.

[0041] Figure 5 This is a schematic diagram of the oil flow direction in a single-system refrigerator under defrosting mode, provided by an embodiment of the present invention.

[0042] Figure 6This is a schematic diagram of the refrigerant flow direction in a single-system refrigerator in refrigeration mode, provided by an embodiment of the present invention.

[0043] Figure 7 This is a structural schematic diagram of the fourth type of refrigerator provided in an embodiment of the present invention.

[0044] Figure 8 This is a schematic diagram of the refrigeration system of a dual-system refrigerator provided in an embodiment of the present invention.

[0045] Figure 9 This is a schematic diagram of the oil flow direction in defrosting mode of a dual-system refrigerator provided by an embodiment of the present invention.

[0046] Figure 10 This is a schematic diagram of the refrigerant flow direction in the cooling mode of a dual-system refrigerator provided by an embodiment of the present invention.

[0047] The reference numerals in the attached drawings are as follows: 1. Compressor; 2. Condenser; 3. First throttling device; 4. First evaporator; 5. Gas-liquid separation device; 6. Oil circulation control device; 61. Switch valve; 62. Oil circulation pump; 7. First bypass pipeline; 8. First circuit switching device; 9. Second evaporator; 10. Second throttling device; 11. Second bypass pipeline; 12. Second circuit switching device; 100. Housing; 200. Door; 201. Door outer shell; 202. Door inner liner; 203. Upper end cover; 204. Lower end cover. Detailed Implementation

[0048] 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 skilled in the art without creative effort are within the scope of protection of this application.

[0049] 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, and 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, and therefore should not be construed as a limitation of this application.

[0050] 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, "multiple" means two or more.

[0051] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" 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.

[0052] See Figure 1 This is a schematic diagram of the structure of a refrigerator provided in an embodiment of the present invention.

[0053] The refrigerator provided in this embodiment of the invention includes a cabinet 100. The cabinet 100 has at least one compartment. Specifically, as shown... Figure 1 As shown, the refrigerator in this embodiment has an approximately rectangular parallelepiped shape. The refrigerator includes a cabinet 100 defining a storage space, and the cabinet 100 has at least one compartment. Depending on its purpose, the compartment can be configured as a refrigerator compartment, freezer compartment, variable temperature compartment, etc. For example, in... Figure 1 The upper compartment is a refrigerator compartment, and the lower compartment is a freezer compartment. Each compartment opening has one or more doors 200. For example, in... Figure 2 In the middle, the upper part of the refrigerator compartment is equipped with a double door; the door 200 includes a door shell 201 located outside the cabinet 100, a door inner liner 202 located inside the cabinet 100, an upper end cover 203, a lower end cover 204, and an insulation layer located between the door shell 201, the door inner liner 202, the upper end cover 203, and the lower end cover 204. Typically, the insulation layer is filled with foam material.

[0054] See Figure 3 and Figure 4 In the refrigeration system of a single-system refrigerator, the refrigerator provided in this embodiment of the invention further includes a refrigerant circulation loop, which is used to cool the compartments within the cabinet 100. In a specific embodiment, see... Figure 4The refrigerant circulation loop includes a compressor 1, a condenser 2, a first throttling device 3, a first evaporator 4, and a gas-liquid separator 5 connected in sequence. Specifically, the exhaust port of the compressor 1 is connected to the first end of the condenser 2, the second end of the condenser 2 is connected to the first end of the first throttling device 3, the second end of the first throttling device 3 is connected to the first end of the first evaporator 4, the second end of the first evaporator 4 is connected to the inlet of the gas-liquid separator 5, and the gas outlet of the gas-liquid separator 5 is connected to the suction port of the compressor 1. The refrigerator also includes an oil circulation control device 6, the first end of which is connected to the liquid outlet of the gas-liquid separator 5, and the second end of which is connected to the pipeline between the compressor 1 and the condenser 2. The oil circulation control device 6 is used to transport the oil in the gas-liquid separator 5 to the condenser 2 when the refrigerator is in defrost mode. In addition, the refrigerator also includes a first bypass pipe 7 and a first circuit switching device 8; wherein, the first bypass pipe 7 is arranged in parallel with the first throttling device 3; the first circuit switching device 8 is connected to the condenser 2, the first throttling device 3 and the first bypass pipe 7 respectively; specifically, the first end of the first circuit switching device 8 is connected to the second end of the condenser 2, the second end of the first circuit switching device 8 is connected to the first end of the first bypass pipe 7, and the third end of the first circuit switching device 8 is connected to the first end of the first throttling device 3. The first circuit switching device 8 is used to switch the condenser 2 to be connected to the first bypass pipe 7 or to the first throttling device 3. In addition, the second end of the first bypass pipe 7 is connected to the pipe between the first evaporator 4 and the first throttling device 3.

[0055] Specifically, in the refrigerator provided in this embodiment of the invention, the refrigerator further includes a controller connected to the compressor 1 to control the compressor 1; the controller is also connected to the oil circulation control device 6 to control the oil circulation control device 6; the controller is also connected to the first circuit switching device 8 to control the first circuit switching device 8 to switch the condenser 2 to be connected to the first bypass pipe 7 or to the first throttling device 3. Specifically, the controller is used for:

[0056] When the refrigerator is in defrost mode, the compressor 1 is turned off, the oil circulation control device 6 is controlled to deliver the oil in the gas-liquid separator 5 to the condenser 2, and the first circuit switching device 8 is controlled to switch the condenser 2 to be connected to the first bypass pipe 7.

[0057] In this embodiment, a gas-liquid separator 5 is installed in the refrigerant circulation loop of the refrigerator. This separator separates the refrigerant and the compressor oil from the compressor 1, allowing them to enter different channels. On one hand, in cooling mode, the refrigerant is used to cool different compartments; on the other hand, while the refrigerant is cooling, the compressor oil is stored in the gas-liquid separator 5 and used for defrosting when necessary. Specifically, when the refrigerator is in defrosting mode, the oil separated by the gas-liquid separator 5 is transported to the condenser 2, allowing the oil to exchange heat with the condenser 2 and its surrounding environment. After absorbing heat, the oil flows through the first bypass pipe 7 to the first evaporator 4. Because the oil is at a higher temperature after absorbing heat, it can heat the frost adhering to the surface of the first evaporator 4, melting the frost and achieving the purpose of defrosting. Meanwhile, since the specific heat capacity of engine oil is much higher than that of refrigerant, compared with the prior art, the present invention can, on the one hand, utilize engine oil to exchange more heat with condenser 2 and its surrounding environment to defrost the first evaporator 4, thereby improving defrosting efficiency; on the other hand, it can also store a large amount of cold energy from the first evaporator 4, avoiding waste of cold energy during the defrosting process, thereby improving the refrigeration efficiency of the refrigerator.

[0058] It should be noted that in existing technologies, besides defrosting via refrigerant reverse circulation, frost inside the refrigerator can also be melted by electric heating. However, electric defrosting efficiency is low, and the heat from the heating wire is not concentrated, easily diffusing into the refrigerator compartments, affecting the temperature of food stored inside and hindering food preservation. Compared to electric defrosting, this invention utilizes machine oil for defrosting, defrosting the first evaporator 4 from the inside. Compared to electric defrosting from the outside, this method melts frost more easily and has less impact on the compartment temperature. Furthermore, since machine oil has a much higher specific heat capacity than gas, it can store a large amount of cold energy from the first evaporator 4 during defrosting, avoiding waste of cold energy during the defrosting process. This provides better cooling for the condenser 2 and its surroundings, so that when the refrigerator restarts cooling, the refrigerant passes through the cooled condenser 2, resulting in better cooling efficiency and energy savings.

[0059] As one optional embodiment, the controller is further configured to:

[0060] When the cumulative cooling time of the refrigerator is detected to reach a preset time threshold, the refrigerator is controlled to switch to defrost mode.

[0061] It should be noted that, in addition to using the cumulative cooling time of the refrigerator reaching a preset time threshold as the condition for the start of defrosting, other defrosting conditions in existing technologies can also be referred to, and are not limited here.

[0062] In an optional embodiment, the refrigerator further includes:

[0063] The first temperature detection device is used to detect the temperature of the first evaporator 4;

[0064] Then, the controller is further configured to:

[0065] When the temperature of the first evaporator 4 is detected to be greater than the preset temperature threshold, the refrigerator is controlled to switch to cooling mode.

[0066] Optionally, the preset temperature threshold is 1°C.

[0067] Furthermore, the controller is also used for:

[0068] When the refrigerator is in cooling mode, the compressor 1 is turned on, the oil circulation control device 6 is stopped from supplying oil to the condenser 2, and the first circuit switching device 8 is switched to connect the condenser 2 to the first throttling device 3.

[0069] Specifically, attend Figure 4 The oil circulation control device 6 specifically includes:

[0070] The switching valve 61 has its first end being the first end of the oil circulation control device 6, which is used to open or close under the control of the controller.

[0071] The oil circulation pump 62 has its first end connected to the second end of the switching valve 61, and its second end is the second end of the oil circulation control device 6. It is used to deliver the oil in the gas-liquid separator 5 to the condenser 2 when the switching valve 61 is opened.

[0072] Understandably, see Figure 5 When the refrigerator is in defrost mode, the controller activates the switching valve 61 and the oil circulation pump 62, allowing the oil in the gas-liquid separator 5 to be pumped to the condenser 2 by the oil circulation pump 62. At this time, since the compressor 1 is off and the first throttling device 3 is not activated, the oil does not flow towards the left side of the compressor 1. Instead, it flows through the condenser 2, enters the first bypass pipe 7, then the first evaporator 4, and finally returns to the gas-liquid separator 5 for the next cycle. Conversely, when the refrigerator is in cooling mode, the controller closes the switching valve 61 and the oil circulation pump 62, stopping the oil circulation control device 6 from supplying oil to the condenser 2. This allows the oil to be stored in the gas-liquid separator 5 for the next defrost cycle.

[0073] Furthermore, the switching valve 61 is a solenoid valve.

[0074] For example, see Figure 5The control state of the single-system refrigerator provided in this embodiment of the invention in defrost mode is as follows: the compressor 1 is off, the B channel of the first circuit switching device 8 is closed, and the A channel is open, so that the condenser 2 is connected to the first bypass pipe 7. At this time, because the gas-liquid separation device 5 stores sufficient compressor 1 refrigerant oil, the controller controls the switching valve 61 and the oil circulation pump 62 to open, so as to transport the oil in the gas-liquid separation device 5 to the lower condenser 2, and then enter the first circuit switching device 8, and enter the first evaporator 4 after passing through the A channel. Since the oil absorbs more heat when it exchanges heat in the condenser 2, the temperature of the oil flowing through the first evaporator 4 is relatively high, so that the oil can be used to heat the frost attached to the surface of the first evaporator 4, so that the frost melts. Meanwhile, after absorbing the cold energy from the frost on the first evaporator 4, the oil continues to flow, entering the gas-liquid separator 5 from the second end of the first evaporator 4, and then flowing from the liquid outlet at the bottom of the gas-liquid separator 5 to the switching valve 61, where it is again pumped into the condenser 2 by the oil circulation pump 62. At this time, because the oil has absorbed the cold energy from the first evaporator 4, its temperature is low, thus allowing it to cool the condenser 2 and its surroundings. After absorbing heat, the oil enters the first evaporator 4 through the first bypass pipe 7 to defrost, and this cycle repeats to assist the refrigerator in defrosting quickly.

[0075] It should be noted that since engine oil is a liquid, it can store much more cold air than gas. Moreover, the engine oil flows from the internal pipe of the first evaporator 4, meaning that defrosting begins from inside the first evaporator 4. Therefore, it is easier to melt the frost, making the refrigerator's defrosting efficiency higher.

[0076] For example, see Figure 6The control state of the single-system refrigerator provided in this embodiment of the invention in refrigeration mode is as follows: the switching valve 61 and oil circulation pump 62 are closed, the A-channel of the first circuit switching device 8 is closed, the B-channel is open, and the compressor 1 starts working. At this time, low-temperature, low-pressure refrigerant is drawn into the compressor 1, compressed into high-temperature, high-pressure superheated gas in the cylinder of the compressor 1, and discharged from the exhaust port of the compressor 1 into the condenser 2. The high-temperature, high-pressure refrigerant gas dissipates heat through the condenser 2, and its temperature continuously decreases, gradually being cooled into room-temperature, high-pressure saturated vapor, and further cooled into saturated liquid. Then, the saturated liquid refrigerant enters the first circuit switching device 8 and enters the first throttling device 3 through the B-channel, and is throttled and depressurized by the first throttling device 3, turning the refrigerant into room-temperature, low-pressure wet vapor. Subsequently, the room-temperature, low-pressure wet vapor flows through the first evaporator 4, where it begins to absorb heat and vaporize, thereby reducing the temperature of the first evaporator 4 and its surroundings, turning the refrigerant into a low-temperature, low-pressure gas. Finally, the refrigerant from the first evaporator 4 passes through the gas-liquid separator 5 and returns to the suction port of the compressor 1 to start the next refrigeration cycle. This cycle repeats continuously, thereby transferring the heat inside the refrigerator to the outside air to achieve the purpose of refrigeration.

[0077] It should be noted that when compressor 1 starts working, the refrigerant circulation loop begins to flow. The oil that was previously pumped to the condenser 2 and evaporator by oil circulation pump 62 will be carried by the refrigerant back into the gas-liquid separator 5, and then flow to the bottom of the separator 5 for storage, preparing for the next defrost cycle. Furthermore, when the refrigerator restarts cooling, since the condenser 2 has been cooled by the oil, the refrigerant will experience better cooling as it passes through the cooled condenser 2, thus improving the refrigerator's cooling efficiency to some extent.

[0078] Specifically, the first throttling device 3 is a capillary tube.

[0079] Optionally, the first circuit switching device 8 includes:

[0080] The first three-way valve has its first to third ends connected to the second end of the condenser 2, the first end of the first bypass pipe 7, and the first end of the first throttling device 3, respectively. It is used to switch the condenser 2 to be connected to the first bypass pipe 7 or to the first throttling device 3.

[0081] Understandably, the first end of the first three-way valve is the first end of the first circuit switching device 8, the second end of the first three-way valve is the second end of the first circuit switching device 8, and the third end of the first three-way valve is the third end of the first circuit switching device 8.

[0082] Optionally, the first circuit switching device 8 includes:

[0083] The first solenoid valve is connected to the second end of the condenser 2 and the first end of the first bypass pipe 7, respectively.

[0084] The second solenoid valve is connected to the second end of the condenser 2 and the first end of the first throttling device 3, respectively.

[0085] See Figure 7 and Figure 8 In the dual-system refrigeration system, the refrigerator provided in this embodiment further includes:

[0086] The refrigerant circulation branch includes a second evaporator 9 and a second throttling device 10; wherein, the first end of the second throttling device 10 is connected to the pipeline between the condenser 2 and the first circuit switching device 8, and the second end of the second throttling device 10 is connected to the pipeline between the gas-liquid separation device 5 and the first evaporator 4 through the second evaporator 9.

[0087] The second bypass pipe 11 is connected in parallel with the second throttling device 10;

[0088] The second circuit switching device 12 is connected to the condenser 2, the second throttling device 10, and the second bypass pipe 11 respectively. It is used to switch the condenser 2 to be connected to the second throttling device 10 or to the second bypass pipe 11.

[0089] Therefore, when the refrigerator is in defrost mode, the controller is also used to:

[0090] The control second loop switching device 12 switches the condenser 2 to be connected to the second bypass pipeline 11.

[0091] Specifically, the second throttling device 10 is a capillary tube.

[0092] Specifically, the first end of the second loop switching device 12 is connected to the second end of the condenser 2, the second end of the second loop switching device 12 is connected to the first end of the second bypass pipe 11, and the third end of the first loop switching device 8 is connected to the first end of the second throttling device 10.

[0093] Optionally, the second circuit switching device 12 includes:

[0094] The second three-way valve has its first to third ends connected to the second end of the condenser 2, the first end of the second bypass pipe 11, and the first end of the second throttling device 10, respectively. It is used to switch the condenser 2 to be connected to the second bypass pipe 11 or to the second throttling device 10.

[0095] Understandably, the first end of the second three-way valve is the first end of the second circuit switching device 12, the second end of the second three-way valve is the second end of the second circuit switching device 12, and the third end of the second three-way valve is the third end of the second circuit switching device 12.

[0096] Optionally, the second circuit switching device 12 includes:

[0097] The third solenoid valve is connected to the second end of the condenser 2 and the first end of the second bypass pipe 11, respectively.

[0098] The fourth solenoid valve is connected to the second end of the condenser 2 and the first end of the second throttling device 10, respectively.

[0099] For example, see Figure 9 The control state of the dual-system refrigerator provided in this embodiment of the invention in defrost mode is as follows: the compressor 1 is off, the B channel of the first circuit switching device 8 is closed, and the A channel is open, so that the condenser 2 is connected to the first bypass pipe 7; the B channel of the second circuit switching device 12 is closed, and the A channel is open, so that the condenser 2 is connected to the second bypass pipe 11. At this time, the controller controls the switching valve 61 and the oil circulation pump 62 to open, so as to transport the oil in the gas-liquid separator 5 to the lower condenser 2, and then enter the first circuit switching device 8 and the second circuit switching device 12 respectively. After passing through the A channel of the first circuit switching device 8, it enters the first evaporator 4, and after passing through the A channel of the second circuit switching device 12, it enters the second evaporator 9. The high-temperature oil heats the frost attached to the surface of the first evaporator 4 and the second evaporator 9, so that the frost melts. At the same time, the oil absorbs the coldness of the frost on the first evaporator 4 and the second evaporator 9 and continues to flow, eventually flowing into the gas-liquid separator 5. The oil flowing into the gas-liquid separator 5 continues to flow from the liquid outlet at the bottom of the gas-liquid separator 5 to the switch valve 61, and is then pumped back into the condenser 2 by the oil circulation pump 62. At this time, because the oil absorbs the cooling energy from the first evaporator 4 and the second evaporator 9, the oil temperature is low. Therefore, the oil can be used to cool the condenser 2 and its surroundings. After absorbing heat, the oil enters the first evaporator 4 through the first bypass pipe 7 for defrosting, and enters the second evaporator 9 through the second bypass pipe 11 for defrosting. This cycle repeats to assist the refrigerator in defrosting quickly.

[0100] Furthermore, the controller is also used for:

[0101] When the refrigerator is in cooling mode, the compressor 1 is turned on, the oil circulation control device 6 stops supplying oil to the condenser 2, the first circuit switching device 8 switches the condenser 2 to be connected to the first throttling device 3, and the second circuit switching device 12 switches the condenser 2 to be connected to the second throttling device 10.

[0102] For example, see Figure 10 The control state of the dual-system refrigerator provided in this embodiment of the invention in refrigeration mode is as follows: the switching valve 61 and the oil circulation pump 62 are closed; the A-channel of the first circuit switching device 8 is closed and the B-channel is open; the A-channel of the second circuit switching device 12 is closed and the B-channel is open; and the compressor 1 starts working. At this time, low-temperature, low-pressure refrigerant is drawn into the compressor 1 and compressed into high-temperature, high-pressure superheated gas in the cylinder of the compressor 1, and then discharged from the exhaust port of the compressor 1 into the condenser 2. The high-temperature, high-pressure refrigerant gas dissipates heat through the condenser 2, and its temperature continuously decreases, gradually being cooled into room-temperature, high-pressure saturated vapor, and further cooled into saturated liquid. Then, the saturated liquid refrigerant enters the first circuit switching device 8 and the second circuit switching device 12 respectively. The saturated liquid refrigerant flowing through channel B of the first circuit switching device 8 enters the first throttling device 3. After being throttled and depressurized by the first throttling device 3, it flows through the first evaporator 4, where it begins to absorb heat and vaporize, thereby lowering the temperature of the first evaporator 4 and its surroundings, turning the refrigerant into a low-temperature, low-pressure gas. Similarly, the saturated liquid refrigerant flowing through channel B of the second circuit switching device 12 enters the second throttling device 10. After being throttled and depressurized by the second throttling device 10, it flows through the second evaporator 9, where it begins to absorb heat and vaporize, thereby lowering the temperature of the second evaporator 9 and its surroundings, turning the refrigerant into a low-temperature, low-pressure gas. Then, the refrigerant exiting from the first evaporator 4 and the second evaporator 9 merges into the gas-liquid separator 5 and returns to the suction port of the compressor 1 to begin the next refrigeration cycle. This cycle repeats continuously, transferring heat from inside the refrigerator to the outside air, thus achieving the purpose of refrigeration.

[0103] In another alternative embodiment, the refrigerator further includes:

[0104] The second temperature detection device is installed on the second evaporator 9 and is used to detect the temperature of the second evaporator 9.

[0105] Then, the controller is further configured to:

[0106] When the temperature of the first evaporator 4 is detected to be greater than the preset temperature threshold, and / or the temperature of the second evaporator 9 is detected to be greater than the preset temperature threshold, the refrigerator is controlled to switch to cooling mode.

[0107] The defrosting control method for a refrigerator provided in this embodiment includes a compressor, a condenser, a first throttling device, a first evaporator, a gas-liquid separator, an oil circulation control device, a first bypass pipeline, and a first circuit switching device. The compressor, condenser, first throttling device, first evaporator, and gas-liquid separator are connected sequentially. The first end of the oil circulation control device is connected to the liquid outlet of the gas-liquid separator, and the second end of the oil circulation control device is connected to the pipeline between the compressor and the condenser. The first bypass pipeline is connected in parallel with the first throttling device. The first circuit switching device is connected to the condenser, the first throttling device, and the first bypass pipeline, respectively. The method includes:

[0108] When the refrigerator is in defrost mode, the compressor is controlled to shut down, the first circuit switching device is controlled to switch the condenser to be connected to the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separator to the condenser.

[0109] In the defrosting control method for a refrigerator provided in this embodiment, when the refrigerator is in defrosting mode, the oil separated by the gas-liquid separator is delivered to the condenser, allowing the oil to exchange heat with the condenser and its surrounding environment. After absorbing heat, the oil flows through the first bypass pipe to the first evaporator. Because the oil has a higher temperature after absorbing heat, it can heat the frost adhering to the surface of the first evaporator, melting the frost and achieving the purpose of defrosting. Simultaneously, since the specific heat capacity of the oil is much higher than that of the refrigerant, compared to the prior art, this embodiment can, on the one hand, utilize the oil to exchange more heat with the condenser and its surrounding environment to defrost the first evaporator, improving defrosting efficiency; on the other hand, it can also store a large amount of cold energy from the first evaporator, avoiding waste of cold energy during the defrosting process, thereby improving the refrigerator's cooling efficiency.

[0110] Furthermore, the method also includes:

[0111] When the refrigerator is in cooling mode, the compressor is turned on, the oil circulation control device is stopped from supplying oil to the condenser, and the first circuit switching device is switched to connect the condenser to the first throttling device.

[0112] In one specific embodiment, the refrigerator further includes a second evaporator, a second throttling device, a second bypass pipe, and a second circuit switching device; wherein, the first end of the second throttling device is connected to the pipe between the condenser and the first circuit switching device, and the second end of the second throttling device is connected to the pipe between the gas-liquid separator and the first evaporator through the second evaporator; the second bypass pipe is arranged in parallel with the second throttling device; the second circuit switching device is respectively connected to the condenser, the second throttling device, and the second bypass pipe; then, the method further includes:

[0113] The second circuit switching device is controlled to switch the condenser to be connected to the second bypass pipeline.

[0114] Furthermore, the method also includes:

[0115] When the refrigerator is in cooling mode, the compressor is turned on, the oil circulation control device is stopped supplying oil to the condenser, the first circuit switching device is switched to connect the condenser to the first throttling device, and the second circuit switching device is switched to connect the condenser to the second throttling device.

[0116] The specific description of the defrosting control method for the refrigerator provided in this embodiment can be found in the specific descriptions of the various embodiments of the refrigerator described above, and will not be repeated here.

[0117] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the device embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0118] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A refrigerator characterized by comprising: The refrigerator comprises: a refrigerant circulation loop comprising, in sequence, a compressor, a condenser, a first throttling device, a first evaporator and a gas-liquid separation device; wherein the gas-liquid separation device is connected to the first evaporator at an inlet thereof, and a gas outlet of the gas-liquid separation device is connected to the compressor; an oil circulation control device, a first end of which is connected to a liquid outlet of the gas-liquid separation device, and a second end of which is connected to a pipeline between the compressor and the condenser, for conveying oil in the gas-liquid separation device to the condenser when the refrigerator is in a defrost mode; a first bypass pipeline, which is arranged in parallel with the first throttling device; a first loop switching device, which is connected to the condenser, the first throttling device and the first bypass pipeline respectively, for switching the condenser to communicate with the first bypass pipeline or the first throttling device; a controller, configured to: control the compressor to be turned off, control the first loop switching device to switch the condenser to communicate with the first bypass pipeline, and control the oil circulation control device to convey oil in the gas-liquid separation device to the condenser when the refrigerator is in the defrost mode.

2. The refrigerator according to claim 1, wherein, The controller is further configured to: control the compressor to be turned on, control the oil circulation control device to stop conveying oil to the condenser, and control the first loop switching device to switch the condenser to communicate with the first throttling device when the refrigerator is in a refrigeration mode.

3. The refrigerator according to claim 1, wherein The oil circulation control device specifically comprises: an on-off valve, a first end of which is the first end of the oil circulation control device, and which is configured to be opened or closed under the control of the controller; an oil circulation pump, a first end of which is connected to a second end of the on-off valve, and a second end of which is the second end of the oil circulation control device, and which is configured to convey oil in the gas-liquid separation device to the condenser when the on-off valve is opened.

4. The refrigerator according to claim 1, wherein The refrigerator further comprises: a first temperature detection device, which is arranged on the first evaporator and is configured to detect a temperature of the first evaporator; The controller is further configured to: control the refrigerator to be switched to the refrigeration mode when it is detected that the temperature of the first evaporator is greater than a preset temperature threshold.

5. The refrigerator according to claim 1, wherein The refrigerator further comprises: a refrigerant circulation branch comprising a second evaporator and a second throttling device; wherein a first end of the second throttling device is connected to a pipeline between the condenser and the first loop switching device, and a second end of the second throttling device is connected to a pipeline between the gas-liquid separation device and the first evaporator through the second evaporator; a second bypass pipeline, which is arranged in parallel with the second throttling device; a second loop switching device, which is connected to the condenser, the second throttling device and the second bypass pipeline respectively, for switching the condenser to communicate with the second throttling device or the second bypass pipeline; The controller is further configured to: control the second loop switching device to switch the condenser to communicate with the second bypass pipeline when the refrigerator is in the defrost mode.

6. The refrigerator according to claim 5, wherein The controller is further configured to: When the refrigerator is in the defrosting mode, the compressor is controlled to be turned off, the first circuit switching device is controlled to switch the condenser to communicate with the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separation device to the condenser. 7.A control method of a refrigerator, characterized by, The refrigerator comprises a compressor, a condenser, a first throttling device, a first evaporator, a gas-liquid separation device, an oil circulation control device, a first bypass pipeline and a first circuit switching device; wherein the compressor, the condenser, the first throttling device, the first evaporator and the gas-liquid separation device are connected in sequence, a first end of the oil circulation control device is connected to a liquid outlet of the gas-liquid separation device, a second end of the oil circulation control device is connected to a pipeline between the compressor and the condenser, the first bypass pipeline is arranged in parallel with the first throttling device, and the first circuit switching device is connected with the condenser, the first throttling device and the first bypass pipeline respectively; the method comprises: When the refrigerator is in the defrosting mode, the compressor is controlled to be turned off, the first circuit switching device is controlled to switch the condenser to communicate with the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separation device to the condenser.

8. The control method of a refrigerator according to claim 7, characterized in that, The method further comprises: When the refrigerator is in the defrosting mode, the compressor is controlled to be turned off, the first circuit switching device is controlled to switch the condenser to communicate with the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separation device to the condenser.

9. The control method of a refrigerator according to claim 7, characterized in that, The refrigerator further comprises a second evaporator, a second throttling device, a second bypass pipeline and a second circuit switching device; wherein a first end of the second throttling device is connected to a pipeline between the condenser and the first circuit switching device, a second end of the second throttling device is connected to a pipeline between the gas-liquid separation device and the first evaporator through the second evaporator; the second bypass pipeline is arranged in parallel with the second throttling device; and the second circuit switching device is connected with the condenser, the second throttling device and the second bypass pipeline respectively; the method further comprises: The second circuit switching device is controlled to switch the condenser to communicate with the second bypass pipeline. 10.The control method of a refrigerator according to claim 9, characterized in that, The method further comprises: When the refrigerator is in the defrosting mode, the compressor is controlled to be turned off, the first circuit switching device is controlled to switch the condenser to communicate with the first bypass pipeline, and the oil circulation control device is controlled to deliver the oil in the gas-liquid separation device to the condenser.

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