Refrigerator and defrosting control method thereof

Abstract

The invention discloses a refrigerator and a defrosting control method of the refrigerator, and the defrosting control method comprises the following steps: a main refrigerating loop is used for discharging a refrigerant from an exhaust port of a compressor, conveying the refrigerant to a first interface of a first evaporator after passing through a condenser and a first capillary tube, and outputting the refrigerant to the compressor through a second interface to realize refrigerating cycle; a first interface of the two-position three-way electromagnetic valve is connected with an exhaust port of the compressor, a second interface of the two-position three-way electromagnetic valve is connected with a first interface of the first evaporator, and a third interface of the two-position three-way electromagnetic valve is connected with an air inlet of the The auxiliary refrigeration branch comprises a second capillary tube and a second evaporator; an inlet of the second capillary tube is connected with a first interface of the first evaporator and outputs a refrigerant to the compressor through the second evaporator; and the controller is configured to control the first interface of the two-position three-way electromagnetic valve to be connected to the second interface and close the third interface when the refrigerator enters a defrosting mode. According to the scheme, the defrosting efficiency is high, energy consumption is low, and meanwhile the influence on the refrigerating temperature of the refrigerator compartment is small.

Description

Technical Field

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

[0002] In the refrigeration system of a refrigerator, the refrigerant undergoes continuous refrigeration cycles and continuously exchanges heat with air on the surface of the evaporator. The low temperature causes frosting, which hinders the conduction and dissipation of the cold of the refrigeration evaporator, affects the refrigeration effect, causes a large waste of electric energy, and shortens the service life of the refrigeration system. Therefore, it is necessary to perform defrosting operations in the refrigerator at appropriate intervals. The purpose of defrosting is to improve the refrigeration efficiency of the system, ensure the quality of frozen products in the warehouse, save electric energy, and extend the service life of the refrigerator system.

[0003] The evaporator usually performs defrosting operations by means of configured electric heating. However, the electric heating defrosting method has the disadvantages of low defrosting efficiency and high energy consumption, and the defrosting process will cause a significant rise in the refrigeration temperature of the refrigerator compartment, affecting the working performance of the refrigerator. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a refrigerator and a defrosting control method for a refrigerator. The solution of the present application has high defrosting efficiency, low energy consumption, and little impact on the refrigeration temperature of the refrigerator compartment.

[0005] To achieve the above purpose, the embodiments of the present invention provide a refrigerator, including:

[0006] A main refrigeration circuit, which supplies the refrigerant to be discharged from the exhaust port of the compressor, passes through the condenser and the first capillary tube, and then is transported to the first interface of the first evaporator, and the refrigerant is output from the second interface of the first evaporator to the intake port of the compressor to achieve a refrigeration cycle;

[0007] A two-position three-way solenoid valve, whose first interface is connected to the exhaust port of the compressor, whose second interface is connected to the first interface of the first evaporator, and whose third interface is connected to the intake port of the compressor;

[0008] A secondary refrigeration branch, which includes a second capillary tube and a second evaporator; the inlet of the second capillary tube is connected to the first interface of the first evaporator, and the inlet of the second capillary tube outputs the refrigerant to the intake port of the compressor through the second evaporator;

[0009] A controller;

[0010] The controller is configured to:

[0011] When the refrigerator enters the defrosting mode, control the first interface of the two-position three-way solenoid valve to connect to the second interface and close the third interface.

[0012] Preferably, the controller is further configured to:

[0013] When the refrigerator enters the refrigeration mode, control the second interface of the two-way three-way solenoid valve to connect to the third interface, and close the second interface.

[0014] Furthermore, the refrigerator further includes:

[0015] A temperature sensor for detecting the current temperature of the first evaporator;

[0016] The controller is further configured to:

[0017] After power-on, start the refrigerator in the refrigeration mode and detect the current temperature of the first evaporator;

[0018] When the detected current temperature is not higher than a preset defrost temperature threshold, control the refrigerator to enter the defrost mode, calculate the operation duration of the defrost mode and continue to detect the current temperature;

[0019] When the operation duration is not less than a preset duration threshold and the currently detected current temperature is higher than the defrost temperature threshold, control the refrigerator to enter the refrigeration mode.

[0020] As a preferred solution, the refrigerator further includes:

[0021] A regenerator for realizing heat exchange between the first capillary tube and the suction pipe of the compressor; the inlet of the suction pipe is respectively connected to the third interface of the two-way three-way solenoid valve and the outlet of the second evaporator, and the outlet of the suction pipe is connected to the inlet of the compressor.

[0022] Preferably, the first evaporator is an air-cooled finned tube evaporator;

[0023] The refrigerator ventilates the freezer and the refrigerator compartment of the refrigerator through the configured air ducts and air doors respectively.

[0024] Preferably, the second capillary tube is a direct-cooling capillary tube:

[0025] The second evaporator is a direct-cooling evaporator.

[0026] Furthermore, the second evaporator is arranged on the back of the inner wall of the storage compartment on the side;

[0027] The second evaporator adopts an evaporation coil with a pipe diameter of 4 mm.

[0028] An embodiment of the present invention further provides a defrost control method for a refrigerator, and the refrigerator includes:

[0029] A main refrigeration circuit, where refrigerant is discharged from the exhaust port of a compressor, transported to a first interface of a first evaporator via a condenser and a first capillary tube, and the refrigerant is output from a second interface of the first evaporator to an intake port of the compressor to achieve a refrigeration cycle;

[0030] A two-way three-way solenoid valve, whose first interface is connected to the exhaust port of the compressor, whose second interface is connected to the first interface of the first evaporator, and whose third interface is connected to the intake port of the compressor;

[0031] A secondary refrigeration branch, which includes a second capillary tube and a second evaporator; an inlet of the second capillary tube is connected to the first interface of the first evaporator, and the refrigerant is output from the inlet of the second capillary tube to the intake port of the compressor through the second evaporator;

[0032] A controller;

[0033] The method includes:

[0034] When the refrigerator enters a defrosting mode, connect the first interface of the two-way three-way solenoid valve to the second interface and close the third interface.

[0035] Preferably, the method further includes:

[0036] When the refrigerator enters a refrigeration mode, connect the second interface of the two-way three-way solenoid valve to the third interface and close the second interface.

[0037] Furthermore, the refrigerator further includes:

[0038] A temperature sensor for detecting the current temperature of the first evaporator;

[0039] The method further includes:

[0040] After power-on, start the refrigerator in the refrigeration mode and detect the current temperature of the first evaporator;

[0041] When the detected current temperature is not higher than a preset defrosting temperature threshold, control the refrigerator to enter the defrosting mode, calculate the operation duration of the defrosting mode and continue to detect the current temperature;

[0042] When the operation duration is not less than a preset duration threshold and the currently detected current temperature is higher than the defrosting temperature threshold, control the refrigerator to enter the refrigeration mode.

[0043] Compared with the prior art, the refrigerator and the defrosting control method of the refrigerator disclosed in the present invention include: a main refrigeration circuit for discharging refrigerant from the exhaust port of a compressor, delivering it to a first interface of a first evaporator via a condenser and a first capillary tube, and outputting the refrigerant from a second interface of the first evaporator to an intake port of the compressor to achieve a refrigeration cycle; a two-way three-way solenoid valve, whose first interface is connected to the exhaust port of the compressor, whose second interface is connected to the first interface of the first evaporator, and whose third interface is connected to the intake port of the compressor; a secondary refrigeration branch including a second capillary tube and a second evaporator; an inlet of the second capillary tube is connected to the first interface of the first evaporator, and the inlet of the second capillary tube outputs the refrigerant to the intake port of the compressor through the second evaporator; a controller; the controller is configured to: when the refrigerator enters a defrosting mode, control the first interface of the two-way three-way solenoid valve to connect to the second interface and close the third interface. The solution of this application has high defrosting efficiency, low energy consumption, and little impact on the refrigeration temperature of the refrigerator compartment. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 FIG. 6 is a schematic diagram of the external structure of a refrigerator 100 provided by an embodiment of the present invention;

[0045] Figure 2 FIG. 10 is a schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention;

[0046] Figure 3 FIG. 14 is a schematic diagram of the structure of a refrigeration system in a refrigerator provided by an embodiment of the present invention;

[0047] Figure 4 FIG. 18 is a schematic diagram of the structure of a refrigerator provided by an embodiment of the present invention;

[0048] Figure 5 FIG. 22 is a schematic diagram of the connection relationship between a refrigerator provided by an embodiment of the present invention and other devices;

[0049] Figure 6 FIG. 26 is a schematic flowchart of the steps executed by a controller provided by an embodiment of the present invention;

[0050] Figure 7 FIG. 30 is a schematic diagram of the refrigerant flow direction of a hot gas defrosting circuit of a refrigerator provided by an embodiment of the present invention;

[0051] Figure 8 FIG. 34 is a schematic diagram of the refrigerant flow direction of a refrigeration circuit of a refrigerator provided by an embodiment of the present invention;

[0052] Figure 9 FIG. 38 is a schematic diagram of another structure of a refrigerator provided by an embodiment of the present invention;

[0053] Figure 10It is another schematic flow chart of the steps executed by the controller provided in the embodiments of the present invention. Detailed implementation manners

[0054] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0055] In the description of the present 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 drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0056] The terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0057] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0058] See Figure 1 , Figure 1FIG. 0 is a schematic diagram of the external structure of a refrigerator 100 provided by an embodiment of the present invention. The refrigerator 100 in this embodiment has an approximate cuboid shape. The refrigerator includes a box body defining a storage space and a plurality of door bodies provided at the opening of the box body. Among them, the door body includes a door body outer shell located outside the box body, a door body inner liner located inside the box body, an upper end cover, a lower end cover, and a heat insulation layer located between the door body outer shell, the door body inner liner, the upper end cover, and the lower end cover. Generally, the heat insulation layer is filled with foaming material. The box body is provided with a chamber, and the chamber includes a component storage chamber for placing components in the refrigerator, such as a compressor compartment, etc., and also includes a storage space for storing food, etc.

[0059] See Figure 2 , FIG. 5 is a schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention. The storage space can be divided into a plurality of storage compartments. According to different uses, the storage compartments can be configured as a refrigerating compartment and a freezing compartment, and can also include a variable temperature compartment, a vacuum drawer, a humidity-preserving drawer, and so on. Each storage compartment corresponds to one or more door bodies. For example, in Figure 2 , the upper storage compartment is provided with a double-door body. Among them, the door body can be pivotally provided at the opening of the box body, or can also be opened in a drawer manner to achieve drawer-type storage. A display screen is provided at the door of the refrigerator, and the display screen is used to display prompt information and receive touch operations of the user.

[0060] See Figure 3, is a schematic diagram of the structure of the refrigeration system in the refrigerator provided by an embodiment of the present invention, wherein the refrigeration system comprises a compressor 101, an evaporator 2, a drying filter (not shown in the figure), a capillary tube 3, a condenser 102 and a gas-liquid separator (not shown in the figure). The working process of the refrigeration system comprises a compression process, a condensation process, a throttling process and an evaporation process. Among them, the compression process is: plug in the power cord of the refrigerator, when the contacts of the thermostat are connected, the compressor 101 starts to work, the low-temperature and low-pressure refrigerant is sucked into the compressor 101, and is compressed into a high-temperature and high-pressure superheated gas in the cylinder of the compressor 101 and then discharged into the condenser 102; the condensation process is: the high-temperature and high-pressure refrigerant gas dissipates heat through the condenser 102, the temperature continues to drop, and is gradually cooled to a saturated vapor of normal temperature and high pressure, and is further cooled to a saturated liquid, and the temperature no longer drops. The temperature at this time is called the condensation temperature, and the pressure of the refrigerant is almost constant during the entire condensation process. The throttling process is as follows: the condensed saturated refrigerant liquid is filtered through a drying filter to remove moisture and impurities and then flows into the capillary 3, through which throttling and pressure reduction are performed, and the refrigerant becomes wet steam at room temperature and low pressure; the evaporation process is as follows: the wet steam at room temperature and low pressure begins to absorb heat and vaporize in the evaporator 2, which not only reduces the temperature of the evaporator 2 and its surroundings, but also turns the refrigerant into a low-temperature and low-pressure gas. The refrigerant coming out of the evaporator 2 passes through the gas-liquid separator and then returns to the compressor 101, and the above process is repeated to transfer the heat in the refrigerator to the air outside the box, thereby achieving the purpose of refrigeration.

[0061] The refrigerator provided in the embodiment of the present invention comprises:

[0062] A main refrigeration circuit, wherein the refrigerant is discharged from the exhaust port of the compressor, transported to the first interface of the first evaporator through the condenser and the first capillary tube, and the refrigerant is output to the air inlet of the compressor through the second interface of the first evaporator to realize a refrigeration cycle;

[0063] A two-position three-way solenoid valve, wherein a first interface thereof is connected to the exhaust port of the compressor, a second interface thereof is connected to the first interface of the first evaporator, and a third interface thereof is connected to the air inlet of the compressor;

[0064] A secondary refrigeration branch, comprising a second capillary tube and a second evaporator; the inlet of the second capillary tube is connected to the first interface of the first evaporator, and the inlet of the second capillary tube outputs the refrigerant to the air inlet of the compressor through the second evaporator;

[0065] Controller;

[0066] The controller is configured to:

[0067] When the refrigerator enters the defrost mode, the first interface of the two-position three-way solenoid valve is controlled to be connected to the second interface, and the third interface is closed.

[0068] In specific implementation, refer to Figure 4 , which is a schematic structural diagram of the refrigerator provided by the embodiment of the present invention. The refrigeration circuit of the refrigerator includes a compressor 101, a condenser 102, a first capillary tube 108, a first evaporator 106, a two-way three-way solenoid valve 107, a second capillary tube 104, and a second evaporator 105.

[0069] The exhaust port of the compressor is connected to the refrigerant inlet of the first capillary tube 108 through a pipeline, and the refrigerant outlet of the first capillary tube 108 is divided into two paths through a pipeline.

[0070] The first path is connected to the main refrigeration branch. The refrigerant outlet of the first capillary tube 108 is connected to the first interface of the first evaporator 106 through a pipeline. The second interface of the first evaporator 106 is connected to the second interface B of the two-way three-way solenoid valve 107 through a pipeline. The third interface C of the two-way three-way solenoid valve 107 is connected to the intake port of the compressor 101 through a pipeline. Through the first path, the refrigerant is discharged from the exhaust port of the compressor, and after passing through the condenser and the first capillary tube, it is transported to the first interface of the first evaporator, and the refrigerant is output to the intake port of the compressor through the two-way three-way solenoid valve at the second interface of the first evaporator, forming a main refrigeration circuit to realize the refrigeration cycle. The storage compartment in the refrigerator is cooled through the first evaporator to achieve.

[0071] The second path is used to connect the auxiliary refrigeration branch. The refrigerant outlet of the first capillary tube 108 is also connected to the inlet of the second capillary tube 104 through a pipeline. The outlet of the second capillary tube 104 is connected to the inlet of the second evaporator 105 through a pipeline. The outlet of the second evaporator 105 is connected to the intake port of the compressor 101 through a pipeline.

[0072] The first interface A of the two-way three-way solenoid valve 107 is connected to the exhaust port of the compressor 101.

[0073] The refrigerator further includes a controller 10. The controller 10 in the refrigerator is not only used to execute corresponding control functions during the normal operation of the refrigerator, but in this application, the controller 10 is used for defrosting control. Refer to Figure 5 , which is a schematic structural diagram of the connection relationship between the refrigerator provided by the embodiment of the present invention and other devices.

[0074] The controller 10 is connected to the two-way three-way solenoid valve 107 and is used to control the position state of the two-way three-way solenoid valve 107.

[0075] In the embodiment of the present invention, refer to Figure 6 , which is a schematic flowchart of the steps executed by the controller provided by the embodiment of the present invention. The controller 10 can respond to a preset defrosting control instruction and execute the defrosting control operation of the refrigerator, specifically including the following steps:

[0076] Step S601, the refrigerator is powered on and operates.

[0077] Step S602, determine whether the refrigerator enters the defrosting mode.

[0078] If not, return to Step S602.

[0079] If so, execute Step S603.

[0080] Step S603, control the first interface of the two-way three-way solenoid valve to connect to the second interface and close the third interface.

[0081] Specifically, when the refrigerator needs to defrost, at this time, connect the first interface A to the second interface B and close the third interface to penetrate the hot gas defrosting circuit of the refrigeration cycle system.

[0082] At this time, referring to Figure 7 , it is a schematic diagram of the refrigerant flow direction of the hot gas defrosting circuit of the refrigerator provided by the embodiment of the present invention.

[0083] In the defrosting mode, most of the hot gas discharged from the exhaust port of the compressor 101 is transported to the first interface A of the two-way three-way solenoid valve 107 and is transported to the first evaporator 106 via the second interface B of the two-way three-way solenoid valve. At this time, the first evaporator 106 is used for condensation. The condensation of most of the bypass hot gas discharged from the compressor 101 in the first evaporator 106 realizes the rapid melting of the frost on the outer tube and the recovery of cold energy. Therefore, the frost on the first evaporator can be quickly defrosted. The high-temperature refrigerant output by the compressor is gradually cooled to normal temperature and high-pressure saturated vapor after passing through the first evaporator, and is further cooled to saturated liquid, and the temperature no longer drops. The temperature at this time is called the condensation temperature. The pressure of the refrigerant is almost unchanged during the entire condensation process. The first evaporator transports the refrigerant to the inlet of the second capillary 104, and the refrigerant is throttled and depressurized through the second capillary, and the refrigerant becomes normal temperature and low-pressure wet vapor; then it passes through the second evaporator; the normal temperature and low-pressure wet vapor starts to absorb heat and vaporize in the second evaporator, which not only reduces the temperature of the second evaporator and its surrounding area, but also turns the refrigerant into low-temperature and low-pressure gas. The refrigerant coming out of the second evaporator returns to the compressor 101 again, repeating the above process to complete the defrosting of the first evaporator of the main refrigeration circuit of the refrigerator, and maintain the refrigeration of the refrigerator through the second capillary and the second evaporator.

[0084] It should be noted that in the defrosting mode, a small part of the hot gas discharged from the compressor 101 still enters the condenser and the first capillary, and then enters the second capillary and the second evaporator, enhancing the refrigeration capacity of the second evaporator for the storage compartment.

[0085] The refrigerator provided by this application adopts a hot gas bypass circuit, which can not only significantly improve the defrosting speed and efficiency, realize the defrosting function and recover the cold quantity of the frost, but also utilize the second capillary tube 104 and the second evaporator to recover the cold quantity of the frost for refrigerating the refrigerating chamber, effectively avoiding the problem of temperature rise in the refrigerating chamber.

[0086] In another embodiment provided by the present invention, the controller is further configured to:

[0087] When the refrigerator enters the refrigeration mode, control the second interface of the two-way three-way solenoid valve to connect to the third interface and close the second interface.

[0088] When specifically implementing this embodiment, refer to Figure 6 , the controller 10 can respond to a preset defrost control instruction, execute the defrost control operation of the refrigerator, and can also return from the defrost mode to the refrigeration mode according to the refrigeration execution. Specifically, the following steps are further executed:

[0089] Step S604, determine whether the refrigerator enters the refrigeration mode;

[0090] If not, return to step S604;

[0091] If so, execute step S605;

[0092] Step S605, control the second interface of the two-way three-way solenoid valve to connect to the third interface and close the second interface.

[0093] Specifically, when the refrigerator exits the defrost mode and enters the normal refrigeration mode, at this time, connect the second interface B and the third interface C, close the first interface, and penetrate the refrigeration circuit of the refrigeration cycle system.

[0094] At this time, refer to Figure 8 , which is a schematic diagram of the refrigerant flow direction of the refrigeration circuit of the refrigerator provided by the embodiment of the present invention.

[0095] In the refrigeration mode, the hot gas discharged from the exhaust port of the compressor 101 is transported to the condenser 102. The high-temperature refrigerant output by the compressor is gradually cooled to normal temperature and high-pressure saturated vapor through the condenser 102, and further cooled to saturated liquid, and the temperature no longer drops. At this time, the temperature is called the condensation temperature. The pressure of the refrigerant hardly changes during the entire condensation process. The condenser transports the refrigerant to the inlet of the first capillary tube 108, and the refrigerant becomes normal temperature and low-pressure wet vapor after throttling and pressure reduction through the first capillary tube; and then passes through the first evaporator; the normal temperature and low-pressure wet vapor starts to absorb heat and vaporize in the first evaporator, not only reducing the temperature of the first evaporator and its surrounding area, but also turning the refrigerant into low-temperature and low-pressure gas. The refrigerant coming out of the first evaporator returns to the compressor 101 through the two-way three-way solenoid valve again, repeating the above process to complete the refrigeration of the refrigerator.

[0096] It should be noted that in the refrigeration mode, the refrigerant output by the first capillary tube is also delivered to the inlet of the second capillary tube 104, throttled and depressurized through the second capillary tube, and then passes through the second evaporator; the refrigerant coming out of the second evaporator returns to the compressor 101 again, repeating the above process. Through the further throttling of the second capillary tube and the auxiliary refrigeration effect of the second evaporator, the refrigeration performance of the refrigerator can be improved.

[0097] In the refrigeration mode, the first evaporator is used to maintain the refrigeration of the refrigerator, and the second evaporator is used for auxiliary refrigeration to improve the refrigeration performance of the refrigerator.

[0098] In another embodiment provided by the present invention, the refrigerator further includes:

[0099] A temperature sensor for detecting the current temperature of the first evaporator;

[0100] The controller is further configured to:

[0101] After being powered on, start the refrigerator in the refrigeration mode and detect the current temperature of the first evaporator;

[0102] When the detected current temperature is not higher than the preset defrost temperature threshold, control the refrigerator to enter the defrost mode, calculate the running duration of the defrost mode and continue to detect the current temperature;

[0103] When the running duration is not less than the preset duration threshold and the currently detected current temperature is higher than the defrost temperature threshold, control the refrigerator to enter the refrigeration mode.

[0104] When specifically implementing this embodiment, refer to Figure 9 , which is another schematic structural diagram of the refrigerator provided by the embodiment of the present invention; the refrigerator further includes a temperature sensor 110, and the first temperature sensor is arranged on the coil of the evaporator for detecting the current temperature T of the evaporator coil.

[0105] Refer to Figure 5 , the controller 10 is also connected to the temperature sensor 110 for obtaining the current temperature T and performing defrost control according to the current temperature.

[0106] Refer to Figure 10 , which is another schematic flow diagram of the steps executed by the controller provided by the embodiment of the present invention. The controller 10 is used to execute the following steps:

[0107] Step S1001, after being powered on, start the refrigerator in the refrigeration mode;

[0108] Step S1002, detect the current temperature T of the first evaporator;

[0109] Step S1003, determine whether the current temperature T ≤ T th holds. That is, determine whether the current temperature is not higher than the preset defrost temperature threshold T th .

[0110] If not, return to step S1003. That is, when the current temperature T of the refrigerator does not meet the entry condition of the defrost mode, continue to detect the current temperature T of the refrigerator until the entry condition of the defrost mode is met.

[0111] If so, execute step S1004;

[0112] Step S1004, enter the defrost mode.

[0113] Step S1005, calculate the running duration t of the defrost mode;

[0114] Step S1006, determine whether the running duration t ≥ t1 holds. That is, determine whether the running duration t is not lower than the preset duration threshold t1.

[0115] If so, execute step S1007;

[0116] If not, return to step S1005;

[0117] Step S1007, detect the current temperature T;

[0118] Step S1008, determine whether the current temperature T ≤ T th holds. That is, determine whether the current temperature is not higher than the preset defrost temperature threshold T th .

[0119] If so, return to step S1007. That is, when the current temperature T of the refrigerator does not meet the entry condition of the refrigeration mode, continue to detect the current temperature T of the refrigerator until the entry condition of the refrigeration mode is met.

[0120] If not, execute step S1009;

[0121] Step S1009, enter the refrigeration mode.

[0122] Under the initial condition, the refrigerator automatically enters the refrigeration mode, detects the current temperature of the coil, determines whether to enter the defrost mode. After entering the defrost mode, detects the running duration of the defrost mode and the current temperature of the coil, and comprehensively determines whether the defrosting is completed, avoiding the situation that when only detecting the current temperature, due to the rapid temperature rise of the first evaporator, the defrosting is misjudged to be completed, resulting in incomplete defrosting.

[0123] In another embodiment provided by the present invention, the refrigerator further includes:

[0124] A regenerator, which is used to realize the heat exchange between the first capillary tube and the suction pipe of the compressor; the inlet of the suction pipe is respectively connected to the third interface of the two-way three-way solenoid valve and the outlet of the second evaporator, and the outlet of the suction pipe is connected to the air inlet of the compressor.

[0125] See Figure 9 , the refrigerator provided by the present invention further includes a regenerator 103, and the regenerator is used to realize the heat exchange between the first capillary tube 108 and the suction pipe 109 of the compressor. The regenerator 103 combines the first capillary tube 108 and the suction pipe 109 of the compressor together, so that the two can fully perform heat exchange. Since the refrigerant in the compressor suction pipe is a low-temperature gas flowing from the first evaporator or the second evaporator, the temperature of the refrigerant in the first capillary tube can be further decreased, and at the same time, the temperature of the refrigerant in the compressor suction pipe can be further increased. This is the heat regeneration cycle.

[0126] Through the heat regeneration cycle of the regenerator, not only can more liquid refrigerant be liquefied in the first capillary tube, but also the residual liquid refrigerant from the first evaporator or the second evaporator in the compressor suction pipe can be completely evaporated, so as to prevent liquid refrigerant from returning to the compressor and causing liquid hammer phenomenon.

[0127] In another embodiment provided by the present invention, the first evaporator is an air-cooled finned tube evaporator;

[0128] The refrigerator ventilates the freezer and the refrigerator compartment of the refrigerator through the configured air ducts and air doors respectively.

[0129] When this embodiment is specifically implemented, the refrigerator of the present application is a single-stage vapor compression refrigeration system, and usually an air-cooled finned tube evaporator is used for refrigeration. The air-cooled finned tube evaporator accelerates the air flow through a fan and transmits the cold quantity to the storage compartment of the refrigerator.

[0130] The refrigerator storage compartment generally includes a freezer and a refrigerator compartment. The air duct configured by an air-cooled finned tube evaporator is used to transmit the cold quantity, and air doors are respectively configured in the refrigerator compartment and the freezer to control the rate of entering the refrigerator compartment and the freezer, and further control the temperatures of the refrigerator compartment and the freezer.

[0131] In another embodiment provided by the present invention, the second capillary tube is a direct-cooling capillary tube:

[0132] The second evaporator is a direct-cooling evaporator.

[0133] When this embodiment is specifically implemented, a direct direct-cooling method can be adopted for the second capillary tube and the second evaporator.

[0134] The refrigeration evaporator, i.e., the direct cooling evaporator, is an evaporator for cooling the air coolant. The refrigerant absorbs heat and evaporates inside the tubes of the evaporator, thereby reducing the temperature of the air outside the tubes. According to the reason for the air flow, the refrigerant flows inside the tube rows, absorbs the heat of the surrounding air and vaporizes, and relies on the thermal pressure of the air for natural convection to reduce the temperature inside the refrigerator. In addition, expandable fins are used to increase the heat transfer area, enhance the air disturbance, and improve the heat transfer efficiency of the evaporator.

[0135] In another embodiment provided by the present invention, the second evaporator is arranged at the back of the inner wall of the box on the side of the storage compartment.

[0136] The second evaporator uses an evaporation coil with a pipe diameter of 4 mm.

[0137] In the specific implementation of this embodiment, the second evaporator 105 is of the plate-tube type and can be arranged at the back of the inner wall of the side of the refrigerating compartment of the air-cooled refrigerator, so as to realize the auxiliary direct cooling function of the refrigerating compartment; the second evaporator 105 includes a small-diameter evaporation coil (with a pipe diameter of 4 mm) and an aluminum plate or a copper plate.

[0138] In the refrigeration mode, the second evaporator 105 also has an auxiliary direct cooling effect. However, due to the use of a small-diameter evaporation coil and a direct cooling capillary tube, the refrigerant flow rate is small and the refrigerating capacity is also very small, so as to maintain the refrigerating capacity of the first evaporator.

[0139] The embodiment of the present invention also provides a defrosting control method for a refrigerator, which is applied to a refrigerator, and the refrigerator includes:

[0140] A main refrigeration circuit, in which the refrigerant is discharged from the exhaust port of the compressor, passes through the condenser and the first capillary tube, and then is delivered to the first interface of the first evaporator, and the refrigerant is output from the second interface of the first evaporator to the intake port of the compressor to realize the refrigeration cycle;

[0141] A two-position three-way solenoid valve, whose first interface is connected to the exhaust port of the compressor, whose second interface is connected to the first interface of the first evaporator, and whose third interface is connected to the intake port of the compressor;

[0142] A secondary refrigeration branch, which includes a second capillary tube and a second evaporator; the inlet of the second capillary tube is connected to the first interface of the first evaporator, and the refrigerant is output from the inlet of the second capillary tube to the intake port of the compressor through the second evaporator;

[0143] A controller;

[0144] The method includes:

[0145] When the refrigerator enters the defrosting mode, connect the first interface of the two-position three-way solenoid valve to the second interface and close the third interface.

[0146] In the defrost mode, most of the hot gas discharged from the exhaust port of the compressor 101 is delivered to the first interface A of the two-way three-way solenoid valve 107, and then delivered to the first evaporator 106 via the second interface B of the two-way three-way solenoid valve. At this time, the first evaporator 106 functions as a condenser. The condensation of most of the bypass hot gas discharged from the compressor 101 in the first evaporator 106 enables the rapid melting of the frost on the outer tube and the recovery of cold energy. Therefore, the frost on the first evaporator can be defrosted quickly. The high-temperature refrigerant output by the compressor is gradually cooled to normal temperature and high-pressure saturated vapor through the first evaporator, and further cooled to saturated liquid, and the temperature no longer drops. The temperature at this time is called the condensation temperature. The pressure of the refrigerant remains almost unchanged during the entire condensation process. The first evaporator delivers the refrigerant to the inlet of the second capillary tube 104, and the refrigerant is throttled and depressurized through the second capillary tube, and the refrigerant becomes normal temperature and low-pressure wet vapor; then it passes through the second evaporator; the normal temperature and low-pressure wet vapor starts to absorb heat and vaporize in the second evaporator, which not only reduces the temperature of the second evaporator and its surroundings, but also turns the refrigerant into low-temperature and low-pressure gas. The refrigerant coming out of the second evaporator returns to the compressor 101 again, repeating the above process to complete the defrosting of the first evaporator of the refrigerator's refrigeration circuit, and maintaining the refrigeration of the refrigerator through the second capillary tube and the second evaporator.

[0147] The refrigerator provided by this application adopts a hot gas bypass circuit, which can not only significantly improve the defrosting speed and efficiency, realize the defrosting function and recover the cold energy of the frost, but also utilize the second capillary tube 1 and the second evaporator to recover the cold energy of the frost for the refrigeration of the refrigerating chamber, effectively avoiding the problem of temperature rise in the refrigerating chamber.

[0148] In another embodiment provided by the present invention, the method further includes:

[0149] When the refrigerator enters the refrigeration mode, connect the second interface of the two-way three-way solenoid valve to the third interface and close the second interface.

[0150] In the refrigeration mode, the hot gas discharged from the exhaust port of the compressor 101 is delivered to the condenser 102. The high-temperature refrigerant output by the compressor is gradually cooled to normal-temperature and high-pressure saturated vapor through the condenser 102, and further cooled to saturated liquid, and the temperature no longer drops. The temperature at this time is called the condensation temperature. The pressure of the refrigerant remains almost unchanged during the entire condensation process. The condenser delivers the refrigerant to the inlet of the first capillary tube 108, and the refrigerant is throttled and depressurized through the first capillary tube, and the refrigerant becomes normal-temperature and low-pressure wet vapor; then it passes through the first evaporator; the normal-temperature and low-pressure wet vapor starts to absorb heat and vaporize in the first evaporator, not only reducing the temperature of the first evaporator and its surroundings, but also turning the refrigerant into low-temperature and low-pressure gas. The refrigerant coming out of the first evaporator returns to the compressor 101 again through the two-way three-way solenoid valve, repeating the above process to complete the refrigeration of the refrigerator.

[0151] It should be noted that in the refrigeration mode, through the further throttling of the second capillary tube and the auxiliary refrigeration effect of the second evaporator, the refrigeration performance of the refrigerator can be improved.

[0152] In the refrigeration mode, the first evaporator is used to maintain the refrigeration of the refrigerator, and the second evaporator is used for auxiliary refrigeration to improve the refrigeration performance of the refrigerator.

[0153] In another embodiment provided by the present invention, the refrigerator further includes:

[0154] A temperature sensor for detecting the current temperature of the first evaporator;

[0155] The method further includes:

[0156] After power-on, start the refrigerator in the refrigeration mode and detect the current temperature of the first evaporator;

[0157] When the detected current temperature is not higher than the preset defrost temperature threshold, control the refrigerator to enter the defrost mode, calculate the operation duration of the defrost mode and continue to detect the current temperature;

[0158] When the operation duration is not less than the preset duration threshold and the currently detected current temperature is higher than the defrost temperature threshold, control the refrigerator to enter the refrigeration mode.

[0159] Under the initial conditions, the refrigerator automatically enters the refrigeration mode, detects the current temperature of the coil, judges whether to enter the defrost mode. After entering the defrost mode, detects the operation duration of the defrost mode and the current temperature of the coil, and comprehensively judges whether the defrost is completed, avoiding the situation that when only detecting the current temperature, due to the rapid temperature rise of the first evaporator, the defrost is misjudged as completed, resulting in incomplete defrost.

[0160] It should be noted that the defrosting control method of a refrigerator provided by an embodiment of the present invention is the same as all the process steps executed by the controller of a refrigerator in the above embodiment, and the working principles and beneficial effects of the two correspond one by one, so they will not be elaborated here.

[0161] Those of ordinary skill in the art can understand that all or part of the processes in the above-described method embodiments can be implemented by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the method embodiments as described above. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc.

[0162] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A refrigerator, characterized in that, Comprising: A main refrigeration circuit, which supplies refrigerant discharged from the exhaust port of a compressor, transports it to the first interface of a first evaporator after passing through a condenser and a first capillary tube, and outputs the refrigerant from the second interface of the first evaporator to the intake port of the compressor to achieve a refrigeration cycle; A two-way three-way solenoid valve, whose first interface is connected to the exhaust port of the compressor, whose second interface is connected to the first interface of the first evaporator, and whose third interface is connected to the intake port of the compressor; A secondary refrigeration branch, which includes a second capillary tube and a second evaporator; The inlet of the second capillary tube is connected to the first interface of the first evaporator, and the inlet of the second capillary tube outputs the refrigerant to the intake port of the compressor through the second evaporator; A controller; The controller is configured to: When the refrigerator enters the defrosting mode, control the first interface of the two-way three-way solenoid valve to connect to the second interface and close the third interface.

2. The refrigerator according to claim 1, wherein, The controller is further configured to: When the refrigerator enters the refrigeration mode, control the second interface of the two-way three-way solenoid valve to connect to the third interface and close the second interface.

3. The refrigerator according to claim 2, characterized in that, The refrigerator further includes: A temperature sensor for detecting the current temperature of the first evaporator; The controller is further configured to: After power-on, start the refrigerator in the refrigeration mode and detect the current temperature of the first evaporator; When the detected current temperature is not higher than a preset defrosting temperature threshold, control the refrigerator to enter the defrosting mode, calculate the running duration of the defrosting mode and continue to detect the current temperature; When the running duration is not less than a preset duration threshold and the currently detected current temperature is higher than the defrosting temperature threshold, control the refrigerator to enter the refrigeration mode.

4. The refrigerator according to claim 1, characterized in that, The refrigerator further includes: A regenerator for realizing heat exchange between the first capillary tube and the suction pipe of the compressor; the inlet of the suction pipe is respectively connected to the third interface of the two-way three-way solenoid valve and the outlet of the second evaporator, and the outlet of the suction pipe is connected to the intake port of the compressor.

5. The refrigerator according to claim 1, characterized in that, The first evaporator is an air-cooled finned tube evaporator; The refrigerator ventilates the freezer and the refrigerator compartment of the refrigerator through a configured air duct and an air door respectively.

6. The refrigerator according to claim 1, characterized in that, The second capillary tube is a direct-cooling capillary tube: The second evaporator is a direct-cooling evaporator.

7. The refrigerator according to claim 6, characterized in that, The second evaporator is arranged on the back of the inner wall of the box on the side of the storage compartment; The second evaporator adopts an evaporation coil with a pipe diameter of 4 mm.

8. A defrost control method for a refrigerator, characterized in that, The refrigerator includes: A main refrigeration circuit, which supplies refrigerant discharged from the exhaust port of a compressor, transports it to the first interface of a first evaporator after passing through a condenser and a first capillary tube, and outputs the refrigerant from the second interface of the first evaporator to the intake port of the compressor to achieve a refrigeration cycle; A two-way three-way solenoid valve, whose first interface is connected to the exhaust port of the compressor, whose second interface is connected to the first interface of the first evaporator, and whose third interface is connected to the intake port of the compressor; A secondary refrigeration branch, which includes a second capillary tube and a second evaporator; the inlet of the second capillary tube is connected to the first interface of the first evaporator, and the inlet of the second capillary tube outputs the refrigerant to the intake port of the compressor through the second evaporator; A controller; The method includes: When the refrigerator enters the defrosting mode, connect the first interface of the two-way three-way solenoid valve to the second interface and close the third interface.

9. The defrosting control method of the refrigerator according to claim 8, characterized in that, The method further includes: When the refrigerator enters the refrigeration mode, connect the second interface of the two-way three-way solenoid valve to the third interface and close the second interface.

10. The defrosting control method of the refrigerator according to claim 9, characterized in that, The refrigerator further includes: A temperature sensor for detecting the current temperature of the first evaporator; The method further includes: After power-on, start the refrigerator in the refrigeration mode and detect the current temperature of the first evaporator; When the detected current temperature is not higher than a preset defrosting temperature threshold, control the refrigerator to enter the defrosting mode, calculate the operation duration of the defrosting mode and continue to detect the current temperature; When the operation duration is not less than a preset duration threshold and the currently detected current temperature is higher than the defrosting temperature threshold, control the refrigerator to enter the refrigeration mode.

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